* [PATCH net-next] mptcp: adjust to use netns refcount tracker
@ 2021-12-14 4:32 Eric Dumazet
2021-12-14 8:57 ` Paolo Abeni
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Eric Dumazet @ 2021-12-14 4:32 UTC (permalink / raw)
To: David S . Miller, Jakub Kicinski
Cc: netdev, Eric Dumazet, Eric Dumazet, syzbot, Mat Martineau,
Matthieu Baerts, Florian Westphal, Paolo Abeni
From: Eric Dumazet <edumazet@google.com>
MPTCP can change sk_net_refcnt after sock_create_kern() call.
We need to change its corresponding get_net() to avoid
a splat at release time, as in :
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 3599 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Modules linked in:
CPU: 1 PID: 3599 Comm: syz-fuzzer Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Code: 1d b1 99 a1 09 31 ff 89 de e8 5d 3a 9c fd 84 db 75 e0 e8 74 36 9c fd 48 c7 c7 60 00 05 8a c6 05 91 99 a1 09 01 e8 cc 4b 27 05 <0f> 0b eb c4 e8 58 36 9c fd 0f b6 1d 80 99 a1 09 31 ff 89 de e8 28
RSP: 0018:ffffc90001f5fab0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888021873a00 RSI: ffffffff815f1e28 RDI: fffff520003ebf48
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815ebbce R11: 0000000000000000 R12: 1ffff920003ebf5b
R13: 00000000ffffffef R14: ffffffff8d2fcd94 R15: ffffc90001f5fd10
FS: 000000c00008a090(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0a5b59e300 CR3: 000000001cbe6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__refcount_dec include/linux/refcount.h:344 [inline]
refcount_dec include/linux/refcount.h:359 [inline]
ref_tracker_free+0x4fe/0x610 lib/ref_tracker.c:101
netns_tracker_free include/net/net_namespace.h:327 [inline]
put_net_track include/net/net_namespace.h:341 [inline]
__sk_destruct+0x4a6/0x920 net/core/sock.c:2042
sk_destruct+0xbd/0xe0 net/core/sock.c:2058
__sk_free+0xef/0x3d0 net/core/sock.c:2069
sk_free+0x78/0xa0 net/core/sock.c:2080
sock_put include/net/sock.h:1911 [inline]
__mptcp_close_ssk+0x435/0x590 net/mptcp/protocol.c:2276
__mptcp_destroy_sock+0x35f/0x830 net/mptcp/protocol.c:2702
mptcp_close+0x5f8/0x7f0 net/mptcp/protocol.c:2750
inet_release+0x12e/0x280 net/ipv4/af_inet.c:428
inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:476
__sock_release+0xcd/0x280 net/socket.c:649
sock_close+0x18/0x20 net/socket.c:1314
__fput+0x286/0x9f0 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
Fixes: ffa84b5ffb37 ("net: add netns refcount tracker to struct sock")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Mat Martineau <mathew.j.martineau@linux.intel.com>
Cc: Matthieu Baerts <matthieu.baerts@tessares.net>
Cc: Florian Westphal <fw@strlen.de>
Cc: Paolo Abeni <pabeni@redhat.com>
---
net/mptcp/subflow.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index b8dd3441f7d00357dfac6121f6288b9300ea5201..24bc9d5e87be44542f5094cda39dcc59f8f9f10d 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -1534,7 +1534,7 @@ int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock)
* needs it.
*/
sf->sk->sk_net_refcnt = 1;
- get_net(net);
+ get_net_track(net, &sf->sk->ns_tracker, GFP_KERNEL);
sock_inuse_add(net, 1);
err = tcp_set_ulp(sf->sk, "mptcp");
release_sock(sf->sk);
--
2.34.1.173.g76aa8bc2d0-goog
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH net-next] mptcp: adjust to use netns refcount tracker
2021-12-14 4:32 [PATCH net-next] mptcp: adjust to use netns refcount tracker Eric Dumazet
@ 2021-12-14 8:57 ` Paolo Abeni
2021-12-14 9:32 ` Matthieu Baerts
2021-12-15 3:00 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: Paolo Abeni @ 2021-12-14 8:57 UTC (permalink / raw)
To: Eric Dumazet, David S . Miller, Jakub Kicinski
Cc: netdev, Eric Dumazet, syzbot, Mat Martineau, Matthieu Baerts,
Florian Westphal
On Mon, 2021-12-13 at 20:32 -0800, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
>
> MPTCP can change sk_net_refcnt after sock_create_kern() call.
>
> We need to change its corresponding get_net() to avoid
> a splat at release time, as in :
>
> refcount_t: decrement hit 0; leaking memory.
> WARNING: CPU: 0 PID: 3599 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
> Modules linked in:
> CPU: 1 PID: 3599 Comm: syz-fuzzer Not tainted 5.16.0-rc4-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
> Code: 1d b1 99 a1 09 31 ff 89 de e8 5d 3a 9c fd 84 db 75 e0 e8 74 36 9c fd 48 c7 c7 60 00 05 8a c6 05 91 99 a1 09 01 e8 cc 4b 27 05 <0f> 0b eb c4 e8 58 36 9c fd 0f b6 1d 80 99 a1 09 31 ff 89 de e8 28
> RSP: 0018:ffffc90001f5fab0 EFLAGS: 00010286
> RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
> RDX: ffff888021873a00 RSI: ffffffff815f1e28 RDI: fffff520003ebf48
> RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
> R10: ffffffff815ebbce R11: 0000000000000000 R12: 1ffff920003ebf5b
> R13: 00000000ffffffef R14: ffffffff8d2fcd94 R15: ffffc90001f5fd10
> FS: 000000c00008a090(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f0a5b59e300 CR3: 000000001cbe6000 CR4: 00000000003506e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <TASK>
> __refcount_dec include/linux/refcount.h:344 [inline]
> refcount_dec include/linux/refcount.h:359 [inline]
> ref_tracker_free+0x4fe/0x610 lib/ref_tracker.c:101
> netns_tracker_free include/net/net_namespace.h:327 [inline]
> put_net_track include/net/net_namespace.h:341 [inline]
> __sk_destruct+0x4a6/0x920 net/core/sock.c:2042
> sk_destruct+0xbd/0xe0 net/core/sock.c:2058
> __sk_free+0xef/0x3d0 net/core/sock.c:2069
> sk_free+0x78/0xa0 net/core/sock.c:2080
> sock_put include/net/sock.h:1911 [inline]
> __mptcp_close_ssk+0x435/0x590 net/mptcp/protocol.c:2276
> __mptcp_destroy_sock+0x35f/0x830 net/mptcp/protocol.c:2702
> mptcp_close+0x5f8/0x7f0 net/mptcp/protocol.c:2750
> inet_release+0x12e/0x280 net/ipv4/af_inet.c:428
> inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:476
> __sock_release+0xcd/0x280 net/socket.c:649
> sock_close+0x18/0x20 net/socket.c:1314
> __fput+0x286/0x9f0 fs/file_table.c:280
> task_work_run+0xdd/0x1a0 kernel/task_work.c:164
> tracehook_notify_resume include/linux/tracehook.h:189 [inline]
> exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
> exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
> __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
> syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
> do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
> entry_SYSCALL_64_after_hwframe+0x44/0xae
>
> Fixes: ffa84b5ffb37 ("net: add netns refcount tracker to struct sock")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: syzbot <syzkaller@googlegroups.com>
> Cc: Mat Martineau <mathew.j.martineau@linux.intel.com>
> Cc: Matthieu Baerts <matthieu.baerts@tessares.net>
> Cc: Florian Westphal <fw@strlen.de>
> Cc: Paolo Abeni <pabeni@redhat.com>
> ---
> net/mptcp/subflow.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
> index b8dd3441f7d00357dfac6121f6288b9300ea5201..24bc9d5e87be44542f5094cda39dcc59f8f9f10d 100644
> --- a/net/mptcp/subflow.c
> +++ b/net/mptcp/subflow.c
> @@ -1534,7 +1534,7 @@ int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock)
> * needs it.
> */
> sf->sk->sk_net_refcnt = 1;
> - get_net(net);
> + get_net_track(net, &sf->sk->ns_tracker, GFP_KERNEL);
> sock_inuse_add(net, 1);
> err = tcp_set_ulp(sf->sk, "mptcp");
> release_sock(sf->sk);
LGTM, thanks Eric!
(and more thanks for the whole tracking infra!)
Acked-by: Paolo Abeni <pabeni@redhat.com>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH net-next] mptcp: adjust to use netns refcount tracker
2021-12-14 4:32 [PATCH net-next] mptcp: adjust to use netns refcount tracker Eric Dumazet
2021-12-14 8:57 ` Paolo Abeni
@ 2021-12-14 9:32 ` Matthieu Baerts
2021-12-15 3:00 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: Matthieu Baerts @ 2021-12-14 9:32 UTC (permalink / raw)
To: Eric Dumazet, David S . Miller, Jakub Kicinski
Cc: netdev, Eric Dumazet, syzbot, Mat Martineau, Florian Westphal,
Paolo Abeni
Hi Eric,
On 14/12/2021 05:32, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
>
> MPTCP can change sk_net_refcnt after sock_create_kern() call.
Thank you for the fix and the new tracking infra!
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Cheers,
Matt
--
Tessares | Belgium | Hybrid Access Solutions
www.tessares.net
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH net-next] mptcp: adjust to use netns refcount tracker
2021-12-14 4:32 [PATCH net-next] mptcp: adjust to use netns refcount tracker Eric Dumazet
2021-12-14 8:57 ` Paolo Abeni
2021-12-14 9:32 ` Matthieu Baerts
@ 2021-12-15 3:00 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: patchwork-bot+netdevbpf @ 2021-12-15 3:00 UTC (permalink / raw)
To: Eric Dumazet
Cc: davem, kuba, netdev, edumazet, syzkaller, mathew.j.martineau,
matthieu.baerts, fw, pabeni
Hello:
This patch was applied to netdev/net-next.git (master)
by Jakub Kicinski <kuba@kernel.org>:
On Mon, 13 Dec 2021 20:32:08 -0800 you wrote:
> From: Eric Dumazet <edumazet@google.com>
>
> MPTCP can change sk_net_refcnt after sock_create_kern() call.
>
> We need to change its corresponding get_net() to avoid
> a splat at release time, as in :
>
> [...]
Here is the summary with links:
- [net-next] mptcp: adjust to use netns refcount tracker
https://git.kernel.org/netdev/net-next/c/1d2f3d3c6268
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-12-15 3:00 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-12-14 4:32 [PATCH net-next] mptcp: adjust to use netns refcount tracker Eric Dumazet
2021-12-14 8:57 ` Paolo Abeni
2021-12-14 9:32 ` Matthieu Baerts
2021-12-15 3:00 ` patchwork-bot+netdevbpf
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.