sock: propagate __sock_cmsg_send() error

__sock_cmsg_send() might return different error codes, not only -EINVAL.

Fixes: 24025c465f ("ipv4: process socket-level control messages in IPv4")
Fixes: ad1e46a837 ("ipv6: process socket-level control messages in IPv6")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/ip_sockglue.c

@@ -247,8 +247,9 @@ int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc,
 		}
 #endif
 		if (cmsg->cmsg_level == SOL_SOCKET) {
-			if (__sock_cmsg_send(sk, msg, cmsg, &ipc->sockc))
-				return -EINVAL;
+			err = __sock_cmsg_send(sk, msg, cmsg, &ipc->sockc);
+			if (err)
+				return err;
 			continue;
 		}