From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752131AbaHXFld (ORCPT ); Sun, 24 Aug 2014 01:41:33 -0400 Received: from mail-pa0-f53.google.com ([209.85.220.53]:34703 "EHLO mail-pa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751136AbaHXFlc (ORCPT ); Sun, 24 Aug 2014 01:41:32 -0400 From: Brian Norris To: Chris Mason Cc: Josef Bacik , linux-btrfs@vger.kernel.org, Linux Kernel , Brian Norris Subject: [PATCH] fs: btrfs: fix potential overflow Date: Sat, 23 Aug 2014 22:41:21 -0700 Message-Id: <1408858881-30497-1-git-send-email-computersforpeace@gmail.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It looks like this intended to be 64-bit arithmetic, but it's actually performed as 32-bit. Fix that. (Note that 'increment' was being initialized twice, so this patch removes one of those.) Caught by Coverity Scan (CID 1201422). Signed-off-by: Brian Norris --- Untested fs/btrfs/scrub.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index b6d198f5181e..b1a8127737b4 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -2320,26 +2320,26 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, do_div(nstripes, map->stripe_len); if (map->type & BTRFS_BLOCK_GROUP_RAID0) { offset = map->stripe_len * num; - increment = map->stripe_len * map->num_stripes; + increment *= map->num_stripes; mirror_num = 1; } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { int factor = map->num_stripes / map->sub_stripes; offset = map->stripe_len * (num / map->sub_stripes); - increment = map->stripe_len * factor; + increment *= factor; mirror_num = num % map->sub_stripes + 1; } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { - increment = map->stripe_len; + increment *= 1; mirror_num = num % map->num_stripes + 1; } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { - increment = map->stripe_len; + increment *= 1; mirror_num = num % map->num_stripes + 1; } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { get_raid56_logic_offset(physical, num, map, &offset); - increment = map->stripe_len * nr_data_stripes(map); + increment *= nr_data_stripes(map); mirror_num = 1; } else { - increment = map->stripe_len; + increment *= 1; mirror_num = 1; } -- 1.7.9.5