[PATCH v2 3/8] Bluetooth: L2CAP: do not leave dangling sk pointer on error in l2cap_sock_create()

From: Ignat Korchagin
Date: Mon Oct 07 2024 - 17:36:53 EST


bt_sock_alloc() allocates the sk object and attaches it to the provided
sock object. On error l2cap_sock_alloc() frees the sk object, but the
dangling pointer is still attached to the sock object, which may create
use-after-free in other code.

Signed-off-by: Ignat Korchagin <ignat@xxxxxxxxxxxxxx>
---
net/bluetooth/l2cap_sock.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index ba437c6f6ee5..18e89e764f3b 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -1886,6 +1886,7 @@ static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
chan = l2cap_chan_create();
if (!chan) {
sk_free(sk);
+ sock->sk = NULL;
return NULL;
}

--
2.39.5