sock: unlock on error in sock_setsockopt()

If copy_from_sockptr() then we need to unlock before returning.

Fixes: d463126e ("net: sock: extend SO_TIMESTAMPING for PHC binding")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/sock.c

@@ -1123,8 +1123,10 @@ int sock_setsockopt(struct socket *sock, int level, int optname,
 	case SO_TIMESTAMPING_OLD:
 		if (optlen == sizeof(timestamping)) {
 			if (copy_from_sockptr(&timestamping, optval,
-					      sizeof(timestamping)))
-				return -EFAULT;
+					      sizeof(timestamping))) {
+				ret = -EFAULT;
+				break;
+			}
 		} else {
 			memset(&timestamping, 0, sizeof(timestamping));
 			timestamping.flags = val;