[ 94/95] Squashfs: fix mount time sanity check for corrupted superblock

From: Ben Hutchings
Date: Sun Sep 09 2012 - 19:32:24 EST


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

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

From: Phillip Lougher <phillip@xxxxxxxxxxxxxxx>

commit cc37f75a9ffbbfcb1c3297534f293c8284e3c5a6 upstream.

A Squashfs filesystem containing nothing but an empty directory,
although unusual and ultimately pointless, is still valid.

The directory_table >= next_table sanity check rejects these
filesystems as invalid because the directory_table is empty and
equal to next_table.

Signed-off-by: Phillip Lougher <phillip@xxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
fs/squashfs/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
index 2da1715..4619247 100644
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -290,7 +290,7 @@ handle_fragments:

check_directory_table:
/* Sanity check directory_table */
- if (msblk->directory_table >= next_table) {
+ if (msblk->directory_table > next_table) {
err = -EINVAL;
goto failed_mount;
}


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