From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753459Ab3AVO6u (ORCPT ); Tue, 22 Jan 2013 09:58:50 -0500 Received: from mail-vb0-f47.google.com ([209.85.212.47]:55236 "EHLO mail-vb0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753235Ab3AVO6s (ORCPT ); Tue, 22 Jan 2013 09:58:48 -0500 From: Xi Wang To: linux-kernel@vger.kernel.org Cc: "Eric W. Biederman" , Xi Wang , stable@vger.kernel.org Subject: [PATCH] sysctl: fix null checking in bin_dn_node_address() Date: Tue, 22 Jan 2013 09:58:25 -0500 Message-Id: <1358866705-30690-1-git-send-email-xi.wang@gmail.com> X-Mailer: git-send-email 1.7.10.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The null check of `strchr() + 1' is broken, which is always non-null, leading to OOB read. Instead, check the result of strchr(). Signed-off-by: Xi Wang Cc: stable@vger.kernel.org --- kernel/sysctl_binary.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c index 5a63844..0ddf3a0 100644 --- a/kernel/sysctl_binary.c +++ b/kernel/sysctl_binary.c @@ -1194,9 +1194,10 @@ static ssize_t bin_dn_node_address(struct file *file, /* Convert the decnet address to binary */ result = -EIO; - nodep = strchr(buf, '.') + 1; + nodep = strchr(buf, '.'); if (!nodep) goto out; + ++nodep; area = simple_strtoul(buf, NULL, 10); node = simple_strtoul(nodep, NULL, 10); -- 1.7.10.4