netdev - [PATCH] net: tcp: deal with listen sockets properly in tcp

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 22 Dec 2015 00:03:44 +0900
From:	Lorenzo Colitti <lorenzo@...gle.com>
To:	netdev@...r.kernel.org
Cc:	davem@...emloft.net, eric.dumazet@...il.com, tom@...bertland.com,
	Lorenzo Colitti <lorenzo@...gle.com>
Subject: [PATCH] net: tcp: deal with listen sockets properly in tcp_abort.

When closing a listen socket, tcp_abort currently calls
tcp_done without clearing the request queue. If the socket has a
child socket that is established but not yet accepted, the child
socket is then left without a parent, causing a leak.

Fix this by setting the socket state to TCP_CLOSE and calling
inet_csk_listen_stop with the socket lock held, like tcp_close
does.

Tested using net_test. With this patch, calling SOCK_DESTROY on a
listen socket that has an established but not yet accepted child
socket results in the parent and the child being closed, such
that they no longer appear in sock_diag dumps.

Reported-by: Eric Dumazet <eric.dumazet@...il.com>
Signed-off-by: Lorenzo Colitti <lorenzo@...gle.com>
---
 net/ipv4/tcp.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index cc7aaa5..7bb1b09 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3099,6 +3099,11 @@ int tcp_abort(struct sock *sk, int err)
 	/* Don't race with userspace socket closes such as tcp_close. */
 	lock_sock(sk);

+	if (sk->sk_state == TCP_LISTEN) {
+		tcp_set_state(sk, TCP_CLOSE);
+		inet_csk_listen_stop(sk);
+	}
+
 	/* Don't race with BH socket closes such as inet_csk_listen_stop. */
 	local_bh_disable();
 	bh_lock_sock(sk);
-- 
2.6.0.rc2.230.g3dd15c0

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html