Commit 52e9ce1c authored Sep 03, 2013 by Phillip Lougher

Squashfs: fix corruption checks in squashfs_lookup()



The dir_count and size fields when read from disk are sanity
checked for correctness.  However, the sanity checks only check the
values are not greater than expected.  As dir_count and size were
incorrectly defined as signed ints, this can lead to corrupted values
appearing as negative which are not trapped.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>

parent 9dbc41d5

fs/squashfs/namei.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -147,7 +147,8 @@ static struct dentry squashfs_lookup(struct inode dir, struct dentry *dentry,
		struct squashfs_dir_entry *dire;
		u64 block = squashfs_i(dir)->start + msblk->directory_table;
		int offset = squashfs_i(dir)->offset;
		int err, length, dir_count, size;
		int err, length;
		unsigned int dir_count, size;

		TRACE("Entered squashfs_lookup [%llx:%x]\n", block, offset);