[PATCH 3.14 39/64] ext4: check for zero length extent explicitly

Path	csiph.com!aioe.org!news.ecp.fr!news2.arglkargh.de!newsfeed.fsmpi.rwth-aachen.de!newsfeed.straub-nv.de!weretis.net!feeder4.news.weretis.net!storethat.news.telefonica.de!telefonica.de!news.panservice.it!bofh.it!news.nic.it!robomod
From	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Newsgroups	linux.kernel
Subject	[PATCH 3.14 39/64] ext4: check for zero length extent explicitly
Date	Wed, 03 Jun 2015 14:20:02 +0200
Message-ID	<pxfOi-E4-29@gated-at.bofh.it> (permalink)
References	<pxfOh-E4-7@gated-at.bofh.it>
X-Original-To	linux-kernel@vger.kernel.org
X-Mailer	git-send-email 2.4.2
User-Agent	quilt/0.64
MIME-Version	1.0
Content-Type	text/plain; charset=ISO-8859-15
Sender	robomod@news.nic.it
List-ID	<linux-kernel.vger.kernel.org>
X-Mailing-List	linux-kernel@vger.kernel.org
Approved	robomod@news.nic.it
Lines	42
Organization	linux.* mail to news gateway
X-Original-Cc	Greg Kroah-Hartman <gregkh@linuxfoundation.org>, stable@vger.kernel.org, Eryu Guan <guaneryu@gmail.com>, Theodore Tso <tytso@mit.edu>
X-Original-Date	Wed, 3 Jun 2015 20:43:07 +0900
X-Original-Message-ID	<20150603063930.121494568@linuxfoundation.org>
X-Original-References	<20150603063928.472620468@linuxfoundation.org>
X-Original-Sender	linux-kernel-owner@vger.kernel.org
Xref	aioe.org linux.kernel:1157426

Show key headers only | View raw

3.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eryu Guan <guaneryu@gmail.com>

commit 2f974865ffdfe7b9f46a9940836c8b167342563d upstream.

The following commit introduced a bug when checking for zero length extent

5946d08 ext4: check for overlapping extents in ext4_valid_extent_entries()

Zero length extent could pass the check if lblock is zero.

Adding the explicit check for zero length back.

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/ext4/extents.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -361,7 +361,7 @@ static int ext4_valid_extent(struct inod
 	ext4_lblk_t lblock = le32_to_cpu(ext->ee_block);
 	ext4_lblk_t last = lblock + len - 1;
 
-	if (lblock > last)
+	if (len == 0 || lblock > last)
 		return 0;
 	return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len);
 }


--
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/

Back to linux.kernel | Previous | Next | Find similar | Unroll thread

Thread

[PATCH 3.14 39/64] ext4: check for zero length extent explicitly Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2015-06-03 14:20 +0200

csiph-web