From: Jan Kara <jack@suse.cz>
To: Ted Tso <tytso@mit.edu>
Cc: <linux-ext4@vger.kernel.org>,
Wolfgang Frisch <wolfgang.frisch@suse.com>,
Jan Kara <jack@suse.cz>
Subject: [PATCH] ext4: catch integer overflow in ext4_cache_extents
Date: Mon, 13 Jul 2020 14:58:18 +0200 [thread overview]
Message-ID: <20200713125818.21918-1-jack@suse.cz> (raw)
From: Wolfgang Frisch <wolfgang.frisch@suse.com>
When extent tree is corrupted we can hit BUG_ON in
ext4_es_cache_extent(). Check for this and abort caching instead of
crashing the machine.
Signed-off-by: Wolfgang Frisch <wolfgang.frisch@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
fs/ext4/extents.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 221f240eae60..e76d00fda104 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -471,6 +471,10 @@ static void ext4_cache_extents(struct inode *inode,
ext4_lblk_t lblk = le32_to_cpu(ex->ee_block);
int len = ext4_ext_get_actual_len(ex);
+ /* Corrupted extent tree? Stop caching... */
+ if (lblk + len < lblk || lblk + len > EXT4_MAX_LOGICAL_BLOCK)
+ return;
+
if (prev && (prev != lblk))
ext4_es_cache_extent(inode, prev, lblk - prev, ~0,
EXTENT_STATUS_HOLE);
--
2.16.4
next reply other threads:[~2020-07-13 12:58 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-13 12:58 Jan Kara [this message]
2020-07-13 13:44 ` [PATCH] ext4: catch integer overflow in ext4_cache_extents Ritesh Harjani
2020-07-14 12:31 ` Jan Kara
2020-07-15 11:53 ` Jan Kara
2020-07-15 17:25 ` Wolfgang Frisch
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