linux-stable.git/fs/xfs, branch linux-3.1.y

xfs: fix acl count validation in xfs_acl_from_disk()

2012-01-12T19:33:47+00:00

commit 093019cf1b18dd31b2c3b77acce4e000e2cbc9ce upstream.

Commit fa8b18ed didn't prevent the integer overflow and possible
memory corruption.  "count" can go negative and bypass the check.

Signed-off-by: Xi Wang 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Ben Myers 
Signed-off-by: Greg Kroah-Hartman

xfs: validate acl count

2012-01-12T19:33:46+00:00

commit fa8b18edd752a8b4e9d1ee2cd615b82c93cf8bba upstream.

This prevents in-memory corruption and possible panics if the on-disk
ACL is badly corrupted.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Ben Myers 
Signed-off-by: Greg Kroah-Hartman

xfs: use doalloc flag in xfs_qm_dqattach_one()

2011-12-09T16:54:30+00:00

commit db3e74b582915d66e10b0c73a62763418f54c340 upstream.

The doalloc arg in xfs_qm_dqattach_one() is a flag that indicates
whether a new area to handle quota information will be allocated
if needed. Originally, it was passed to xfs_qm_dqget(), but has
been removed by the following commit (probably by mistake):

	commit 8e9b6e7fa4544ea8a0e030c8987b918509c8ff47
	Author: Christoph Hellwig 
	Date:   Sun Feb 8 21:51:42 2009 +0100

	xfs: remove the unused XFS_QMOPT_DQLOCK flag

As the result, xfs_qm_dqget() called from xfs_qm_dqattach_one()
never allocates the new area even if it is needed.

This patch gives the doalloc arg to xfs_qm_dqget() in
xfs_qm_dqattach_one() to fix this problem.

Signed-off-by: Mitsuo Hayasaka 
Cc: Alex Elder 
Cc: Christoph Hellwig 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Ben Myers 
Signed-off-by: Greg Kroah-Hartman

xfs: Fix possible memory corruption in xfs_readlink

2011-12-09T16:54:30+00:00

commit b52a360b2aa1c59ba9970fb0f52bbb093fcc7a24 upstream.

Fixes a possible memory corruption when the link is larger than
MAXPATHLEN and XFS_DEBUG is not enabled. This also remove the
S_ISLNK assert, since the inode mode is checked previously in
xfs_readlink_by_handle() and via VFS.

Updated to address concerns raised by Ben Hutchings about the loose
attention paid to 32- vs 64-bit values, and the lack of handling a
potentially negative pathlen value:
 - Changed type of "pathlen" to be xfs_fsize_t, to match that of
   ip->i_d.di_size
 - Added checking for a negative pathlen to the too-long pathlen
   test, and generalized the message that gets reported in that case
   to reflect the change
As a result, if a negative pathlen were encountered, this function
would return EFSCORRUPTED (and would fail an assertion for a debug
build)--just as would a too-long pathlen.

Signed-off-by: Alex Elder 
Signed-off-by: Carlos Maiolino 
Reviewed-by: Christoph Hellwig 
Cc: Ben Myers 
Signed-off-by: Greg Kroah-Hartman

xfs: fix buffer flushing during unmount

2011-12-09T16:54:30+00:00

commit 87c7bec7fc3377b3873eb3a0f4b603981ea16ebb upstream.

The code to flush buffers in the umount code is a bit iffy: we first
flush all delwri buffers out, but then might be able to queue up a
new one when logging the sb counts.  On a normal shutdown that one
would get flushed out when doing the synchronous superblock write in
xfs_unmountfs_writesb, but we skip that one if the filesystem has
been shut down.

Fix this by moving the delwri list flushing until just before unmounting
the log, and while we're at it also remove the superflous delwri list
and buffer lru flusing for the rt and log device that can never have
cached or delwri buffers.

Signed-off-by: Christoph Hellwig 
Reported-by: Amit Sahrawat 
Tested-by: Amit Sahrawat 
Signed-off-by: Alex Elder 
Cc: Ben Myers 
Signed-off-by: Greg Kroah-Hartman

xfs: Return -EIO when xfs_vn_getattr() failed

2011-12-09T16:54:30+00:00

commit ed32201e65e15f3e6955cb84cbb544b08f81e5a5 upstream.

An attribute of inode can be fetched via xfs_vn_getattr() in XFS.
Currently it returns EIO, not negative value, when it failed.  As a
result, the system call returns not negative value even though an
error occured. The stat(2), ls and mv commands cannot handle this
error and do not work correctly.

This patch fixes this bug, and returns -EIO, not EIO when an error
is detected in xfs_vn_getattr().

Signed-off-by: Mitsuo Hayasaka 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Alex Elder 
Cc: Ben Myers 
Signed-off-by: Greg Kroah-Hartman

xfs: avoid direct I/O write vs buffered I/O race

2011-12-09T16:54:29+00:00

commit c58cb165bd44de8aaee9755a144136ae743be116 upstream.

Currently a buffered reader or writer can add pages to the pagecache
while we are waiting for the iolock in xfs_file_dio_aio_write.  Prevent
this by re-checking mapping->nrpages after we got the iolock, and if
nessecary upgrade the lock to exclusive mode.  To simplify this a bit
only take the ilock inside of xfs_file_aio_write_checks.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Dave Chinner 
Signed-off-by: Alex Elder 
Cc: Ben Myers 
Signed-off-by: Greg Kroah-Hartman

xfs: don't serialise direct IO reads on page cache checks

2011-12-09T16:54:29+00:00

commit 0c38a2512df272b14ef4238b476a2e4f70da1479 upstream.

There is no need to grab the i_mutex of the IO lock in exclusive
mode if we don't need to invalidate the page cache. Taking these
locks on every direct IO effective serialises them as taking the IO
lock in exclusive mode has to wait for all shared holders to drop
the lock. That only happens when IO is complete, so effective it
prevents dispatch of concurrent direct IO reads to the same inode.

Fix this by taking the IO lock shared to check the page cache state,
and only then drop it and take the IO lock exclusively if there is
work to be done. Hence for the normal direct IO case, no exclusive
locking will occur.

Signed-off-by: Dave Chinner 
Tested-by: Joern Engel 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Alex Elder 
Cc: Ben Myers 
Signed-off-by: Greg Kroah-Hartman

xfs: revert to using a kthread for AIL pushing

2011-10-11T16:02:49+00:00

Currently we have a few issues with the way the workqueue code is used to
implement AIL pushing:

 - it accidentally uses the same workqueue as the syncer action, and thus
   can be prevented from running if there are enough sync actions active
   in the system.
 - it doesn't use the HIGHPRI flag to queue at the head of the queue of
   work items

At this point I'm not confident enough in getting all the workqueue flags and
tweaks right to provide a perfectly reliable execution context for AIL
pushing, which is the most important piece in XFS to make forward progress
when the log fills.

Revert back to use a kthread per filesystem which fixes all the above issues
at the cost of having a task struct and stack around for each mounted
filesystem.  In addition this also gives us much better ways to diagnose
any issues involving hung AIL pushing and removes a small amount of code.

Signed-off-by: Christoph Hellwig 
Reported-by: Stefan Priebe 
Tested-by: Stefan Priebe 
Reviewed-by: Dave Chinner 
Signed-off-by: Alex Elder

xfs: force the log if we encounter pinned buffers in .iop_pushbuf

2011-10-11T16:02:48+00:00

We need to check for pinned buffers even in .iop_pushbuf given that inode
items flush into the same buffers that may be pinned directly due operations
on the unlinked inode list operating directly on buffers.  To do this add a
return value to .iop_pushbuf that tells the AIL push about this and use
the existing log force mechanisms to unpin it.

Signed-off-by: Christoph Hellwig 
Reported-by: Stefan Priebe 
Tested-by: Stefan Priebe 
Reviewed-by: Dave Chinner 
Signed-off-by: Alex Elder