Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758160Ab2KVWHz (ORCPT ); Thu, 22 Nov 2012 17:07:55 -0500 Received: from mail.kernel.org ([198.145.19.201]:49604 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754839Ab2KVSkH (ORCPT ); Thu, 22 Nov 2012 13:40:07 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Dave Jones , "Paul E. McKenney" , Paul Moore , Eric Paris , Andrew Morton , James Morris Subject: [ 055/171] selinux: fix sel_netnode_insert() suspicious rcu dereference Date: Wed, 21 Nov 2012 16:40:01 -0800 Message-Id: <20121122004038.889596180@linuxfoundation.org> X-Mailer: git-send-email 1.8.0.197.g5a90748 In-Reply-To: <20121122004033.298367941@linuxfoundation.org> References: <20121122004033.298367941@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2653 Lines: 70 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dave Jones commit 88a693b5c1287be4da937699cb82068ce9db0135 upstream. =============================== [ INFO: suspicious RCU usage. ] 3.5.0-rc1+ #63 Not tainted ------------------------------- security/selinux/netnode.c:178 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by trinity-child1/8750: #0: (sel_netnode_lock){+.....}, at: [] sel_netnode_sid+0x16a/0x3e0 stack backtrace: Pid: 8750, comm: trinity-child1 Not tainted 3.5.0-rc1+ #63 Call Trace: [] lockdep_rcu_suspicious+0xfd/0x130 [] sel_netnode_sid+0x3b1/0x3e0 [] ? sel_netnode_find+0x1a0/0x1a0 [] selinux_socket_bind+0xf6/0x2c0 [] ? trace_hardirqs_off+0xd/0x10 [] ? lock_release_holdtime.part.9+0x15/0x1a0 [] ? lock_hrtimer_base+0x31/0x60 [] security_socket_bind+0x16/0x20 [] sys_bind+0x7a/0x100 [] ? sysret_check+0x22/0x5d [] ? trace_hardirqs_on_caller+0x10d/0x1a0 [] ? trace_hardirqs_on_thunk+0x3a/0x3f [] system_call_fastpath+0x16/0x1b This patch below does what Paul McKenney suggested in the previous thread. Signed-off-by: Dave Jones Reviewed-by: Paul E. McKenney Acked-by: Paul Moore Cc: Eric Paris Signed-off-by: Andrew Morton Signed-off-by: James Morris Signed-off-by: Greg Kroah-Hartman --- security/selinux/netnode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/security/selinux/netnode.c +++ b/security/selinux/netnode.c @@ -174,7 +174,8 @@ static void sel_netnode_insert(struct se if (sel_netnode_hash[idx].size == SEL_NETNODE_HASH_BKT_LIMIT) { struct sel_netnode *tail; tail = list_entry( - rcu_dereference(sel_netnode_hash[idx].list.prev), + rcu_dereference_protected(sel_netnode_hash[idx].list.prev, + lockdep_is_held(&sel_netnode_lock)), struct sel_netnode, list); list_del_rcu(&tail->list); kfree_rcu(tail, rcu); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/