Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933812Ab2KZRMw (ORCPT ); Mon, 26 Nov 2012 12:12:52 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:48001 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932237Ab2KZRMq (ORCPT ); Mon, 26 Nov 2012 12:12:46 -0500 From: Herton Ronaldo Krzesinski To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Lukas Czerner , "Theodore Ts'o" , Herton Ronaldo Krzesinski Subject: [PATCH 206/270] ext4: Avoid underflow in ext4_trim_fs() Date: Mon, 26 Nov 2012 14:58:16 -0200 Message-Id: <1353949160-26803-207-git-send-email-herton.krzesinski@canonical.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1353949160-26803-1-git-send-email-herton.krzesinski@canonical.com> References: <1353949160-26803-1-git-send-email-herton.krzesinski@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1524 Lines: 45 3.5.7u1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Lukas Czerner commit 5de35e8d5c02d271c20e18337e01bc20e6ef472e upstream. Currently if len argument in ext4_trim_fs() is smaller than one block, the 'end' variable underflow. Avoid that by returning EINVAL if len is smaller than file system block. Also remove useless unlikely(). Signed-off-by: Lukas Czerner Signed-off-by: "Theodore Ts'o" Signed-off-by: Herton Ronaldo Krzesinski --- fs/ext4/mballoc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 70f97a5..af848bb 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4983,8 +4983,9 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) end = start + (range->len >> sb->s_blocksize_bits) - 1; minlen = range->minlen >> sb->s_blocksize_bits; - if (unlikely(minlen > EXT4_CLUSTERS_PER_GROUP(sb)) || - unlikely(start >= max_blks)) + if (minlen > EXT4_CLUSTERS_PER_GROUP(sb) || + start >= max_blks || + range->len < sb->s_blocksize) return -EINVAL; if (end >= max_blks) end = max_blks - 1; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/