Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752893AbdHRN2K (ORCPT ); Fri, 18 Aug 2017 09:28:10 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:55636 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752876AbdHRNPw (ORCPT ); Fri, 18 Aug 2017 09:15:52 -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, "Dan Carpenter" , "Steve French" Date: Fri, 18 Aug 2017 14:13:20 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 107/134] cifs: small underflow in cnvrtDosUnixTm() In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 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: 1273 Lines: 38 3.16.47-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit 564277eceeca01e02b1ef3e141cfb939184601b4 upstream. January is month 1. There is no zero-th month. If someone passes a zero month then it means we read from one space before the start of the total_days_of_prev_months[] array. We may as well also be strict about days as well. Fixes: 1bd5bbcb6531 ("[CIFS] Legacy time handling for Win9x and OS/2 part 1") Signed-off-by: Dan Carpenter Signed-off-by: Steve French Signed-off-by: Ben Hutchings --- fs/cifs/netmisc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/fs/cifs/netmisc.c +++ b/fs/cifs/netmisc.c @@ -966,10 +966,10 @@ struct timespec cnvrtDosUnixTm(__le16 le cifs_dbg(VFS, "illegal hours %d\n", st->Hours); days = sd->Day; month = sd->Month; - if ((days > 31) || (month > 12)) { + if (days < 1 || days > 31 || month < 1 || month > 12) { cifs_dbg(VFS, "illegal date, month %d day: %d\n", month, days); - if (month > 12) - month = 12; + days = clamp(days, 1, 31); + month = clamp(month, 1, 12); } month -= 1; days += total_days_of_prev_months[month];