From 9870dc39dc53c0ab0534e1d8311a4abed7db570e Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Tue, 18 Jun 2019 10:13:43 +0200 Subject: [PATCH 1/2] drm/panfrost: Make sure a BO is only unmapped when appropriate mmu_ops->unmap() will fail when called on a BO that has not been previously mapped, and the error path in panfrost_ioctl_create_bo() can call drm_gem_object_put_unlocked() (which in turn calls panfrost_mmu_unmap()) on a BO that has not been mapped yet. Keep track of the mapped/unmapped state to avoid such issues. Fixes: f3ba91228e8e ("drm/panfrost: Add initial panfrost driver") Cc: Signed-off-by: Boris Brezillon Signed-off-by: Rob Herring Link: https://patchwork.freedesktop.org/patch/msgid/20190618081343.16927-1-boris.brezillon@collabora.com --- drivers/gpu/drm/panfrost/panfrost_gem.c | 3 ++- drivers/gpu/drm/panfrost/panfrost_gem.h | 1 + drivers/gpu/drm/panfrost/panfrost_mmu.c | 8 ++++++++ 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c b/drivers/gpu/drm/panfrost/panfrost_gem.c index a5528a360ef4f..97d64ceedbb4c 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem.c +++ b/drivers/gpu/drm/panfrost/panfrost_gem.c @@ -19,7 +19,8 @@ static void panfrost_gem_free_object(struct drm_gem_object *obj) struct panfrost_gem_object *bo = to_panfrost_bo(obj); struct panfrost_device *pfdev = obj->dev->dev_private; - panfrost_mmu_unmap(bo); + if (bo->is_mapped) + panfrost_mmu_unmap(bo); spin_lock(&pfdev->mm_lock); drm_mm_remove_node(&bo->node); diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.h b/drivers/gpu/drm/panfrost/panfrost_gem.h index 045000eb5fcfd..6dbcaba020fcb 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem.h +++ b/drivers/gpu/drm/panfrost/panfrost_gem.h @@ -11,6 +11,7 @@ struct panfrost_gem_object { struct drm_gem_shmem_object base; struct drm_mm_node node; + bool is_mapped; }; static inline diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 762b1bd2a8c22..92ac995dd9c66 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -156,6 +156,9 @@ int panfrost_mmu_map(struct panfrost_gem_object *bo) struct sg_table *sgt; int ret; + if (WARN_ON(bo->is_mapped)) + return 0; + sgt = drm_gem_shmem_get_pages_sgt(obj); if (WARN_ON(IS_ERR(sgt))) return PTR_ERR(sgt); @@ -189,6 +192,7 @@ int panfrost_mmu_map(struct panfrost_gem_object *bo) pm_runtime_mark_last_busy(pfdev->dev); pm_runtime_put_autosuspend(pfdev->dev); + bo->is_mapped = true; return 0; } @@ -203,6 +207,9 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) size_t unmapped_len = 0; int ret; + if (WARN_ON(!bo->is_mapped)) + return; + dev_dbg(pfdev->dev, "unmap: iova=%llx, len=%zx", iova, len); ret = pm_runtime_get_sync(pfdev->dev); @@ -230,6 +237,7 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) pm_runtime_mark_last_busy(pfdev->dev); pm_runtime_put_autosuspend(pfdev->dev); + bo->is_mapped = false; } static void mmu_tlb_inv_context_s1(void *cookie) From 74b67efa8d7b4f90137f0ab9a80dd319da050350 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 18 Jun 2019 16:18:43 +0300 Subject: [PATCH 2/2] drm: return -EFAULT if copy_to_user() fails The copy_from_user() function returns the number of bytes remaining to be copied but we want to return a negative error code. Otherwise the callers treat it as a successful copy. Signed-off-by: Dan Carpenter Signed-off-by: Sean Paul Link: https://patchwork.freedesktop.org/patch/msgid/20190618131843.GA29463@mwanda --- drivers/gpu/drm/drm_bufs.c | 5 ++++- drivers/gpu/drm/drm_ioc32.c | 5 ++++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_bufs.c b/drivers/gpu/drm/drm_bufs.c index bfc419ed9d6c5..ceca79b1468d8 100644 --- a/drivers/gpu/drm/drm_bufs.c +++ b/drivers/gpu/drm/drm_bufs.c @@ -1340,7 +1340,10 @@ static int copy_one_buf(void *data, int count, struct drm_buf_entry *from) .size = from->buf_size, .low_mark = from->low_mark, .high_mark = from->high_mark}; - return copy_to_user(to, &v, offsetof(struct drm_buf_desc, flags)); + + if (copy_to_user(to, &v, offsetof(struct drm_buf_desc, flags))) + return -EFAULT; + return 0; } int drm_legacy_infobufs(struct drm_device *dev, void *data, diff --git a/drivers/gpu/drm/drm_ioc32.c b/drivers/gpu/drm/drm_ioc32.c index 374b372da58a4..3972ebe48463d 100644 --- a/drivers/gpu/drm/drm_ioc32.c +++ b/drivers/gpu/drm/drm_ioc32.c @@ -375,7 +375,10 @@ static int copy_one_buf32(void *data, int count, struct drm_buf_entry *from) .size = from->buf_size, .low_mark = from->low_mark, .high_mark = from->high_mark}; - return copy_to_user(to + count, &v, offsetof(drm_buf_desc32_t, flags)); + + if (copy_to_user(to + count, &v, offsetof(drm_buf_desc32_t, flags))) + return -EFAULT; + return 0; } static int drm_legacy_infobufs32(struct drm_device *dev, void *data,