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Author SHA1 Message Date
Linus Torvalds aab174f0df Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs update from Al Viro:

 - big one - consolidation of descriptor-related logics; almost all of
   that is moved to fs/file.c

   (BTW, I'm seriously tempted to rename the result to fd.c.  As it is,
   we have a situation when file_table.c is about handling of struct
   file and file.c is about handling of descriptor tables; the reasons
   are historical - file_table.c used to be about a static array of
   struct file we used to have way back).

   A lot of stray ends got cleaned up and converted to saner primitives,
   disgusting mess in android/binder.c is still disgusting, but at least
   doesn't poke so much in descriptor table guts anymore.  A bunch of
   relatively minor races got fixed in process, plus an ext4 struct file
   leak.

 - related thing - fget_light() partially unuglified; see fdget() in
   there (and yes, it generates the code as good as we used to have).

 - also related - bits of Cyrill's procfs stuff that got entangled into
   that work; _not_ all of it, just the initial move to fs/proc/fd.c and
   switch of fdinfo to seq_file.

 - Alex's fs/coredump.c spiltoff - the same story, had been easier to
   take that commit than mess with conflicts.  The rest is a separate
   pile, this was just a mechanical code movement.

 - a few misc patches all over the place.  Not all for this cycle,
   there'll be more (and quite a few currently sit in akpm's tree)."

Fix up trivial conflicts in the android binder driver, and some fairly
simple conflicts due to two different changes to the sock_alloc_file()
interface ("take descriptor handling from sock_alloc_file() to callers"
vs "net: Providing protocol type via system.sockprotoname xattr of
/proc/PID/fd entries" adding a dentry name to the socket)

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits)
  MAX_LFS_FILESIZE should be a loff_t
  compat: fs: Generic compat_sys_sendfile implementation
  fs: push rcu_barrier() from deactivate_locked_super() to filesystems
  btrfs: reada_extent doesn't need kref for refcount
  coredump: move core dump functionality into its own file
  coredump: prevent double-free on an error path in core dumper
  usb/gadget: fix misannotations
  fcntl: fix misannotations
  ceph: don't abuse d_delete() on failure exits
  hypfs: ->d_parent is never NULL or negative
  vfs: delete surplus inode NULL check
  switch simple cases of fget_light to fdget
  new helpers: fdget()/fdput()
  switch o2hb_region_dev_write() to fget_light()
  proc_map_files_readdir(): don't bother with grabbing files
  make get_file() return its argument
  vhost_set_vring(): turn pollstart/pollstop into bool
  switch prctl_set_mm_exe_file() to fget_light()
  switch xfs_find_handle() to fget_light()
  switch xfs_swapext() to fget_light()
  ...
2012-10-02 20:25:04 -07:00
Kirill A. Shutemov 8c0a853770 fs: push rcu_barrier() from deactivate_locked_super() to filesystems
There's no reason to call rcu_barrier() on every
deactivate_locked_super().  We only need to make sure that all delayed rcu
free inodes are flushed before we destroy related cache.

Removing rcu_barrier() from deactivate_locked_super() affects some fast
paths.  E.g.  on my machine exit_group() of a last process in IPC
namespace takes 0.07538s.  rcu_barrier() takes 0.05188s of that time.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-02 21:35:55 -04:00
Eric W. Biederman 61293ee274 userns: Convert squashfs to use kuid/kgid where appropriate
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-09-21 03:13:35 -07:00
Al Viro 00cd8dd3bf stop passing nameidata to ->lookup()
Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument.  And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:32 +04:00
Linus Torvalds 8563f8786e Add an extra mount time sanity check, plus some code cleanups and bug fixes.
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Merge tag 'squashfs-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next

Pull squashfs updates from Phillip Lougher:
 "Add an extra mount time sanity check, plus some code cleanups and bug
  fixes."

* tag 'squashfs-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next:
  Squashfs: add mount time sanity check for block_size and block_log match
  Squashfs: fix f_pos check in get_dir_index_using_offset
  Squashfs: get rid of obsolete definitions in header file
  Squashfs: remove redundant length initialisation in squashfs_lookup
  Squashfs: remove redundant length initialisation in squashfs_readdir
  Squashfs: update comment removing reference to zlib only
  Squashfs: use define instead of constant
2012-03-28 18:05:54 -07:00
Linus Torvalds e2a0883e40 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile 1 from Al Viro:
 "This is _not_ all; in particular, Miklos' and Jan's stuff is not there
  yet."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
  ext4: initialization of ext4_li_mtx needs to be done earlier
  debugfs-related mode_t whack-a-mole
  hfsplus: add an ioctl to bless files
  hfsplus: change finder_info to u32
  hfsplus: initialise userflags
  qnx4: new helper - try_extent()
  qnx4: get rid of qnx4_bread/qnx4_getblk
  take removal of PF_FORKNOEXEC to flush_old_exec()
  trim includes in inode.c
  um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
  um: embed ->stub_pages[] into mmu_context
  gadgetfs: list_for_each_safe() misuse
  ocfs2: fix leaks on failure exits in module_init
  ecryptfs: make register_filesystem() the last potential failure exit
  ntfs: forgets to unregister sysctls on register_filesystem() failure
  logfs: missing cleanup on register_filesystem() failure
  jfs: mising cleanup on register_filesystem() failure
  make configfs_pin_fs() return root dentry on success
  configfs: configfs_create_dir() has parent dentry in dentry->d_parent
  configfs: sanitize configfs_create()
  ...
2012-03-21 13:36:41 -07:00
Al Viro 48fde701af switch open-coded instances of d_make_root() to new helper
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20 21:29:35 -04:00
Cong Wang 53b55e5589 squashfs: remove the second argument of k[un]map_atomic()
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-20 21:48:25 +08:00
Phillip Lougher 4b0180a49f Squashfs: add mount time sanity check for block_size and block_log match
Squashfs currently has a sanity check for block_size less than or
equal to the maximum block_size (1 Mbyte).  This catches some
superblock corruption, but obviously with a block_size maximum
of 1 Mbyte there's 7 correct values (4K, 8K, 16K, 32K, ... etc) and
a lot of incorrect values which are not caught by this check.

The Squashfs superblock, however, has both a block_size and
a block_log (2^block_log == block_size).  Checking that the block_size
matches the block_log is a much more robust check.  Corruption of the
superblock is unlikely to produce values which match, and it also
ensures the block_size is an exact power of two.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2012-03-10 03:01:02 +00:00
Phillip Lougher 2158d3fd27 Squashfs: fix f_pos check in get_dir_index_using_offset
One off error in the f_pos check.  If f_pos is 3 or less don't
bother reading the index because we're at the start of the
directory, and we obviously already know where that is on disk.

This eliminates an unnecessary read.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2012-03-10 03:01:02 +00:00
Phillip Lougher 47f4396e51 Squashfs: get rid of obsolete definitions in header file
Most of these were never used by the kernel code, but belong to
the time when the header file was used by both the kernel code
and the user space tools.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2012-03-10 03:01:01 +00:00
Phillip Lougher bd3a518948 Squashfs: remove redundant length initialisation in squashfs_lookup
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2012-03-10 03:01:01 +00:00
Phillip Lougher 68a8c397bf Squashfs: remove redundant length initialisation in squashfs_readdir
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2012-03-10 03:01:01 +00:00
Phillip Lougher ec9267b61d Squashfs: update comment removing reference to zlib only
Comment was written when Squashfs only supported zlib compression.
This comment is now misleading given Squashfs supports other
compression algorithms.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2012-03-10 03:01:00 +00:00
Ajeet Yadav 4826d83d9c Squashfs: use define instead of constant
Its better to use defined name instead of constant

Signed-off-by: Ajeet Yadav <ajeet.yadav.77@gmail.com>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2012-03-10 03:00:54 +00:00
Linus Torvalds 96e80a7851 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next:
  Squashfs: fix i_blocks calculation with extended regular files
  Squashfs: fix mount time sanity check for corrupted superblock
  Squashfs: optimise squashfs_cache_get entry search
  Squashfs: Update documentation to include xattrs
  Squashfs: add missing block release on error condition
2012-01-13 10:34:57 -08:00
Al Viro 6b520e0565 vfs: fix the stupidity with i_dentry in inode destructors
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from ->destroy_inode() instances...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:52:40 -05:00
Phillip Lougher 3d4a1c80c4 Squashfs: fix i_blocks calculation with extended regular files
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>
2012-01-03 04:00:43 +00:00
Phillip Lougher cc37f75a9f Squashfs: fix mount time sanity check for corrupted superblock
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@squashfs.org.uk>
2012-01-02 17:47:14 +00:00
Ajeet Yadav d7fbd89338 Squashfs: optimise squashfs_cache_get entry search
squashfs_cache_get() iterates over all entries to search for
 block its looking for. Often get() / put() are called for
 same block.

If we cache the current entry index, then we can optimise the
subsequent *_get() calls.

Signed-off-by: Ajeet Yadav <ajeet.yadav.77@gmail.com>
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2011-12-30 01:24:13 +00:00
Phillip Lougher e552a59668 Squashfs: add missing block release on error condition
squashfs_read_metadata forgets to release the cache block if
an error has occurred.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2011-12-30 01:20:14 +00:00
Linus Torvalds 044595d4e4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-next:
  Squashfs: Add an option to set dev block size to 4K
2011-11-04 16:48:37 -07:00
Phillip Lougher 7657cacf47 Squashfs: Add an option to set dev block size to 4K
This commit adds an option to set the device block size used to 4K.

By default Squashfs sets the device block size (sb_min_blocksize) to 1K
or the smallest block size supported by the block device (if larger).
This, because blocks are packed together and unaligned in Squashfs,
should reduce latency.

This, however, gives poor performance on MTD NAND devices where
the optimal I/O size is 4K (even though the devices can support
smaller block sizes).

Using a 4K device block size may also improve overall I/O
performance for some file access patterns (e.g. sequential
accesses of files in filesystem order) on all media.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2011-11-02 17:25:50 +00:00
Miklos Szeredi bfe8684869 filesystems: add set_nlink()
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>
2011-11-02 12:53:43 +01:00
Paul Bolle 395cf9691d doc: fix broken references
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-27 18:08:04 +02:00
Linus Torvalds 91d44d9999 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
  Squashfs: Make ZLIB compression support optional
  Squashfs: Update documentation for XZ and add squashfs-tools devel tree
2011-07-25 22:50:35 -07:00
Phillip Lougher cc6d349714 Squashfs: Make ZLIB compression support optional
Squashfs now supports XZ and LZO compression in addition to ZLIB.
As such it no longer makes sense to always include ZLIB support.
In particular embedded systems may only use LZO or XZ compression, and
the ability to exclude ZLIB support will reduce kernel size.

Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
2011-07-22 03:01:28 +01:00
Al Viro a9049376ee make d_splice_alias(ERR_PTR(err), dentry) = ERR_PTR(err)
... and simplify the living hell out of callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:44:26 -04:00
Al Viro 0c1aa9a952 deuglify squashfs_lookup()
d_splice_alias(NULL, dentry) is equivalent to d_add(dentry, NULL), NULL
so no need for that if (inode) ... in there (or ERR_PTR(0), for that
matter)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:44:24 -04:00
Linus Torvalds 2ff55e98d6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
  Squashfs: Fix sanity check patches on big-endian systems
2011-05-29 11:19:45 -07:00
Phillip Lougher d5b72ce15e Squashfs: Fix sanity check patches on big-endian systems
le64 values should be swapped when accessing on
big-endian systems.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-05-29 10:03:09 +01:00
Linus Torvalds bc9bc72e2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus:
  Squashfs: update email address
  Squashfs: add extra sanity checks at mount time
  Squashfs: add sanity checks to fragment reading at mount time
  Squashfs: add sanity checks to lookup table reading at mount time
  Squashfs: add sanity checks to id reading at mount time
  Squashfs: add sanity checks to xattr reading at mount time
  Squashfs: reverse order of filesystem table reading
  Squashfs: move table allocation into squashfs_read_table()
2011-05-26 17:27:35 -07:00
Phillip Lougher d7f2ff6718 Squashfs: update email address
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>
2011-05-26 10:49:11 +01:00
Phillip Lougher 1094a4a611 Squashfs: add extra sanity checks at mount time
Add some extra sanity checks of the inode and directory structures.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-05-25 18:21:33 +01:00
Phillip Lougher 1cac63cc9b Squashfs: add sanity checks to fragment reading at mount time
Fsfuzzer generates corrupted filesystems which throw a warn_on in
kmalloc.  One of these is due to a corrupted superblock fragments field.
Fix this by checking that the number of bytes to be read (and allocated)
does not extend into the next filesystem structure.

Also add a couple of other sanity checks of the mount-time fragment table
structures.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-05-25 18:21:33 +01:00
Phillip Lougher ac51a0a713 Squashfs: add sanity checks to lookup table reading at mount time
Fsfuzzer generates corrupted filesystems which throw a warn_on in
kmalloc.  One of these is due to a corrupted superblock inodes field.
Fix this by checking that the number of bytes to be read (and allocated)
does not extend into the next filesystem structure.

Also add a couple of other sanity checks of the mount-time lookup table
structures.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-05-25 18:21:32 +01:00
Phillip Lougher 37986f63c8 Squashfs: add sanity checks to id reading at mount time
Fsfuzzer generates corrupted filesystems which throw a warn_on in
kmalloc.  One of these is due to a corrupted superblock no_ids field.
Fix this by checking that the number of bytes to be read (and allocated)
does not extend into the next filesystem structure.

Also add a couple of other sanity checks of the mount-time id table
structures.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-05-25 18:21:32 +01:00
Phillip Lougher 6f04864515 Squashfs: add sanity checks to xattr reading at mount time
These checks add sanity checking of the mount-time xattr structures.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-05-25 18:21:31 +01:00
Phillip Lougher 76e002f755 Squashfs: reverse order of filesystem table reading
Reverse order of table reading from mostly first to last in placement
order, to last to first.  This is to enable extra superblock sanity
checks to be added in later patches.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-05-25 18:21:31 +01:00
Phillip Lougher 82de647e1f Squashfs: move table allocation into squashfs_read_table()
This eliminates a lot of duplicate code.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-05-25 18:21:31 +01:00
Justin P. Mattock 70f23fd66b treewide: fix a few typos in comments
- kenrel -> kernel
- whetehr -> whether
- ttt -> tt
- sss -> ss

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-05-10 10:16:21 +02:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Phillip Lougher 117a91e0f2 Squashfs: Use vmalloc rather than kmalloc for zlib workspace
Bugzilla bug 31422 reports occasional "page allocation failure. order:4"
at Squashfs mount time.  Fix this by making zlib workspace allocation
use vmalloc rather than kmalloc.

Reported-by: Mehmet Giritli <mehmet@giritli.eu>
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-03-22 23:01:26 +00:00
Phillip Lougher 44cff8a9ee Squashfs: handle corruption of directory structure
Handle the rare case where a directory metadata block is uncompressed and
corrupted, leading to a kernel oops in directory scanning (memcpy).
Normally corruption is detected at the decompression stage and dealt with
then, however, this will not happen if:

- metadata isn't compressed (users can optionally request no metadata
  compression), or
- the compressed metadata block was larger than the original, in which
  case the uncompressed version was used, or
- the data was corrupt after decompression

This patch fixes this by adding some sanity checks against known maximum
values.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-03-16 01:04:18 +00:00
Phillip Lougher 003a3194d3 Squashfs: wrap squashfs_mount() definition
Squashfs_get_sb() to squashfs_mount() conversion (commit 152a0836)
results in line over 80 characters.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-02-28 18:43:48 +00:00
Phillip Lougher 3ad126641c Squashfs: xz_wrapper doesn't need to include squashfs_fs_i.h anymore
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-02-28 18:35:44 +00:00
Phillip Lougher 681ffe2e43 Squashfs: Update Kconfig help text to include xz compression
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-02-28 18:35:28 +00:00
Phillip Lougher ff750311d3 Squashfs: add compression options support to xz decompressor
Pass the dictionary size used to compress datablocks.  Using a
dictionary size less than the block size saves memory overhead, in many
cases without adversely affecting compression ratio.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-02-28 18:34:24 +00:00
Phillip Lougher b7fc0ff09d Squashfs: extend decompressor framework to handle compression options
Extend decompressor framework to handle compression options stored in
the filesystem.  These options can be used by the relevant decompressor
at initialisation time to over-ride defaults.

The presence of compression options in the filesystem is indicated by
the COMP_OPT filesystem flag.  If present the data is read from the
filesystem and passed to the decompressor init function.  The decompressor
init function signature has been extended to take this data.

Also update the init function signature in the glib, lzo and xz
decompressor wrappers.

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
2011-02-28 18:21:59 +00:00
Phillip Lougher 3689456b4b squashfs: fix use of uninitialised variable in zlib & xz decompressors
Fix potential use of uninitialised variable caused by recent
decompressor code optimisations.

In zlib_uncompress (zlib_wrapper.c) we have

	int zlib_err, zlib_init = 0;
	...
	do {
		...
			if (avail == 0) {
				offset = 0;
				put_bh(bh[k++]);
				continue;
			}
		...
		zlib_err = zlib_inflate(stream, Z_SYNC_FLUSH);
		...
	} while (zlib_err == Z_OK);

If continue is executed (avail == 0) then the while condition will be
evaluated testing zlib_err, which is uninitialised first time around the
loop.

Fix this by getting rid of the 'if (avail == 0)' condition test, this
edge condition should not be being handled in the decompressor code, and
instead handle it generically in the caller code.

Similarly for xz_wrapper.c.

Incidentally, on most architectures (bar Mips and Parisc), no
uninitialised variable warning is generated by gcc, this is because the
while condition test on continue is optimised out and not performed
(when executing continue zlib_err has not been changed since entering
the loop, and logically if the while condition was true previously, then
it's still true).

Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
Reported-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-26 10:50:05 +10:00