From a5d2ee08adc1d98647679c4e4c73223464d5d936 Mon Sep 17 00:00:00 2001 From: Fedor Pchelkin Date: Wed, 18 Dec 2024 00:19:59 +0300 Subject: [PATCH] Bluetooth: L2CAP: handle NULL sock pointer in l2cap_sock_alloc A NULL sock pointer is passed into l2cap_sock_alloc() when it is called from l2cap_sock_new_connection_cb() and the error handling paths should also be aware of it. Seemingly a more elegant solution would be to swap bt_sock_alloc() and l2cap_chan_create() calls since they are not interdependent to that moment but then l2cap_chan_create() adds the soon to be deallocated and still dummy-initialized channel to the global list accessible by many L2CAP paths. The channel would be removed from the list in short period of time but be a bit more straight-forward here and just check for NULL instead of changing the order of function calls. Found by Linux Verification Center (linuxtesting.org) with SVACE static analysis tool. Fixes: 7c4f78cdb8e7 ("Bluetooth: L2CAP: do not leave dangling sk pointer on error in l2cap_sock_create()") Cc: stable@vger.kernel.org Signed-off-by: Fedor Pchelkin Reviewed-by: Kuniyuki Iwashima Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/l2cap_sock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index 3d2553dcdb1b..49f97d4138ea 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -1888,7 +1888,8 @@ static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock, chan = l2cap_chan_create(); if (!chan) { sk_free(sk); - sock->sk = NULL; + if (sock) + sock->sk = NULL; return NULL; }