Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755141Ab3JUJec (ORCPT ); Mon, 21 Oct 2013 05:34:32 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:39274 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753054Ab3JUIuR (ORCPT ); Mon, 21 Oct 2013 04:50:17 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Andrey Konovalov" , "David S. Miller" , "Eric Dumazet" , "Dmitry Vyukov" Date: Mon, 21 Oct 2013 09:46:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 003/149] fib_trie: remove potential out of bound access In-Reply-To: X-SA-Exim-Connect-IP: 212.20.242.100 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1814 Lines: 58 3.2.52-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit aab515d7c32a34300312416c50314e755ea6f765 ] AddressSanitizer [1] dynamic checker pointed a potential out of bound access in leaf_walk_rcu() We could allocate one more slot in tnode_new() to leave the prefetch() in-place but it looks not worth the pain. Bug added in commit 82cfbb008572b ("[IPV4] fib_trie: iterator recode") [1] : https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel Reported-by: Andrey Konovalov Signed-off-by: Eric Dumazet Cc: Dmitry Vyukov Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/ipv4/fib_trie.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index cd2d639..c7c6724 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -72,7 +72,6 @@ #include #include #include -#include #include #include #include @@ -1773,10 +1772,8 @@ static struct leaf *leaf_walk_rcu(struct tnode *p, struct rt_trie_node *c) if (!c) continue; - if (IS_LEAF(c)) { - prefetch(rcu_dereference_rtnl(p->child[idx])); + if (IS_LEAF(c)) return (struct leaf *) c; - } /* Rescan start scanning in new node */ p = (struct tnode *) c; -- 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/