From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757349AbcAPARJ (ORCPT ); Fri, 15 Jan 2016 19:17:09 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:37064 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756900AbcAPAHY (ORCPT ); Fri, 15 Jan 2016 19:07:24 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Cong Wang , "David S. Miller" , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 274/305] addrconf: always initialize sysctl table data Date: Fri, 15 Jan 2016 16:01:28 -0800 Message-Id: <1452902519-2754-275-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1452902519-2754-1-git-send-email-kamal@canonical.com> References: <1452902519-2754-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 4.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.2.8-ckt2 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: WANG Cong commit 5449a5ca9bc27dd51a462de7ca0b1cd861cd2bd0 upstream. When sysctl performs restrict writes, it allows to write from a middle position of a sysctl file, which requires us to initialize the table data before calling proc_dostring() for the write case. Fixes: 3d1bec99320d ("ipv6: introduce secret_stable to ipv6_devconf") Reported-by: Sasha Levin Acked-by: Hannes Frederic Sowa Tested-by: Sasha Levin Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Kamal Mostafa --- net/ipv6/addrconf.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index f4d78a4..d956e30 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -5269,13 +5269,10 @@ static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write, goto out; } - if (!write) { - err = snprintf(str, sizeof(str), "%pI6", - &secret->secret); - if (err >= sizeof(str)) { - err = -EIO; - goto out; - } + err = snprintf(str, sizeof(str), "%pI6", &secret->secret); + if (err >= sizeof(str)) { + err = -EIO; + goto out; } err = proc_dostring(&lctl, write, buffer, lenp, ppos); -- 1.9.1