The le64_to_cpu() forces the calculation to be unsigned, with
the effect that it can underflow leading to an incorrect large
value.
This bug only triggers in rare(ish) circumstances, an empty file
encoded as an extended regular file or a completely sparse file.
Normally empty files are encoded as a regular file rather than as
an extended regular file (and the regular file i_blocks calculation
doesn't have this bug). To save space regular file inodes are
optimised to encode the most commonly occurring files. Less
common regular files are encoded using extended regular file inodes
which contain extra information.
Empty files with nlinks greater than 1, and or empty files
with extended attributes are encoded using extended regular file
inodes and they will hit this bug.
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
Replace remaining direct i_nlink updates with a new set_nlink()
updater function.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
My existing email address may stop working in a month or two, so update
email to one that will continue working.
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
Add new extended inode types that store the xattr_id field.
Also add the necessary code changes to make xattrs visibile.
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
Move zlib buffer init/destroy code into separate wrapper file. Also
make zlib z_stream field a void * removing the need to include zlib.h
for most files.
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>