net: streamline __sys_getsockopt

Return early when sockfd_lookup_light fails to reduce a level of
indentation for most of the function body.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/socket.c

@@ -2163,28 +2163,25 @@ static int __sys_getsockopt(int fd, int level, int optname,
 	int max_optlen;
 
 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
-	if (sock != NULL) {
-		err = security_socket_getsockopt(sock, level, optname);
-		if (err)
-			goto out_put;
+	if (!sock)
+		return err;
 
-		max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
+	err = security_socket_getsockopt(sock, level, optname);
+	if (err)
+		goto out_put;
 
-		if (level == SOL_SOCKET)
-			err =
-			    sock_getsockopt(sock, level, optname, optval,
+	max_optlen = BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen);
+
+	if (level == SOL_SOCKET)
+		err = sock_getsockopt(sock, level, optname, optval, optlen);
+	else
+		err = sock->ops->getsockopt(sock, level, optname, optval,
 					    optlen);
-		else
-			err =
-			    sock->ops->getsockopt(sock, level, optname, optval,
-						  optlen);
 
-		err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname,
-						     optval, optlen,
-						     max_optlen, err);
+	err = BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock->sk, level, optname, optval,
+					     optlen, max_optlen, err);
 out_put:
-		fput_light(sock->file, fput_needed);
-	}
+	fput_light(sock->file, fput_needed);
 	return err;
 }