Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755522Ab3I3KMo (ORCPT ); Mon, 30 Sep 2013 06:12:44 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:43539 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755443Ab3I3KMa (ORCPT ); Mon, 30 Sep 2013 06:12:30 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Eric Dumazet , Dmitry Vyukov , "David S. Miller" , Luis Henriques Subject: [PATCH 042/104] fib_trie: remove potential out of bound access Date: Mon, 30 Sep 2013 11:10:19 +0100 Message-Id: <1380535881-9239-43-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1380535881-9239-1-git-send-email-luis.henriques@canonical.com> References: <1380535881-9239-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1839 Lines: 60 3.5.7.22 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet commit aab515d7c32a34300312416c50314e755ea6f765 upstream. 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: Luis Henriques --- 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 30b88d7..424704a 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -71,7 +71,6 @@ #include #include #include -#include #include #include #include @@ -1772,10 +1771,8 @@ 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; -- 1.8.3.2 -- 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/