From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933774AbbCFKSO (ORCPT ); Fri, 6 Mar 2015 05:18:14 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:44694 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933184AbbCFKAo (ORCPT ); Fri, 6 Mar 2015 05:00:44 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Thomas Gleixner , Ingo Molnar , Sasha Levin , John Stultz , Luis Henriques Subject: [PATCH 3.16.y-ckt 132/183] time: adjtimex: Validate the ADJ_FREQUENCY values Date: Fri, 6 Mar 2015 09:57:03 +0000 Message-Id: <1425635874-19087-133-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1425635874-19087-1-git-send-email-luis.henriques@canonical.com> References: <1425635874-19087-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt8 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Sasha Levin commit 5e5aeb4367b450a28f447f6d5ab57d8f2ab16a5f upstream. Verify that the frequency value from userspace is valid and makes sense. Unverified values can cause overflows later on. Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Sasha Levin [jstultz: Fix up bug for negative values and drop redunent cap check] Signed-off-by: John Stultz Signed-off-by: Luis Henriques --- kernel/time/ntp.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 33db43a39515..3fca3fdd7c82 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -632,6 +632,13 @@ int ntp_validate_timex(struct timex *txc) if ((txc->modes & ADJ_SETOFFSET) && (!capable(CAP_SYS_TIME))) return -EPERM; + if (txc->modes & ADJ_FREQUENCY) { + if (LONG_MIN / PPM_SCALE > txc->freq) + return -EINVAL; + if (LONG_MAX / PPM_SCALE < txc->freq) + return -EINVAL; + } + return 0; }