Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933989AbbFSVU6 (ORCPT ); Fri, 19 Jun 2015 17:20:58 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:51461 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756027AbbFSUjA (ORCPT ); Fri, 19 Jun 2015 16:39:00 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Herbert Xu Subject: [PATCH 4.0 029/105] netlink: Disable insertions/removals during rehash Date: Fri, 19 Jun 2015 13:35:19 -0700 Message-Id: <20150619203559.070279559@linuxfoundation.org> X-Mailer: git-send-email 2.4.4 In-Reply-To: <20150619203558.187802739@linuxfoundation.org> References: <20150619203558.187802739@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1620 Lines: 59 4.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Herbert Xu [ Upstream commit: Not applicable ] The current rhashtable rehash code is buggy and can't deal with parallel insertions/removals without corrupting the hash table. This patch disables it by partially reverting c5adde9468b0714a051eac7f9666f23eb10b61f7 ("netlink: eliminate nl_sk_hash_lock"). Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- net/netlink/af_netlink.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1052,7 +1052,7 @@ static int netlink_insert(struct sock *s struct netlink_table *table = &nl_table[sk->sk_protocol]; int err; - lock_sock(sk); + mutex_lock(&table->hash.mutex); err = -EBUSY; if (nlk_sk(sk)->portid) @@ -1074,7 +1074,7 @@ static int netlink_insert(struct sock *s } err: - release_sock(sk); + mutex_unlock(&table->hash.mutex); return err; } @@ -1083,10 +1083,12 @@ static void netlink_remove(struct sock * struct netlink_table *table; table = &nl_table[sk->sk_protocol]; + mutex_lock(&table->hash.mutex); if (rhashtable_remove(&table->hash, &nlk_sk(sk)->node)) { WARN_ON(atomic_read(&sk->sk_refcnt) == 1); __sock_put(sk); } + mutex_unlock(&table->hash.mutex); netlink_table_grab(); if (nlk_sk(sk)->subscriptions) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in Please read the FAQ at http://www.tux.org/lkml/