Squashfs: fix corruption checks in squashfs_readdir()
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>
diff --git a/fs/squashfs/dir.c b/fs/squashfs/dir.c
index f7f527b..1192084 100644
--- a/fs/squashfs/dir.c
+++ b/fs/squashfs/dir.c
@@ -105,9 +105,8 @@
struct inode *inode = file_inode(file);
struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
u64 block = squashfs_i(inode)->start + msblk->directory_table;
- int offset = squashfs_i(inode)->offset, length, dir_count, size,
- type, err;
- unsigned int inode_number;
+ int offset = squashfs_i(inode)->offset, length, type, err;
+ unsigned int inode_number, dir_count, size;
struct squashfs_dir_header dirh;
struct squashfs_dir_entry *dire;