netdev - [PATCH 2/2] tcp: bind() optimize port allocation

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

Date:	Wed, 25 Jan 2012 16:34:52 -0200
From:	Flavio Leitner <fbl@...hat.com>
To:	netdev <netdev@...r.kernel.org>
Cc:	Marcelo Leitner <mleitner@...hat.com>,
	Eric Dumazet <eric.dumazet@...il.com>,
	Flavio Leitner <fbl@...hat.com>
Subject: [PATCH 2/2] tcp: bind() optimize port allocation

Port autoselection finds a port and then drop the lock,
then right after that, gets the hash bucket again and lock it.

Fix it to go direct.

Signed-off-by: Flavio Leitner <fbl@...hat.com>
---
 net/ipv4/inet_connection_sock.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index ecd19b5..19d66ce 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -123,15 +123,13 @@ again:
 						smallest_size = tb->num_owners;
 						smallest_rover = rover;
 						if (atomic_read(&hashinfo->bsockets) > (high - low) + 1) {
-							spin_unlock(&head->lock);
 							snum = smallest_rover;
-							goto have_snum;
+							goto tb_found;
 						}
 					}
 					if (!inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
-						spin_unlock(&head->lock);
 						snum = rover;
-						goto have_snum;
+						goto tb_found;
 					}
 					goto next;
 				}
-- 
1.7.7.1

--
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