diff mbox series

[net-next,v3,8/9] net: warn, if pf->create does not clear sock->sk on error

Message ID 20241014153808.51894-9-ignat@cloudflare.com (mailing list archive)
State Accepted
Commit 48156296a08c615a6baae514096c4b2e543d1157
Headers show
Series do not leave dangling sk pointers in pf->create functions | expand

Checks

Context Check Description
tedd_an/pre-ci_am fail error: patch failed: net/socket.c:1576 error: net/socket.c: patch does not apply hint: Use 'git am --show-current-patch' to see the failed patch

Commit Message

Ignat Korchagin Oct. 14, 2024, 3:38 p.m. UTC
All pf->create implementations have been fixed now to clear sock->sk on
error, when they deallocate the allocated sk object.

Put a warning in place to make sure we don't break this promise in the
future.

Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
---
 net/socket.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Kuniyuki Iwashima Oct. 14, 2024, 9:40 p.m. UTC | #1
From: Ignat Korchagin <ignat@cloudflare.com>
Date: Mon, 14 Oct 2024 16:38:07 +0100
> All pf->create implementations have been fixed now to clear sock->sk on
> error, when they deallocate the allocated sk object.
> 
> Put a warning in place to make sure we don't break this promise in the
> future.
> 
> Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
> Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Eric Dumazet Oct. 15, 2024, 8:06 a.m. UTC | #2
On Mon, Oct 14, 2024 at 11:40 PM Kuniyuki Iwashima <kuniyu@amazon.com> wrote:
>
> From: Ignat Korchagin <ignat@cloudflare.com>
> Date: Mon, 14 Oct 2024 16:38:07 +0100
> > All pf->create implementations have been fixed now to clear sock->sk on
> > error, when they deallocate the allocated sk object.
> >
> > Put a warning in place to make sure we don't break this promise in the
> > future.
> >
> > Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
> > Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
>
> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>

Reviewed-by: Eric Dumazet <edumazet@google.com>
diff mbox series

Patch

diff --git a/net/socket.c b/net/socket.c
index 24b404299015..9a8e4452b9b2 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1576,9 +1576,9 @@  int __sock_create(struct net *net, int family, int type, int protocol,
 	err = pf->create(net, sock, protocol, kern);
 	if (err < 0) {
 		/* ->create should release the allocated sock->sk object on error
-		 * but it may leave the dangling pointer
+		 * and make sure sock->sk is set to NULL to avoid use-after-free
 		 */
-		sock->sk = NULL;
+		DEBUG_NET_WARN_ON_ONCE(sock->sk);
 		goto out_module_put;
 	}