Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752386AbdFAQJR (ORCPT ); Thu, 1 Jun 2017 12:09:17 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33568 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752226AbdFAPpI (ORCPT ); Thu, 1 Jun 2017 11:45:08 -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, "Theodore Ts'o" Date: Thu, 01 Jun 2017 16:43:16 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 125/212] ext4: fix fencepost in s_first_meta_bg validation 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: 1160 Lines: 33 3.16.44-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Theodore Ts'o commit 2ba3e6e8afc9b6188b471f27cf2b5e3cf34e7af2 upstream. It is OK for s_first_meta_bg to be equal to the number of block group descriptor blocks. (It rarely happens, but it shouldn't cause any problems.) https://bugzilla.kernel.org/show_bug.cgi?id=194567 Fixes: 3a4b77cd47bb837b8557595ec7425f281f2ca1fe Signed-off-by: Theodore Ts'o [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- fs/ext4/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3916,7 +3916,7 @@ static int ext4_fill_super(struct super_ db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) / EXT4_DESC_PER_BLOCK(sb); if (EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG)) { - if (le32_to_cpu(es->s_first_meta_bg) >= db_count) { + if (le32_to_cpu(es->s_first_meta_bg) > db_count) { ext4_msg(sb, KERN_WARNING, "first meta block group too large: %u " "(group descriptor block count %u)",