Given the following code containing errors, provide Common Weakness Enumeration (CWE) identifiers and corresponding messages in JSON format. Each identified weakness should have a unique entry in the JSON array.
    Code: static int recv_msg(struct kiocb *iocb, struct socket *sock,
		    struct msghdr *m, size_t buf_len, int flags)
{
	struct sock *sk = sock->sk;
	struct tipc_port *tport = tipc_sk_port(sk);
	struct sk_buff *buf;
	struct tipc_msg *msg;
	long timeout;
	unsigned int sz;
	u32 err;
	int res;

	/* Catch invalid receive requests */
	if (unlikely(!buf_len))
		return -EINVAL;

	lock_sock(sk);

	if (unlikely(sock->state == SS_UNCONNECTED)) {
		res = -ENOTCONN;
		goto exit;
	}

	/* will be updated in set_orig_addr() if needed */
	m->msg_namelen = 0;

	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
restart:

	/* Look for a message in receive queue; wait if necessary */
	while (skb_queue_empty(&sk->sk_receive_queue)) {
		if (sock->state == SS_DISCONNECTING) {
			res = -ENOTCONN;
			goto exit;
		}
		if (timeout <= 0L) {
			res = timeout ? timeout : -EWOULDBLOCK;
			goto exit;
		}
		release_sock(sk);
		timeout = wait_event_interruptible_timeout(*sk_sleep(sk),
							   tipc_rx_ready(sock),
							   timeout);
		lock_sock(sk);
	}

	/* Look at first message in receive queue */
	buf = skb_peek(&sk->sk_receive_queue);
	msg = buf_msg(buf);
	sz = msg_data_sz(msg);
	err = msg_errcode(msg);

	/* Discard an empty non-errored message & try again */
	if ((!sz) && (!err)) {
		advance_rx_queue(sk);
		goto restart;
	}

	/* Capture sender's address (optional) */
	set_orig_addr(m, msg);

	/* Capture ancillary data (optional) */
	res = anc_data_recv(m, msg, tport);
	if (res)
		goto exit;

	/* Capture message data (if valid) & compute return value (always) */
	if (!err) {
		if (unlikely(buf_len < sz)) {
			sz = buf_len;
			m->msg_flags |= MSG_TRUNC;
		}
		res = skb_copy_datagram_iovec(buf, msg_hdr_sz(msg),
					      m->msg_iov, sz);
		if (res)
			goto exit;
		res = sz;
	} else {
		if ((sock->state == SS_READY) ||
		    ((err == TIPC_CONN_SHUTDOWN) || m->msg_control))
			res = 0;
		else
			res = -ECONNRESET;
	}

	/* Consume received message (optional) */
	if (likely(!(flags & MSG_PEEK))) {
		if ((sock->state != SS_READY) &&
		    (++tport->conn_unacked >= TIPC_FLOW_CONTROL_WIN))
			tipc_acknowledge(tport->ref, tport->conn_unacked);
		advance_rx_queue(sk);
	}
exit:
	release_sock(sk);
	return res;
} ; Sample JSON Format Confermily Expected output: "examples" => "cwe": "xxx"; "message": "xxx"
    
 'cwe': ['CWE-20', 'CWE-269'], 'message': 'net: rework recvmsg handler msg_name and msg_namelen logic

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
	msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>'