From 46841c7053e6d25fb33e0534ef023833bf03e382 Mon Sep 17 00:00:00 2001
From: Kuniyuki Iwashima <kuniyu@amazon.com>
Date: Fri, 10 Jan 2025 10:47:52 +0900
Subject: [PATCH 1/3] gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().
gtp_newlink() links the gtp device to a list in dev_net(dev).
However, even after the gtp device is moved to another netns,
it stays on the list but should be invisible.
Let's use for_each_netdev_rcu() for netdev traversal in
gtp_genl_dump_pdp().
Note that gtp_dev_list is no longer used under RCU, so list
helpers are converted to the non-RCU variant.
Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Reported-by: Xiao Liang <shaw.leon@gmail.com>
Closes: https://lore.kernel.org/netdev/CABAhCOQdBL6h9M2C+kd+bGivRJ9Q72JUxW+-gur0nub_=PmFPA@mail.gmail.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
drivers/net/gtp.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 89a996ad8cd01..0f9cb0c378af5 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -1525,7 +1525,7 @@ static int gtp_newlink(struct net *src_net, struct net_device *dev,
}
gn = net_generic(dev_net(dev), gtp_net_id);
- list_add_rcu(>p->list, &gn->gtp_dev_list);
+ list_add(>p->list, &gn->gtp_dev_list);
dev->priv_destructor = gtp_destructor;
netdev_dbg(dev, "registered new GTP interface\n");
@@ -1551,7 +1551,7 @@ static void gtp_dellink(struct net_device *dev, struct list_head *head)
hlist_for_each_entry_safe(pctx, next, >p->tid_hash[i], hlist_tid)
pdp_context_delete(pctx);
- list_del_rcu(>p->list);
+ list_del(>p->list);
unregister_netdevice_queue(dev, head);
}
@@ -2271,16 +2271,19 @@ static int gtp_genl_dump_pdp(struct sk_buff *skb,
struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
int i, j, bucket = cb->args[0], skip = cb->args[1];
struct net *net = sock_net(skb->sk);
+ struct net_device *dev;
struct pdp_ctx *pctx;
- struct gtp_net *gn;
-
- gn = net_generic(net, gtp_net_id);
if (cb->args[4])
return 0;
rcu_read_lock();
- list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
+ for_each_netdev_rcu(net, dev) {
+ if (dev->rtnl_link_ops != >p_link_ops)
+ continue;
+
+ gtp = netdev_priv(dev);
+
if (last_gtp && last_gtp != gtp)
continue;
else
@@ -2475,9 +2478,9 @@ static void __net_exit gtp_net_exit_batch_rtnl(struct list_head *net_list,
list_for_each_entry(net, net_list, exit_list) {
struct gtp_net *gn = net_generic(net, gtp_net_id);
- struct gtp_dev *gtp;
+ struct gtp_dev *gtp, *gtp_next;
- list_for_each_entry(gtp, &gn->gtp_dev_list, list)
+ list_for_each_entry_safe(gtp, gtp_next, &gn->gtp_dev_list, list)
gtp_dellink(gtp->dev, dev_to_kill);
}
}
From eb28fd76c0a08a47b470677c6cef9dd1c60e92d1 Mon Sep 17 00:00:00 2001
From: Kuniyuki Iwashima <kuniyu@amazon.com>
Date: Fri, 10 Jan 2025 10:47:53 +0900
Subject: [PATCH 2/3] gtp: Destroy device along with udp socket's netns
dismantle.
gtp_newlink() links the device to a list in dev_net(dev) instead of
src_net, where a udp tunnel socket is created.
Even when src_net is removed, the device stays alive on dev_net(dev).
Then, removing src_net triggers the splat below. [0]
In this example, gtp0 is created in ns2, and the udp socket is created
in ns1.
ip netns add ns1
ip netns add ns2
ip -n ns1 link add netns ns2 name gtp0 type gtp role sgsn
ip netns del ns1
Let's link the device to the socket's netns instead.
Now, gtp_net_exit_batch_rtnl() needs another netdev iteration to remove
all gtp devices in the netns.
[0]:
ref_tracker: net notrefcnt@000000003d6e7d05 has 1/2 users at
sk_alloc (./include/net/net_namespace.h:345 net/core/sock.c:2236)
inet_create (net/ipv4/af_inet.c:326 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1558)
udp_sock_create4 (net/ipv4/udp_tunnel_core.c:18)
gtp_create_sock (./include/net/udp_tunnel.h:59 drivers/net/gtp.c:1423)
gtp_create_sockets (drivers/net/gtp.c:1447)
gtp_newlink (drivers/net/gtp.c:1507)
rtnl_newlink (net/core/rtnetlink.c:3786 net/core/rtnetlink.c:3897 net/core/rtnetlink.c:4012)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6922)
netlink_rcv_skb (net/netlink/af_netlink.c:2542)
netlink_unicast (net/netlink/af_netlink.c:1321 net/netlink/af_netlink.c:1347)
netlink_sendmsg (net/netlink/af_netlink.c:1891)
____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2583)
___sys_sendmsg (net/socket.c:2639)
__sys_sendmsg (net/socket.c:2669)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
WARNING: CPU: 1 PID: 60 at lib/ref_tracker.c:179 ref_tracker_dir_exit (lib/ref_tracker.c:179)
Modules linked in:
CPU: 1 UID: 0 PID: 60 Comm: kworker/u16:2 Not tainted 6.13.0-rc5-00147-g4c1224501e9d #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:ref_tracker_dir_exit (lib/ref_tracker.c:179)
Code: 00 00 00 fc ff df 4d 8b 26 49 bd 00 01 00 00 00 00 ad de 4c 39 f5 0f 85 df 00 00 00 48 8b 74 24 08 48 89 df e8 a5 cc 12 02 90 <0f> 0b 90 48 8d 6b 44 be 04 00 00 00 48 89 ef e8 80 de 67 ff 48 89
RSP: 0018:ff11000009a07b60 EFLAGS: 00010286
RAX: 0000000000002bd3 RBX: ff1100000f4e1aa0 RCX: 1ffffffff0e40ac6
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8423ee3c
RBP: ff1100000f4e1af0 R08: 0000000000000001 R09: fffffbfff0e395ae
R10: 0000000000000001 R11: 0000000000036001 R12: ff1100000f4e1af0
R13: dead000000000100 R14: ff1100000f4e1af0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ff1100006ce80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9b2464bd98 CR3: 0000000005286005 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __warn (kernel/panic.c:748)
? ref_tracker_dir_exit (lib/ref_tracker.c:179)
? report_bug (lib/bug.c:201 lib/bug.c:219)
? handle_bug (arch/x86/kernel/traps.c:285)
? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 ./arch/x86/include/asm/irqflags.h:155 ./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194)
? ref_tracker_dir_exit (lib/ref_tracker.c:179)
? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:158)
? kfree (mm/slub.c:4613 mm/slub.c:4761)
net_free (net/core/net_namespace.c:476 net/core/net_namespace.c:467)
cleanup_net (net/core/net_namespace.c:664 (discriminator 3))
process_one_work (kernel/workqueue.c:3229)
worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
kthread (kernel/kthread.c:389)
ret_from_fork (arch/x86/kernel/process.c:147)
ret_from_fork_asm (arch/x86/entry/entry_64.S:257)
</TASK>
Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Reported-by: Xiao Liang <shaw.leon@gmail.com>
Closes: https://lore.kernel.org/netdev/20250104125732.17335-1-shaw.leon@gmail.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
drivers/net/gtp.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 0f9cb0c378af5..fbabada7d3ba9 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -1524,7 +1524,7 @@ static int gtp_newlink(struct net *src_net, struct net_device *dev,
goto out_encap;
}
- gn = net_generic(dev_net(dev), gtp_net_id);
+ gn = net_generic(src_net, gtp_net_id);
list_add(>p->list, &gn->gtp_dev_list);
dev->priv_destructor = gtp_destructor;
@@ -2479,6 +2479,11 @@ static void __net_exit gtp_net_exit_batch_rtnl(struct list_head *net_list,
list_for_each_entry(net, net_list, exit_list) {
struct gtp_net *gn = net_generic(net, gtp_net_id);
struct gtp_dev *gtp, *gtp_next;
+ struct net_device *dev;
+
+ for_each_netdev(net, dev)
+ if (dev->rtnl_link_ops == >p_link_ops)
+ gtp_dellink(dev, dev_to_kill);
list_for_each_entry_safe(gtp, gtp_next, &gn->gtp_dev_list, list)
gtp_dellink(gtp->dev, dev_to_kill);
From ffc90e9ca61b0f619326a1417ff32efd6cc71ed2 Mon Sep 17 00:00:00 2001
From: Kuniyuki Iwashima <kuniyu@amazon.com>
Date: Fri, 10 Jan 2025 10:47:54 +0900
Subject: [PATCH 3/3] pfcp: Destroy device along with udp socket's netns
dismantle.
pfcp_newlink() links the device to a list in dev_net(dev) instead
of net, where a udp tunnel socket is created.
Even when net is removed, the device stays alive on dev_net(dev).
Then, removing net triggers the splat below. [0]
In this example, pfcp0 is created in ns2, but the udp socket is
created in ns1.
ip netns add ns1
ip netns add ns2
ip -n ns1 link add netns ns2 name pfcp0 type pfcp
ip netns del ns1
Let's link the device to the socket's netns instead.
Now, pfcp_net_exit() needs another netdev iteration to remove
all pfcp devices in the netns.
pfcp_dev_list is not used under RCU, so the list API is converted
to the non-RCU variant.
pfcp_net_exit() can be converted to .exit_batch_rtnl() in net-next.
[0]:
ref_tracker: net notrefcnt@00000000128b34dc has 1/1 users at
sk_alloc (./include/net/net_namespace.h:345 net/core/sock.c:2236)
inet_create (net/ipv4/af_inet.c:326 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1558)
udp_sock_create4 (net/ipv4/udp_tunnel_core.c:18)
pfcp_create_sock (drivers/net/pfcp.c:168)
pfcp_newlink (drivers/net/pfcp.c:182 drivers/net/pfcp.c:197)
rtnl_newlink (net/core/rtnetlink.c:3786 net/core/rtnetlink.c:3897 net/core/rtnetlink.c:4012)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6922)
netlink_rcv_skb (net/netlink/af_netlink.c:2542)
netlink_unicast (net/netlink/af_netlink.c:1321 net/netlink/af_netlink.c:1347)
netlink_sendmsg (net/netlink/af_netlink.c:1891)
____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2583)
___sys_sendmsg (net/socket.c:2639)
__sys_sendmsg (net/socket.c:2669)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
WARNING: CPU: 1 PID: 11 at lib/ref_tracker.c:179 ref_tracker_dir_exit (lib/ref_tracker.c:179)
Modules linked in:
CPU: 1 UID: 0 PID: 11 Comm: kworker/u16:0 Not tainted 6.13.0-rc5-00147-g4c1224501e9d #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:ref_tracker_dir_exit (lib/ref_tracker.c:179)
Code: 00 00 00 fc ff df 4d 8b 26 49 bd 00 01 00 00 00 00 ad de 4c 39 f5 0f 85 df 00 00 00 48 8b 74 24 08 48 89 df e8 a5 cc 12 02 90 <0f> 0b 90 48 8d 6b 44 be 04 00 00 00 48 89 ef e8 80 de 67 ff 48 89
RSP: 0018:ff11000007f3fb60 EFLAGS: 00010286
RAX: 00000000000020ef RBX: ff1100000d6481e0 RCX: 1ffffffff0e40d82
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8423ee3c
RBP: ff1100000d648230 R08: 0000000000000001 R09: fffffbfff0e395af
R10: 0000000000000001 R11: 0000000000000000 R12: ff1100000d648230
R13: dead000000000100 R14: ff1100000d648230 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ff1100006ce80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005620e1363990 CR3: 000000000eeb2002 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __warn (kernel/panic.c:748)
? ref_tracker_dir_exit (lib/ref_tracker.c:179)
? report_bug (lib/bug.c:201 lib/bug.c:219)
? handle_bug (arch/x86/kernel/traps.c:285)
? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 ./arch/x86/include/asm/irqflags.h:155 ./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194)
? ref_tracker_dir_exit (lib/ref_tracker.c:179)
? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:158)
? kfree (mm/slub.c:4613 mm/slub.c:4761)
net_free (net/core/net_namespace.c:476 net/core/net_namespace.c:467)
cleanup_net (net/core/net_namespace.c:664 (discriminator 3))
process_one_work (kernel/workqueue.c:3229)
worker_thread (kernel/workqueue.c:3304 kernel/workqueue.c:3391)
kthread (kernel/kthread.c:389)
ret_from_fork (arch/x86/kernel/process.c:147)
ret_from_fork_asm (arch/x86/entry/entry_64.S:257)
</TASK>
Fixes: 76c8764ef36a ("pfcp: add PFCP module")
Reported-by: Xiao Liang <shaw.leon@gmail.com>
Closes: https://lore.kernel.org/netdev/20250104125732.17335-1-shaw.leon@gmail.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
drivers/net/pfcp.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/net/pfcp.c b/drivers/net/pfcp.c
index 69434fd13f961..68d0d9e92a220 100644
--- a/drivers/net/pfcp.c
+++ b/drivers/net/pfcp.c
@@ -206,8 +206,8 @@ static int pfcp_newlink(struct net *net, struct net_device *dev,
goto exit_del_pfcp_sock;
}
- pn = net_generic(dev_net(dev), pfcp_net_id);
- list_add_rcu(&pfcp->list, &pn->pfcp_dev_list);
+ pn = net_generic(net, pfcp_net_id);
+ list_add(&pfcp->list, &pn->pfcp_dev_list);
netdev_dbg(dev, "registered new PFCP interface\n");
@@ -224,7 +224,7 @@ static void pfcp_dellink(struct net_device *dev, struct list_head *head)
{
struct pfcp_dev *pfcp = netdev_priv(dev);
- list_del_rcu(&pfcp->list);
+ list_del(&pfcp->list);
unregister_netdevice_queue(dev, head);
}
@@ -247,11 +247,16 @@ static int __net_init pfcp_net_init(struct net *net)
static void __net_exit pfcp_net_exit(struct net *net)
{
struct pfcp_net *pn = net_generic(net, pfcp_net_id);
- struct pfcp_dev *pfcp;
+ struct pfcp_dev *pfcp, *pfcp_next;
+ struct net_device *dev;
LIST_HEAD(list);
rtnl_lock();
- list_for_each_entry(pfcp, &pn->pfcp_dev_list, list)
+ for_each_netdev(net, dev)
+ if (dev->rtnl_link_ops == &pfcp_link_ops)
+ pfcp_dellink(dev, &list);
+
+ list_for_each_entry_safe(pfcp, pfcp_next, &pn->pfcp_dev_list, list)
pfcp_dellink(pfcp->dev, &list);
unregister_netdevice_many(&list);