diff mbox series

[net-next,v3,4/9] net: af_can: do not leave a dangling sk pointer in can_create()

Message ID 20241014153808.51894-5-ignat@cloudflare.com
State Accepted
Commit 811a7ca7320c062e15d0f5b171fe6ad8592d1434
Headers show
Series do not leave dangling sk pointers in pf->create functions | expand

Commit Message

Ignat Korchagin Oct. 14, 2024, 3:38 p.m. UTC 
On error can_create() frees the allocated sk object, but sock_init_data()
has already attached it to the provided sock object. This will leave a
dangling sk pointer in the sock object and may cause use-after-free later.

Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
---
 net/can/af_can.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Kuniyuki Iwashima Oct. 14, 2024, 9:32 p.m. UTC | #1 
From: Ignat Korchagin <ignat@cloudflare.com>
Date: Mon, 14 Oct 2024 16:38:03 +0100
> On error can_create() frees the allocated sk object, but sock_init_data()
> has already attached it to the provided sock object. This will leave a
> dangling sk pointer in the sock object and may cause use-after-free later.
> 
> Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
> Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Marc Kleine-Budde Oct. 15, 2024, 6:21 a.m. UTC | #2 
On 14.10.2024 16:38:03, Ignat Korchagin wrote:
> On error can_create() frees the allocated sk object, but sock_init_data()
> has already attached it to the provided sock object. This will leave a
> dangling sk pointer in the sock object and may cause use-after-free later.
> 
> Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
> Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>

Reviewed-by: Marc Kleine-Budde <mkl@pengutronix.de>

regards,
Marc
diff mbox series

Patch

diff --git a/net/can/af_can.c b/net/can/af_can.c
index 707576eeeb58..01f3fbb3b67d 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -171,6 +171,7 @@  static int can_create(struct net *net, struct socket *sock, int protocol,
 		/* release sk on errors */
 		sock_orphan(sk);
 		sock_put(sk);
+		sock->sk = NULL;
 	}
 
  errout: