net: ieee802154: do not leave a dangling sk pointer in ieee802154_create()

sock_init_data() attaches the allocated sk object to the provided sock
object. If ieee802154_create() fails later, the allocated sk object is
freed, but the dangling pointer remains in the provided sock object, which
may allow use-after-free.

Clear the sk pointer in the sock object on error.

Signed-off-by: Ignat Korchagin <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Reviewed-by: Kuniyuki Iwashima <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: ignatk

net/ieee802154/socket.c

@@ -1043,19 +1043,21 @@ static int ieee802154_create(struct net *net, struct socket *sock,
 
 	if (sk->sk_prot->hash) {
 		rc = sk->sk_prot->hash(sk);
-		if (rc) {
-			sk_common_release(sk);
-			goto out;
-		}
+		if (rc)
+			goto out_sk_release;
 	}
 
 	if (sk->sk_prot->init) {
 		rc = sk->sk_prot->init(sk);
 		if (rc)
-			sk_common_release(sk);
+			goto out_sk_release;
 	}
 out:
 	return rc;
+out_sk_release:
+	sk_common_release(sk);
+	sock->sk = NULL;
+	goto out;
 }
 
 static const struct net_proto_family ieee802154_family_ops = {