From: Fedor Pchelkin <pchelkin@ispras.ru> maillist inclusion category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBEANO CVE: CVE-2024-56605 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git... ---------------------------------------- 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 <pchelkin@ispras.ru> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Lin Ruifeng <linruifeng4@huawei.com> --- 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 9f4a4391f6fe..05fea988b4cf 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -1629,7 +1629,8 @@ 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; } -- 2.22.0