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  1. 07 3月, 2011 2 次提交
  3. 19 10月, 2010 1 次提交
  5. 24 8月, 2010 1 次提交
    • D
      xfs: fix untrusted inode number lookup · 4536f2ad
      由 Dave Chinner 提交于 
      Commit 7124fe0a ("xfs: validate untrusted inode
numbers during lookup") changes the inode lookup code to do btree lookups for
untrusted inode numbers. This change made an invalid assumption about the
alignment of inodes and hence incorrectly calculated the first inode in the
cluster. As a result, some inode numbers were being incorrectly considered
invalid when they were actually valid.

The issue was not picked up by the xfstests suite because it always runs fsr
and dump (the two utilities that utilise the bulkstat interface) on cache hot
inodes and hence the lookup code in the cold cache path was not sufficiently
exercised to uncover this intermittent problem.

Fix the issue by relaxing the btree lookup criteria and then checking if the
record returned contains the inode number we are lookup for. If it we get an
incorrect record, then the inode number is invalid.

Cc: <stable@kernel.org>
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      4536f2ad
  7. 27 7月, 2010 2 次提交
  9. 24 6月, 2010 3 次提交
    • D
      xfs: remove block number from inode lookup code · 7b6259e7
      由 Dave Chinner 提交于 
      The block number comes from bulkstat based inode lookups to shortcut
the mapping calculations. We ar enot able to trust anything from
bulkstat, so drop the block number as well so that the correct
lookups and mappings are always done.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      7b6259e7
    • D
      xfs: rename XFS_IGET_BULKSTAT to XFS_IGET_UNTRUSTED · 1920779e
      由 Dave Chinner 提交于 
      Inode numbers may come from somewhere external to the filesystem
(e.g. file handles, bulkstat information) and so are inherently
untrusted. Rename the flag we use for these lookups to make it
obvious we are doing a lookup of an untrusted inode number and need
to verify it completely before trying to read it from disk.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      1920779e
    • D
      xfs: validate untrusted inode numbers during lookup · 7124fe0a
      由 Dave Chinner 提交于 
      When we decode a handle or do a bulkstat lookup, we are using an
inode number we cannot trust to be valid. If we are deleting inode
chunks from disk (default noikeep mode), then we cannot trust the on
disk inode buffer for any given inode number to correctly reflect
whether the inode has been unlinked as the di_mode nor the
generation number may have been updated on disk.

This is due to the fact that when we delete an inode chunk, we do
not write the clusters back to disk when they are removed - instead
we mark them stale to avoid them being written back potentially over
the top of something that has been subsequently allocated at that
location. The result is that we can have locations of disk that look
like they contain valid inodes but in reality do not. Hence we
cannot simply convert the inode number to a block number and read
the location from disk to determine if the inode is valid or not.

As a result, and XFS_IGET_BULKSTAT lookup needs to actually look the
inode up in the inode allocation btree to determine if the inode
number is valid or not.

It should be noted even on ikeep filesystems, there is the
possibility that blocks on disk may look like valid inode clusters.
e.g. if there are filesystem images hosted on the filesystem. Hence
even for ikeep filesystems we really need to validate that the inode
number is valid before issuing the inode buffer read.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
      7124fe0a
  11. 22 1月, 2010 1 次提交
  13. 16 1月, 2010 2 次提交
    • D
      xfs: Replace per-ag array with a radix tree · 1c1c6ebc
      由 Dave Chinner 提交于 
      The use of an array for the per-ag structures requires reallocation
of the array when growing the filesystem. This requires locking
access to the array to avoid use after free situations, and the
locking is difficult to get right. To avoid needing to reallocate an
array, change the per-ag structures to an allocated object per ag
and index them using a tree structure.

The AGs are always densely indexed (hence the use of an array), but
the number supported is 2^32 and lookups tend to be random and hence
indexing needs to scale. A simple choice is a radix tree - it works
well with this sort of index.  This change also removes another
large contiguous allocation from the mount/growfs path in XFS.

The growing process now needs to change to only initialise the new
AGs required for the extra space, and as such only needs to
exclusively lock the tree for inserts. The rest of the code only
needs to lock the tree while doing lookups, and hence this will
remove all the deadlocks that currently occur on the m_perag_lock as
it is now an innermost lock. The lock is also changed to a spinlock
from a read/write lock as the hold time is now extremely short.

To complete the picture, the per-ag structures will need to be
reference counted to ensure that we don't free/modify them while
they are still in use.  This will be done in subsequent patch.
Signed-off-by: NDave Chinner <david@fromorbit.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAlex Elder <aelder@sgi.com>
      1c1c6ebc
    • D
      xfs: convert remaining direct references to m_perag · 44b56e0a
      由 Dave Chinner 提交于 
      Convert the remaining direct lookups of the per ag structures to use
get/put accesses. Ensure that the loops across AGs and prior users
of the interface balance gets and puts correctly.
Signed-off-by: NDave Chinner <david@fromorbit.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAlex Elder <aelder@sgi.com>
      44b56e0a
  15. 12 12月, 2009 1 次提交
  17. 30 10月, 2009 1 次提交
    • E
      xfs: free temporary cursor in xfs_dialloc · 3b826386
      由 Eric Sandeen 提交于 
      Commit bd169565 seems
to have a slight regression where this code path:

    if (!--searchdistance) {
        /*
         * Not in range - save last search
         * location and allocate a new inode
         */
        ...
        goto newino;
    }

doesn't free the temporary cursor (tcur) that got dup'd in
this function.

This leaks an item in the xfs_btree_cur zone, and it's caught
on module unload:

===========================================================
BUG xfs_btree_cur: Objects remaining on kmem_cache_close()
-----------------------------------------------------------

It seems like maybe a single free at the end of the function might
be cleaner, but for now put a del_cursor right in this code block
similar to the handling in the rest of the function.
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
      3b826386
  19. 02 9月, 2009 8 次提交
  21. 29 3月, 2009 1 次提交
  23. 09 2月, 2009 1 次提交
  25. 19 1月, 2009 1 次提交
  27. 16 1月, 2009 1 次提交
  29. 01 12月, 2008 8 次提交
  31. 30 10月, 2008 6 次提交