Patch "tcp: Fix listen() regression in 5.15.88." has been added to the 5.15-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    tcp: Fix listen() regression in 5.15.88.

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     tcp-fix-listen-regression-in-5.15.88.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


From kuniyu@amazon.com  Fri Feb 17 15:21:48 2023
From: Kuniyuki Iwashima <kuniyu@amazon.com>
Date: Mon, 13 Feb 2023 20:45:48 +0000
Subject: tcp: Fix listen() regression in 5.15.88.
To: <gregkh@linuxfoundation.org>
Cc: <kuniyu@amazon.com>, <netdev@vger.kernel.org>, <regressions@lists.linux.dev>, <stable@vger.kernel.org>, <w@1wt.eu>, <winter@winter.cafe>
Message-ID: <20230213205835.56151-1-kuniyu@amazon.com>

From: Kuniyuki Iwashima <kuniyu@amazon.com>

When we backport dadd0dcaa67d ("net/ulp: prevent ULP without clone op from
entering the LISTEN status"), we have accidentally backported a part of
7a7160edf1bf ("net: Return errno in sk->sk_prot->get_port().") and removed
err = -EADDRINUSE in inet_csk_listen_start().

Thus, listen() no longer returns -EADDRINUSE even if ->get_port() failed
as reported in [0].

We set -EADDRINUSE to err just before ->get_port() to fix the regression.

[0]: https://lore.kernel.org/stable/EF8A45D0-768A-4CD5-9A8A-0FA6E610ABF7@winter.cafe/

Reported-by: Winter <winter@winter.cafe>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/inet_connection_sock.c |    1 +
 1 file changed, 1 insertion(+)

--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -1070,6 +1070,7 @@ int inet_csk_listen_start(struct sock *s
 	 * It is OK, because this socket enters to hash table only
 	 * after validation is complete.
 	 */
+	err = -EADDRINUSE;
 	inet_sk_state_store(sk, TCP_LISTEN);
 	if (!sk->sk_prot->get_port(sk, inet->inet_num)) {
 		inet->inet_sport = htons(inet->inet_num);


Patches currently in stable-queue which might be from kuniyu@amazon.com are

queue-5.15/net-rose-fix-to-not-accept-on-connected-socket.patch
queue-5.15/tcp-fix-listen-regression-in-5.15.88.patch