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Select CONFIG_MICROCODE_LATE_LOADING #4

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pmenzel opened this issue Sep 11, 2023 · 3 comments
Closed

Select CONFIG_MICROCODE_LATE_LOADING #4

pmenzel opened this issue Sep 11, 2023 · 3 comments

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@pmenzel
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pmenzel commented Sep 11, 2023

$ grep LATE_LOADI /boot/config-*
/boot/config-5.15.112.mx64.449:# CONFIG_MICROCODE_LATE_LOADING is not set
/boot/config-6.1.39.mx64.450:# CONFIG_MICROCODE_LATE_LOADING is not set
/boot/config-6.5.2.mx64.452:# CONFIG_MICROCODE_LATE_LOADING is not set
config MICROCODE_LATE_LOADING
        bool "Late microcode loading (DANGEROUS)"
        default n
        depends on MICROCODE
        help                                             
          Loading microcode late, when the system is up and executing instructions
          is a tricky business and should be avoided if possible. Just the sequence
          of synchronizing all cores and SMT threads is one fragile dance which does
          not guarantee that cores might not softlock after the loading. Therefore,
          use this at your own risk. Late loading taints the kernel too.
@pmenzel
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pmenzel commented Sep 11, 2023

Allows to run:

# echo 1 > /sys/devices/system/cpu/microcode/reload

@pmenzel
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pmenzel commented Sep 11, 2023

Commit a77a94f862 (x86/microcode: Default-disable late loading) introduced the Kconfig option, defaulting to no, so it was disabled in our systems as it was backported to Linux v5.15.99 (commit 6d2b3a319144f3f5148d8a2b19549ea3bb118c2e).

@donald
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donald commented Sep 11, 2023

donald pushed a commit that referenced this issue Sep 14, 2023
[ Upstream commit 3136a0f ]

For normal GPU devfreq, we need to acquire the GMU lock while already
holding devfreq locks.  But in the teardown path, we were calling
dev_pm_domain_detach() while already holding the GMU lock, resulting in
this lockdep splat:

   ======================================================
   WARNING: possible circular locking dependency detected
   6.4.3-debug+ #3 Not tainted
   ------------------------------------------------------
   ring0/391 is trying to acquire lock:
   ffffff80a025c078 (&devfreq->lock){+.+.}-{3:3}, at: qos_notifier_call+0x30/0x74

   but task is already holding lock:
   ffffff809b8c1ce8 (&(c->notifiers)->rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x34/0x78

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #4 (&(c->notifiers)->rwsem){++++}-{3:3}:
          down_write+0x58/0x74
          __blocking_notifier_chain_register+0x64/0x84
          blocking_notifier_chain_register+0x1c/0x28
          freq_qos_add_notifier+0x5c/0x7c
          dev_pm_qos_add_notifier+0xd4/0xf0
          devfreq_add_device+0x42c/0x560
          devm_devfreq_add_device+0x6c/0xb8
          msm_devfreq_init+0xa8/0x16c [msm]
          msm_gpu_init+0x368/0x54c [msm]
          adreno_gpu_init+0x248/0x2b0 [msm]
          a6xx_gpu_init+0x2d0/0x384 [msm]
          adreno_bind+0x264/0x2bc [msm]
          component_bind_all+0x124/0x1f4
          msm_drm_bind+0x2d0/0x5f4 [msm]
          try_to_bring_up_aggregate_device+0x88/0x1a4
          __component_add+0xd4/0x128
          component_add+0x1c/0x28
          dp_display_probe+0x37c/0x3c0 [msm]
          platform_probe+0x70/0xc0
          really_probe+0x148/0x280
          __driver_probe_device+0xfc/0x114
          driver_probe_device+0x44/0x100
          __device_attach_driver+0x64/0xdc
          bus_for_each_drv+0xb0/0xd8
          __device_attach+0xe4/0x140
          device_initial_probe+0x1c/0x28
          bus_probe_device+0x44/0xb0
          deferred_probe_work_func+0xb0/0xc8
          process_one_work+0x288/0x3d8
          worker_thread+0x1f0/0x260
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   -> #3 (dev_pm_qos_mtx){+.+.}-{3:3}:
          __mutex_lock+0xc8/0x388
          mutex_lock_nested+0x2c/0x38
          dev_pm_qos_remove_notifier+0x3c/0xc8
          genpd_remove_device+0x40/0x11c
          genpd_dev_pm_detach+0x88/0x130
          dev_pm_domain_detach+0x2c/0x3c
          a6xx_gmu_remove+0x44/0xdc [msm]
          a6xx_destroy+0x7c/0xa4 [msm]
          adreno_unbind+0x50/0x64 [msm]
          component_unbind+0x44/0x64
          component_unbind_all+0xb4/0xbc
          msm_drm_uninit.isra.0+0x124/0x17c [msm]
          msm_drm_bind+0x340/0x5f4 [msm]
          try_to_bring_up_aggregate_device+0x88/0x1a4
          __component_add+0xd4/0x128
          component_add+0x1c/0x28
          dp_display_probe+0x37c/0x3c0 [msm]
          platform_probe+0x70/0xc0
          really_probe+0x148/0x280
          __driver_probe_device+0xfc/0x114
          driver_probe_device+0x44/0x100
          __device_attach_driver+0x64/0xdc
          bus_for_each_drv+0xb0/0xd8
          __device_attach+0xe4/0x140
          device_initial_probe+0x1c/0x28
          bus_probe_device+0x44/0xb0
          deferred_probe_work_func+0xb0/0xc8
          process_one_work+0x288/0x3d8
          worker_thread+0x1f0/0x260
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   -> #2 (&a6xx_gpu->gmu.lock){+.+.}-{3:3}:
          __mutex_lock+0xc8/0x388
          mutex_lock_nested+0x2c/0x38
          a6xx_gpu_set_freq+0x38/0x64 [msm]
          msm_devfreq_target+0x170/0x18c [msm]
          devfreq_set_target+0x90/0x1e4
          devfreq_update_target+0xb4/0xf0
          update_devfreq+0x1c/0x28
          devfreq_monitor+0x3c/0x10c
          process_one_work+0x288/0x3d8
          worker_thread+0x1f0/0x260
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   -> #1 (&df->lock){+.+.}-{3:3}:
          __mutex_lock+0xc8/0x388
          mutex_lock_nested+0x2c/0x38
          msm_devfreq_get_dev_status+0x4c/0x104 [msm]
          devfreq_simple_ondemand_func+0x5c/0x128
          devfreq_update_target+0x68/0xf0
          update_devfreq+0x1c/0x28
          devfreq_monitor+0x3c/0x10c
          process_one_work+0x288/0x3d8
          worker_thread+0x1f0/0x260
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   -> #0 (&devfreq->lock){+.+.}-{3:3}:
          __lock_acquire+0xdf8/0x109c
          lock_acquire+0x234/0x284
          __mutex_lock+0xc8/0x388
          mutex_lock_nested+0x2c/0x38
          qos_notifier_call+0x30/0x74
          qos_min_notifier_call+0x1c/0x28
          notifier_call_chain+0xf4/0x114
          blocking_notifier_call_chain+0x4c/0x78
          pm_qos_update_target+0x184/0x190
          freq_qos_apply+0x4c/0x64
          apply_constraint+0xf8/0xfc
          __dev_pm_qos_update_request+0x138/0x164
          dev_pm_qos_update_request+0x44/0x68
          msm_devfreq_boost+0x40/0x70 [msm]
          msm_devfreq_active+0xc0/0xf0 [msm]
          msm_gpu_submit+0xc8/0x12c [msm]
          msm_job_run+0x88/0x128 [msm]
          drm_sched_main+0x240/0x324 [gpu_sched]
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   other info that might help us debug this:
   Chain exists of:
     &devfreq->lock --> dev_pm_qos_mtx --> &(c->notifiers)->rwsem
    Possible unsafe locking scenario:
          CPU0                    CPU1
          ----                    ----
     rlock(&(c->notifiers)->rwsem);
                                  lock(dev_pm_qos_mtx);
                                  lock(&(c->notifiers)->rwsem);
     lock(&devfreq->lock);

    *** DEADLOCK ***
   4 locks held by ring0/391:
    #0: ffffff809c811170 (&gpu->lock){+.+.}-{3:3}, at: msm_job_run+0x7c/0x128 [msm]
    #1: ffffff809c811208 (&gpu->active_lock){+.+.}-{3:3}, at: msm_gpu_submit+0xa8/0x12c [msm]
    #2: ffffffecbbb46600 (dev_pm_qos_mtx){+.+.}-{3:3}, at: dev_pm_qos_update_request+0x38/0x68
    #3: ffffff809b8c1ce8 (&(c->notifiers)->rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x34/0x78

   stack backtrace:
   CPU: 6 PID: 391 Comm: ring0 Not tainted 6.4.3debug+ #3
   Hardware name: Google Villager (rev1+) with LTE (DT)
   Call trace:
    dump_backtrace+0xb4/0xf0
    show_stack+0x20/0x30
    dump_stack_lvl+0x60/0x84
    dump_stack+0x18/0x24
    print_circular_bug+0x1cc/0x234
    check_noncircular+0x78/0xac
    __lock_acquire+0xdf8/0x109c
    lock_acquire+0x234/0x284
    __mutex_lock+0xc8/0x388
    mutex_lock_nested+0x2c/0x38
    qos_notifier_call+0x30/0x74
    qos_min_notifier_call+0x1c/0x28
    notifier_call_chain+0xf4/0x114
    blocking_notifier_call_chain+0x4c/0x78
    pm_qos_update_target+0x184/0x190
    freq_qos_apply+0x4c/0x64
    apply_constraint+0xf8/0xfc
    __dev_pm_qos_update_request+0x138/0x164
    dev_pm_qos_update_request+0x44/0x68
    msm_devfreq_boost+0x40/0x70 [msm]
    msm_devfreq_active+0xc0/0xf0 [msm]
    msm_gpu_submit+0xc8/0x12c [msm]
    msm_job_run+0x88/0x128 [msm]
    drm_sched_main+0x240/0x324 [gpu_sched]
    kthread+0xf0/0x100
    ret_from_fork+0x10/0x20

Fix this by only synchronizing access to gmu->initialized.

Fixes: 4cd15a3 ("drm/msm/a6xx: Make GPU destroy a bit safer")
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/551171/
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 14, 2023
[ Upstream commit 3136a0f ]

For normal GPU devfreq, we need to acquire the GMU lock while already
holding devfreq locks.  But in the teardown path, we were calling
dev_pm_domain_detach() while already holding the GMU lock, resulting in
this lockdep splat:

   ======================================================
   WARNING: possible circular locking dependency detected
   6.4.3-debug+ #3 Not tainted
   ------------------------------------------------------
   ring0/391 is trying to acquire lock:
   ffffff80a025c078 (&devfreq->lock){+.+.}-{3:3}, at: qos_notifier_call+0x30/0x74

   but task is already holding lock:
   ffffff809b8c1ce8 (&(c->notifiers)->rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x34/0x78

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #4 (&(c->notifiers)->rwsem){++++}-{3:3}:
          down_write+0x58/0x74
          __blocking_notifier_chain_register+0x64/0x84
          blocking_notifier_chain_register+0x1c/0x28
          freq_qos_add_notifier+0x5c/0x7c
          dev_pm_qos_add_notifier+0xd4/0xf0
          devfreq_add_device+0x42c/0x560
          devm_devfreq_add_device+0x6c/0xb8
          msm_devfreq_init+0xa8/0x16c [msm]
          msm_gpu_init+0x368/0x54c [msm]
          adreno_gpu_init+0x248/0x2b0 [msm]
          a6xx_gpu_init+0x2d0/0x384 [msm]
          adreno_bind+0x264/0x2bc [msm]
          component_bind_all+0x124/0x1f4
          msm_drm_bind+0x2d0/0x5f4 [msm]
          try_to_bring_up_aggregate_device+0x88/0x1a4
          __component_add+0xd4/0x128
          component_add+0x1c/0x28
          dp_display_probe+0x37c/0x3c0 [msm]
          platform_probe+0x70/0xc0
          really_probe+0x148/0x280
          __driver_probe_device+0xfc/0x114
          driver_probe_device+0x44/0x100
          __device_attach_driver+0x64/0xdc
          bus_for_each_drv+0xb0/0xd8
          __device_attach+0xe4/0x140
          device_initial_probe+0x1c/0x28
          bus_probe_device+0x44/0xb0
          deferred_probe_work_func+0xb0/0xc8
          process_one_work+0x288/0x3d8
          worker_thread+0x1f0/0x260
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   -> #3 (dev_pm_qos_mtx){+.+.}-{3:3}:
          __mutex_lock+0xc8/0x388
          mutex_lock_nested+0x2c/0x38
          dev_pm_qos_remove_notifier+0x3c/0xc8
          genpd_remove_device+0x40/0x11c
          genpd_dev_pm_detach+0x88/0x130
          dev_pm_domain_detach+0x2c/0x3c
          a6xx_gmu_remove+0x44/0xdc [msm]
          a6xx_destroy+0x7c/0xa4 [msm]
          adreno_unbind+0x50/0x64 [msm]
          component_unbind+0x44/0x64
          component_unbind_all+0xb4/0xbc
          msm_drm_uninit.isra.0+0x124/0x17c [msm]
          msm_drm_bind+0x340/0x5f4 [msm]
          try_to_bring_up_aggregate_device+0x88/0x1a4
          __component_add+0xd4/0x128
          component_add+0x1c/0x28
          dp_display_probe+0x37c/0x3c0 [msm]
          platform_probe+0x70/0xc0
          really_probe+0x148/0x280
          __driver_probe_device+0xfc/0x114
          driver_probe_device+0x44/0x100
          __device_attach_driver+0x64/0xdc
          bus_for_each_drv+0xb0/0xd8
          __device_attach+0xe4/0x140
          device_initial_probe+0x1c/0x28
          bus_probe_device+0x44/0xb0
          deferred_probe_work_func+0xb0/0xc8
          process_one_work+0x288/0x3d8
          worker_thread+0x1f0/0x260
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   -> #2 (&a6xx_gpu->gmu.lock){+.+.}-{3:3}:
          __mutex_lock+0xc8/0x388
          mutex_lock_nested+0x2c/0x38
          a6xx_gpu_set_freq+0x38/0x64 [msm]
          msm_devfreq_target+0x170/0x18c [msm]
          devfreq_set_target+0x90/0x1e4
          devfreq_update_target+0xb4/0xf0
          update_devfreq+0x1c/0x28
          devfreq_monitor+0x3c/0x10c
          process_one_work+0x288/0x3d8
          worker_thread+0x1f0/0x260
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   -> #1 (&df->lock){+.+.}-{3:3}:
          __mutex_lock+0xc8/0x388
          mutex_lock_nested+0x2c/0x38
          msm_devfreq_get_dev_status+0x4c/0x104 [msm]
          devfreq_simple_ondemand_func+0x5c/0x128
          devfreq_update_target+0x68/0xf0
          update_devfreq+0x1c/0x28
          devfreq_monitor+0x3c/0x10c
          process_one_work+0x288/0x3d8
          worker_thread+0x1f0/0x260
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   -> #0 (&devfreq->lock){+.+.}-{3:3}:
          __lock_acquire+0xdf8/0x109c
          lock_acquire+0x234/0x284
          __mutex_lock+0xc8/0x388
          mutex_lock_nested+0x2c/0x38
          qos_notifier_call+0x30/0x74
          qos_min_notifier_call+0x1c/0x28
          notifier_call_chain+0xf4/0x114
          blocking_notifier_call_chain+0x4c/0x78
          pm_qos_update_target+0x184/0x190
          freq_qos_apply+0x4c/0x64
          apply_constraint+0xf8/0xfc
          __dev_pm_qos_update_request+0x138/0x164
          dev_pm_qos_update_request+0x44/0x68
          msm_devfreq_boost+0x40/0x70 [msm]
          msm_devfreq_active+0xc0/0xf0 [msm]
          msm_gpu_submit+0xc8/0x12c [msm]
          msm_job_run+0x88/0x128 [msm]
          drm_sched_main+0x240/0x324 [gpu_sched]
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   other info that might help us debug this:
   Chain exists of:
     &devfreq->lock --> dev_pm_qos_mtx --> &(c->notifiers)->rwsem
    Possible unsafe locking scenario:
          CPU0                    CPU1
          ----                    ----
     rlock(&(c->notifiers)->rwsem);
                                  lock(dev_pm_qos_mtx);
                                  lock(&(c->notifiers)->rwsem);
     lock(&devfreq->lock);

    *** DEADLOCK ***
   4 locks held by ring0/391:
    #0: ffffff809c811170 (&gpu->lock){+.+.}-{3:3}, at: msm_job_run+0x7c/0x128 [msm]
    #1: ffffff809c811208 (&gpu->active_lock){+.+.}-{3:3}, at: msm_gpu_submit+0xa8/0x12c [msm]
    #2: ffffffecbbb46600 (dev_pm_qos_mtx){+.+.}-{3:3}, at: dev_pm_qos_update_request+0x38/0x68
    #3: ffffff809b8c1ce8 (&(c->notifiers)->rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x34/0x78

   stack backtrace:
   CPU: 6 PID: 391 Comm: ring0 Not tainted 6.4.3debug+ #3
   Hardware name: Google Villager (rev1+) with LTE (DT)
   Call trace:
    dump_backtrace+0xb4/0xf0
    show_stack+0x20/0x30
    dump_stack_lvl+0x60/0x84
    dump_stack+0x18/0x24
    print_circular_bug+0x1cc/0x234
    check_noncircular+0x78/0xac
    __lock_acquire+0xdf8/0x109c
    lock_acquire+0x234/0x284
    __mutex_lock+0xc8/0x388
    mutex_lock_nested+0x2c/0x38
    qos_notifier_call+0x30/0x74
    qos_min_notifier_call+0x1c/0x28
    notifier_call_chain+0xf4/0x114
    blocking_notifier_call_chain+0x4c/0x78
    pm_qos_update_target+0x184/0x190
    freq_qos_apply+0x4c/0x64
    apply_constraint+0xf8/0xfc
    __dev_pm_qos_update_request+0x138/0x164
    dev_pm_qos_update_request+0x44/0x68
    msm_devfreq_boost+0x40/0x70 [msm]
    msm_devfreq_active+0xc0/0xf0 [msm]
    msm_gpu_submit+0xc8/0x12c [msm]
    msm_job_run+0x88/0x128 [msm]
    drm_sched_main+0x240/0x324 [gpu_sched]
    kthread+0xf0/0x100
    ret_from_fork+0x10/0x20

Fix this by only synchronizing access to gmu->initialized.

Fixes: 4cd15a3 ("drm/msm/a6xx: Make GPU destroy a bit safer")
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/551171/
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 14, 2023
[ Upstream commit fe48ba7 ]

KCSAN has discovered a data race in kernel/workqueue.c:2598:

[ 1863.554079] ==================================================================
[ 1863.554118] BUG: KCSAN: data-race in process_one_work / process_one_work

[ 1863.554142] write to 0xffff963d99d79998 of 8 bytes by task 5394 on cpu 27:
[ 1863.554154] process_one_work (kernel/workqueue.c:2598)
[ 1863.554166] worker_thread (./include/linux/list.h:292 kernel/workqueue.c:2752)
[ 1863.554177] kthread (kernel/kthread.c:389)
[ 1863.554186] ret_from_fork (arch/x86/kernel/process.c:145)
[ 1863.554197] ret_from_fork_asm (arch/x86/entry/entry_64.S:312)

[ 1863.554213] read to 0xffff963d99d79998 of 8 bytes by task 5450 on cpu 12:
[ 1863.554224] process_one_work (kernel/workqueue.c:2598)
[ 1863.554235] worker_thread (./include/linux/list.h:292 kernel/workqueue.c:2752)
[ 1863.554247] kthread (kernel/kthread.c:389)
[ 1863.554255] ret_from_fork (arch/x86/kernel/process.c:145)
[ 1863.554266] ret_from_fork_asm (arch/x86/entry/entry_64.S:312)

[ 1863.554280] value changed: 0x0000000000001766 -> 0x000000000000176a

[ 1863.554295] Reported by Kernel Concurrency Sanitizer on:
[ 1863.554303] CPU: 12 PID: 5450 Comm: kworker/u64:1 Tainted: G             L     6.5.0-rc6+ #44
[ 1863.554314] Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023
[ 1863.554322] Workqueue: btrfs-endio btrfs_end_bio_work [btrfs]
[ 1863.554941] ==================================================================

    lockdep_invariant_state(true);
→   pwq->stats[PWQ_STAT_STARTED]++;
    trace_workqueue_execute_start(work);
    worker->current_func(work);

Moving pwq->stats[PWQ_STAT_STARTED]++; before the line

    raw_spin_unlock_irq(&pool->lock);

resolves the data race without performance penalty.

KCSAN detected at least one additional data race:

[  157.834751] ==================================================================
[  157.834770] BUG: KCSAN: data-race in process_one_work / process_one_work

[  157.834793] write to 0xffff9934453f77a0 of 8 bytes by task 468 on cpu 29:
[  157.834804] process_one_work (/home/marvin/linux/kernel/linux_torvalds/kernel/workqueue.c:2606)
[  157.834815] worker_thread (/home/marvin/linux/kernel/linux_torvalds/./include/linux/list.h:292 /home/marvin/linux/kernel/linux_torvalds/kernel/workqueue.c:2752)
[  157.834826] kthread (/home/marvin/linux/kernel/linux_torvalds/kernel/kthread.c:389)
[  157.834834] ret_from_fork (/home/marvin/linux/kernel/linux_torvalds/arch/x86/kernel/process.c:145)
[  157.834845] ret_from_fork_asm (/home/marvin/linux/kernel/linux_torvalds/arch/x86/entry/entry_64.S:312)

[  157.834859] read to 0xffff9934453f77a0 of 8 bytes by task 214 on cpu 7:
[  157.834868] process_one_work (/home/marvin/linux/kernel/linux_torvalds/kernel/workqueue.c:2606)
[  157.834879] worker_thread (/home/marvin/linux/kernel/linux_torvalds/./include/linux/list.h:292 /home/marvin/linux/kernel/linux_torvalds/kernel/workqueue.c:2752)
[  157.834890] kthread (/home/marvin/linux/kernel/linux_torvalds/kernel/kthread.c:389)
[  157.834897] ret_from_fork (/home/marvin/linux/kernel/linux_torvalds/arch/x86/kernel/process.c:145)
[  157.834907] ret_from_fork_asm (/home/marvin/linux/kernel/linux_torvalds/arch/x86/entry/entry_64.S:312)

[  157.834920] value changed: 0x000000000000052a -> 0x0000000000000532

[  157.834933] Reported by Kernel Concurrency Sanitizer on:
[  157.834941] CPU: 7 PID: 214 Comm: kworker/u64:2 Tainted: G             L     6.5.0-rc7-kcsan-00169-g81eaf55a60fc #4
[  157.834951] Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023
[  157.834958] Workqueue: btrfs-endio btrfs_end_bio_work [btrfs]
[  157.835567] ==================================================================

in code:

        trace_workqueue_execute_end(work, worker->current_func);
→       pwq->stats[PWQ_STAT_COMPLETED]++;
        lock_map_release(&lockdep_map);
        lock_map_release(&pwq->wq->lockdep_map);

which needs to be resolved separately.

Fixes: 725e8ec ("workqueue: Add pwq->stats[] and a monitoring script")
Cc: Tejun Heo <tj@kernel.org>
Suggested-by: Lai Jiangshan <jiangshanlai@gmail.com>
Link: https://lore.kernel.org/lkml/20230818194448.29672-1-mirsad.todorovac@alu.unizg.hr/
Signed-off-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 16, 2023
Except for initial reference, mddev->kobject is referenced by
rdev->kobject, and if the last rdev is freed, there is no guarantee that
mddev is still valid. Hence mddev should not be used anymore after
export_rdev().

This problem can be triggered by following test for mdadm at very
low rate:

New file: mdadm/tests/23rdev-lifetime

devname=${dev0##*/}
devt=`cat /sys/block/$devname/dev`
pid=""
runtime=2

clean_up_test() {
        pill -9 $pid
        echo clear > /sys/block/md0/md/array_state
}

trap 'clean_up_test' EXIT

add_by_sysfs() {
        while true; do
                echo $devt > /sys/block/md0/md/new_dev
        done
}

remove_by_sysfs(){
        while true; do
                echo remove > /sys/block/md0/md/dev-${devname}/state
        done
}

echo md0 > /sys/module/md_mod/parameters/new_array || die "create md0 failed"

add_by_sysfs &
pid="$pid $!"

remove_by_sysfs &
pid="$pid $!"

sleep $runtime
exit 0

Test cmd:

./test --save-logs --logdir=/tmp/ --keep-going --dev=loop --tests=23rdev-lifetime

Test result:

general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bcb: 0000 [#4] PREEMPT SMP
CPU: 0 PID: 1292 Comm: test Tainted: G      D W          6.5.0-rc2-00121-g01e55c376936 #562
RIP: 0010:md_wakeup_thread+0x9e/0x320 [md_mod]
Call Trace:
 <TASK>
 mddev_unlock+0x1b6/0x310 [md_mod]
 rdev_attr_store+0xec/0x190 [md_mod]
 sysfs_kf_write+0x52/0x70
 kernfs_fop_write_iter+0x19a/0x2a0
 vfs_write+0x3b5/0x770
 ksys_write+0x74/0x150
 __x64_sys_write+0x22/0x30
 do_syscall_64+0x40/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fix this problem by don't dereference mddev after export_rdev().

Fixes: 3ce94ce ("md: fix duplicate filename for rdev")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825025532.1523008-2-yukuai1@huaweicloud.com
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit ef23cb5 ]

While debugging a segfault on 'perf lock contention' without an
available perf.data file I noticed that it was basically calling:

	perf_session__delete(ERR_PTR(-1))

Resulting in:

  (gdb) run lock contention
  Starting program: /root/bin/perf lock contention
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  Initializing perf session failed

  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  2858		if (!session->auxtrace)
  (gdb) p session
  $1 = (struct perf_session *) 0xffffffffffffffff
  (gdb) bt
  #0  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  #1  0x000000000057bb4d in perf_session__delete (session=0xffffffffffffffff) at util/session.c:300
  #2  0x000000000047c421 in __cmd_contention (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2161
  #3  0x000000000047dc95 in cmd_lock (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2604
  #4  0x0000000000501466 in run_builtin (p=0xe597a8 <commands+552>, argc=2, argv=0x7fffffffe200) at perf.c:322
  #5  0x00000000005016d5 in handle_internal_command (argc=2, argv=0x7fffffffe200) at perf.c:375
  #6  0x0000000000501824 in run_argv (argcp=0x7fffffffe02c, argv=0x7fffffffe020) at perf.c:419
  #7  0x0000000000501b11 in main (argc=2, argv=0x7fffffffe200) at perf.c:535
  (gdb)

So just set it to NULL after using PTR_ERR(session) to decode the error
as perf_session__delete(NULL) is supported.

The same problem was found in 'perf top' after an audit of all
perf_session__new() failure handling.

Fixes: 6ef81c5 ("perf session: Return error code for perf_session__new() function on failure")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeremie Galarneau <jeremie.galarneau@efficios.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mukesh Ojha <mojha@codeaurora.org>
Cc: Nageswara R Sastry <rnsastry@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Shawn Landden <shawn@git.icu>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Link: https://lore.kernel.org/lkml/ZN4Q2rxxsL08A8rd@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit 8fc134f ]

When the plug qdisc is used as a class of the qfq qdisc it could trigger a
UAF. This issue can be reproduced with following commands:

  tc qdisc add dev lo root handle 1: qfq
  tc class add dev lo parent 1: classid 1:1 qfq weight 1 maxpkt 512
  tc qdisc add dev lo parent 1:1 handle 2: plug
  tc filter add dev lo parent 1: basic classid 1:1
  ping -c1 127.0.0.1

and boom:

[  285.353793] BUG: KASAN: slab-use-after-free in qfq_dequeue+0xa7/0x7f0
[  285.354910] Read of size 4 at addr ffff8880bad312a8 by task ping/144
[  285.355903]
[  285.356165] CPU: 1 PID: 144 Comm: ping Not tainted 6.5.0-rc3+ #4
[  285.357112] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
[  285.358376] Call Trace:
[  285.358773]  <IRQ>
[  285.359109]  dump_stack_lvl+0x44/0x60
[  285.359708]  print_address_description.constprop.0+0x2c/0x3c0
[  285.360611]  kasan_report+0x10c/0x120
[  285.361195]  ? qfq_dequeue+0xa7/0x7f0
[  285.361780]  qfq_dequeue+0xa7/0x7f0
[  285.362342]  __qdisc_run+0xf1/0x970
[  285.362903]  net_tx_action+0x28e/0x460
[  285.363502]  __do_softirq+0x11b/0x3de
[  285.364097]  do_softirq.part.0+0x72/0x90
[  285.364721]  </IRQ>
[  285.365072]  <TASK>
[  285.365422]  __local_bh_enable_ip+0x77/0x90
[  285.366079]  __dev_queue_xmit+0x95f/0x1550
[  285.366732]  ? __pfx_csum_and_copy_from_iter+0x10/0x10
[  285.367526]  ? __pfx___dev_queue_xmit+0x10/0x10
[  285.368259]  ? __build_skb_around+0x129/0x190
[  285.368960]  ? ip_generic_getfrag+0x12c/0x170
[  285.369653]  ? __pfx_ip_generic_getfrag+0x10/0x10
[  285.370390]  ? csum_partial+0x8/0x20
[  285.370961]  ? raw_getfrag+0xe5/0x140
[  285.371559]  ip_finish_output2+0x539/0xa40
[  285.372222]  ? __pfx_ip_finish_output2+0x10/0x10
[  285.372954]  ip_output+0x113/0x1e0
[  285.373512]  ? __pfx_ip_output+0x10/0x10
[  285.374130]  ? icmp_out_count+0x49/0x60
[  285.374739]  ? __pfx_ip_finish_output+0x10/0x10
[  285.375457]  ip_push_pending_frames+0xf3/0x100
[  285.376173]  raw_sendmsg+0xef5/0x12d0
[  285.376760]  ? do_syscall_64+0x40/0x90
[  285.377359]  ? __static_call_text_end+0x136578/0x136578
[  285.378173]  ? do_syscall_64+0x40/0x90
[  285.378772]  ? kasan_enable_current+0x11/0x20
[  285.379469]  ? __pfx_raw_sendmsg+0x10/0x10
[  285.380137]  ? __sock_create+0x13e/0x270
[  285.380673]  ? __sys_socket+0xf3/0x180
[  285.381174]  ? __x64_sys_socket+0x3d/0x50
[  285.381725]  ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.382425]  ? __rcu_read_unlock+0x48/0x70
[  285.382975]  ? ip4_datagram_release_cb+0xd8/0x380
[  285.383608]  ? __pfx_ip4_datagram_release_cb+0x10/0x10
[  285.384295]  ? preempt_count_sub+0x14/0xc0
[  285.384844]  ? __list_del_entry_valid+0x76/0x140
[  285.385467]  ? _raw_spin_lock_bh+0x87/0xe0
[  285.386014]  ? __pfx__raw_spin_lock_bh+0x10/0x10
[  285.386645]  ? release_sock+0xa0/0xd0
[  285.387148]  ? preempt_count_sub+0x14/0xc0
[  285.387712]  ? freeze_secondary_cpus+0x348/0x3c0
[  285.388341]  ? aa_sk_perm+0x177/0x390
[  285.388856]  ? __pfx_aa_sk_perm+0x10/0x10
[  285.389441]  ? check_stack_object+0x22/0x70
[  285.390032]  ? inet_send_prepare+0x2f/0x120
[  285.390603]  ? __pfx_inet_sendmsg+0x10/0x10
[  285.391172]  sock_sendmsg+0xcc/0xe0
[  285.391667]  __sys_sendto+0x190/0x230
[  285.392168]  ? __pfx___sys_sendto+0x10/0x10
[  285.392727]  ? kvm_clock_get_cycles+0x14/0x30
[  285.393328]  ? set_normalized_timespec64+0x57/0x70
[  285.393980]  ? _raw_spin_unlock_irq+0x1b/0x40
[  285.394578]  ? __x64_sys_clock_gettime+0x11c/0x160
[  285.395225]  ? __pfx___x64_sys_clock_gettime+0x10/0x10
[  285.395908]  ? _copy_to_user+0x3e/0x60
[  285.396432]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.397086]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.397734]  ? do_syscall_64+0x71/0x90
[  285.398258]  __x64_sys_sendto+0x74/0x90
[  285.398786]  do_syscall_64+0x64/0x90
[  285.399273]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.399949]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.400605]  ? do_syscall_64+0x71/0x90
[  285.401124]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.401807] RIP: 0033:0x495726
[  285.402233] Code: ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 09
[  285.404683] RSP: 002b:00007ffcc25fb618 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[  285.405677] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 0000000000495726
[  285.406628] RDX: 0000000000000040 RSI: 0000000002518750 RDI: 0000000000000000
[  285.407565] RBP: 00000000005205ef R08: 00000000005f8838 R09: 000000000000001c
[  285.408523] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002517634
[  285.409460] R13: 00007ffcc25fb6f0 R14: 0000000000000003 R15: 0000000000000000
[  285.410403]  </TASK>
[  285.410704]
[  285.410929] Allocated by task 144:
[  285.411402]  kasan_save_stack+0x1e/0x40
[  285.411926]  kasan_set_track+0x21/0x30
[  285.412442]  __kasan_slab_alloc+0x55/0x70
[  285.412973]  kmem_cache_alloc_node+0x187/0x3d0
[  285.413567]  __alloc_skb+0x1b4/0x230
[  285.414060]  __ip_append_data+0x17f7/0x1b60
[  285.414633]  ip_append_data+0x97/0xf0
[  285.415144]  raw_sendmsg+0x5a8/0x12d0
[  285.415640]  sock_sendmsg+0xcc/0xe0
[  285.416117]  __sys_sendto+0x190/0x230
[  285.416626]  __x64_sys_sendto+0x74/0x90
[  285.417145]  do_syscall_64+0x64/0x90
[  285.417624]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.418306]
[  285.418531] Freed by task 144:
[  285.418960]  kasan_save_stack+0x1e/0x40
[  285.419469]  kasan_set_track+0x21/0x30
[  285.419988]  kasan_save_free_info+0x27/0x40
[  285.420556]  ____kasan_slab_free+0x109/0x1a0
[  285.421146]  kmem_cache_free+0x1c2/0x450
[  285.421680]  __netif_receive_skb_core+0x2ce/0x1870
[  285.422333]  __netif_receive_skb_one_core+0x97/0x140
[  285.423003]  process_backlog+0x100/0x2f0
[  285.423537]  __napi_poll+0x5c/0x2d0
[  285.424023]  net_rx_action+0x2be/0x560
[  285.424510]  __do_softirq+0x11b/0x3de
[  285.425034]
[  285.425254] The buggy address belongs to the object at ffff8880bad31280
[  285.425254]  which belongs to the cache skbuff_head_cache of size 224
[  285.426993] The buggy address is located 40 bytes inside of
[  285.426993]  freed 224-byte region [ffff8880bad31280, ffff8880bad31360)
[  285.428572]
[  285.428798] The buggy address belongs to the physical page:
[  285.429540] page:00000000f4b77674 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xbad31
[  285.430758] flags: 0x100000000000200(slab|node=0|zone=1)
[  285.431447] page_type: 0xffffffff()
[  285.431934] raw: 0100000000000200 ffff88810094a8c0 dead000000000122 0000000000000000
[  285.432757] raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
[  285.433562] page dumped because: kasan: bad access detected
[  285.434144]
[  285.434320] Memory state around the buggy address:
[  285.434828]  ffff8880bad31180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.435580]  ffff8880bad31200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.436264] >ffff8880bad31280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  285.436777]                                   ^
[  285.437106]  ffff8880bad31300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
[  285.437616]  ffff8880bad31380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.438126] ==================================================================
[  285.438662] Disabling lock debugging due to kernel taint

Fix this by:
1. Changing sch_plug's .peek handler to qdisc_peek_dequeued(), a
function compatible with non-work-conserving qdiscs
2. Checking the return value of qdisc_dequeue_peeked() in sch_qfq.

Fixes: 462dbc9 ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Reported-by: valis <sec@valis.email>
Signed-off-by: valis <sec@valis.email>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20230901162237.11525-1-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit 7962ef1 ]

In 3cb4d5e ("perf trace: Free syscall tp fields in
evsel->priv") it only was freeing if strcmp(evsel->tp_format->system,
"syscalls") returned zero, while the corresponding initialization of
evsel->priv was being performed if it was _not_ zero, i.e. if the tp
system wasn't 'syscalls'.

Just stop looking for that and free it if evsel->priv was set, which
should be equivalent.

Also use the pre-existing evsel_trace__delete() function.

This resolves these leaks, detected with:

  $ make EXTRA_CFLAGS="-fsanitize=address" BUILD_BPF_SKEL=1 CORESIGHT=1 O=/tmp/build/perf-tools-next -C tools/perf install-bin

  =================================================================
  ==481565==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f7343cba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x987966 in zalloc (/home/acme/bin/perf+0x987966)
      #2 0x52f9b9 in evsel_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:307
      #3 0x52f9b9 in evsel__syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:333
      #4 0x52f9b9 in evsel__init_raw_syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:458
      #5 0x52f9b9 in perf_evsel__raw_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:480
      #6 0x540e8b in trace__add_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3212
      #7 0x540e8b in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3891
      #8 0x540e8b in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5156
      #9 0x5ef262 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #10 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #11 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #12 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
      #13 0x7f7342c4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f7343cba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x987966 in zalloc (/home/acme/bin/perf+0x987966)
      #2 0x52f9b9 in evsel_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:307
      #3 0x52f9b9 in evsel__syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:333
      #4 0x52f9b9 in evsel__init_raw_syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:458
      #5 0x52f9b9 in perf_evsel__raw_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:480
      #6 0x540dd1 in trace__add_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3205
      #7 0x540dd1 in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3891
      #8 0x540dd1 in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5156
      #9 0x5ef262 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #10 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #11 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #12 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
      #13 0x7f7342c4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  SUMMARY: AddressSanitizer: 80 byte(s) leaked in 2 allocation(s).
  [root@quaco ~]#

With this we plug all leaks with "perf trace sleep 1".

Fixes: 3cb4d5e ("perf trace: Free syscall tp fields in evsel->priv")
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Link: https://lore.kernel.org/lkml/20230719202951.534582-5-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit ef23cb5 ]

While debugging a segfault on 'perf lock contention' without an
available perf.data file I noticed that it was basically calling:

	perf_session__delete(ERR_PTR(-1))

Resulting in:

  (gdb) run lock contention
  Starting program: /root/bin/perf lock contention
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  Initializing perf session failed

  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  2858		if (!session->auxtrace)
  (gdb) p session
  $1 = (struct perf_session *) 0xffffffffffffffff
  (gdb) bt
  #0  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  #1  0x000000000057bb4d in perf_session__delete (session=0xffffffffffffffff) at util/session.c:300
  #2  0x000000000047c421 in __cmd_contention (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2161
  #3  0x000000000047dc95 in cmd_lock (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2604
  #4  0x0000000000501466 in run_builtin (p=0xe597a8 <commands+552>, argc=2, argv=0x7fffffffe200) at perf.c:322
  #5  0x00000000005016d5 in handle_internal_command (argc=2, argv=0x7fffffffe200) at perf.c:375
  #6  0x0000000000501824 in run_argv (argcp=0x7fffffffe02c, argv=0x7fffffffe020) at perf.c:419
  #7  0x0000000000501b11 in main (argc=2, argv=0x7fffffffe200) at perf.c:535
  (gdb)

So just set it to NULL after using PTR_ERR(session) to decode the error
as perf_session__delete(NULL) is supported.

The same problem was found in 'perf top' after an audit of all
perf_session__new() failure handling.

Fixes: 6ef81c5 ("perf session: Return error code for perf_session__new() function on failure")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeremie Galarneau <jeremie.galarneau@efficios.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mukesh Ojha <mojha@codeaurora.org>
Cc: Nageswara R Sastry <rnsastry@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Shawn Landden <shawn@git.icu>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Link: https://lore.kernel.org/lkml/ZN4Q2rxxsL08A8rd@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit 8fc134f ]

When the plug qdisc is used as a class of the qfq qdisc it could trigger a
UAF. This issue can be reproduced with following commands:

  tc qdisc add dev lo root handle 1: qfq
  tc class add dev lo parent 1: classid 1:1 qfq weight 1 maxpkt 512
  tc qdisc add dev lo parent 1:1 handle 2: plug
  tc filter add dev lo parent 1: basic classid 1:1
  ping -c1 127.0.0.1

and boom:

[  285.353793] BUG: KASAN: slab-use-after-free in qfq_dequeue+0xa7/0x7f0
[  285.354910] Read of size 4 at addr ffff8880bad312a8 by task ping/144
[  285.355903]
[  285.356165] CPU: 1 PID: 144 Comm: ping Not tainted 6.5.0-rc3+ #4
[  285.357112] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
[  285.358376] Call Trace:
[  285.358773]  <IRQ>
[  285.359109]  dump_stack_lvl+0x44/0x60
[  285.359708]  print_address_description.constprop.0+0x2c/0x3c0
[  285.360611]  kasan_report+0x10c/0x120
[  285.361195]  ? qfq_dequeue+0xa7/0x7f0
[  285.361780]  qfq_dequeue+0xa7/0x7f0
[  285.362342]  __qdisc_run+0xf1/0x970
[  285.362903]  net_tx_action+0x28e/0x460
[  285.363502]  __do_softirq+0x11b/0x3de
[  285.364097]  do_softirq.part.0+0x72/0x90
[  285.364721]  </IRQ>
[  285.365072]  <TASK>
[  285.365422]  __local_bh_enable_ip+0x77/0x90
[  285.366079]  __dev_queue_xmit+0x95f/0x1550
[  285.366732]  ? __pfx_csum_and_copy_from_iter+0x10/0x10
[  285.367526]  ? __pfx___dev_queue_xmit+0x10/0x10
[  285.368259]  ? __build_skb_around+0x129/0x190
[  285.368960]  ? ip_generic_getfrag+0x12c/0x170
[  285.369653]  ? __pfx_ip_generic_getfrag+0x10/0x10
[  285.370390]  ? csum_partial+0x8/0x20
[  285.370961]  ? raw_getfrag+0xe5/0x140
[  285.371559]  ip_finish_output2+0x539/0xa40
[  285.372222]  ? __pfx_ip_finish_output2+0x10/0x10
[  285.372954]  ip_output+0x113/0x1e0
[  285.373512]  ? __pfx_ip_output+0x10/0x10
[  285.374130]  ? icmp_out_count+0x49/0x60
[  285.374739]  ? __pfx_ip_finish_output+0x10/0x10
[  285.375457]  ip_push_pending_frames+0xf3/0x100
[  285.376173]  raw_sendmsg+0xef5/0x12d0
[  285.376760]  ? do_syscall_64+0x40/0x90
[  285.377359]  ? __static_call_text_end+0x136578/0x136578
[  285.378173]  ? do_syscall_64+0x40/0x90
[  285.378772]  ? kasan_enable_current+0x11/0x20
[  285.379469]  ? __pfx_raw_sendmsg+0x10/0x10
[  285.380137]  ? __sock_create+0x13e/0x270
[  285.380673]  ? __sys_socket+0xf3/0x180
[  285.381174]  ? __x64_sys_socket+0x3d/0x50
[  285.381725]  ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.382425]  ? __rcu_read_unlock+0x48/0x70
[  285.382975]  ? ip4_datagram_release_cb+0xd8/0x380
[  285.383608]  ? __pfx_ip4_datagram_release_cb+0x10/0x10
[  285.384295]  ? preempt_count_sub+0x14/0xc0
[  285.384844]  ? __list_del_entry_valid+0x76/0x140
[  285.385467]  ? _raw_spin_lock_bh+0x87/0xe0
[  285.386014]  ? __pfx__raw_spin_lock_bh+0x10/0x10
[  285.386645]  ? release_sock+0xa0/0xd0
[  285.387148]  ? preempt_count_sub+0x14/0xc0
[  285.387712]  ? freeze_secondary_cpus+0x348/0x3c0
[  285.388341]  ? aa_sk_perm+0x177/0x390
[  285.388856]  ? __pfx_aa_sk_perm+0x10/0x10
[  285.389441]  ? check_stack_object+0x22/0x70
[  285.390032]  ? inet_send_prepare+0x2f/0x120
[  285.390603]  ? __pfx_inet_sendmsg+0x10/0x10
[  285.391172]  sock_sendmsg+0xcc/0xe0
[  285.391667]  __sys_sendto+0x190/0x230
[  285.392168]  ? __pfx___sys_sendto+0x10/0x10
[  285.392727]  ? kvm_clock_get_cycles+0x14/0x30
[  285.393328]  ? set_normalized_timespec64+0x57/0x70
[  285.393980]  ? _raw_spin_unlock_irq+0x1b/0x40
[  285.394578]  ? __x64_sys_clock_gettime+0x11c/0x160
[  285.395225]  ? __pfx___x64_sys_clock_gettime+0x10/0x10
[  285.395908]  ? _copy_to_user+0x3e/0x60
[  285.396432]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.397086]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.397734]  ? do_syscall_64+0x71/0x90
[  285.398258]  __x64_sys_sendto+0x74/0x90
[  285.398786]  do_syscall_64+0x64/0x90
[  285.399273]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.399949]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.400605]  ? do_syscall_64+0x71/0x90
[  285.401124]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.401807] RIP: 0033:0x495726
[  285.402233] Code: ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 09
[  285.404683] RSP: 002b:00007ffcc25fb618 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[  285.405677] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 0000000000495726
[  285.406628] RDX: 0000000000000040 RSI: 0000000002518750 RDI: 0000000000000000
[  285.407565] RBP: 00000000005205ef R08: 00000000005f8838 R09: 000000000000001c
[  285.408523] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002517634
[  285.409460] R13: 00007ffcc25fb6f0 R14: 0000000000000003 R15: 0000000000000000
[  285.410403]  </TASK>
[  285.410704]
[  285.410929] Allocated by task 144:
[  285.411402]  kasan_save_stack+0x1e/0x40
[  285.411926]  kasan_set_track+0x21/0x30
[  285.412442]  __kasan_slab_alloc+0x55/0x70
[  285.412973]  kmem_cache_alloc_node+0x187/0x3d0
[  285.413567]  __alloc_skb+0x1b4/0x230
[  285.414060]  __ip_append_data+0x17f7/0x1b60
[  285.414633]  ip_append_data+0x97/0xf0
[  285.415144]  raw_sendmsg+0x5a8/0x12d0
[  285.415640]  sock_sendmsg+0xcc/0xe0
[  285.416117]  __sys_sendto+0x190/0x230
[  285.416626]  __x64_sys_sendto+0x74/0x90
[  285.417145]  do_syscall_64+0x64/0x90
[  285.417624]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.418306]
[  285.418531] Freed by task 144:
[  285.418960]  kasan_save_stack+0x1e/0x40
[  285.419469]  kasan_set_track+0x21/0x30
[  285.419988]  kasan_save_free_info+0x27/0x40
[  285.420556]  ____kasan_slab_free+0x109/0x1a0
[  285.421146]  kmem_cache_free+0x1c2/0x450
[  285.421680]  __netif_receive_skb_core+0x2ce/0x1870
[  285.422333]  __netif_receive_skb_one_core+0x97/0x140
[  285.423003]  process_backlog+0x100/0x2f0
[  285.423537]  __napi_poll+0x5c/0x2d0
[  285.424023]  net_rx_action+0x2be/0x560
[  285.424510]  __do_softirq+0x11b/0x3de
[  285.425034]
[  285.425254] The buggy address belongs to the object at ffff8880bad31280
[  285.425254]  which belongs to the cache skbuff_head_cache of size 224
[  285.426993] The buggy address is located 40 bytes inside of
[  285.426993]  freed 224-byte region [ffff8880bad31280, ffff8880bad31360)
[  285.428572]
[  285.428798] The buggy address belongs to the physical page:
[  285.429540] page:00000000f4b77674 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xbad31
[  285.430758] flags: 0x100000000000200(slab|node=0|zone=1)
[  285.431447] page_type: 0xffffffff()
[  285.431934] raw: 0100000000000200 ffff88810094a8c0 dead000000000122 0000000000000000
[  285.432757] raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
[  285.433562] page dumped because: kasan: bad access detected
[  285.434144]
[  285.434320] Memory state around the buggy address:
[  285.434828]  ffff8880bad31180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.435580]  ffff8880bad31200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.436264] >ffff8880bad31280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  285.436777]                                   ^
[  285.437106]  ffff8880bad31300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
[  285.437616]  ffff8880bad31380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.438126] ==================================================================
[  285.438662] Disabling lock debugging due to kernel taint

Fix this by:
1. Changing sch_plug's .peek handler to qdisc_peek_dequeued(), a
function compatible with non-work-conserving qdiscs
2. Checking the return value of qdisc_dequeue_peeked() in sch_qfq.

Fixes: 462dbc9 ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Reported-by: valis <sec@valis.email>
Signed-off-by: valis <sec@valis.email>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20230901162237.11525-1-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit 7962ef1 ]

In 3cb4d5e ("perf trace: Free syscall tp fields in
evsel->priv") it only was freeing if strcmp(evsel->tp_format->system,
"syscalls") returned zero, while the corresponding initialization of
evsel->priv was being performed if it was _not_ zero, i.e. if the tp
system wasn't 'syscalls'.

Just stop looking for that and free it if evsel->priv was set, which
should be equivalent.

Also use the pre-existing evsel_trace__delete() function.

This resolves these leaks, detected with:

  $ make EXTRA_CFLAGS="-fsanitize=address" BUILD_BPF_SKEL=1 CORESIGHT=1 O=/tmp/build/perf-tools-next -C tools/perf install-bin

  =================================================================
  ==481565==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f7343cba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x987966 in zalloc (/home/acme/bin/perf+0x987966)
      #2 0x52f9b9 in evsel_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:307
      #3 0x52f9b9 in evsel__syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:333
      #4 0x52f9b9 in evsel__init_raw_syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:458
      #5 0x52f9b9 in perf_evsel__raw_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:480
      #6 0x540e8b in trace__add_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3212
      #7 0x540e8b in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3891
      #8 0x540e8b in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5156
      #9 0x5ef262 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #10 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #11 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #12 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
      #13 0x7f7342c4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f7343cba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x987966 in zalloc (/home/acme/bin/perf+0x987966)
      #2 0x52f9b9 in evsel_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:307
      #3 0x52f9b9 in evsel__syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:333
      #4 0x52f9b9 in evsel__init_raw_syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:458
      #5 0x52f9b9 in perf_evsel__raw_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:480
      #6 0x540dd1 in trace__add_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3205
      #7 0x540dd1 in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3891
      #8 0x540dd1 in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5156
      #9 0x5ef262 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #10 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #11 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #12 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
      #13 0x7f7342c4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  SUMMARY: AddressSanitizer: 80 byte(s) leaked in 2 allocation(s).
  [root@quaco ~]#

With this we plug all leaks with "perf trace sleep 1".

Fixes: 3cb4d5e ("perf trace: Free syscall tp fields in evsel->priv")
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Link: https://lore.kernel.org/lkml/20230719202951.534582-5-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit ef23cb5 ]

While debugging a segfault on 'perf lock contention' without an
available perf.data file I noticed that it was basically calling:

	perf_session__delete(ERR_PTR(-1))

Resulting in:

  (gdb) run lock contention
  Starting program: /root/bin/perf lock contention
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  Initializing perf session failed

  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  2858		if (!session->auxtrace)
  (gdb) p session
  $1 = (struct perf_session *) 0xffffffffffffffff
  (gdb) bt
  #0  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  #1  0x000000000057bb4d in perf_session__delete (session=0xffffffffffffffff) at util/session.c:300
  #2  0x000000000047c421 in __cmd_contention (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2161
  #3  0x000000000047dc95 in cmd_lock (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2604
  #4  0x0000000000501466 in run_builtin (p=0xe597a8 <commands+552>, argc=2, argv=0x7fffffffe200) at perf.c:322
  #5  0x00000000005016d5 in handle_internal_command (argc=2, argv=0x7fffffffe200) at perf.c:375
  #6  0x0000000000501824 in run_argv (argcp=0x7fffffffe02c, argv=0x7fffffffe020) at perf.c:419
  #7  0x0000000000501b11 in main (argc=2, argv=0x7fffffffe200) at perf.c:535
  (gdb)

So just set it to NULL after using PTR_ERR(session) to decode the error
as perf_session__delete(NULL) is supported.

The same problem was found in 'perf top' after an audit of all
perf_session__new() failure handling.

Fixes: 6ef81c5 ("perf session: Return error code for perf_session__new() function on failure")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeremie Galarneau <jeremie.galarneau@efficios.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mukesh Ojha <mojha@codeaurora.org>
Cc: Nageswara R Sastry <rnsastry@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Shawn Landden <shawn@git.icu>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Link: https://lore.kernel.org/lkml/ZN4Q2rxxsL08A8rd@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit 8fc134f ]

When the plug qdisc is used as a class of the qfq qdisc it could trigger a
UAF. This issue can be reproduced with following commands:

  tc qdisc add dev lo root handle 1: qfq
  tc class add dev lo parent 1: classid 1:1 qfq weight 1 maxpkt 512
  tc qdisc add dev lo parent 1:1 handle 2: plug
  tc filter add dev lo parent 1: basic classid 1:1
  ping -c1 127.0.0.1

and boom:

[  285.353793] BUG: KASAN: slab-use-after-free in qfq_dequeue+0xa7/0x7f0
[  285.354910] Read of size 4 at addr ffff8880bad312a8 by task ping/144
[  285.355903]
[  285.356165] CPU: 1 PID: 144 Comm: ping Not tainted 6.5.0-rc3+ #4
[  285.357112] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
[  285.358376] Call Trace:
[  285.358773]  <IRQ>
[  285.359109]  dump_stack_lvl+0x44/0x60
[  285.359708]  print_address_description.constprop.0+0x2c/0x3c0
[  285.360611]  kasan_report+0x10c/0x120
[  285.361195]  ? qfq_dequeue+0xa7/0x7f0
[  285.361780]  qfq_dequeue+0xa7/0x7f0
[  285.362342]  __qdisc_run+0xf1/0x970
[  285.362903]  net_tx_action+0x28e/0x460
[  285.363502]  __do_softirq+0x11b/0x3de
[  285.364097]  do_softirq.part.0+0x72/0x90
[  285.364721]  </IRQ>
[  285.365072]  <TASK>
[  285.365422]  __local_bh_enable_ip+0x77/0x90
[  285.366079]  __dev_queue_xmit+0x95f/0x1550
[  285.366732]  ? __pfx_csum_and_copy_from_iter+0x10/0x10
[  285.367526]  ? __pfx___dev_queue_xmit+0x10/0x10
[  285.368259]  ? __build_skb_around+0x129/0x190
[  285.368960]  ? ip_generic_getfrag+0x12c/0x170
[  285.369653]  ? __pfx_ip_generic_getfrag+0x10/0x10
[  285.370390]  ? csum_partial+0x8/0x20
[  285.370961]  ? raw_getfrag+0xe5/0x140
[  285.371559]  ip_finish_output2+0x539/0xa40
[  285.372222]  ? __pfx_ip_finish_output2+0x10/0x10
[  285.372954]  ip_output+0x113/0x1e0
[  285.373512]  ? __pfx_ip_output+0x10/0x10
[  285.374130]  ? icmp_out_count+0x49/0x60
[  285.374739]  ? __pfx_ip_finish_output+0x10/0x10
[  285.375457]  ip_push_pending_frames+0xf3/0x100
[  285.376173]  raw_sendmsg+0xef5/0x12d0
[  285.376760]  ? do_syscall_64+0x40/0x90
[  285.377359]  ? __static_call_text_end+0x136578/0x136578
[  285.378173]  ? do_syscall_64+0x40/0x90
[  285.378772]  ? kasan_enable_current+0x11/0x20
[  285.379469]  ? __pfx_raw_sendmsg+0x10/0x10
[  285.380137]  ? __sock_create+0x13e/0x270
[  285.380673]  ? __sys_socket+0xf3/0x180
[  285.381174]  ? __x64_sys_socket+0x3d/0x50
[  285.381725]  ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.382425]  ? __rcu_read_unlock+0x48/0x70
[  285.382975]  ? ip4_datagram_release_cb+0xd8/0x380
[  285.383608]  ? __pfx_ip4_datagram_release_cb+0x10/0x10
[  285.384295]  ? preempt_count_sub+0x14/0xc0
[  285.384844]  ? __list_del_entry_valid+0x76/0x140
[  285.385467]  ? _raw_spin_lock_bh+0x87/0xe0
[  285.386014]  ? __pfx__raw_spin_lock_bh+0x10/0x10
[  285.386645]  ? release_sock+0xa0/0xd0
[  285.387148]  ? preempt_count_sub+0x14/0xc0
[  285.387712]  ? freeze_secondary_cpus+0x348/0x3c0
[  285.388341]  ? aa_sk_perm+0x177/0x390
[  285.388856]  ? __pfx_aa_sk_perm+0x10/0x10
[  285.389441]  ? check_stack_object+0x22/0x70
[  285.390032]  ? inet_send_prepare+0x2f/0x120
[  285.390603]  ? __pfx_inet_sendmsg+0x10/0x10
[  285.391172]  sock_sendmsg+0xcc/0xe0
[  285.391667]  __sys_sendto+0x190/0x230
[  285.392168]  ? __pfx___sys_sendto+0x10/0x10
[  285.392727]  ? kvm_clock_get_cycles+0x14/0x30
[  285.393328]  ? set_normalized_timespec64+0x57/0x70
[  285.393980]  ? _raw_spin_unlock_irq+0x1b/0x40
[  285.394578]  ? __x64_sys_clock_gettime+0x11c/0x160
[  285.395225]  ? __pfx___x64_sys_clock_gettime+0x10/0x10
[  285.395908]  ? _copy_to_user+0x3e/0x60
[  285.396432]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.397086]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.397734]  ? do_syscall_64+0x71/0x90
[  285.398258]  __x64_sys_sendto+0x74/0x90
[  285.398786]  do_syscall_64+0x64/0x90
[  285.399273]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.399949]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.400605]  ? do_syscall_64+0x71/0x90
[  285.401124]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.401807] RIP: 0033:0x495726
[  285.402233] Code: ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 09
[  285.404683] RSP: 002b:00007ffcc25fb618 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[  285.405677] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 0000000000495726
[  285.406628] RDX: 0000000000000040 RSI: 0000000002518750 RDI: 0000000000000000
[  285.407565] RBP: 00000000005205ef R08: 00000000005f8838 R09: 000000000000001c
[  285.408523] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002517634
[  285.409460] R13: 00007ffcc25fb6f0 R14: 0000000000000003 R15: 0000000000000000
[  285.410403]  </TASK>
[  285.410704]
[  285.410929] Allocated by task 144:
[  285.411402]  kasan_save_stack+0x1e/0x40
[  285.411926]  kasan_set_track+0x21/0x30
[  285.412442]  __kasan_slab_alloc+0x55/0x70
[  285.412973]  kmem_cache_alloc_node+0x187/0x3d0
[  285.413567]  __alloc_skb+0x1b4/0x230
[  285.414060]  __ip_append_data+0x17f7/0x1b60
[  285.414633]  ip_append_data+0x97/0xf0
[  285.415144]  raw_sendmsg+0x5a8/0x12d0
[  285.415640]  sock_sendmsg+0xcc/0xe0
[  285.416117]  __sys_sendto+0x190/0x230
[  285.416626]  __x64_sys_sendto+0x74/0x90
[  285.417145]  do_syscall_64+0x64/0x90
[  285.417624]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.418306]
[  285.418531] Freed by task 144:
[  285.418960]  kasan_save_stack+0x1e/0x40
[  285.419469]  kasan_set_track+0x21/0x30
[  285.419988]  kasan_save_free_info+0x27/0x40
[  285.420556]  ____kasan_slab_free+0x109/0x1a0
[  285.421146]  kmem_cache_free+0x1c2/0x450
[  285.421680]  __netif_receive_skb_core+0x2ce/0x1870
[  285.422333]  __netif_receive_skb_one_core+0x97/0x140
[  285.423003]  process_backlog+0x100/0x2f0
[  285.423537]  __napi_poll+0x5c/0x2d0
[  285.424023]  net_rx_action+0x2be/0x560
[  285.424510]  __do_softirq+0x11b/0x3de
[  285.425034]
[  285.425254] The buggy address belongs to the object at ffff8880bad31280
[  285.425254]  which belongs to the cache skbuff_head_cache of size 224
[  285.426993] The buggy address is located 40 bytes inside of
[  285.426993]  freed 224-byte region [ffff8880bad31280, ffff8880bad31360)
[  285.428572]
[  285.428798] The buggy address belongs to the physical page:
[  285.429540] page:00000000f4b77674 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xbad31
[  285.430758] flags: 0x100000000000200(slab|node=0|zone=1)
[  285.431447] page_type: 0xffffffff()
[  285.431934] raw: 0100000000000200 ffff88810094a8c0 dead000000000122 0000000000000000
[  285.432757] raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
[  285.433562] page dumped because: kasan: bad access detected
[  285.434144]
[  285.434320] Memory state around the buggy address:
[  285.434828]  ffff8880bad31180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.435580]  ffff8880bad31200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.436264] >ffff8880bad31280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  285.436777]                                   ^
[  285.437106]  ffff8880bad31300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
[  285.437616]  ffff8880bad31380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.438126] ==================================================================
[  285.438662] Disabling lock debugging due to kernel taint

Fix this by:
1. Changing sch_plug's .peek handler to qdisc_peek_dequeued(), a
function compatible with non-work-conserving qdiscs
2. Checking the return value of qdisc_dequeue_peeked() in sch_qfq.

Fixes: 462dbc9 ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Reported-by: valis <sec@valis.email>
Signed-off-by: valis <sec@valis.email>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20230901162237.11525-1-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit 7962ef1 ]

In 3cb4d5e ("perf trace: Free syscall tp fields in
evsel->priv") it only was freeing if strcmp(evsel->tp_format->system,
"syscalls") returned zero, while the corresponding initialization of
evsel->priv was being performed if it was _not_ zero, i.e. if the tp
system wasn't 'syscalls'.

Just stop looking for that and free it if evsel->priv was set, which
should be equivalent.

Also use the pre-existing evsel_trace__delete() function.

This resolves these leaks, detected with:

  $ make EXTRA_CFLAGS="-fsanitize=address" BUILD_BPF_SKEL=1 CORESIGHT=1 O=/tmp/build/perf-tools-next -C tools/perf install-bin

  =================================================================
  ==481565==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f7343cba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x987966 in zalloc (/home/acme/bin/perf+0x987966)
      #2 0x52f9b9 in evsel_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:307
      #3 0x52f9b9 in evsel__syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:333
      #4 0x52f9b9 in evsel__init_raw_syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:458
      #5 0x52f9b9 in perf_evsel__raw_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:480
      #6 0x540e8b in trace__add_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3212
      #7 0x540e8b in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3891
      #8 0x540e8b in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5156
      #9 0x5ef262 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #10 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #11 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #12 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
      #13 0x7f7342c4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f7343cba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x987966 in zalloc (/home/acme/bin/perf+0x987966)
      #2 0x52f9b9 in evsel_trace__new /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:307
      #3 0x52f9b9 in evsel__syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:333
      #4 0x52f9b9 in evsel__init_raw_syscall_tp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:458
      #5 0x52f9b9 in perf_evsel__raw_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:480
      #6 0x540dd1 in trace__add_syscall_newtp /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3205
      #7 0x540dd1 in trace__run /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:3891
      #8 0x540dd1 in cmd_trace /home/acme/git/perf-tools-next/tools/perf/builtin-trace.c:5156
      #9 0x5ef262 in run_builtin /home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #10 0x4196da in handle_internal_command /home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #11 0x4196da in run_argv /home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #12 0x4196da in main /home/acme/git/perf-tools-next/tools/perf/perf.c:537
      #13 0x7f7342c4a50f in __libc_start_call_main (/lib64/libc.so.6+0x2750f)

  SUMMARY: AddressSanitizer: 80 byte(s) leaked in 2 allocation(s).
  [root@quaco ~]#

With this we plug all leaks with "perf trace sleep 1".

Fixes: 3cb4d5e ("perf trace: Free syscall tp fields in evsel->priv")
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Link: https://lore.kernel.org/lkml/20230719202951.534582-5-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit ef23cb5 ]

While debugging a segfault on 'perf lock contention' without an
available perf.data file I noticed that it was basically calling:

	perf_session__delete(ERR_PTR(-1))

Resulting in:

  (gdb) run lock contention
  Starting program: /root/bin/perf lock contention
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  Initializing perf session failed

  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  2858		if (!session->auxtrace)
  (gdb) p session
  $1 = (struct perf_session *) 0xffffffffffffffff
  (gdb) bt
  #0  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  #1  0x000000000057bb4d in perf_session__delete (session=0xffffffffffffffff) at util/session.c:300
  #2  0x000000000047c421 in __cmd_contention (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2161
  #3  0x000000000047dc95 in cmd_lock (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2604
  #4  0x0000000000501466 in run_builtin (p=0xe597a8 <commands+552>, argc=2, argv=0x7fffffffe200) at perf.c:322
  #5  0x00000000005016d5 in handle_internal_command (argc=2, argv=0x7fffffffe200) at perf.c:375
  #6  0x0000000000501824 in run_argv (argcp=0x7fffffffe02c, argv=0x7fffffffe020) at perf.c:419
  #7  0x0000000000501b11 in main (argc=2, argv=0x7fffffffe200) at perf.c:535
  (gdb)

So just set it to NULL after using PTR_ERR(session) to decode the error
as perf_session__delete(NULL) is supported.

The same problem was found in 'perf top' after an audit of all
perf_session__new() failure handling.

Fixes: 6ef81c5 ("perf session: Return error code for perf_session__new() function on failure")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeremie Galarneau <jeremie.galarneau@efficios.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mukesh Ojha <mojha@codeaurora.org>
Cc: Nageswara R Sastry <rnsastry@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Shawn Landden <shawn@git.icu>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Link: https://lore.kernel.org/lkml/ZN4Q2rxxsL08A8rd@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit abaf1e0 ]

While debugging a segfault on 'perf lock contention' without an
available perf.data file I noticed that it was basically calling:

	perf_session__delete(ERR_PTR(-1))

Resulting in:

  (gdb) run lock contention
  Starting program: /root/bin/perf lock contention
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  Initializing perf session failed

  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  2858		if (!session->auxtrace)
  (gdb) p session
  $1 = (struct perf_session *) 0xffffffffffffffff
  (gdb) bt
  #0  0x00000000005e7515 in auxtrace__free (session=0xffffffffffffffff) at util/auxtrace.c:2858
  #1  0x000000000057bb4d in perf_session__delete (session=0xffffffffffffffff) at util/session.c:300
  #2  0x000000000047c421 in __cmd_contention (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2161
  #3  0x000000000047dc95 in cmd_lock (argc=0, argv=0x7fffffffe200) at builtin-lock.c:2604
  #4  0x0000000000501466 in run_builtin (p=0xe597a8 <commands+552>, argc=2, argv=0x7fffffffe200) at perf.c:322
  #5  0x00000000005016d5 in handle_internal_command (argc=2, argv=0x7fffffffe200) at perf.c:375
  #6  0x0000000000501824 in run_argv (argcp=0x7fffffffe02c, argv=0x7fffffffe020) at perf.c:419
  #7  0x0000000000501b11 in main (argc=2, argv=0x7fffffffe200) at perf.c:535
  (gdb)

So just set it to NULL after using PTR_ERR(session) to decode the error
as perf_session__delete(NULL) is supported.

Fixes: eef4fee ("perf lock: Dynamically allocate lockhash_table")
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Ross Zwisler <zwisler@chromium.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/lkml/ZN4R1AYfsD2J8lRs@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 20, 2023
[ Upstream commit 8fc134f ]

When the plug qdisc is used as a class of the qfq qdisc it could trigger a
UAF. This issue can be reproduced with following commands:

  tc qdisc add dev lo root handle 1: qfq
  tc class add dev lo parent 1: classid 1:1 qfq weight 1 maxpkt 512
  tc qdisc add dev lo parent 1:1 handle 2: plug
  tc filter add dev lo parent 1: basic classid 1:1
  ping -c1 127.0.0.1

and boom:

[  285.353793] BUG: KASAN: slab-use-after-free in qfq_dequeue+0xa7/0x7f0
[  285.354910] Read of size 4 at addr ffff8880bad312a8 by task ping/144
[  285.355903]
[  285.356165] CPU: 1 PID: 144 Comm: ping Not tainted 6.5.0-rc3+ #4
[  285.357112] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
[  285.358376] Call Trace:
[  285.358773]  <IRQ>
[  285.359109]  dump_stack_lvl+0x44/0x60
[  285.359708]  print_address_description.constprop.0+0x2c/0x3c0
[  285.360611]  kasan_report+0x10c/0x120
[  285.361195]  ? qfq_dequeue+0xa7/0x7f0
[  285.361780]  qfq_dequeue+0xa7/0x7f0
[  285.362342]  __qdisc_run+0xf1/0x970
[  285.362903]  net_tx_action+0x28e/0x460
[  285.363502]  __do_softirq+0x11b/0x3de
[  285.364097]  do_softirq.part.0+0x72/0x90
[  285.364721]  </IRQ>
[  285.365072]  <TASK>
[  285.365422]  __local_bh_enable_ip+0x77/0x90
[  285.366079]  __dev_queue_xmit+0x95f/0x1550
[  285.366732]  ? __pfx_csum_and_copy_from_iter+0x10/0x10
[  285.367526]  ? __pfx___dev_queue_xmit+0x10/0x10
[  285.368259]  ? __build_skb_around+0x129/0x190
[  285.368960]  ? ip_generic_getfrag+0x12c/0x170
[  285.369653]  ? __pfx_ip_generic_getfrag+0x10/0x10
[  285.370390]  ? csum_partial+0x8/0x20
[  285.370961]  ? raw_getfrag+0xe5/0x140
[  285.371559]  ip_finish_output2+0x539/0xa40
[  285.372222]  ? __pfx_ip_finish_output2+0x10/0x10
[  285.372954]  ip_output+0x113/0x1e0
[  285.373512]  ? __pfx_ip_output+0x10/0x10
[  285.374130]  ? icmp_out_count+0x49/0x60
[  285.374739]  ? __pfx_ip_finish_output+0x10/0x10
[  285.375457]  ip_push_pending_frames+0xf3/0x100
[  285.376173]  raw_sendmsg+0xef5/0x12d0
[  285.376760]  ? do_syscall_64+0x40/0x90
[  285.377359]  ? __static_call_text_end+0x136578/0x136578
[  285.378173]  ? do_syscall_64+0x40/0x90
[  285.378772]  ? kasan_enable_current+0x11/0x20
[  285.379469]  ? __pfx_raw_sendmsg+0x10/0x10
[  285.380137]  ? __sock_create+0x13e/0x270
[  285.380673]  ? __sys_socket+0xf3/0x180
[  285.381174]  ? __x64_sys_socket+0x3d/0x50
[  285.381725]  ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.382425]  ? __rcu_read_unlock+0x48/0x70
[  285.382975]  ? ip4_datagram_release_cb+0xd8/0x380
[  285.383608]  ? __pfx_ip4_datagram_release_cb+0x10/0x10
[  285.384295]  ? preempt_count_sub+0x14/0xc0
[  285.384844]  ? __list_del_entry_valid+0x76/0x140
[  285.385467]  ? _raw_spin_lock_bh+0x87/0xe0
[  285.386014]  ? __pfx__raw_spin_lock_bh+0x10/0x10
[  285.386645]  ? release_sock+0xa0/0xd0
[  285.387148]  ? preempt_count_sub+0x14/0xc0
[  285.387712]  ? freeze_secondary_cpus+0x348/0x3c0
[  285.388341]  ? aa_sk_perm+0x177/0x390
[  285.388856]  ? __pfx_aa_sk_perm+0x10/0x10
[  285.389441]  ? check_stack_object+0x22/0x70
[  285.390032]  ? inet_send_prepare+0x2f/0x120
[  285.390603]  ? __pfx_inet_sendmsg+0x10/0x10
[  285.391172]  sock_sendmsg+0xcc/0xe0
[  285.391667]  __sys_sendto+0x190/0x230
[  285.392168]  ? __pfx___sys_sendto+0x10/0x10
[  285.392727]  ? kvm_clock_get_cycles+0x14/0x30
[  285.393328]  ? set_normalized_timespec64+0x57/0x70
[  285.393980]  ? _raw_spin_unlock_irq+0x1b/0x40
[  285.394578]  ? __x64_sys_clock_gettime+0x11c/0x160
[  285.395225]  ? __pfx___x64_sys_clock_gettime+0x10/0x10
[  285.395908]  ? _copy_to_user+0x3e/0x60
[  285.396432]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.397086]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.397734]  ? do_syscall_64+0x71/0x90
[  285.398258]  __x64_sys_sendto+0x74/0x90
[  285.398786]  do_syscall_64+0x64/0x90
[  285.399273]  ? exit_to_user_mode_prepare+0x1a/0x120
[  285.399949]  ? syscall_exit_to_user_mode+0x22/0x50
[  285.400605]  ? do_syscall_64+0x71/0x90
[  285.401124]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.401807] RIP: 0033:0x495726
[  285.402233] Code: ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 09
[  285.404683] RSP: 002b:00007ffcc25fb618 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[  285.405677] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 0000000000495726
[  285.406628] RDX: 0000000000000040 RSI: 0000000002518750 RDI: 0000000000000000
[  285.407565] RBP: 00000000005205ef R08: 00000000005f8838 R09: 000000000000001c
[  285.408523] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000002517634
[  285.409460] R13: 00007ffcc25fb6f0 R14: 0000000000000003 R15: 0000000000000000
[  285.410403]  </TASK>
[  285.410704]
[  285.410929] Allocated by task 144:
[  285.411402]  kasan_save_stack+0x1e/0x40
[  285.411926]  kasan_set_track+0x21/0x30
[  285.412442]  __kasan_slab_alloc+0x55/0x70
[  285.412973]  kmem_cache_alloc_node+0x187/0x3d0
[  285.413567]  __alloc_skb+0x1b4/0x230
[  285.414060]  __ip_append_data+0x17f7/0x1b60
[  285.414633]  ip_append_data+0x97/0xf0
[  285.415144]  raw_sendmsg+0x5a8/0x12d0
[  285.415640]  sock_sendmsg+0xcc/0xe0
[  285.416117]  __sys_sendto+0x190/0x230
[  285.416626]  __x64_sys_sendto+0x74/0x90
[  285.417145]  do_syscall_64+0x64/0x90
[  285.417624]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[  285.418306]
[  285.418531] Freed by task 144:
[  285.418960]  kasan_save_stack+0x1e/0x40
[  285.419469]  kasan_set_track+0x21/0x30
[  285.419988]  kasan_save_free_info+0x27/0x40
[  285.420556]  ____kasan_slab_free+0x109/0x1a0
[  285.421146]  kmem_cache_free+0x1c2/0x450
[  285.421680]  __netif_receive_skb_core+0x2ce/0x1870
[  285.422333]  __netif_receive_skb_one_core+0x97/0x140
[  285.423003]  process_backlog+0x100/0x2f0
[  285.423537]  __napi_poll+0x5c/0x2d0
[  285.424023]  net_rx_action+0x2be/0x560
[  285.424510]  __do_softirq+0x11b/0x3de
[  285.425034]
[  285.425254] The buggy address belongs to the object at ffff8880bad31280
[  285.425254]  which belongs to the cache skbuff_head_cache of size 224
[  285.426993] The buggy address is located 40 bytes inside of
[  285.426993]  freed 224-byte region [ffff8880bad31280, ffff8880bad31360)
[  285.428572]
[  285.428798] The buggy address belongs to the physical page:
[  285.429540] page:00000000f4b77674 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xbad31
[  285.430758] flags: 0x100000000000200(slab|node=0|zone=1)
[  285.431447] page_type: 0xffffffff()
[  285.431934] raw: 0100000000000200 ffff88810094a8c0 dead000000000122 0000000000000000
[  285.432757] raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
[  285.433562] page dumped because: kasan: bad access detected
[  285.434144]
[  285.434320] Memory state around the buggy address:
[  285.434828]  ffff8880bad31180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.435580]  ffff8880bad31200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.436264] >ffff8880bad31280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  285.436777]                                   ^
[  285.437106]  ffff8880bad31300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
[  285.437616]  ffff8880bad31380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  285.438126] ==================================================================
[  285.438662] Disabling lock debugging due to kernel taint

Fix this by:
1. Changing sch_plug's .peek handler to qdisc_peek_dequeued(), a
function compatible with non-work-conserving qdiscs
2. Checking the return value of qdisc_dequeue_peeked() in sch_qfq.

Fixes: 462dbc9 ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Reported-by: valis <sec@valis.email>
Signed-off-by: valis <sec@valis.email>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20230901162237.11525-1-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 24, 2023
[ Upstream commit af42269 ]

For cases where icc_bw_set() can be called in callbaths that could
deadlock against shrinker/reclaim, such as runpm resume, we need to
decouple the icc locking.  Introduce a new icc_bw_lock for cases where
we need to serialize bw aggregation and update to decouple that from
paths that require memory allocation such as node/link creation/
destruction.

Fixes this lockdep splat:

   ======================================================
   WARNING: possible circular locking dependency detected
   6.2.0-rc8-debug+ #554 Not tainted
   ------------------------------------------------------
   ring0/132 is trying to acquire lock:
   ffffff80871916d0 (&gmu->lock){+.+.}-{3:3}, at: a6xx_pm_resume+0xf0/0x234

   but task is already holding lock:
   ffffffdb5aee57e8 (dma_fence_map){++++}-{0:0}, at: msm_job_run+0x68/0x150

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #4 (dma_fence_map){++++}-{0:0}:
          __dma_fence_might_wait+0x74/0xc0
          dma_resv_lockdep+0x1f4/0x2f4
          do_one_initcall+0x104/0x2bc
          kernel_init_freeable+0x344/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}:
          fs_reclaim_acquire+0x80/0xa8
          slab_pre_alloc_hook.constprop.0+0x40/0x25c
          __kmem_cache_alloc_node+0x60/0x1cc
          __kmalloc+0xd8/0x100
          topology_parse_cpu_capacity+0x8c/0x178
          get_cpu_for_node+0x88/0xc4
          parse_cluster+0x1b0/0x28c
          parse_cluster+0x8c/0x28c
          init_cpu_topology+0x168/0x188
          smp_prepare_cpus+0x24/0xf8
          kernel_init_freeable+0x18c/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #2 (fs_reclaim){+.+.}-{0:0}:
          __fs_reclaim_acquire+0x3c/0x48
          fs_reclaim_acquire+0x54/0xa8
          slab_pre_alloc_hook.constprop.0+0x40/0x25c
          __kmem_cache_alloc_node+0x60/0x1cc
          __kmalloc+0xd8/0x100
          kzalloc.constprop.0+0x14/0x20
          icc_node_create_nolock+0x4c/0xc4
          icc_node_create+0x38/0x58
          qcom_icc_rpmh_probe+0x1b8/0x248
          platform_probe+0x70/0xc4
          really_probe+0x158/0x290
          __driver_probe_device+0xc8/0xe0
          driver_probe_device+0x44/0x100
          __driver_attach+0xf8/0x108
          bus_for_each_dev+0x78/0xc4
          driver_attach+0x2c/0x38
          bus_add_driver+0xd0/0x1d8
          driver_register+0xbc/0xf8
          __platform_driver_register+0x30/0x3c
          qnoc_driver_init+0x24/0x30
          do_one_initcall+0x104/0x2bc
          kernel_init_freeable+0x344/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #1 (icc_lock){+.+.}-{3:3}:
          __mutex_lock+0xcc/0x3c8
          mutex_lock_nested+0x30/0x44
          icc_set_bw+0x88/0x2b4
          _set_opp_bw+0x8c/0xd8
          _set_opp+0x19c/0x300
          dev_pm_opp_set_opp+0x84/0x94
          a6xx_gmu_resume+0x18c/0x804
          a6xx_pm_resume+0xf8/0x234
          adreno_runtime_resume+0x2c/0x38
          pm_generic_runtime_resume+0x30/0x44
          __rpm_callback+0x15c/0x174
          rpm_callback+0x78/0x7c
          rpm_resume+0x318/0x524
          __pm_runtime_resume+0x78/0xbc
          adreno_load_gpu+0xc4/0x17c
          msm_open+0x50/0x120
          drm_file_alloc+0x17c/0x228
          drm_open_helper+0x74/0x118
          drm_open+0xa0/0x144
          drm_stub_open+0xd4/0xe4
          chrdev_open+0x1b8/0x1e4
          do_dentry_open+0x2f8/0x38c
          vfs_open+0x34/0x40
          path_openat+0x64c/0x7b4
          do_filp_open+0x54/0xc4
          do_sys_openat2+0x9c/0x100
          do_sys_open+0x50/0x7c
          __arm64_sys_openat+0x28/0x34
          invoke_syscall+0x8c/0x128
          el0_svc_common.constprop.0+0xa0/0x11c
          do_el0_svc+0xac/0xbc
          el0_svc+0x48/0xa0
          el0t_64_sync_handler+0xac/0x13c
          el0t_64_sync+0x190/0x194

   -> #0 (&gmu->lock){+.+.}-{3:3}:
          __lock_acquire+0xe00/0x1060
          lock_acquire+0x1e0/0x2f8
          __mutex_lock+0xcc/0x3c8
          mutex_lock_nested+0x30/0x44
          a6xx_pm_resume+0xf0/0x234
          adreno_runtime_resume+0x2c/0x38
          pm_generic_runtime_resume+0x30/0x44
          __rpm_callback+0x15c/0x174
          rpm_callback+0x78/0x7c
          rpm_resume+0x318/0x524
          __pm_runtime_resume+0x78/0xbc
          pm_runtime_get_sync.isra.0+0x14/0x20
          msm_gpu_submit+0x58/0x178
          msm_job_run+0x78/0x150
          drm_sched_main+0x290/0x370
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   other info that might help us debug this:

   Chain exists of:
     &gmu->lock --> mmu_notifier_invalidate_range_start --> dma_fence_map

    Possible unsafe locking scenario:

          CPU0                    CPU1
          ----                    ----
     lock(dma_fence_map);
                                  lock(mmu_notifier_invalidate_range_start);
                                  lock(dma_fence_map);
     lock(&gmu->lock);

    *** DEADLOCK ***

   2 locks held by ring0/132:
    #0: ffffff8087191170 (&gpu->lock){+.+.}-{3:3}, at: msm_job_run+0x64/0x150
    #1: ffffffdb5aee57e8 (dma_fence_map){++++}-{0:0}, at: msm_job_run+0x68/0x150

   stack backtrace:
   CPU: 7 PID: 132 Comm: ring0 Not tainted 6.2.0-rc8-debug+ #554
   Hardware name: Google Lazor (rev1 - 2) with LTE (DT)
   Call trace:
    dump_backtrace.part.0+0xb4/0xf8
    show_stack+0x20/0x38
    dump_stack_lvl+0x9c/0xd0
    dump_stack+0x18/0x34
    print_circular_bug+0x1b4/0x1f0
    check_noncircular+0x78/0xac
    __lock_acquire+0xe00/0x1060
    lock_acquire+0x1e0/0x2f8
    __mutex_lock+0xcc/0x3c8
    mutex_lock_nested+0x30/0x44
    a6xx_pm_resume+0xf0/0x234
    adreno_runtime_resume+0x2c/0x38
    pm_generic_runtime_resume+0x30/0x44
    __rpm_callback+0x15c/0x174
    rpm_callback+0x78/0x7c
    rpm_resume+0x318/0x524
    __pm_runtime_resume+0x78/0xbc
    pm_runtime_get_sync.isra.0+0x14/0x20
    msm_gpu_submit+0x58/0x178
    msm_job_run+0x78/0x150
    drm_sched_main+0x290/0x370
    kthread+0xf0/0x100
    ret_from_fork+0x10/0x20

Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20230807171148.210181-7-robdclark@gmail.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 24, 2023
[ Upstream commit af42269 ]

For cases where icc_bw_set() can be called in callbaths that could
deadlock against shrinker/reclaim, such as runpm resume, we need to
decouple the icc locking.  Introduce a new icc_bw_lock for cases where
we need to serialize bw aggregation and update to decouple that from
paths that require memory allocation such as node/link creation/
destruction.

Fixes this lockdep splat:

   ======================================================
   WARNING: possible circular locking dependency detected
   6.2.0-rc8-debug+ #554 Not tainted
   ------------------------------------------------------
   ring0/132 is trying to acquire lock:
   ffffff80871916d0 (&gmu->lock){+.+.}-{3:3}, at: a6xx_pm_resume+0xf0/0x234

   but task is already holding lock:
   ffffffdb5aee57e8 (dma_fence_map){++++}-{0:0}, at: msm_job_run+0x68/0x150

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #4 (dma_fence_map){++++}-{0:0}:
          __dma_fence_might_wait+0x74/0xc0
          dma_resv_lockdep+0x1f4/0x2f4
          do_one_initcall+0x104/0x2bc
          kernel_init_freeable+0x344/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}:
          fs_reclaim_acquire+0x80/0xa8
          slab_pre_alloc_hook.constprop.0+0x40/0x25c
          __kmem_cache_alloc_node+0x60/0x1cc
          __kmalloc+0xd8/0x100
          topology_parse_cpu_capacity+0x8c/0x178
          get_cpu_for_node+0x88/0xc4
          parse_cluster+0x1b0/0x28c
          parse_cluster+0x8c/0x28c
          init_cpu_topology+0x168/0x188
          smp_prepare_cpus+0x24/0xf8
          kernel_init_freeable+0x18c/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #2 (fs_reclaim){+.+.}-{0:0}:
          __fs_reclaim_acquire+0x3c/0x48
          fs_reclaim_acquire+0x54/0xa8
          slab_pre_alloc_hook.constprop.0+0x40/0x25c
          __kmem_cache_alloc_node+0x60/0x1cc
          __kmalloc+0xd8/0x100
          kzalloc.constprop.0+0x14/0x20
          icc_node_create_nolock+0x4c/0xc4
          icc_node_create+0x38/0x58
          qcom_icc_rpmh_probe+0x1b8/0x248
          platform_probe+0x70/0xc4
          really_probe+0x158/0x290
          __driver_probe_device+0xc8/0xe0
          driver_probe_device+0x44/0x100
          __driver_attach+0xf8/0x108
          bus_for_each_dev+0x78/0xc4
          driver_attach+0x2c/0x38
          bus_add_driver+0xd0/0x1d8
          driver_register+0xbc/0xf8
          __platform_driver_register+0x30/0x3c
          qnoc_driver_init+0x24/0x30
          do_one_initcall+0x104/0x2bc
          kernel_init_freeable+0x344/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #1 (icc_lock){+.+.}-{3:3}:
          __mutex_lock+0xcc/0x3c8
          mutex_lock_nested+0x30/0x44
          icc_set_bw+0x88/0x2b4
          _set_opp_bw+0x8c/0xd8
          _set_opp+0x19c/0x300
          dev_pm_opp_set_opp+0x84/0x94
          a6xx_gmu_resume+0x18c/0x804
          a6xx_pm_resume+0xf8/0x234
          adreno_runtime_resume+0x2c/0x38
          pm_generic_runtime_resume+0x30/0x44
          __rpm_callback+0x15c/0x174
          rpm_callback+0x78/0x7c
          rpm_resume+0x318/0x524
          __pm_runtime_resume+0x78/0xbc
          adreno_load_gpu+0xc4/0x17c
          msm_open+0x50/0x120
          drm_file_alloc+0x17c/0x228
          drm_open_helper+0x74/0x118
          drm_open+0xa0/0x144
          drm_stub_open+0xd4/0xe4
          chrdev_open+0x1b8/0x1e4
          do_dentry_open+0x2f8/0x38c
          vfs_open+0x34/0x40
          path_openat+0x64c/0x7b4
          do_filp_open+0x54/0xc4
          do_sys_openat2+0x9c/0x100
          do_sys_open+0x50/0x7c
          __arm64_sys_openat+0x28/0x34
          invoke_syscall+0x8c/0x128
          el0_svc_common.constprop.0+0xa0/0x11c
          do_el0_svc+0xac/0xbc
          el0_svc+0x48/0xa0
          el0t_64_sync_handler+0xac/0x13c
          el0t_64_sync+0x190/0x194

   -> #0 (&gmu->lock){+.+.}-{3:3}:
          __lock_acquire+0xe00/0x1060
          lock_acquire+0x1e0/0x2f8
          __mutex_lock+0xcc/0x3c8
          mutex_lock_nested+0x30/0x44
          a6xx_pm_resume+0xf0/0x234
          adreno_runtime_resume+0x2c/0x38
          pm_generic_runtime_resume+0x30/0x44
          __rpm_callback+0x15c/0x174
          rpm_callback+0x78/0x7c
          rpm_resume+0x318/0x524
          __pm_runtime_resume+0x78/0xbc
          pm_runtime_get_sync.isra.0+0x14/0x20
          msm_gpu_submit+0x58/0x178
          msm_job_run+0x78/0x150
          drm_sched_main+0x290/0x370
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   other info that might help us debug this:

   Chain exists of:
     &gmu->lock --> mmu_notifier_invalidate_range_start --> dma_fence_map

    Possible unsafe locking scenario:

          CPU0                    CPU1
          ----                    ----
     lock(dma_fence_map);
                                  lock(mmu_notifier_invalidate_range_start);
                                  lock(dma_fence_map);
     lock(&gmu->lock);

    *** DEADLOCK ***

   2 locks held by ring0/132:
    #0: ffffff8087191170 (&gpu->lock){+.+.}-{3:3}, at: msm_job_run+0x64/0x150
    #1: ffffffdb5aee57e8 (dma_fence_map){++++}-{0:0}, at: msm_job_run+0x68/0x150

   stack backtrace:
   CPU: 7 PID: 132 Comm: ring0 Not tainted 6.2.0-rc8-debug+ #554
   Hardware name: Google Lazor (rev1 - 2) with LTE (DT)
   Call trace:
    dump_backtrace.part.0+0xb4/0xf8
    show_stack+0x20/0x38
    dump_stack_lvl+0x9c/0xd0
    dump_stack+0x18/0x34
    print_circular_bug+0x1b4/0x1f0
    check_noncircular+0x78/0xac
    __lock_acquire+0xe00/0x1060
    lock_acquire+0x1e0/0x2f8
    __mutex_lock+0xcc/0x3c8
    mutex_lock_nested+0x30/0x44
    a6xx_pm_resume+0xf0/0x234
    adreno_runtime_resume+0x2c/0x38
    pm_generic_runtime_resume+0x30/0x44
    __rpm_callback+0x15c/0x174
    rpm_callback+0x78/0x7c
    rpm_resume+0x318/0x524
    __pm_runtime_resume+0x78/0xbc
    pm_runtime_get_sync.isra.0+0x14/0x20
    msm_gpu_submit+0x58/0x178
    msm_job_run+0x78/0x150
    drm_sched_main+0x290/0x370
    kthread+0xf0/0x100
    ret_from_fork+0x10/0x20

Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20230807171148.210181-7-robdclark@gmail.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 24, 2023
[ Upstream commit af42269 ]

For cases where icc_bw_set() can be called in callbaths that could
deadlock against shrinker/reclaim, such as runpm resume, we need to
decouple the icc locking.  Introduce a new icc_bw_lock for cases where
we need to serialize bw aggregation and update to decouple that from
paths that require memory allocation such as node/link creation/
destruction.

Fixes this lockdep splat:

   ======================================================
   WARNING: possible circular locking dependency detected
   6.2.0-rc8-debug+ #554 Not tainted
   ------------------------------------------------------
   ring0/132 is trying to acquire lock:
   ffffff80871916d0 (&gmu->lock){+.+.}-{3:3}, at: a6xx_pm_resume+0xf0/0x234

   but task is already holding lock:
   ffffffdb5aee57e8 (dma_fence_map){++++}-{0:0}, at: msm_job_run+0x68/0x150

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #4 (dma_fence_map){++++}-{0:0}:
          __dma_fence_might_wait+0x74/0xc0
          dma_resv_lockdep+0x1f4/0x2f4
          do_one_initcall+0x104/0x2bc
          kernel_init_freeable+0x344/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}:
          fs_reclaim_acquire+0x80/0xa8
          slab_pre_alloc_hook.constprop.0+0x40/0x25c
          __kmem_cache_alloc_node+0x60/0x1cc
          __kmalloc+0xd8/0x100
          topology_parse_cpu_capacity+0x8c/0x178
          get_cpu_for_node+0x88/0xc4
          parse_cluster+0x1b0/0x28c
          parse_cluster+0x8c/0x28c
          init_cpu_topology+0x168/0x188
          smp_prepare_cpus+0x24/0xf8
          kernel_init_freeable+0x18c/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #2 (fs_reclaim){+.+.}-{0:0}:
          __fs_reclaim_acquire+0x3c/0x48
          fs_reclaim_acquire+0x54/0xa8
          slab_pre_alloc_hook.constprop.0+0x40/0x25c
          __kmem_cache_alloc_node+0x60/0x1cc
          __kmalloc+0xd8/0x100
          kzalloc.constprop.0+0x14/0x20
          icc_node_create_nolock+0x4c/0xc4
          icc_node_create+0x38/0x58
          qcom_icc_rpmh_probe+0x1b8/0x248
          platform_probe+0x70/0xc4
          really_probe+0x158/0x290
          __driver_probe_device+0xc8/0xe0
          driver_probe_device+0x44/0x100
          __driver_attach+0xf8/0x108
          bus_for_each_dev+0x78/0xc4
          driver_attach+0x2c/0x38
          bus_add_driver+0xd0/0x1d8
          driver_register+0xbc/0xf8
          __platform_driver_register+0x30/0x3c
          qnoc_driver_init+0x24/0x30
          do_one_initcall+0x104/0x2bc
          kernel_init_freeable+0x344/0x34c
          kernel_init+0x30/0x134
          ret_from_fork+0x10/0x20

   -> #1 (icc_lock){+.+.}-{3:3}:
          __mutex_lock+0xcc/0x3c8
          mutex_lock_nested+0x30/0x44
          icc_set_bw+0x88/0x2b4
          _set_opp_bw+0x8c/0xd8
          _set_opp+0x19c/0x300
          dev_pm_opp_set_opp+0x84/0x94
          a6xx_gmu_resume+0x18c/0x804
          a6xx_pm_resume+0xf8/0x234
          adreno_runtime_resume+0x2c/0x38
          pm_generic_runtime_resume+0x30/0x44
          __rpm_callback+0x15c/0x174
          rpm_callback+0x78/0x7c
          rpm_resume+0x318/0x524
          __pm_runtime_resume+0x78/0xbc
          adreno_load_gpu+0xc4/0x17c
          msm_open+0x50/0x120
          drm_file_alloc+0x17c/0x228
          drm_open_helper+0x74/0x118
          drm_open+0xa0/0x144
          drm_stub_open+0xd4/0xe4
          chrdev_open+0x1b8/0x1e4
          do_dentry_open+0x2f8/0x38c
          vfs_open+0x34/0x40
          path_openat+0x64c/0x7b4
          do_filp_open+0x54/0xc4
          do_sys_openat2+0x9c/0x100
          do_sys_open+0x50/0x7c
          __arm64_sys_openat+0x28/0x34
          invoke_syscall+0x8c/0x128
          el0_svc_common.constprop.0+0xa0/0x11c
          do_el0_svc+0xac/0xbc
          el0_svc+0x48/0xa0
          el0t_64_sync_handler+0xac/0x13c
          el0t_64_sync+0x190/0x194

   -> #0 (&gmu->lock){+.+.}-{3:3}:
          __lock_acquire+0xe00/0x1060
          lock_acquire+0x1e0/0x2f8
          __mutex_lock+0xcc/0x3c8
          mutex_lock_nested+0x30/0x44
          a6xx_pm_resume+0xf0/0x234
          adreno_runtime_resume+0x2c/0x38
          pm_generic_runtime_resume+0x30/0x44
          __rpm_callback+0x15c/0x174
          rpm_callback+0x78/0x7c
          rpm_resume+0x318/0x524
          __pm_runtime_resume+0x78/0xbc
          pm_runtime_get_sync.isra.0+0x14/0x20
          msm_gpu_submit+0x58/0x178
          msm_job_run+0x78/0x150
          drm_sched_main+0x290/0x370
          kthread+0xf0/0x100
          ret_from_fork+0x10/0x20

   other info that might help us debug this:

   Chain exists of:
     &gmu->lock --> mmu_notifier_invalidate_range_start --> dma_fence_map

    Possible unsafe locking scenario:

          CPU0                    CPU1
          ----                    ----
     lock(dma_fence_map);
                                  lock(mmu_notifier_invalidate_range_start);
                                  lock(dma_fence_map);
     lock(&gmu->lock);

    *** DEADLOCK ***

   2 locks held by ring0/132:
    #0: ffffff8087191170 (&gpu->lock){+.+.}-{3:3}, at: msm_job_run+0x64/0x150
    #1: ffffffdb5aee57e8 (dma_fence_map){++++}-{0:0}, at: msm_job_run+0x68/0x150

   stack backtrace:
   CPU: 7 PID: 132 Comm: ring0 Not tainted 6.2.0-rc8-debug+ #554
   Hardware name: Google Lazor (rev1 - 2) with LTE (DT)
   Call trace:
    dump_backtrace.part.0+0xb4/0xf8
    show_stack+0x20/0x38
    dump_stack_lvl+0x9c/0xd0
    dump_stack+0x18/0x34
    print_circular_bug+0x1b4/0x1f0
    check_noncircular+0x78/0xac
    __lock_acquire+0xe00/0x1060
    lock_acquire+0x1e0/0x2f8
    __mutex_lock+0xcc/0x3c8
    mutex_lock_nested+0x30/0x44
    a6xx_pm_resume+0xf0/0x234
    adreno_runtime_resume+0x2c/0x38
    pm_generic_runtime_resume+0x30/0x44
    __rpm_callback+0x15c/0x174
    rpm_callback+0x78/0x7c
    rpm_resume+0x318/0x524
    __pm_runtime_resume+0x78/0xbc
    pm_runtime_get_sync.isra.0+0x14/0x20
    msm_gpu_submit+0x58/0x178
    msm_job_run+0x78/0x150
    drm_sched_main+0x290/0x370
    kthread+0xf0/0x100
    ret_from_fork+0x10/0x20

Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20230807171148.210181-7-robdclark@gmail.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 24, 2023
[ Upstream commit 7deac11 ]

Except for initial reference, mddev->kobject is referenced by
rdev->kobject, and if the last rdev is freed, there is no guarantee that
mddev is still valid. Hence mddev should not be used anymore after
export_rdev().

This problem can be triggered by following test for mdadm at very
low rate:

New file: mdadm/tests/23rdev-lifetime

devname=${dev0##*/}
devt=`cat /sys/block/$devname/dev`
pid=""
runtime=2

clean_up_test() {
        pill -9 $pid
        echo clear > /sys/block/md0/md/array_state
}

trap 'clean_up_test' EXIT

add_by_sysfs() {
        while true; do
                echo $devt > /sys/block/md0/md/new_dev
        done
}

remove_by_sysfs(){
        while true; do
                echo remove > /sys/block/md0/md/dev-${devname}/state
        done
}

echo md0 > /sys/module/md_mod/parameters/new_array || die "create md0 failed"

add_by_sysfs &
pid="$pid $!"

remove_by_sysfs &
pid="$pid $!"

sleep $runtime
exit 0

Test cmd:

./test --save-logs --logdir=/tmp/ --keep-going --dev=loop --tests=23rdev-lifetime

Test result:

general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bcb: 0000 [#4] PREEMPT SMP
CPU: 0 PID: 1292 Comm: test Tainted: G      D W          6.5.0-rc2-00121-g01e55c376936 #562
RIP: 0010:md_wakeup_thread+0x9e/0x320 [md_mod]
Call Trace:
 <TASK>
 mddev_unlock+0x1b6/0x310 [md_mod]
 rdev_attr_store+0xec/0x190 [md_mod]
 sysfs_kf_write+0x52/0x70
 kernfs_fop_write_iter+0x19a/0x2a0
 vfs_write+0x3b5/0x770
 ksys_write+0x74/0x150
 __x64_sys_write+0x22/0x30
 do_syscall_64+0x40/0x90
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fix this problem by don't dereference mddev after export_rdev().

Fixes: 3ce94ce ("md: fix duplicate filename for rdev")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825025532.1523008-2-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Sep 27, 2023
Fix an error detected by memory sanitizer:
```
==4033==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x55fb0fbedfc7 in read_alias_info tools/perf/util/pmu.c:457:6
    #1 0x55fb0fbea339 in check_info_data tools/perf/util/pmu.c:1434:2
    #2 0x55fb0fbea339 in perf_pmu__check_alias tools/perf/util/pmu.c:1504:9
    #3 0x55fb0fbdca85 in parse_events_add_pmu tools/perf/util/parse-events.c:1429:32
    #4 0x55fb0f965230 in parse_events_parse tools/perf/util/parse-events.y:299:6
    #5 0x55fb0fbdf6b2 in parse_events__scanner tools/perf/util/parse-events.c:1822:8
    #6 0x55fb0fbdf8c1 in __parse_events tools/perf/util/parse-events.c:2094:8
    #7 0x55fb0fa8ffa9 in parse_events tools/perf/util/parse-events.h:41:9
    #8 0x55fb0fa8ffa9 in test_event tools/perf/tests/parse-events.c:2393:8
    #9 0x55fb0fa8f458 in test__pmu_events tools/perf/tests/parse-events.c:2551:15
    #10 0x55fb0fa6d93f in run_test tools/perf/tests/builtin-test.c:242:9
    #11 0x55fb0fa6d93f in test_and_print tools/perf/tests/builtin-test.c:271:8
    #12 0x55fb0fa6d082 in __cmd_test tools/perf/tests/builtin-test.c:442:5
    #13 0x55fb0fa6d082 in cmd_test tools/perf/tests/builtin-test.c:564:9
    #14 0x55fb0f942720 in run_builtin tools/perf/perf.c:322:11
    #15 0x55fb0f942486 in handle_internal_command tools/perf/perf.c:375:8
    #16 0x55fb0f941dab in run_argv tools/perf/perf.c:419:2
    #17 0x55fb0f941dab in main tools/perf/perf.c:535:3
```

Fixes: 7b723db ("perf pmu: Be lazy about loading event info files from sysfs")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20230914022425.1489035-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
donald pushed a commit that referenced this issue Oct 4, 2023
The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
donald pushed a commit that referenced this issue Oct 8, 2023
Fix the deadlock by refactoring the MR cache cleanup flow to flush the
workqueue without holding the rb_lock.
This adds a race between cache cleanup and creation of new entries which
we solve by denied creation of new entries after cache cleanup started.

Lockdep:
WARNING: possible circular locking dependency detected
 [ 2785.326074 ] 6.2.0-rc6_for_upstream_debug_2023_01_31_14_02 #1 Not tainted
 [ 2785.339778 ] ------------------------------------------------------
 [ 2785.340848 ] devlink/53872 is trying to acquire lock:
 [ 2785.341701 ] ffff888124f8c0c8 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0xc8/0x900
 [ 2785.343403 ]
 [ 2785.343403 ] but task is already holding lock:
 [ 2785.344464 ] ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib]
 [ 2785.346273 ]
 [ 2785.346273 ] which lock already depends on the new lock.
 [ 2785.346273 ]
 [ 2785.347720 ]
 [ 2785.347720 ] the existing dependency chain (in reverse order) is:
 [ 2785.349003 ]
 [ 2785.349003 ] -> #1 (&dev->cache.rb_lock){+.+.}-{3:3}:
 [ 2785.350160 ]        __mutex_lock+0x14c/0x15c0
 [ 2785.350962 ]        delayed_cache_work_func+0x2d1/0x610 [mlx5_ib]
 [ 2785.352044 ]        process_one_work+0x7c2/0x1310
 [ 2785.352879 ]        worker_thread+0x59d/0xec0
 [ 2785.353636 ]        kthread+0x28f/0x330
 [ 2785.354370 ]        ret_from_fork+0x1f/0x30
 [ 2785.355135 ]
 [ 2785.355135 ] -> #0 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}:
 [ 2785.356515 ]        __lock_acquire+0x2d8a/0x5fe0
 [ 2785.357349 ]        lock_acquire+0x1c1/0x540
 [ 2785.358121 ]        __flush_work+0xe8/0x900
 [ 2785.358852 ]        __cancel_work_timer+0x2c7/0x3f0
 [ 2785.359711 ]        mlx5_mkey_cache_cleanup+0xfb/0x250 [mlx5_ib]
 [ 2785.360781 ]        mlx5_ib_stage_pre_ib_reg_umr_cleanup+0x16/0x30 [mlx5_ib]
 [ 2785.361969 ]        __mlx5_ib_remove+0x68/0x120 [mlx5_ib]
 [ 2785.362960 ]        mlx5r_remove+0x63/0x80 [mlx5_ib]
 [ 2785.363870 ]        auxiliary_bus_remove+0x52/0x70
 [ 2785.364715 ]        device_release_driver_internal+0x3c1/0x600
 [ 2785.365695 ]        bus_remove_device+0x2a5/0x560
 [ 2785.366525 ]        device_del+0x492/0xb80
 [ 2785.367276 ]        mlx5_detach_device+0x1a9/0x360 [mlx5_core]
 [ 2785.368615 ]        mlx5_unload_one_devl_locked+0x5a/0x110 [mlx5_core]
 [ 2785.369934 ]        mlx5_devlink_reload_down+0x292/0x580 [mlx5_core]
 [ 2785.371292 ]        devlink_reload+0x439/0x590
 [ 2785.372075 ]        devlink_nl_cmd_reload+0xaef/0xff0
 [ 2785.372973 ]        genl_family_rcv_msg_doit.isra.0+0x1bd/0x290
 [ 2785.374011 ]        genl_rcv_msg+0x3ca/0x6c0
 [ 2785.374798 ]        netlink_rcv_skb+0x12c/0x360
 [ 2785.375612 ]        genl_rcv+0x24/0x40
 [ 2785.376295 ]        netlink_unicast+0x438/0x710
 [ 2785.377121 ]        netlink_sendmsg+0x7a1/0xca0
 [ 2785.377926 ]        sock_sendmsg+0xc5/0x190
 [ 2785.378668 ]        __sys_sendto+0x1bc/0x290
 [ 2785.379440 ]        __x64_sys_sendto+0xdc/0x1b0
 [ 2785.380255 ]        do_syscall_64+0x3d/0x90
 [ 2785.381031 ]        entry_SYSCALL_64_after_hwframe+0x46/0xb0
 [ 2785.381967 ]
 [ 2785.381967 ] other info that might help us debug this:
 [ 2785.381967 ]
 [ 2785.383448 ]  Possible unsafe locking scenario:
 [ 2785.383448 ]
 [ 2785.384544 ]        CPU0                    CPU1
 [ 2785.385383 ]        ----                    ----
 [ 2785.386193 ]   lock(&dev->cache.rb_lock);
 [ 2785.386940 ]				lock((work_completion)(&(&ent->dwork)->work));
 [ 2785.388327 ]				lock(&dev->cache.rb_lock);
 [ 2785.389425 ]   lock((work_completion)(&(&ent->dwork)->work));
 [ 2785.390414 ]
 [ 2785.390414 ]  *** DEADLOCK ***
 [ 2785.390414 ]
 [ 2785.391579 ] 6 locks held by devlink/53872:
 [ 2785.392341 ]  #0: ffffffff84c17a50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40
 [ 2785.393630 ]  #1: ffff888142280218 (&devlink->lock_key){+.+.}-{3:3}, at: devlink_get_from_attrs_lock+0x12d/0x2d0
 [ 2785.395324 ]  #2: ffff8881422d3c38 (&dev->lock_key){+.+.}-{3:3}, at: mlx5_unload_one_devl_locked+0x4a/0x110 [mlx5_core]
 [ 2785.397322 ]  #3: ffffffffa0e59068 (mlx5_intf_mutex){+.+.}-{3:3}, at: mlx5_detach_device+0x60/0x360 [mlx5_core]
 [ 2785.399231 ]  #4: ffff88810e3cb0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x8d/0x600
 [ 2785.400864 ]  #5: ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib]

Fixes: b958451 ("RDMA/mlx5: Change the cache structure to an RB-tree")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Signed-off-by: Michael Guralnik <michaelgur@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
donald pushed a commit that referenced this issue Oct 11, 2023
[ Upstream commit a154f5f ]

The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Oct 11, 2023
[ Upstream commit a154f5f ]

The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue May 23, 2025
commit 78ab4be upstream.

A warning on driver removal started occurring after commit 9dd05df
("net: warn if NAPI instance wasn't shut down"). Disable tx napi before
deleting it in mt76_dma_cleanup().

 WARNING: CPU: 4 PID: 18828 at net/core/dev.c:7288 __netif_napi_del_locked+0xf0/0x100
 CPU: 4 UID: 0 PID: 18828 Comm: modprobe Not tainted 6.15.0-rc4 #4 PREEMPT(lazy)
 Hardware name: ASUS System Product Name/PRIME X670E-PRO WIFI, BIOS 3035 09/05/2024
 RIP: 0010:__netif_napi_del_locked+0xf0/0x100
 Call Trace:
 <TASK>
 mt76_dma_cleanup+0x54/0x2f0 [mt76]
 mt7921_pci_remove+0xd5/0x190 [mt7921e]
 pci_device_remove+0x47/0xc0
 device_release_driver_internal+0x19e/0x200
 driver_detach+0x48/0x90
 bus_remove_driver+0x6d/0xf0
 pci_unregister_driver+0x2e/0xb0
 __do_sys_delete_module.isra.0+0x197/0x2e0
 do_syscall_64+0x7b/0x160
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Tested with mt7921e but the same pattern can be actually applied to other
mt76 drivers calling mt76_dma_cleanup() during removal. Tx napi is enabled
in their *_dma_init() functions and only toggled off and on again inside
their suspend/resume/reset paths. So it should be okay to disable tx
napi in such a generic way.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 2ac515a ("mt76: mt76x02: use napi polling for tx cleanup")
Cc: stable@vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Tested-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com>
Link: https://patch.msgid.link/20250506115540.19045-1-pchelkin@ispras.ru
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
donald pushed a commit that referenced this issue May 27, 2025
…xit()

scheduler's ->exit() is called with queue frozen and elevator lock is held, and
wbt_enable_default() can't be called with queue frozen, otherwise the
following lockdep warning is triggered:

	#6 (&q->rq_qos_mutex){+.+.}-{4:4}:
	#5 (&eq->sysfs_lock){+.+.}-{4:4}:
	#4 (&q->elevator_lock){+.+.}-{4:4}:
	#3 (&q->q_usage_counter(io)#3){++++}-{0:0}:
	#2 (fs_reclaim){+.+.}-{0:0}:
	#1 (&sb->s_type->i_mutex_key#3){+.+.}-{4:4}:
	#0 (&q->debugfs_mutex){+.+.}-{4:4}:

Fix the issue by moving wbt_enable_default() out of bfq's exit(), and
call it from elevator_change_done().

Meantime add disk->rqos_state_mutex for covering wbt state change, which
matches the purpose more than ->elevator_lock.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-26-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
donald pushed a commit that referenced this issue May 28, 2025
ACPICA commit 1c28da2242783579d59767617121035dafba18c3

This was originally done in NetBSD:
https://github.com/NetBSD/src/commit/b69d1ac3f7702f67edfe412e4392f77d09804910
and is the correct alternative to the smattering of `memcpy`s I
previously contributed to this repository.

This also sidesteps the newly strict checks added in UBSAN:
https://github.com/llvm/llvm-project/commit/792674400f6f04a074a3827349ed0e2ac10067f6

Before this change we see the following UBSAN stack trace in Fuchsia:

  #0    0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e
  #1.2  0x000021982bc4af3c in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x41f3c
  #1.1  0x000021982bc4af3c in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x41f3c
  #1    0x000021982bc4af3c in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:395 <libclang_rt.asan.so>+0x41f3c
  #2    0x000021982bc4bb6f in handletype_mismatch_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:137 <libclang_rt.asan.so>+0x42b6f
  #3    0x000021982bc4b723 in __ubsan_handle_type_mismatch_v1 compiler-rt/lib/ubsan/ubsan_handlers.cpp:142 <libclang_rt.asan.so>+0x42723
  #4    0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e
  #5    0x000021afcfdf2089 in acpi_rs_convert_aml_to_resource(struct acpi_resource*, union aml_resource*, struct acpi_rsconvert_info*) ../../third_party/acpica/source/components/resources/rsmisc.c:355 <platform-bus-x86.so>+0x6b2089
  #6    0x000021afcfded169 in acpi_rs_convert_aml_to_resources(u8*, u32, u32, u8, void**) ../../third_party/acpica/source/components/resources/rslist.c:137 <platform-bus-x86.so>+0x6ad169
  #7    0x000021afcfe2d24a in acpi_ut_walk_aml_resources(struct acpi_walk_state*, u8*, acpi_size, acpi_walk_aml_callback, void**) ../../third_party/acpica/source/components/utilities/utresrc.c:237 <platform-bus-x86.so>+0x6ed24a
  #8    0x000021afcfde66b7 in acpi_rs_create_resource_list(union acpi_operand_object*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rscreate.c:199 <platform-bus-x86.so>+0x6a66b7
  #9    0x000021afcfdf6979 in acpi_rs_get_method_data(acpi_handle, const char*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rsutils.c:770 <platform-bus-x86.so>+0x6b6979
  #10   0x000021afcfdf708f in acpi_walk_resources(acpi_handle, char*, acpi_walk_resource_callback, void*) ../../third_party/acpica/source/components/resources/rsxface.c:731 <platform-bus-x86.so>+0x6b708f
  #11   0x000021afcfa95dcf in acpi::acpi_impl::walk_resources(acpi::acpi_impl*, acpi_handle, const char*, acpi::Acpi::resources_callable) ../../src/devices/board/lib/acpi/acpi-impl.cc:41 <platform-bus-x86.so>+0x355dcf
  #12   0x000021afcfaa8278 in acpi::device_builder::gather_resources(acpi::device_builder*, acpi::Acpi*, fidl::any_arena&, acpi::Manager*, acpi::device_builder::gather_resources_callback) ../../src/devices/board/lib/acpi/device-builder.cc:84 <platform-bus-x86.so>+0x368278
  #13   0x000021afcfbddb87 in acpi::Manager::configure_discovered_devices(acpi::Manager*) ../../src/devices/board/lib/acpi/manager.cc:75 <platform-bus-x86.so>+0x49db87
  #14   0x000021afcf99091d in publish_acpi_devices(acpi::Manager*, zx_device_t*, zx_device_t*) ../../src/devices/board/drivers/x86/acpi-nswalk.cc:95 <platform-bus-x86.so>+0x25091d
  #15   0x000021afcf9c1d4e in x86::X86::do_init(x86::X86*) ../../src/devices/board/drivers/x86/x86.cc:60 <platform-bus-x86.so>+0x281d4e
  #16   0x000021afcf9e33ad in λ(x86::X86::ddk_init::(anon class)*) ../../src/devices/board/drivers/x86/x86.cc:77 <platform-bus-x86.so>+0x2a33ad
  #17   0x000021afcf9e313e in fit::internal::target<(lambda at../../src/devices/board/drivers/x86/x86.cc:76:19), false, false, std::__2::allocator<std::byte>, void>::invoke(void*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:183 <platform-bus-x86.so>+0x2a313e
  #18   0x000021afcfbab4c7 in fit::internal::function_base<16UL, false, void(), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <platform-bus-x86.so>+0x46b4c7
  #19   0x000021afcfbab342 in fit::function_impl<16UL, false, void(), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/function.h:315 <platform-bus-x86.so>+0x46b342
  #20   0x000021afcfcd98c3 in async::internal::retained_task::Handler(async_dispatcher_t*, async_task_t*, zx_status_t) ../../sdk/lib/async/task.cc:24 <platform-bus-x86.so>+0x5998c3
  #21   0x00002290f9924616 in λ(const driver_runtime::Dispatcher::post_task::(anon class)*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/dispatcher.cc:789 <libdriver_runtime.so>+0x10a616
  #22   0x00002290f9924323 in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:788:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int>::invoke(void*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0x10a323
  #23   0x00002290f9904b76 in fit::internal::function_base<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xeab76
  #24   0x00002290f9904831 in fit::callback_impl<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::operator()(fit::callback_impl<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/function.h:471 <libdriver_runtime.so>+0xea831
  #25   0x00002290f98d5adc in driver_runtime::callback_request::Call(driver_runtime::callback_request*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/callback_request.h:74 <libdriver_runtime.so>+0xbbadc
  #26   0x00002290f98e1e58 in driver_runtime::Dispatcher::dispatch_callback(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >) ../../src/devices/bin/driver_runtime/dispatcher.cc:1248 <libdriver_runtime.so>+0xc7e58
  #27   0x00002290f98e4159 in driver_runtime::Dispatcher::dispatch_callbacks(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:1308 <libdriver_runtime.so>+0xca159
  #28   0x00002290f9918414 in λ(const driver_runtime::Dispatcher::create_with_adder::(anon class)*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:353 <libdriver_runtime.so>+0xfe414
  #29   0x00002290f991812d in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:351:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>>::invoke(void*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0xfe12d
  #30   0x00002290f9906fc7 in fit::internal::function_base<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xecfc7
  #31   0x00002290f9906c66 in fit::function_impl<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/function.h:315 <libdriver_runtime.so>+0xecc66
  #32   0x00002290f98e73d9 in driver_runtime::Dispatcher::event_waiter::invoke_callback(driver_runtime::Dispatcher::event_waiter*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.h:543 <libdriver_runtime.so>+0xcd3d9
  #33   0x00002290f98e700d in driver_runtime::Dispatcher::event_waiter::handle_event(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/dispatcher.cc:1442 <libdriver_runtime.so>+0xcd00d
  #34   0x00002290f9918983 in async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event(async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>*, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/async_loop_owned_event_handler.h:59 <libdriver_runtime.so>+0xfe983
  #35   0x00002290f9918b9e in async::wait_method<async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>, &async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event>::call_handler(async_dispatcher_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async/include/lib/async/cpp/wait.h:201 <libdriver_runtime.so>+0xfeb9e
  #36   0x00002290f99bf509 in async_loop_dispatch_wait(async_loop_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async-loop/loop.c:394 <libdriver_runtime.so>+0x1a5509
  #37   0x00002290f99b9958 in async_loop_run_once(async_loop_t*, zx_time_t) ../../sdk/lib/async-loop/loop.c:343 <libdriver_runtime.so>+0x19f958
  #38   0x00002290f99b9247 in async_loop_run(async_loop_t*, zx_time_t, _Bool) ../../sdk/lib/async-loop/loop.c:301 <libdriver_runtime.so>+0x19f247
  #39   0x00002290f99ba962 in async_loop_run_thread(void*) ../../sdk/lib/async-loop/loop.c:860 <libdriver_runtime.so>+0x1a0962
  #40   0x000041afd176ef30 in start_c11(void*) ../../zircon/third_party/ulib/musl/pthread/pthread_create.c:63 <libc.so>+0x84f30
  #41   0x000041afd18a448d in thread_trampoline(uintptr_t, uintptr_t) ../../zircon/system/ulib/runtime/thread.cc:100 <libc.so>+0x1ba48d

Link: https://github.com/acpica/acpica/commit/1c28da22
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/4664267.LvFx2qVVIh@rjwysocki.net
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
[ rjw: Pick up the tag from Tamir ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
donald pushed a commit that referenced this issue May 30, 2025
Intel TDX protects guest VM's from malicious host and certain physical
attacks.  TDX introduces a new operation mode, Secure Arbitration Mode
(SEAM) to isolate and protect guest VM's.  A TDX guest VM runs in SEAM and,
unlike VMX, direct control and interaction with the guest by the host VMM
is not possible.  Instead, Intel TDX Module, which also runs in SEAM,
provides a SEAMCALL API.

The SEAMCALL that provides the ability to enter a guest is TDH.VP.ENTER.
The TDX Module processes TDH.VP.ENTER, and enters the guest via VMX
VMLAUNCH/VMRESUME instructions.  When a guest VM-exit requires host VMM
interaction, the TDH.VP.ENTER SEAMCALL returns to the host VMM (KVM).

Add tdh_vp_enter() to wrap the SEAMCALL invocation of TDH.VP.ENTER;
tdh_vp_enter() needs to be noinstr because VM entry in KVM is noinstr
as well, which is for two reasons:
* marking the area as CT_STATE_GUEST via guest_state_enter_irqoff() and
  guest_state_exit_irqoff()
* IRET must be avoided between VM-exit and NMI handling, in order to
  avoid prematurely releasing the NMI inhibit.

TDH.VP.ENTER is different from other SEAMCALLs in several ways: it
uses more arguments, and after it returns some host state may need to be
restored.  Therefore tdh_vp_enter() uses __seamcall_saved_ret() instead of
__seamcall_ret(); since it is the only caller of __seamcall_saved_ret(),
it can be made noinstr also.

TDH.VP.ENTER arguments are passed through General Purpose Registers (GPRs).
For the special case of the TD guest invoking TDG.VP.VMCALL, nearly any GPR
can be used, as well as XMM0 to XMM15. Notably, RBP is not used, and Linux
mandates the TDX Module feature NO_RBP_MOD, which is enforced elsewhere.
Additionally, XMM registers are not required for the existing Guest
Hypervisor Communication Interface and are handled by existing KVM code
should they be modified by the guest.

There are 2 input formats and 5 output formats for TDH.VP.ENTER arguments.
Input #1 : Initial entry or following a previous async. TD Exit
Input #2 : Following a previous TDCALL(TDG.VP.VMCALL)
Output #1 : On Error (No TD Entry)
Output #2 : Async. Exits with a VMX Architectural Exit Reason
Output #3 : Async. Exits with a non-VMX TD Exit Status
Output #4 : Async. Exits with Cross-TD Exit Details
Output #5 : On TDCALL(TDG.VP.VMCALL)

Currently, to keep things simple, the wrapper function does not attempt
to support different formats, and just passes all the GPRs that could be
used.  The GPR values are held by KVM in the area set aside for guest
GPRs.  KVM code uses the guest GPR area (vcpu->arch.regs[]) to set up for
or process results of tdh_vp_enter().

Therefore changing tdh_vp_enter() to use more complex argument formats
would also alter the way KVM code interacts with tdh_vp_enter().

Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Message-ID: <20241121201448.36170-2-adrian.hunter@intel.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
donald pushed a commit that referenced this issue May 30, 2025
[ Upstream commit 88f7f56 ]

When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush()
generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
which causes the flush_bio to be throttled by wbt_wait().

An example from v5.4, similar problem also exists in upstream:

    crash> bt 2091206
    PID: 2091206  TASK: ffff2050df92a300  CPU: 109  COMMAND: "kworker/u260:0"
     #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8
     #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4
     #2 [ffff800084a2f880] schedule at ffff800040bfa4b4
     #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4
     #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc
     #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0
     #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254
     #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38
     #8 [ffff800084a2fa60] generic_make_request at ffff800040570138
     #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4
    #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs]
    #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs]
    #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs]
    #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs]
    #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs]
    #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs]
    #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08
    #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc
    #18 [ffff800084a2fe70] kthread at ffff800040118de4

After commit 2def284 ("xfs: don't allow log IO to be throttled"),
the metadata submitted by xlog_write_iclog() should not be throttled.
But due to the existence of the dm layer, throttling flush_bio indirectly
causes the metadata bio to be throttled.

Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes
wbt_should_throttle() return false to avoid wbt_wait().

Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Reviewed-by: Tianxiang Peng <txpeng@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue May 30, 2025
[ Upstream commit 88f7f56 ]

When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush()
generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
which causes the flush_bio to be throttled by wbt_wait().

An example from v5.4, similar problem also exists in upstream:

    crash> bt 2091206
    PID: 2091206  TASK: ffff2050df92a300  CPU: 109  COMMAND: "kworker/u260:0"
     #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8
     #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4
     #2 [ffff800084a2f880] schedule at ffff800040bfa4b4
     #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4
     #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc
     #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0
     #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254
     #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38
     #8 [ffff800084a2fa60] generic_make_request at ffff800040570138
     #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4
    #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs]
    #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs]
    #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs]
    #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs]
    #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs]
    #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs]
    #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08
    #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc
    #18 [ffff800084a2fe70] kthread at ffff800040118de4

After commit 2def284 ("xfs: don't allow log IO to be throttled"),
the metadata submitted by xlog_write_iclog() should not be throttled.
But due to the existence of the dm layer, throttling flush_bio indirectly
causes the metadata bio to be throttled.

Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes
wbt_should_throttle() return false to avoid wbt_wait().

Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Reviewed-by: Tianxiang Peng <txpeng@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 1, 2025
Running a modified trace-cmd record --nosplice where it does a mmap of the
ring buffer when '--nosplice' is set, caused the following lockdep splat:

 ======================================================
 WARNING: possible circular locking dependency detected
 6.15.0-rc7-test-00002-gfb7d03d8a82f #551 Not tainted
 ------------------------------------------------------
 trace-cmd/1113 is trying to acquire lock:
 ffff888100062888 (&buffer->mutex){+.+.}-{4:4}, at: ring_buffer_map+0x11c/0xe70

 but task is already holding lock:
 ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #5 (&cpu_buffer->mapping_lock){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        ring_buffer_map+0xcf/0xe70
        tracing_buffers_mmap+0x1c4/0x3b0
        __mmap_region+0xd8d/0x1f70
        do_mmap+0x9d7/0x1010
        vm_mmap_pgoff+0x20b/0x390
        ksys_mmap_pgoff+0x2e9/0x440
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #4 (&mm->mmap_lock){++++}-{4:4}:
        __might_fault+0xa5/0x110
        _copy_to_user+0x22/0x80
        _perf_ioctl+0x61b/0x1b70
        perf_ioctl+0x62/0x90
        __x64_sys_ioctl+0x134/0x190
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #3 (&cpuctx_mutex){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        perf_event_init_cpu+0x325/0x7c0
        perf_event_init+0x52a/0x5b0
        start_kernel+0x263/0x3e0
        x86_64_start_reservations+0x24/0x30
        x86_64_start_kernel+0x95/0xa0
        common_startup_64+0x13e/0x141

 -> #2 (pmus_lock){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        perf_event_init_cpu+0xb7/0x7c0
        cpuhp_invoke_callback+0x2c0/0x1030
        __cpuhp_invoke_callback_range+0xbf/0x1f0
        _cpu_up+0x2e7/0x690
        cpu_up+0x117/0x170
        cpuhp_bringup_mask+0xd5/0x120
        bringup_nonboot_cpus+0x13d/0x170
        smp_init+0x2b/0xf0
        kernel_init_freeable+0x441/0x6d0
        kernel_init+0x1e/0x160
        ret_from_fork+0x34/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #1 (cpu_hotplug_lock){++++}-{0:0}:
        cpus_read_lock+0x2a/0xd0
        ring_buffer_resize+0x610/0x14e0
        __tracing_resize_ring_buffer.part.0+0x42/0x120
        tracing_set_tracer+0x7bd/0xa80
        tracing_set_trace_write+0x132/0x1e0
        vfs_write+0x21c/0xe80
        ksys_write+0xf9/0x1c0
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #0 (&buffer->mutex){+.+.}-{4:4}:
        __lock_acquire+0x1405/0x2210
        lock_acquire+0x174/0x310
        __mutex_lock+0x192/0x18c0
        ring_buffer_map+0x11c/0xe70
        tracing_buffers_mmap+0x1c4/0x3b0
        __mmap_region+0xd8d/0x1f70
        do_mmap+0x9d7/0x1010
        vm_mmap_pgoff+0x20b/0x390
        ksys_mmap_pgoff+0x2e9/0x440
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 other info that might help us debug this:

 Chain exists of:
   &buffer->mutex --> &mm->mmap_lock --> &cpu_buffer->mapping_lock

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&cpu_buffer->mapping_lock);
                                lock(&mm->mmap_lock);
                                lock(&cpu_buffer->mapping_lock);
   lock(&buffer->mutex);

  *** DEADLOCK ***

 2 locks held by trace-cmd/1113:
  #0: ffff888106b847e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x192/0x390
  #1: ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70

 stack backtrace:
 CPU: 5 UID: 0 PID: 1113 Comm: trace-cmd Not tainted 6.15.0-rc7-test-00002-gfb7d03d8a82f #551 PREEMPT
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x6e/0xa0
  print_circular_bug.cold+0x178/0x1be
  check_noncircular+0x146/0x160
  __lock_acquire+0x1405/0x2210
  lock_acquire+0x174/0x310
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? __mutex_lock+0x169/0x18c0
  __mutex_lock+0x192/0x18c0
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? function_trace_call+0x296/0x370
  ? __pfx___mutex_lock+0x10/0x10
  ? __pfx_function_trace_call+0x10/0x10
  ? __pfx___mutex_lock+0x10/0x10
  ? _raw_spin_unlock+0x2d/0x50
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? __mutex_lock+0x5/0x18c0
  ring_buffer_map+0x11c/0xe70
  ? do_raw_spin_lock+0x12d/0x270
  ? find_held_lock+0x2b/0x80
  ? _raw_spin_unlock+0x2d/0x50
  ? rcu_is_watching+0x15/0xb0
  ? _raw_spin_unlock+0x2d/0x50
  ? trace_preempt_on+0xd0/0x110
  tracing_buffers_mmap+0x1c4/0x3b0
  __mmap_region+0xd8d/0x1f70
  ? ring_buffer_lock_reserve+0x99/0xff0
  ? __pfx___mmap_region+0x10/0x10
  ? ring_buffer_lock_reserve+0x99/0xff0
  ? __pfx_ring_buffer_lock_reserve+0x10/0x10
  ? __pfx_ring_buffer_lock_reserve+0x10/0x10
  ? bpf_lsm_mmap_addr+0x4/0x10
  ? security_mmap_addr+0x46/0xd0
  ? lock_is_held_type+0xd9/0x130
  do_mmap+0x9d7/0x1010
  ? 0xffffffffc0370095
  ? __pfx_do_mmap+0x10/0x10
  vm_mmap_pgoff+0x20b/0x390
  ? __pfx_vm_mmap_pgoff+0x10/0x10
  ? 0xffffffffc0370095
  ksys_mmap_pgoff+0x2e9/0x440
  do_syscall_64+0x79/0x1c0
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7fb0963a7de2
 Code: 00 00 00 0f 1f 44 00 00 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 3b 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 76 5b 5d c3 0f 1f 00 48 8b 05 e1 9f 0d 00 64
 RSP: 002b:00007ffdcc8fb878 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb0963a7de2
 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 0000000000000000
 RBP: 0000000000000001 R08: 0000000000000006 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007ffdcc8fbe68 R14: 00007fb096628000 R15: 00005633e01a5c90
  </TASK>

The issue is that cpus_read_lock() is taken within buffer->mutex. The
memory mapped pages are taken with the mmap_lock held. The buffer->mutex
is taken within the cpu_buffer->mapping_lock. There's quite a chain with
all these locks, where the deadlock can be fixed by moving the
cpus_read_lock() outside the taking of the buffer->mutex.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250527105820.0f45d045@gandalf.local.home
Fixes: 117c392 ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
donald pushed a commit that referenced this issue Jun 3, 2025
Despite the fact that several lockdep-related checks are skipped when
calling trylock* versions of the locking primitives, for example
mutex_trylock, each time the mutex is acquired, a held_lock is still
placed onto the lockdep stack by __lock_acquire() which is called
regardless of whether the trylock* or regular locking API was used.

This means that if the caller successfully acquires more than
MAX_LOCK_DEPTH locks of the same class, even when using mutex_trylock,
lockdep will still complain that the maximum depth of the held lock stack
has been reached and disable itself.

For example, the following error currently occurs in the ARM version
of KVM, once the code tries to lock all vCPUs of a VM configured with more
than MAX_LOCK_DEPTH vCPUs, a situation that can easily happen on modern
systems, where having more than 48 CPUs is common, and it's also common to
run VMs that have vCPU counts approaching that number:

[  328.171264] BUG: MAX_LOCK_DEPTH too low!
[  328.175227] turning off the locking correctness validator.
[  328.180726] Please attach the output of /proc/lock_stat to the bug report
[  328.187531] depth: 48  max: 48!
[  328.190678] 48 locks held by qemu-kvm/11664:
[  328.194957]  #0: ffff800086de5ba0 (&kvm->lock){+.+.}-{3:3}, at: kvm_ioctl_create_device+0x174/0x5b0
[  328.204048]  #1: ffff0800e78800b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.212521]  #2: ffff07ffeee51e98 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.220991]  #3: ffff0800dc7d80b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.229463]  #4: ffff07ffe0c980b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.237934]  #5: ffff0800a3883c78 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.246405]  #6: ffff07fffbe480b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0

Luckily, in all instances that require locking all vCPUs, the
'kvm->lock' is taken a priori, and that fact makes it possible to use
the little known feature of lockdep, called a 'nest_lock', to avoid this
warning and subsequent lockdep self-disablement.

The action of 'nested lock' being provided to lockdep's lock_acquire(),
causes the lockdep to detect that the top of the held lock stack contains
a lock of the same class and then increment its reference counter instead
of pushing a new held_lock item onto that stack.

See __lock_acquire for more information.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Message-ID: <20250512180407.659015-2-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
donald pushed a commit that referenced this issue Jun 3, 2025
Use kvm_trylock_all_vcpus instead of a custom implementation when locking
all vCPUs of a VM, to avoid triggering a lockdep warning, in the case in
which the VM is configured to have more than MAX_LOCK_DEPTH vCPUs.

This fixes the following false lockdep warning:

[  328.171264] BUG: MAX_LOCK_DEPTH too low!
[  328.175227] turning off the locking correctness validator.
[  328.180726] Please attach the output of /proc/lock_stat to the bug report
[  328.187531] depth: 48  max: 48!
[  328.190678] 48 locks held by qemu-kvm/11664:
[  328.194957]  #0: ffff800086de5ba0 (&kvm->lock){+.+.}-{3:3}, at: kvm_ioctl_create_device+0x174/0x5b0
[  328.204048]  #1: ffff0800e78800b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.212521]  #2: ffff07ffeee51e98 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.220991]  #3: ffff0800dc7d80b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.229463]  #4: ffff07ffe0c980b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.237934]  #5: ffff0800a3883c78 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0
[  328.246405]  #6: ffff07fffbe480b8 (&vcpu->mutex){+.+.}-{3:3}, at: lock_all_vcpus+0x16c/0x2a0

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Message-ID: <20250512180407.659015-6-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
donald pushed a commit that referenced this issue Jun 5, 2025
commit 78ab4be upstream.

A warning on driver removal started occurring after commit 9dd05df
("net: warn if NAPI instance wasn't shut down"). Disable tx napi before
deleting it in mt76_dma_cleanup().

 WARNING: CPU: 4 PID: 18828 at net/core/dev.c:7288 __netif_napi_del_locked+0xf0/0x100
 CPU: 4 UID: 0 PID: 18828 Comm: modprobe Not tainted 6.15.0-rc4 #4 PREEMPT(lazy)
 Hardware name: ASUS System Product Name/PRIME X670E-PRO WIFI, BIOS 3035 09/05/2024
 RIP: 0010:__netif_napi_del_locked+0xf0/0x100
 Call Trace:
 <TASK>
 mt76_dma_cleanup+0x54/0x2f0 [mt76]
 mt7921_pci_remove+0xd5/0x190 [mt7921e]
 pci_device_remove+0x47/0xc0
 device_release_driver_internal+0x19e/0x200
 driver_detach+0x48/0x90
 bus_remove_driver+0x6d/0xf0
 pci_unregister_driver+0x2e/0xb0
 __do_sys_delete_module.isra.0+0x197/0x2e0
 do_syscall_64+0x7b/0x160
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Tested with mt7921e but the same pattern can be actually applied to other
mt76 drivers calling mt76_dma_cleanup() during removal. Tx napi is enabled
in their *_dma_init() functions and only toggled off and on again inside
their suspend/resume/reset paths. So it should be okay to disable tx
napi in such a generic way.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 2ac515a ("mt76: mt76x02: use napi polling for tx cleanup")
Cc: stable@vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Tested-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com>
Link: https://patch.msgid.link/20250506115540.19045-1-pchelkin@ispras.ru
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
donald pushed a commit that referenced this issue Jun 5, 2025
[ Upstream commit 88f7f56 ]

When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush()
generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
which causes the flush_bio to be throttled by wbt_wait().

An example from v5.4, similar problem also exists in upstream:

    crash> bt 2091206
    PID: 2091206  TASK: ffff2050df92a300  CPU: 109  COMMAND: "kworker/u260:0"
     #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8
     #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4
     #2 [ffff800084a2f880] schedule at ffff800040bfa4b4
     #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4
     #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc
     #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0
     #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254
     #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38
     #8 [ffff800084a2fa60] generic_make_request at ffff800040570138
     #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4
    #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs]
    #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs]
    #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs]
    #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs]
    #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs]
    #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs]
    #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08
    #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc
    #18 [ffff800084a2fe70] kthread at ffff800040118de4

After commit 2def284 ("xfs: don't allow log IO to be throttled"),
the metadata submitted by xlog_write_iclog() should not be throttled.
But due to the existence of the dm layer, throttling flush_bio indirectly
causes the metadata bio to be throttled.

Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes
wbt_should_throttle() return false to avoid wbt_wait().

Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Reviewed-by: Tianxiang Peng <txpeng@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 5, 2025
[ Upstream commit 88f7f56 ]

When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush()
generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
which causes the flush_bio to be throttled by wbt_wait().

An example from v5.4, similar problem also exists in upstream:

    crash> bt 2091206
    PID: 2091206  TASK: ffff2050df92a300  CPU: 109  COMMAND: "kworker/u260:0"
     #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8
     #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4
     #2 [ffff800084a2f880] schedule at ffff800040bfa4b4
     #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4
     #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc
     #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0
     #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254
     #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38
     #8 [ffff800084a2fa60] generic_make_request at ffff800040570138
     #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4
    #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs]
    #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs]
    #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs]
    #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs]
    #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs]
    #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs]
    #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08
    #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc
    #18 [ffff800084a2fe70] kthread at ffff800040118de4

After commit 2def284 ("xfs: don't allow log IO to be throttled"),
the metadata submitted by xlog_write_iclog() should not be throttled.
But due to the existence of the dm layer, throttling flush_bio indirectly
causes the metadata bio to be throttled.

Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes
wbt_should_throttle() return false to avoid wbt_wait().

Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Reviewed-by: Tianxiang Peng <txpeng@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 8, 2025
This patch enables support for DYNAMIC_FTRACE_WITH_CALL_OPS on RISC-V.
This allows each ftrace callsite to provide an ftrace_ops to the common
ftrace trampoline, allowing each callsite to invoke distinct tracer
functions without the need to fall back to list processing or to
allocate custom trampolines for each callsite. This significantly speeds
up cases where multiple distinct trace functions are used and callsites
are mostly traced by a single tracer.

The idea and most of the implementation is taken from the ARM64's
implementation of the same feature. The idea is to place a pointer to
the ftrace_ops as a literal at a fixed offset from the function entry
point, which can be recovered by the common ftrace trampoline.

We use -fpatchable-function-entry to reserve 8 bytes above the function
entry by emitting 2 4 byte or 4 2 byte  nops depending on the presence of
CONFIG_RISCV_ISA_C. These 8 bytes are patched at runtime with a pointer
to the associated ftrace_ops for that callsite. Functions are aligned to
8 bytes to make sure that the accesses to this literal are atomic.

This approach allows for directly invoking ftrace_ops::func even for
ftrace_ops which are dynamically-allocated (or part of a module),
without going via ftrace_ops_list_func.

We've benchamrked this with the ftrace_ops sample module on Spacemit K1
Jupiter:

Without this patch:

baseline (Linux rivos 6.14.0-09584-g7d06015d936c #3 SMP Sat Mar 29
+-----------------------+-----------------+----------------------------+
|  Number of tracers    | Total time (ns) | Per-call average time      |
|-----------------------+-----------------+----------------------------|
| Relevant | Irrelevant |    100000 calls | Total (ns) | Overhead (ns) |
|----------+------------+-----------------+------------+---------------|
|        0 |          0 |        1357958 |          13 |             - |
|        0 |          1 |        1302375 |          13 |             - |
|        0 |          2 |        1302375 |          13 |             - |
|        0 |         10 |        1379084 |          13 |             - |
|        0 |        100 |        1302458 |          13 |             - |
|        0 |        200 |        1302333 |          13 |             - |
|----------+------------+-----------------+------------+---------------|
|        1 |          0 |       13677833 |         136 |           123 |
|        1 |          1 |       18500916 |         185 |           172 |
|        1 |          2 |       22856459 |         228 |           215 |
|        1 |         10 |       58824709 |         588 |           575 |
|        1 |        100 |      505141584 |        5051 |          5038 |
|        1 |        200 |     1580473126 |       15804 |         15791 |
|----------+------------+-----------------+------------+---------------|
|        1 |          0 |       13561000 |         135 |           122 |
|        2 |          0 |       19707292 |         197 |           184 |
|       10 |          0 |       67774750 |         677 |           664 |
|      100 |          0 |      714123125 |        7141 |          7128 |
|      200 |          0 |     1918065668 |       19180 |         19167 |
+----------+------------+-----------------+------------+---------------+

Note: per-call overhead is estimated relative to the baseline case with
0 relevant tracers and 0 irrelevant tracers.

With this patch:

v4-rc4 (Linux rivos 6.14.0-09598-gd75747611c93 #4 SMP Sat Mar 29
+-----------------------+-----------------+----------------------------+
|  Number of tracers    | Total time (ns) | Per-call average time      |
|-----------------------+-----------------+----------------------------|
| Relevant | Irrelevant |    100000 calls | Total (ns) | Overhead (ns) |
|----------+------------+-----------------+------------+---------------|
|        0 |          0 |         1459917 |         14 |             - |
|        0 |          1 |         1408000 |         14 |             - |
|        0 |          2 |         1383792 |         13 |             - |
|        0 |         10 |         1430709 |         14 |             - |
|        0 |        100 |         1383791 |         13 |             - |
|        0 |        200 |         1383750 |         13 |             - |
|----------+------------+-----------------+------------+---------------|
|        1 |          0 |         5238041 |         52 |            38 |
|        1 |          1 |         5228542 |         52 |            38 |
|        1 |          2 |         5325917 |         53 |            40 |
|        1 |         10 |         5299667 |         52 |            38 |
|        1 |        100 |         5245250 |         52 |            39 |
|        1 |        200 |         5238459 |         52 |            39 |
|----------+------------+-----------------+------------+---------------|
|        1 |          0 |         5239083 |         52 |            38 |
|        2 |          0 |        19449417 |        194 |           181 |
|       10 |          0 |        67718584 |        677 |           663 |
|      100 |          0 |       709840708 |       7098 |          7085 |
|      200 |          0 |      2203580626 |      22035 |         22022 |
+----------+------------+-----------------+------------+---------------+

Note: per-call overhead is estimated relative to the baseline case with
0 relevant tracers and 0 irrelevant tracers.

As can be seen from the above:

 a) Whenever there is a single relevant tracer function associated with a
    tracee, the overhead of invoking the tracer is constant, and does not
    scale with the number of tracers which are *not* associated with that
    tracee.

 b) The overhead for a single relevant tracer has dropped to ~1/3 of the
    overhead prior to this series (from 122ns to 38ns). This is largely
    due to permitting calls to dynamically-allocated ftrace_ops without
    going through ftrace_ops_list_func.

Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>

[update kconfig, asm, refactor]

Signed-off-by: Andy Chiu <andybnac@gmail.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20250407180838.42877-10-andybnac@gmail.com
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
donald pushed a commit that referenced this issue Jun 20, 2025
Before the commit under the Fixes tag below, bnxt_ulp_stop() and
bnxt_ulp_start() were always invoked in pairs.  After that commit,
the new bnxt_ulp_restart() can be invoked after bnxt_ulp_stop()
has been called.  This may result in the RoCE driver's aux driver
.suspend() method being invoked twice.  The 2nd bnxt_re_suspend()
call will crash when it dereferences a NULL pointer:

(NULL ib_device): Handle device suspend call
BUG: kernel NULL pointer dereference, address: 0000000000000b78
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP PTI
CPU: 20 UID: 0 PID: 181 Comm: kworker/u96:5 Tainted: G S                  6.15.0-rc1 #4 PREEMPT(voluntary)
Tainted: [S]=CPU_OUT_OF_SPEC
Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017
Workqueue: bnxt_pf_wq bnxt_sp_task [bnxt_en]
RIP: 0010:bnxt_re_suspend+0x45/0x1f0 [bnxt_re]
Code: 8b 05 a7 3c 5b f5 48 89 44 24 18 31 c0 49 8b 5c 24 08 4d 8b 2c 24 e8 ea 06 0a f4 48 c7 c6 04 60 52 c0 48 89 df e8 1b ce f9 ff <48> 8b 83 78 0b 00 00 48 8b 80 38 03 00 00 a8 40 0f 85 b5 00 00 00
RSP: 0018:ffffa2e84084fd88 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffffb4b6b934 RDI: 00000000ffffffff
RBP: ffffa1760954c9c0 R08: 0000000000000000 R09: c0000000ffffdfff
R10: 0000000000000001 R11: ffffa2e84084fb50 R12: ffffa176031ef070
R13: ffffa17609775000 R14: ffffa17603adc180 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffffa17daa397000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000b78 CR3: 00000004aaa30003 CR4: 00000000003706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bnxt_ulp_stop+0x69/0x90 [bnxt_en]
bnxt_sp_task+0x678/0x920 [bnxt_en]
? __schedule+0x514/0xf50
process_scheduled_works+0x9d/0x400
worker_thread+0x11c/0x260
? __pfx_worker_thread+0x10/0x10
kthread+0xfe/0x1e0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2b/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30

Check the BNXT_EN_FLAG_ULP_STOPPED flag and do not proceed if the flag
is already set.  This will preserve the original symmetrical
bnxt_ulp_stop() and bnxt_ulp_start().

Also, inside bnxt_ulp_start(), clear the BNXT_EN_FLAG_ULP_STOPPED
flag after taking the mutex to avoid any race condition.  And for
symmetry, only proceed in bnxt_ulp_start() if the
BNXT_EN_FLAG_ULP_STOPPED is set.

Fixes: 3c163f3 ("bnxt_en: Optimize recovery path ULP locking in the driver")
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Co-developed-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250613231841.377988-2-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
donald pushed a commit that referenced this issue Jun 20, 2025
[ Upstream commit ee684de ]

As shown in [1], it is possible to corrupt a BPF ELF file such that
arbitrary BPF instructions are loaded by libbpf. This can be done by
setting a symbol (BPF program) section offset to a large (unsigned)
number such that <section start + symbol offset> overflows and points
before the section data in the memory.

Consider the situation below where:
- prog_start = sec_start + symbol_offset    <-- size_t overflow here
- prog_end   = prog_start + prog_size

    prog_start        sec_start        prog_end        sec_end
        |                |                 |              |
        v                v                 v              v
    .....................|################################|............

The report in [1] also provides a corrupted BPF ELF which can be used as
a reproducer:

    $ readelf -S crash
    Section Headers:
      [Nr] Name              Type             Address           Offset
           Size              EntSize          Flags  Link  Info  Align
    ...
      [ 2] uretprobe.mu[...] PROGBITS         0000000000000000  00000040
           0000000000000068  0000000000000000  AX       0     0     8

    $ readelf -s crash
    Symbol table '.symtab' contains 8 entries:
       Num:    Value          Size Type    Bind   Vis      Ndx Name
    ...
         6: ffffffffffffffb8   104 FUNC    GLOBAL DEFAULT    2 handle_tp

Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will
point before the actual memory where section 2 is allocated.

This is also reported by AddressSanitizer:

    =================================================================
    ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490
    READ of size 104 at 0x7c7302fe0000 thread T0
        #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76)
        #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856
        #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928
        #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930
        #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067
        #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090
        #6 0x000000400c16 in main /poc/poc.c:8
        #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4)
        #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667)
        #9 0x000000400b34 in _start (/poc/poc+0x400b34)

    0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8)
    allocated by thread T0 here:
        #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b)
        #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600)
        #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018)
        #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740

The problem here is that currently, libbpf only checks that the program
end is within the section bounds. There used to be a check
`while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was
removed by commit 6245947 ("libbpf: Allow gaps in BPF program
sections to support overriden weak functions").

Add a check for detecting the overflow of `sec_off + prog_sz` to
bpf_object__init_prog to fix this issue.

[1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md

Fixes: 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions")
Reported-by: lmarch2 <2524158037@qq.com>
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md
Link: https://lore.kernel.org/bpf/20250415155014.397603-1-vmalik@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 20, 2025
commit c98cc97 upstream.

Running a modified trace-cmd record --nosplice where it does a mmap of the
ring buffer when '--nosplice' is set, caused the following lockdep splat:

 ======================================================
 WARNING: possible circular locking dependency detected
 6.15.0-rc7-test-00002-gfb7d03d8a82f #551 Not tainted
 ------------------------------------------------------
 trace-cmd/1113 is trying to acquire lock:
 ffff888100062888 (&buffer->mutex){+.+.}-{4:4}, at: ring_buffer_map+0x11c/0xe70

 but task is already holding lock:
 ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #5 (&cpu_buffer->mapping_lock){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        ring_buffer_map+0xcf/0xe70
        tracing_buffers_mmap+0x1c4/0x3b0
        __mmap_region+0xd8d/0x1f70
        do_mmap+0x9d7/0x1010
        vm_mmap_pgoff+0x20b/0x390
        ksys_mmap_pgoff+0x2e9/0x440
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #4 (&mm->mmap_lock){++++}-{4:4}:
        __might_fault+0xa5/0x110
        _copy_to_user+0x22/0x80
        _perf_ioctl+0x61b/0x1b70
        perf_ioctl+0x62/0x90
        __x64_sys_ioctl+0x134/0x190
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #3 (&cpuctx_mutex){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        perf_event_init_cpu+0x325/0x7c0
        perf_event_init+0x52a/0x5b0
        start_kernel+0x263/0x3e0
        x86_64_start_reservations+0x24/0x30
        x86_64_start_kernel+0x95/0xa0
        common_startup_64+0x13e/0x141

 -> #2 (pmus_lock){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        perf_event_init_cpu+0xb7/0x7c0
        cpuhp_invoke_callback+0x2c0/0x1030
        __cpuhp_invoke_callback_range+0xbf/0x1f0
        _cpu_up+0x2e7/0x690
        cpu_up+0x117/0x170
        cpuhp_bringup_mask+0xd5/0x120
        bringup_nonboot_cpus+0x13d/0x170
        smp_init+0x2b/0xf0
        kernel_init_freeable+0x441/0x6d0
        kernel_init+0x1e/0x160
        ret_from_fork+0x34/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #1 (cpu_hotplug_lock){++++}-{0:0}:
        cpus_read_lock+0x2a/0xd0
        ring_buffer_resize+0x610/0x14e0
        __tracing_resize_ring_buffer.part.0+0x42/0x120
        tracing_set_tracer+0x7bd/0xa80
        tracing_set_trace_write+0x132/0x1e0
        vfs_write+0x21c/0xe80
        ksys_write+0xf9/0x1c0
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #0 (&buffer->mutex){+.+.}-{4:4}:
        __lock_acquire+0x1405/0x2210
        lock_acquire+0x174/0x310
        __mutex_lock+0x192/0x18c0
        ring_buffer_map+0x11c/0xe70
        tracing_buffers_mmap+0x1c4/0x3b0
        __mmap_region+0xd8d/0x1f70
        do_mmap+0x9d7/0x1010
        vm_mmap_pgoff+0x20b/0x390
        ksys_mmap_pgoff+0x2e9/0x440
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 other info that might help us debug this:

 Chain exists of:
   &buffer->mutex --> &mm->mmap_lock --> &cpu_buffer->mapping_lock

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&cpu_buffer->mapping_lock);
                                lock(&mm->mmap_lock);
                                lock(&cpu_buffer->mapping_lock);
   lock(&buffer->mutex);

  *** DEADLOCK ***

 2 locks held by trace-cmd/1113:
  #0: ffff888106b847e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x192/0x390
  #1: ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70

 stack backtrace:
 CPU: 5 UID: 0 PID: 1113 Comm: trace-cmd Not tainted 6.15.0-rc7-test-00002-gfb7d03d8a82f #551 PREEMPT
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x6e/0xa0
  print_circular_bug.cold+0x178/0x1be
  check_noncircular+0x146/0x160
  __lock_acquire+0x1405/0x2210
  lock_acquire+0x174/0x310
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? __mutex_lock+0x169/0x18c0
  __mutex_lock+0x192/0x18c0
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? function_trace_call+0x296/0x370
  ? __pfx___mutex_lock+0x10/0x10
  ? __pfx_function_trace_call+0x10/0x10
  ? __pfx___mutex_lock+0x10/0x10
  ? _raw_spin_unlock+0x2d/0x50
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? __mutex_lock+0x5/0x18c0
  ring_buffer_map+0x11c/0xe70
  ? do_raw_spin_lock+0x12d/0x270
  ? find_held_lock+0x2b/0x80
  ? _raw_spin_unlock+0x2d/0x50
  ? rcu_is_watching+0x15/0xb0
  ? _raw_spin_unlock+0x2d/0x50
  ? trace_preempt_on+0xd0/0x110
  tracing_buffers_mmap+0x1c4/0x3b0
  __mmap_region+0xd8d/0x1f70
  ? ring_buffer_lock_reserve+0x99/0xff0
  ? __pfx___mmap_region+0x10/0x10
  ? ring_buffer_lock_reserve+0x99/0xff0
  ? __pfx_ring_buffer_lock_reserve+0x10/0x10
  ? __pfx_ring_buffer_lock_reserve+0x10/0x10
  ? bpf_lsm_mmap_addr+0x4/0x10
  ? security_mmap_addr+0x46/0xd0
  ? lock_is_held_type+0xd9/0x130
  do_mmap+0x9d7/0x1010
  ? 0xffffffffc0370095
  ? __pfx_do_mmap+0x10/0x10
  vm_mmap_pgoff+0x20b/0x390
  ? __pfx_vm_mmap_pgoff+0x10/0x10
  ? 0xffffffffc0370095
  ksys_mmap_pgoff+0x2e9/0x440
  do_syscall_64+0x79/0x1c0
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7fb0963a7de2
 Code: 00 00 00 0f 1f 44 00 00 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 3b 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 76 5b 5d c3 0f 1f 00 48 8b 05 e1 9f 0d 00 64
 RSP: 002b:00007ffdcc8fb878 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb0963a7de2
 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 0000000000000000
 RBP: 0000000000000001 R08: 0000000000000006 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007ffdcc8fbe68 R14: 00007fb096628000 R15: 00005633e01a5c90
  </TASK>

The issue is that cpus_read_lock() is taken within buffer->mutex. The
memory mapped pages are taken with the mmap_lock held. The buffer->mutex
is taken within the cpu_buffer->mapping_lock. There's quite a chain with
all these locks, where the deadlock can be fixed by moving the
cpus_read_lock() outside the taking of the buffer->mutex.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250527105820.0f45d045@gandalf.local.home
Fixes: 117c392 ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
donald pushed a commit that referenced this issue Jun 20, 2025
[ Upstream commit ee684de ]

As shown in [1], it is possible to corrupt a BPF ELF file such that
arbitrary BPF instructions are loaded by libbpf. This can be done by
setting a symbol (BPF program) section offset to a large (unsigned)
number such that <section start + symbol offset> overflows and points
before the section data in the memory.

Consider the situation below where:
- prog_start = sec_start + symbol_offset    <-- size_t overflow here
- prog_end   = prog_start + prog_size

    prog_start        sec_start        prog_end        sec_end
        |                |                 |              |
        v                v                 v              v
    .....................|################################|............

The report in [1] also provides a corrupted BPF ELF which can be used as
a reproducer:

    $ readelf -S crash
    Section Headers:
      [Nr] Name              Type             Address           Offset
           Size              EntSize          Flags  Link  Info  Align
    ...
      [ 2] uretprobe.mu[...] PROGBITS         0000000000000000  00000040
           0000000000000068  0000000000000000  AX       0     0     8

    $ readelf -s crash
    Symbol table '.symtab' contains 8 entries:
       Num:    Value          Size Type    Bind   Vis      Ndx Name
    ...
         6: ffffffffffffffb8   104 FUNC    GLOBAL DEFAULT    2 handle_tp

Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will
point before the actual memory where section 2 is allocated.

This is also reported by AddressSanitizer:

    =================================================================
    ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490
    READ of size 104 at 0x7c7302fe0000 thread T0
        #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76)
        #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856
        #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928
        #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930
        #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067
        #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090
        #6 0x000000400c16 in main /poc/poc.c:8
        #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4)
        #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667)
        #9 0x000000400b34 in _start (/poc/poc+0x400b34)

    0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8)
    allocated by thread T0 here:
        #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b)
        #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600)
        #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018)
        #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740

The problem here is that currently, libbpf only checks that the program
end is within the section bounds. There used to be a check
`while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was
removed by commit 6245947 ("libbpf: Allow gaps in BPF program
sections to support overriden weak functions").

Add a check for detecting the overflow of `sec_off + prog_sz` to
bpf_object__init_prog to fix this issue.

[1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md

Fixes: 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions")
Reported-by: lmarch2 <2524158037@qq.com>
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md
Link: https://lore.kernel.org/bpf/20250415155014.397603-1-vmalik@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 20, 2025
commit c98cc97 upstream.

Running a modified trace-cmd record --nosplice where it does a mmap of the
ring buffer when '--nosplice' is set, caused the following lockdep splat:

 ======================================================
 WARNING: possible circular locking dependency detected
 6.15.0-rc7-test-00002-gfb7d03d8a82f #551 Not tainted
 ------------------------------------------------------
 trace-cmd/1113 is trying to acquire lock:
 ffff888100062888 (&buffer->mutex){+.+.}-{4:4}, at: ring_buffer_map+0x11c/0xe70

 but task is already holding lock:
 ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #5 (&cpu_buffer->mapping_lock){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        ring_buffer_map+0xcf/0xe70
        tracing_buffers_mmap+0x1c4/0x3b0
        __mmap_region+0xd8d/0x1f70
        do_mmap+0x9d7/0x1010
        vm_mmap_pgoff+0x20b/0x390
        ksys_mmap_pgoff+0x2e9/0x440
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #4 (&mm->mmap_lock){++++}-{4:4}:
        __might_fault+0xa5/0x110
        _copy_to_user+0x22/0x80
        _perf_ioctl+0x61b/0x1b70
        perf_ioctl+0x62/0x90
        __x64_sys_ioctl+0x134/0x190
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #3 (&cpuctx_mutex){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        perf_event_init_cpu+0x325/0x7c0
        perf_event_init+0x52a/0x5b0
        start_kernel+0x263/0x3e0
        x86_64_start_reservations+0x24/0x30
        x86_64_start_kernel+0x95/0xa0
        common_startup_64+0x13e/0x141

 -> #2 (pmus_lock){+.+.}-{4:4}:
        __mutex_lock+0x192/0x18c0
        perf_event_init_cpu+0xb7/0x7c0
        cpuhp_invoke_callback+0x2c0/0x1030
        __cpuhp_invoke_callback_range+0xbf/0x1f0
        _cpu_up+0x2e7/0x690
        cpu_up+0x117/0x170
        cpuhp_bringup_mask+0xd5/0x120
        bringup_nonboot_cpus+0x13d/0x170
        smp_init+0x2b/0xf0
        kernel_init_freeable+0x441/0x6d0
        kernel_init+0x1e/0x160
        ret_from_fork+0x34/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #1 (cpu_hotplug_lock){++++}-{0:0}:
        cpus_read_lock+0x2a/0xd0
        ring_buffer_resize+0x610/0x14e0
        __tracing_resize_ring_buffer.part.0+0x42/0x120
        tracing_set_tracer+0x7bd/0xa80
        tracing_set_trace_write+0x132/0x1e0
        vfs_write+0x21c/0xe80
        ksys_write+0xf9/0x1c0
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 -> #0 (&buffer->mutex){+.+.}-{4:4}:
        __lock_acquire+0x1405/0x2210
        lock_acquire+0x174/0x310
        __mutex_lock+0x192/0x18c0
        ring_buffer_map+0x11c/0xe70
        tracing_buffers_mmap+0x1c4/0x3b0
        __mmap_region+0xd8d/0x1f70
        do_mmap+0x9d7/0x1010
        vm_mmap_pgoff+0x20b/0x390
        ksys_mmap_pgoff+0x2e9/0x440
        do_syscall_64+0x79/0x1c0
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 other info that might help us debug this:

 Chain exists of:
   &buffer->mutex --> &mm->mmap_lock --> &cpu_buffer->mapping_lock

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&cpu_buffer->mapping_lock);
                                lock(&mm->mmap_lock);
                                lock(&cpu_buffer->mapping_lock);
   lock(&buffer->mutex);

  *** DEADLOCK ***

 2 locks held by trace-cmd/1113:
  #0: ffff888106b847e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x192/0x390
  #1: ffff888100a5f9f8 (&cpu_buffer->mapping_lock){+.+.}-{4:4}, at: ring_buffer_map+0xcf/0xe70

 stack backtrace:
 CPU: 5 UID: 0 PID: 1113 Comm: trace-cmd Not tainted 6.15.0-rc7-test-00002-gfb7d03d8a82f #551 PREEMPT
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x6e/0xa0
  print_circular_bug.cold+0x178/0x1be
  check_noncircular+0x146/0x160
  __lock_acquire+0x1405/0x2210
  lock_acquire+0x174/0x310
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? __mutex_lock+0x169/0x18c0
  __mutex_lock+0x192/0x18c0
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? function_trace_call+0x296/0x370
  ? __pfx___mutex_lock+0x10/0x10
  ? __pfx_function_trace_call+0x10/0x10
  ? __pfx___mutex_lock+0x10/0x10
  ? _raw_spin_unlock+0x2d/0x50
  ? ring_buffer_map+0x11c/0xe70
  ? ring_buffer_map+0x11c/0xe70
  ? __mutex_lock+0x5/0x18c0
  ring_buffer_map+0x11c/0xe70
  ? do_raw_spin_lock+0x12d/0x270
  ? find_held_lock+0x2b/0x80
  ? _raw_spin_unlock+0x2d/0x50
  ? rcu_is_watching+0x15/0xb0
  ? _raw_spin_unlock+0x2d/0x50
  ? trace_preempt_on+0xd0/0x110
  tracing_buffers_mmap+0x1c4/0x3b0
  __mmap_region+0xd8d/0x1f70
  ? ring_buffer_lock_reserve+0x99/0xff0
  ? __pfx___mmap_region+0x10/0x10
  ? ring_buffer_lock_reserve+0x99/0xff0
  ? __pfx_ring_buffer_lock_reserve+0x10/0x10
  ? __pfx_ring_buffer_lock_reserve+0x10/0x10
  ? bpf_lsm_mmap_addr+0x4/0x10
  ? security_mmap_addr+0x46/0xd0
  ? lock_is_held_type+0xd9/0x130
  do_mmap+0x9d7/0x1010
  ? 0xffffffffc0370095
  ? __pfx_do_mmap+0x10/0x10
  vm_mmap_pgoff+0x20b/0x390
  ? __pfx_vm_mmap_pgoff+0x10/0x10
  ? 0xffffffffc0370095
  ksys_mmap_pgoff+0x2e9/0x440
  do_syscall_64+0x79/0x1c0
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7fb0963a7de2
 Code: 00 00 00 0f 1f 44 00 00 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 3b 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 76 5b 5d c3 0f 1f 00 48 8b 05 e1 9f 0d 00 64
 RSP: 002b:00007ffdcc8fb878 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb0963a7de2
 RDX: 0000000000000001 RSI: 0000000000001000 RDI: 0000000000000000
 RBP: 0000000000000001 R08: 0000000000000006 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007ffdcc8fbe68 R14: 00007fb096628000 R15: 00005633e01a5c90
  </TASK>

The issue is that cpus_read_lock() is taken within buffer->mutex. The
memory mapped pages are taken with the mmap_lock held. The buffer->mutex
is taken within the cpu_buffer->mapping_lock. There's quite a chain with
all these locks, where the deadlock can be fixed by moving the
cpus_read_lock() outside the taking of the buffer->mutex.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250527105820.0f45d045@gandalf.local.home
Fixes: 117c392 ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
donald pushed a commit that referenced this issue Jun 20, 2025
[ Upstream commit ee684de ]

As shown in [1], it is possible to corrupt a BPF ELF file such that
arbitrary BPF instructions are loaded by libbpf. This can be done by
setting a symbol (BPF program) section offset to a large (unsigned)
number such that <section start + symbol offset> overflows and points
before the section data in the memory.

Consider the situation below where:
- prog_start = sec_start + symbol_offset    <-- size_t overflow here
- prog_end   = prog_start + prog_size

    prog_start        sec_start        prog_end        sec_end
        |                |                 |              |
        v                v                 v              v
    .....................|################################|............

The report in [1] also provides a corrupted BPF ELF which can be used as
a reproducer:

    $ readelf -S crash
    Section Headers:
      [Nr] Name              Type             Address           Offset
           Size              EntSize          Flags  Link  Info  Align
    ...
      [ 2] uretprobe.mu[...] PROGBITS         0000000000000000  00000040
           0000000000000068  0000000000000000  AX       0     0     8

    $ readelf -s crash
    Symbol table '.symtab' contains 8 entries:
       Num:    Value          Size Type    Bind   Vis      Ndx Name
    ...
         6: ffffffffffffffb8   104 FUNC    GLOBAL DEFAULT    2 handle_tp

Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will
point before the actual memory where section 2 is allocated.

This is also reported by AddressSanitizer:

    =================================================================
    ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490
    READ of size 104 at 0x7c7302fe0000 thread T0
        #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76)
        #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856
        #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928
        #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930
        #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067
        #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090
        #6 0x000000400c16 in main /poc/poc.c:8
        #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4)
        #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667)
        #9 0x000000400b34 in _start (/poc/poc+0x400b34)

    0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8)
    allocated by thread T0 here:
        #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b)
        #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600)
        #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018)
        #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740

The problem here is that currently, libbpf only checks that the program
end is within the section bounds. There used to be a check
`while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was
removed by commit 6245947 ("libbpf: Allow gaps in BPF program
sections to support overriden weak functions").

Add a check for detecting the overflow of `sec_off + prog_sz` to
bpf_object__init_prog to fix this issue.

[1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md

Fixes: 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions")
Reported-by: lmarch2 <2524158037@qq.com>
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md
Link: https://lore.kernel.org/bpf/20250415155014.397603-1-vmalik@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 28, 2025
[ Upstream commit d4b2173 ]

Create necessary functions to encode/decode aarch64 barrier
instructions.

DSB needs special case handling as it has multiple encodings.

Signed-off-by: Julien Thierry <jthierry@redhat.com>
Link: https://lore.kernel.org/r/20210303170536.1838032-7-jthierry@redhat.com
[will: Don't reject DSB #4]
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
donald pushed a commit that referenced this issue Jun 28, 2025
commit be6e843 upstream.

When migrating a THP, concurrent access to the PMD migration entry during
a deferred split scan can lead to an invalid address access, as
illustrated below.  To prevent this invalid access, it is necessary to
check the PMD migration entry and return early.  In this context, there is
no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the
equality of the target folio.  Since the PMD migration entry is locked, it
cannot be served as the target.

Mailing list discussion and explanation from Hugh Dickins: "An anon_vma
lookup points to a location which may contain the folio of interest, but
might instead contain another folio: and weeding out those other folios is
precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of
replacing the wrong folio" comment a few lines above it) is for."

BUG: unable to handle page fault for address: ffffea60001db008
CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60
Call Trace:
<TASK>
try_to_migrate_one+0x28c/0x3730
rmap_walk_anon+0x4f6/0x770
unmap_folio+0x196/0x1f0
split_huge_page_to_list_to_order+0x9f6/0x1560
deferred_split_scan+0xac5/0x12a0
shrinker_debugfs_scan_write+0x376/0x470
full_proxy_write+0x15c/0x220
vfs_write+0x2fc/0xcb0
ksys_write+0x146/0x250
do_syscall_64+0x6a/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e

The bug is found by syzkaller on an internal kernel, then confirmed on
upstream.

Link: https://lkml.kernel.org/r/20250421113536.3682201-1-gavinguo@igalia.com
Link: https://lore.kernel.org/all/20250414072737.1698513-1-gavinguo@igalia.com/
Link: https://lore.kernel.org/all/20250418085802.2973519-1-gavinguo@igalia.com/
Fixes: 84c3fc4 ("mm: thp: check pmd migration entry in common path")
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Cc: Florent Revest <revest@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[gavin: backport the migration checking logic to __split_huge_pmd]
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
donald pushed a commit that referenced this issue Jun 28, 2025
[ Upstream commit ee684de ]

As shown in [1], it is possible to corrupt a BPF ELF file such that
arbitrary BPF instructions are loaded by libbpf. This can be done by
setting a symbol (BPF program) section offset to a large (unsigned)
number such that <section start + symbol offset> overflows and points
before the section data in the memory.

Consider the situation below where:
- prog_start = sec_start + symbol_offset    <-- size_t overflow here
- prog_end   = prog_start + prog_size

    prog_start        sec_start        prog_end        sec_end
        |                |                 |              |
        v                v                 v              v
    .....................|################################|............

The report in [1] also provides a corrupted BPF ELF which can be used as
a reproducer:

    $ readelf -S crash
    Section Headers:
      [Nr] Name              Type             Address           Offset
           Size              EntSize          Flags  Link  Info  Align
    ...
      [ 2] uretprobe.mu[...] PROGBITS         0000000000000000  00000040
           0000000000000068  0000000000000000  AX       0     0     8

    $ readelf -s crash
    Symbol table '.symtab' contains 8 entries:
       Num:    Value          Size Type    Bind   Vis      Ndx Name
    ...
         6: ffffffffffffffb8   104 FUNC    GLOBAL DEFAULT    2 handle_tp

Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will
point before the actual memory where section 2 is allocated.

This is also reported by AddressSanitizer:

    =================================================================
    ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490
    READ of size 104 at 0x7c7302fe0000 thread T0
        #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76)
        #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856
        #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928
        #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930
        #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067
        #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090
        #6 0x000000400c16 in main /poc/poc.c:8
        #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4)
        #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667)
        #9 0x000000400b34 in _start (/poc/poc+0x400b34)

    0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8)
    allocated by thread T0 here:
        #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b)
        #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600)
        #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018)
        #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740

The problem here is that currently, libbpf only checks that the program
end is within the section bounds. There used to be a check
`while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was
removed by commit 6245947 ("libbpf: Allow gaps in BPF program
sections to support overriden weak functions").

Add a check for detecting the overflow of `sec_off + prog_sz` to
bpf_object__init_prog to fix this issue.

[1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md

Fixes: 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions")
Reported-by: lmarch2 <2524158037@qq.com>
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md
Link: https://lore.kernel.org/bpf/20250415155014.397603-1-vmalik@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 28, 2025
commit be6e843 upstream.

When migrating a THP, concurrent access to the PMD migration entry during
a deferred split scan can lead to an invalid address access, as
illustrated below.  To prevent this invalid access, it is necessary to
check the PMD migration entry and return early.  In this context, there is
no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the
equality of the target folio.  Since the PMD migration entry is locked, it
cannot be served as the target.

Mailing list discussion and explanation from Hugh Dickins: "An anon_vma
lookup points to a location which may contain the folio of interest, but
might instead contain another folio: and weeding out those other folios is
precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of
replacing the wrong folio" comment a few lines above it) is for."

BUG: unable to handle page fault for address: ffffea60001db008
CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60
Call Trace:
<TASK>
try_to_migrate_one+0x28c/0x3730
rmap_walk_anon+0x4f6/0x770
unmap_folio+0x196/0x1f0
split_huge_page_to_list_to_order+0x9f6/0x1560
deferred_split_scan+0xac5/0x12a0
shrinker_debugfs_scan_write+0x376/0x470
full_proxy_write+0x15c/0x220
vfs_write+0x2fc/0xcb0
ksys_write+0x146/0x250
do_syscall_64+0x6a/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e

The bug is found by syzkaller on an internal kernel, then confirmed on
upstream.

Link: https://lkml.kernel.org/r/20250421113536.3682201-1-gavinguo@igalia.com
Link: https://lore.kernel.org/all/20250414072737.1698513-1-gavinguo@igalia.com/
Link: https://lore.kernel.org/all/20250418085802.2973519-1-gavinguo@igalia.com/
Fixes: 84c3fc4 ("mm: thp: check pmd migration entry in common path")
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Cc: Florent Revest <revest@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[gavin: backport the migration checking logic to __split_huge_pmd]
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
donald pushed a commit that referenced this issue Jun 28, 2025
[ Upstream commit ee684de ]

As shown in [1], it is possible to corrupt a BPF ELF file such that
arbitrary BPF instructions are loaded by libbpf. This can be done by
setting a symbol (BPF program) section offset to a large (unsigned)
number such that <section start + symbol offset> overflows and points
before the section data in the memory.

Consider the situation below where:
- prog_start = sec_start + symbol_offset    <-- size_t overflow here
- prog_end   = prog_start + prog_size

    prog_start        sec_start        prog_end        sec_end
        |                |                 |              |
        v                v                 v              v
    .....................|################################|............

The report in [1] also provides a corrupted BPF ELF which can be used as
a reproducer:

    $ readelf -S crash
    Section Headers:
      [Nr] Name              Type             Address           Offset
           Size              EntSize          Flags  Link  Info  Align
    ...
      [ 2] uretprobe.mu[...] PROGBITS         0000000000000000  00000040
           0000000000000068  0000000000000000  AX       0     0     8

    $ readelf -s crash
    Symbol table '.symtab' contains 8 entries:
       Num:    Value          Size Type    Bind   Vis      Ndx Name
    ...
         6: ffffffffffffffb8   104 FUNC    GLOBAL DEFAULT    2 handle_tp

Here, the handle_tp prog has section offset ffffffffffffffb8, i.e. will
point before the actual memory where section 2 is allocated.

This is also reported by AddressSanitizer:

    =================================================================
    ==1232==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x7c7302fe0000 at pc 0x7fc3046e4b77 bp 0x7ffe64677cd0 sp 0x7ffe64677490
    READ of size 104 at 0x7c7302fe0000 thread T0
        #0 0x7fc3046e4b76 in memcpy (/lib64/libasan.so.8+0xe4b76)
        #1 0x00000040df3e in bpf_object__init_prog /src/libbpf/src/libbpf.c:856
        #2 0x00000040df3e in bpf_object__add_programs /src/libbpf/src/libbpf.c:928
        #3 0x00000040df3e in bpf_object__elf_collect /src/libbpf/src/libbpf.c:3930
        #4 0x00000040df3e in bpf_object_open /src/libbpf/src/libbpf.c:8067
        #5 0x00000040f176 in bpf_object__open_file /src/libbpf/src/libbpf.c:8090
        #6 0x000000400c16 in main /poc/poc.c:8
        #7 0x7fc3043d25b4 in __libc_start_call_main (/lib64/libc.so.6+0x35b4)
        #8 0x7fc3043d2667 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x3667)
        #9 0x000000400b34 in _start (/poc/poc+0x400b34)

    0x7c7302fe0000 is located 64 bytes before 104-byte region [0x7c7302fe0040,0x7c7302fe00a8)
    allocated by thread T0 here:
        #0 0x7fc3046e716b in malloc (/lib64/libasan.so.8+0xe716b)
        #1 0x7fc3045ee600 in __libelf_set_rawdata_wrlock (/lib64/libelf.so.1+0xb600)
        #2 0x7fc3045ef018 in __elf_getdata_rdlock (/lib64/libelf.so.1+0xc018)
        #3 0x00000040642f in elf_sec_data /src/libbpf/src/libbpf.c:3740

The problem here is that currently, libbpf only checks that the program
end is within the section bounds. There used to be a check
`while (sec_off < sec_sz)` in bpf_object__add_programs, however, it was
removed by commit 6245947 ("libbpf: Allow gaps in BPF program
sections to support overriden weak functions").

Add a check for detecting the overflow of `sec_off + prog_sz` to
bpf_object__init_prog to fix this issue.

[1] https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md

Fixes: 6245947 ("libbpf: Allow gaps in BPF program sections to support overriden weak functions")
Reported-by: lmarch2 <2524158037@qq.com>
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://github.com/lmarch2/poc/blob/main/libbpf/libbpf.md
Link: https://lore.kernel.org/bpf/20250415155014.397603-1-vmalik@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 28, 2025
commit be6e843 upstream.

When migrating a THP, concurrent access to the PMD migration entry during
a deferred split scan can lead to an invalid address access, as
illustrated below.  To prevent this invalid access, it is necessary to
check the PMD migration entry and return early.  In this context, there is
no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the
equality of the target folio.  Since the PMD migration entry is locked, it
cannot be served as the target.

Mailing list discussion and explanation from Hugh Dickins: "An anon_vma
lookup points to a location which may contain the folio of interest, but
might instead contain another folio: and weeding out those other folios is
precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of
replacing the wrong folio" comment a few lines above it) is for."

BUG: unable to handle page fault for address: ffffea60001db008
CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60
Call Trace:
<TASK>
try_to_migrate_one+0x28c/0x3730
rmap_walk_anon+0x4f6/0x770
unmap_folio+0x196/0x1f0
split_huge_page_to_list_to_order+0x9f6/0x1560
deferred_split_scan+0xac5/0x12a0
shrinker_debugfs_scan_write+0x376/0x470
full_proxy_write+0x15c/0x220
vfs_write+0x2fc/0xcb0
ksys_write+0x146/0x250
do_syscall_64+0x6a/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e

The bug is found by syzkaller on an internal kernel, then confirmed on
upstream.

Link: https://lkml.kernel.org/r/20250421113536.3682201-1-gavinguo@igalia.com
Link: https://lore.kernel.org/all/20250414072737.1698513-1-gavinguo@igalia.com/
Link: https://lore.kernel.org/all/20250418085802.2973519-1-gavinguo@igalia.com/
Fixes: 84c3fc4 ("mm: thp: check pmd migration entry in common path")
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Cc: Florent Revest <revest@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[gavin: backport the migration checking logic to __split_huge_pmd]
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
donald pushed a commit that referenced this issue Jun 28, 2025
[ Upstream commit eedf3e3 ]

ACPICA commit 1c28da2242783579d59767617121035dafba18c3

This was originally done in NetBSD:
https://github.com/NetBSD/src/commit/b69d1ac3f7702f67edfe412e4392f77d09804910
and is the correct alternative to the smattering of `memcpy`s I
previously contributed to this repository.

This also sidesteps the newly strict checks added in UBSAN:
https://github.com/llvm/llvm-project/commit/792674400f6f04a074a3827349ed0e2ac10067f6

Before this change we see the following UBSAN stack trace in Fuchsia:

  #0    0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e
  #1.2  0x000021982bc4af3c in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x41f3c
  #1.1  0x000021982bc4af3c in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x41f3c
  #1    0x000021982bc4af3c in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:395 <libclang_rt.asan.so>+0x41f3c
  #2    0x000021982bc4bb6f in handletype_mismatch_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:137 <libclang_rt.asan.so>+0x42b6f
  #3    0x000021982bc4b723 in __ubsan_handle_type_mismatch_v1 compiler-rt/lib/ubsan/ubsan_handlers.cpp:142 <libclang_rt.asan.so>+0x42723
  #4    0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e
  #5    0x000021afcfdf2089 in acpi_rs_convert_aml_to_resource(struct acpi_resource*, union aml_resource*, struct acpi_rsconvert_info*) ../../third_party/acpica/source/components/resources/rsmisc.c:355 <platform-bus-x86.so>+0x6b2089
  #6    0x000021afcfded169 in acpi_rs_convert_aml_to_resources(u8*, u32, u32, u8, void**) ../../third_party/acpica/source/components/resources/rslist.c:137 <platform-bus-x86.so>+0x6ad169
  #7    0x000021afcfe2d24a in acpi_ut_walk_aml_resources(struct acpi_walk_state*, u8*, acpi_size, acpi_walk_aml_callback, void**) ../../third_party/acpica/source/components/utilities/utresrc.c:237 <platform-bus-x86.so>+0x6ed24a
  #8    0x000021afcfde66b7 in acpi_rs_create_resource_list(union acpi_operand_object*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rscreate.c:199 <platform-bus-x86.so>+0x6a66b7
  #9    0x000021afcfdf6979 in acpi_rs_get_method_data(acpi_handle, const char*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rsutils.c:770 <platform-bus-x86.so>+0x6b6979
  #10   0x000021afcfdf708f in acpi_walk_resources(acpi_handle, char*, acpi_walk_resource_callback, void*) ../../third_party/acpica/source/components/resources/rsxface.c:731 <platform-bus-x86.so>+0x6b708f
  #11   0x000021afcfa95dcf in acpi::acpi_impl::walk_resources(acpi::acpi_impl*, acpi_handle, const char*, acpi::Acpi::resources_callable) ../../src/devices/board/lib/acpi/acpi-impl.cc:41 <platform-bus-x86.so>+0x355dcf
  #12   0x000021afcfaa8278 in acpi::device_builder::gather_resources(acpi::device_builder*, acpi::Acpi*, fidl::any_arena&, acpi::Manager*, acpi::device_builder::gather_resources_callback) ../../src/devices/board/lib/acpi/device-builder.cc:84 <platform-bus-x86.so>+0x368278
  #13   0x000021afcfbddb87 in acpi::Manager::configure_discovered_devices(acpi::Manager*) ../../src/devices/board/lib/acpi/manager.cc:75 <platform-bus-x86.so>+0x49db87
  #14   0x000021afcf99091d in publish_acpi_devices(acpi::Manager*, zx_device_t*, zx_device_t*) ../../src/devices/board/drivers/x86/acpi-nswalk.cc:95 <platform-bus-x86.so>+0x25091d
  #15   0x000021afcf9c1d4e in x86::X86::do_init(x86::X86*) ../../src/devices/board/drivers/x86/x86.cc:60 <platform-bus-x86.so>+0x281d4e
  #16   0x000021afcf9e33ad in λ(x86::X86::ddk_init::(anon class)*) ../../src/devices/board/drivers/x86/x86.cc:77 <platform-bus-x86.so>+0x2a33ad
  #17   0x000021afcf9e313e in fit::internal::target<(lambda at../../src/devices/board/drivers/x86/x86.cc:76:19), false, false, std::__2::allocator<std::byte>, void>::invoke(void*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:183 <platform-bus-x86.so>+0x2a313e
  #18   0x000021afcfbab4c7 in fit::internal::function_base<16UL, false, void(), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <platform-bus-x86.so>+0x46b4c7
  #19   0x000021afcfbab342 in fit::function_impl<16UL, false, void(), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/function.h:315 <platform-bus-x86.so>+0x46b342
  #20   0x000021afcfcd98c3 in async::internal::retained_task::Handler(async_dispatcher_t*, async_task_t*, zx_status_t) ../../sdk/lib/async/task.cc:24 <platform-bus-x86.so>+0x5998c3
  #21   0x00002290f9924616 in λ(const driver_runtime::Dispatcher::post_task::(anon class)*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/dispatcher.cc:789 <libdriver_runtime.so>+0x10a616
  #22   0x00002290f9924323 in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:788:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int>::invoke(void*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0x10a323
  #23   0x00002290f9904b76 in fit::internal::function_base<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xeab76
  #24   0x00002290f9904831 in fit::callback_impl<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::operator()(fit::callback_impl<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/function.h:471 <libdriver_runtime.so>+0xea831
  #25   0x00002290f98d5adc in driver_runtime::callback_request::Call(driver_runtime::callback_request*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/callback_request.h:74 <libdriver_runtime.so>+0xbbadc
  #26   0x00002290f98e1e58 in driver_runtime::Dispatcher::dispatch_callback(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >) ../../src/devices/bin/driver_runtime/dispatcher.cc:1248 <libdriver_runtime.so>+0xc7e58
  #27   0x00002290f98e4159 in driver_runtime::Dispatcher::dispatch_callbacks(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:1308 <libdriver_runtime.so>+0xca159
  #28   0x00002290f9918414 in λ(const driver_runtime::Dispatcher::create_with_adder::(anon class)*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:353 <libdriver_runtime.so>+0xfe414
  #29   0x00002290f991812d in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:351:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>>::invoke(void*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0xfe12d
  #30   0x00002290f9906fc7 in fit::internal::function_base<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xecfc7
  #31   0x00002290f9906c66 in fit::function_impl<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/function.h:315 <libdriver_runtime.so>+0xecc66
  #32   0x00002290f98e73d9 in driver_runtime::Dispatcher::event_waiter::invoke_callback(driver_runtime::Dispatcher::event_waiter*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.h:543 <libdriver_runtime.so>+0xcd3d9
  #33   0x00002290f98e700d in driver_runtime::Dispatcher::event_waiter::handle_event(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/dispatcher.cc:1442 <libdriver_runtime.so>+0xcd00d
  #34   0x00002290f9918983 in async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event(async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>*, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/async_loop_owned_event_handler.h:59 <libdriver_runtime.so>+0xfe983
  #35   0x00002290f9918b9e in async::wait_method<async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>, &async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event>::call_handler(async_dispatcher_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async/include/lib/async/cpp/wait.h:201 <libdriver_runtime.so>+0xfeb9e
  #36   0x00002290f99bf509 in async_loop_dispatch_wait(async_loop_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async-loop/loop.c:394 <libdriver_runtime.so>+0x1a5509
  #37   0x00002290f99b9958 in async_loop_run_once(async_loop_t*, zx_time_t) ../../sdk/lib/async-loop/loop.c:343 <libdriver_runtime.so>+0x19f958
  #38   0x00002290f99b9247 in async_loop_run(async_loop_t*, zx_time_t, _Bool) ../../sdk/lib/async-loop/loop.c:301 <libdriver_runtime.so>+0x19f247
  #39   0x00002290f99ba962 in async_loop_run_thread(void*) ../../sdk/lib/async-loop/loop.c:860 <libdriver_runtime.so>+0x1a0962
  #40   0x000041afd176ef30 in start_c11(void*) ../../zircon/third_party/ulib/musl/pthread/pthread_create.c:63 <libc.so>+0x84f30
  #41   0x000041afd18a448d in thread_trampoline(uintptr_t, uintptr_t) ../../zircon/system/ulib/runtime/thread.cc:100 <libc.so>+0x1ba48d

Link: https://github.com/acpica/acpica/commit/1c28da22
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/4664267.LvFx2qVVIh@rjwysocki.net
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
[ rjw: Pick up the tag from Tamir ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 28, 2025
[ Upstream commit 1e9ac33 ]

Before the commit under the Fixes tag below, bnxt_ulp_stop() and
bnxt_ulp_start() were always invoked in pairs.  After that commit,
the new bnxt_ulp_restart() can be invoked after bnxt_ulp_stop()
has been called.  This may result in the RoCE driver's aux driver
.suspend() method being invoked twice.  The 2nd bnxt_re_suspend()
call will crash when it dereferences a NULL pointer:

(NULL ib_device): Handle device suspend call
BUG: kernel NULL pointer dereference, address: 0000000000000b78
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP PTI
CPU: 20 UID: 0 PID: 181 Comm: kworker/u96:5 Tainted: G S                  6.15.0-rc1 #4 PREEMPT(voluntary)
Tainted: [S]=CPU_OUT_OF_SPEC
Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017
Workqueue: bnxt_pf_wq bnxt_sp_task [bnxt_en]
RIP: 0010:bnxt_re_suspend+0x45/0x1f0 [bnxt_re]
Code: 8b 05 a7 3c 5b f5 48 89 44 24 18 31 c0 49 8b 5c 24 08 4d 8b 2c 24 e8 ea 06 0a f4 48 c7 c6 04 60 52 c0 48 89 df e8 1b ce f9 ff <48> 8b 83 78 0b 00 00 48 8b 80 38 03 00 00 a8 40 0f 85 b5 00 00 00
RSP: 0018:ffffa2e84084fd88 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffffb4b6b934 RDI: 00000000ffffffff
RBP: ffffa1760954c9c0 R08: 0000000000000000 R09: c0000000ffffdfff
R10: 0000000000000001 R11: ffffa2e84084fb50 R12: ffffa176031ef070
R13: ffffa17609775000 R14: ffffa17603adc180 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffffa17daa397000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000b78 CR3: 00000004aaa30003 CR4: 00000000003706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bnxt_ulp_stop+0x69/0x90 [bnxt_en]
bnxt_sp_task+0x678/0x920 [bnxt_en]
? __schedule+0x514/0xf50
process_scheduled_works+0x9d/0x400
worker_thread+0x11c/0x260
? __pfx_worker_thread+0x10/0x10
kthread+0xfe/0x1e0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2b/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30

Check the BNXT_EN_FLAG_ULP_STOPPED flag and do not proceed if the flag
is already set.  This will preserve the original symmetrical
bnxt_ulp_stop() and bnxt_ulp_start().

Also, inside bnxt_ulp_start(), clear the BNXT_EN_FLAG_ULP_STOPPED
flag after taking the mutex to avoid any race condition.  And for
symmetry, only proceed in bnxt_ulp_start() if the
BNXT_EN_FLAG_ULP_STOPPED is set.

Fixes: 3c163f3 ("bnxt_en: Optimize recovery path ULP locking in the driver")
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Co-developed-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250613231841.377988-2-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 28, 2025
[ Upstream commit eedf3e3 ]

ACPICA commit 1c28da2242783579d59767617121035dafba18c3

This was originally done in NetBSD:
https://github.com/NetBSD/src/commit/b69d1ac3f7702f67edfe412e4392f77d09804910
and is the correct alternative to the smattering of `memcpy`s I
previously contributed to this repository.

This also sidesteps the newly strict checks added in UBSAN:
https://github.com/llvm/llvm-project/commit/792674400f6f04a074a3827349ed0e2ac10067f6

Before this change we see the following UBSAN stack trace in Fuchsia:

  #0    0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e
  #1.2  0x000021982bc4af3c in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x41f3c
  #1.1  0x000021982bc4af3c in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x41f3c
  #1    0x000021982bc4af3c in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:395 <libclang_rt.asan.so>+0x41f3c
  #2    0x000021982bc4bb6f in handletype_mismatch_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:137 <libclang_rt.asan.so>+0x42b6f
  #3    0x000021982bc4b723 in __ubsan_handle_type_mismatch_v1 compiler-rt/lib/ubsan/ubsan_handlers.cpp:142 <libclang_rt.asan.so>+0x42723
  #4    0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e
  #5    0x000021afcfdf2089 in acpi_rs_convert_aml_to_resource(struct acpi_resource*, union aml_resource*, struct acpi_rsconvert_info*) ../../third_party/acpica/source/components/resources/rsmisc.c:355 <platform-bus-x86.so>+0x6b2089
  #6    0x000021afcfded169 in acpi_rs_convert_aml_to_resources(u8*, u32, u32, u8, void**) ../../third_party/acpica/source/components/resources/rslist.c:137 <platform-bus-x86.so>+0x6ad169
  #7    0x000021afcfe2d24a in acpi_ut_walk_aml_resources(struct acpi_walk_state*, u8*, acpi_size, acpi_walk_aml_callback, void**) ../../third_party/acpica/source/components/utilities/utresrc.c:237 <platform-bus-x86.so>+0x6ed24a
  #8    0x000021afcfde66b7 in acpi_rs_create_resource_list(union acpi_operand_object*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rscreate.c:199 <platform-bus-x86.so>+0x6a66b7
  #9    0x000021afcfdf6979 in acpi_rs_get_method_data(acpi_handle, const char*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rsutils.c:770 <platform-bus-x86.so>+0x6b6979
  #10   0x000021afcfdf708f in acpi_walk_resources(acpi_handle, char*, acpi_walk_resource_callback, void*) ../../third_party/acpica/source/components/resources/rsxface.c:731 <platform-bus-x86.so>+0x6b708f
  #11   0x000021afcfa95dcf in acpi::acpi_impl::walk_resources(acpi::acpi_impl*, acpi_handle, const char*, acpi::Acpi::resources_callable) ../../src/devices/board/lib/acpi/acpi-impl.cc:41 <platform-bus-x86.so>+0x355dcf
  #12   0x000021afcfaa8278 in acpi::device_builder::gather_resources(acpi::device_builder*, acpi::Acpi*, fidl::any_arena&, acpi::Manager*, acpi::device_builder::gather_resources_callback) ../../src/devices/board/lib/acpi/device-builder.cc:84 <platform-bus-x86.so>+0x368278
  #13   0x000021afcfbddb87 in acpi::Manager::configure_discovered_devices(acpi::Manager*) ../../src/devices/board/lib/acpi/manager.cc:75 <platform-bus-x86.so>+0x49db87
  #14   0x000021afcf99091d in publish_acpi_devices(acpi::Manager*, zx_device_t*, zx_device_t*) ../../src/devices/board/drivers/x86/acpi-nswalk.cc:95 <platform-bus-x86.so>+0x25091d
  #15   0x000021afcf9c1d4e in x86::X86::do_init(x86::X86*) ../../src/devices/board/drivers/x86/x86.cc:60 <platform-bus-x86.so>+0x281d4e
  #16   0x000021afcf9e33ad in λ(x86::X86::ddk_init::(anon class)*) ../../src/devices/board/drivers/x86/x86.cc:77 <platform-bus-x86.so>+0x2a33ad
  #17   0x000021afcf9e313e in fit::internal::target<(lambda at../../src/devices/board/drivers/x86/x86.cc:76:19), false, false, std::__2::allocator<std::byte>, void>::invoke(void*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:183 <platform-bus-x86.so>+0x2a313e
  #18   0x000021afcfbab4c7 in fit::internal::function_base<16UL, false, void(), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <platform-bus-x86.so>+0x46b4c7
  #19   0x000021afcfbab342 in fit::function_impl<16UL, false, void(), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/function.h:315 <platform-bus-x86.so>+0x46b342
  #20   0x000021afcfcd98c3 in async::internal::retained_task::Handler(async_dispatcher_t*, async_task_t*, zx_status_t) ../../sdk/lib/async/task.cc:24 <platform-bus-x86.so>+0x5998c3
  #21   0x00002290f9924616 in λ(const driver_runtime::Dispatcher::post_task::(anon class)*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/dispatcher.cc:789 <libdriver_runtime.so>+0x10a616
  #22   0x00002290f9924323 in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:788:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int>::invoke(void*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0x10a323
  #23   0x00002290f9904b76 in fit::internal::function_base<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xeab76
  #24   0x00002290f9904831 in fit::callback_impl<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::operator()(fit::callback_impl<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/function.h:471 <libdriver_runtime.so>+0xea831
  #25   0x00002290f98d5adc in driver_runtime::callback_request::Call(driver_runtime::callback_request*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/callback_request.h:74 <libdriver_runtime.so>+0xbbadc
  #26   0x00002290f98e1e58 in driver_runtime::Dispatcher::dispatch_callback(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >) ../../src/devices/bin/driver_runtime/dispatcher.cc:1248 <libdriver_runtime.so>+0xc7e58
  #27   0x00002290f98e4159 in driver_runtime::Dispatcher::dispatch_callbacks(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:1308 <libdriver_runtime.so>+0xca159
  #28   0x00002290f9918414 in λ(const driver_runtime::Dispatcher::create_with_adder::(anon class)*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:353 <libdriver_runtime.so>+0xfe414
  #29   0x00002290f991812d in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:351:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>>::invoke(void*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0xfe12d
  #30   0x00002290f9906fc7 in fit::internal::function_base<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xecfc7
  #31   0x00002290f9906c66 in fit::function_impl<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/function.h:315 <libdriver_runtime.so>+0xecc66
  #32   0x00002290f98e73d9 in driver_runtime::Dispatcher::event_waiter::invoke_callback(driver_runtime::Dispatcher::event_waiter*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.h:543 <libdriver_runtime.so>+0xcd3d9
  #33   0x00002290f98e700d in driver_runtime::Dispatcher::event_waiter::handle_event(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/dispatcher.cc:1442 <libdriver_runtime.so>+0xcd00d
  #34   0x00002290f9918983 in async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event(async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>*, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/async_loop_owned_event_handler.h:59 <libdriver_runtime.so>+0xfe983
  #35   0x00002290f9918b9e in async::wait_method<async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>, &async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event>::call_handler(async_dispatcher_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async/include/lib/async/cpp/wait.h:201 <libdriver_runtime.so>+0xfeb9e
  #36   0x00002290f99bf509 in async_loop_dispatch_wait(async_loop_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async-loop/loop.c:394 <libdriver_runtime.so>+0x1a5509
  #37   0x00002290f99b9958 in async_loop_run_once(async_loop_t*, zx_time_t) ../../sdk/lib/async-loop/loop.c:343 <libdriver_runtime.so>+0x19f958
  #38   0x00002290f99b9247 in async_loop_run(async_loop_t*, zx_time_t, _Bool) ../../sdk/lib/async-loop/loop.c:301 <libdriver_runtime.so>+0x19f247
  #39   0x00002290f99ba962 in async_loop_run_thread(void*) ../../sdk/lib/async-loop/loop.c:860 <libdriver_runtime.so>+0x1a0962
  #40   0x000041afd176ef30 in start_c11(void*) ../../zircon/third_party/ulib/musl/pthread/pthread_create.c:63 <libc.so>+0x84f30
  #41   0x000041afd18a448d in thread_trampoline(uintptr_t, uintptr_t) ../../zircon/system/ulib/runtime/thread.cc:100 <libc.so>+0x1ba48d

Link: https://github.com/acpica/acpica/commit/1c28da22
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/4664267.LvFx2qVVIh@rjwysocki.net
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
[ rjw: Pick up the tag from Tamir ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 28, 2025
[ Upstream commit 1e9ac33 ]

Before the commit under the Fixes tag below, bnxt_ulp_stop() and
bnxt_ulp_start() were always invoked in pairs.  After that commit,
the new bnxt_ulp_restart() can be invoked after bnxt_ulp_stop()
has been called.  This may result in the RoCE driver's aux driver
.suspend() method being invoked twice.  The 2nd bnxt_re_suspend()
call will crash when it dereferences a NULL pointer:

(NULL ib_device): Handle device suspend call
BUG: kernel NULL pointer dereference, address: 0000000000000b78
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP PTI
CPU: 20 UID: 0 PID: 181 Comm: kworker/u96:5 Tainted: G S                  6.15.0-rc1 #4 PREEMPT(voluntary)
Tainted: [S]=CPU_OUT_OF_SPEC
Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017
Workqueue: bnxt_pf_wq bnxt_sp_task [bnxt_en]
RIP: 0010:bnxt_re_suspend+0x45/0x1f0 [bnxt_re]
Code: 8b 05 a7 3c 5b f5 48 89 44 24 18 31 c0 49 8b 5c 24 08 4d 8b 2c 24 e8 ea 06 0a f4 48 c7 c6 04 60 52 c0 48 89 df e8 1b ce f9 ff <48> 8b 83 78 0b 00 00 48 8b 80 38 03 00 00 a8 40 0f 85 b5 00 00 00
RSP: 0018:ffffa2e84084fd88 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffffb4b6b934 RDI: 00000000ffffffff
RBP: ffffa1760954c9c0 R08: 0000000000000000 R09: c0000000ffffdfff
R10: 0000000000000001 R11: ffffa2e84084fb50 R12: ffffa176031ef070
R13: ffffa17609775000 R14: ffffa17603adc180 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffffa17daa397000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000b78 CR3: 00000004aaa30003 CR4: 00000000003706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bnxt_ulp_stop+0x69/0x90 [bnxt_en]
bnxt_sp_task+0x678/0x920 [bnxt_en]
? __schedule+0x514/0xf50
process_scheduled_works+0x9d/0x400
worker_thread+0x11c/0x260
? __pfx_worker_thread+0x10/0x10
kthread+0xfe/0x1e0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2b/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30

Check the BNXT_EN_FLAG_ULP_STOPPED flag and do not proceed if the flag
is already set.  This will preserve the original symmetrical
bnxt_ulp_stop() and bnxt_ulp_start().

Also, inside bnxt_ulp_start(), clear the BNXT_EN_FLAG_ULP_STOPPED
flag after taking the mutex to avoid any race condition.  And for
symmetry, only proceed in bnxt_ulp_start() if the
BNXT_EN_FLAG_ULP_STOPPED is set.

Fixes: 3c163f3 ("bnxt_en: Optimize recovery path ULP locking in the driver")
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Co-developed-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250613231841.377988-2-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
donald pushed a commit that referenced this issue Jun 28, 2025
commit be6e843 upstream.

When migrating a THP, concurrent access to the PMD migration entry during
a deferred split scan can lead to an invalid address access, as
illustrated below.  To prevent this invalid access, it is necessary to
check the PMD migration entry and return early.  In this context, there is
no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the
equality of the target folio.  Since the PMD migration entry is locked, it
cannot be served as the target.

Mailing list discussion and explanation from Hugh Dickins: "An anon_vma
lookup points to a location which may contain the folio of interest, but
might instead contain another folio: and weeding out those other folios is
precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of
replacing the wrong folio" comment a few lines above it) is for."

BUG: unable to handle page fault for address: ffffea60001db008
CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60
Call Trace:
<TASK>
try_to_migrate_one+0x28c/0x3730
rmap_walk_anon+0x4f6/0x770
unmap_folio+0x196/0x1f0
split_huge_page_to_list_to_order+0x9f6/0x1560
deferred_split_scan+0xac5/0x12a0
shrinker_debugfs_scan_write+0x376/0x470
full_proxy_write+0x15c/0x220
vfs_write+0x2fc/0xcb0
ksys_write+0x146/0x250
do_syscall_64+0x6a/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e

The bug is found by syzkaller on an internal kernel, then confirmed on
upstream.

Link: https://lkml.kernel.org/r/20250421113536.3682201-1-gavinguo@igalia.com
Link: https://lore.kernel.org/all/20250414072737.1698513-1-gavinguo@igalia.com/
Link: https://lore.kernel.org/all/20250418085802.2973519-1-gavinguo@igalia.com/
Fixes: 84c3fc4 ("mm: thp: check pmd migration entry in common path")
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Cc: Florent Revest <revest@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[gavin: backport the migration checking logic to __split_huge_pmd]
Signed-off-by: Gavin Guo <gavinguo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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