Skip to content
  1. Dec 03, 2019
    • Omar Sandoval's avatar
      xfs: don't check for AG deadlock for realtime files in bunmapi · 69ffe596
      Omar Sandoval authored 
      Commit 5b094d6d ("xfs: fix multi-AG deadlock in xfs_bunmapi") added
a check in __xfs_bunmapi() to stop early if we would touch multiple AGs
in the wrong order. However, this check isn't applicable for realtime
files. In most cases, it just makes us do unnecessary commits. However,
without the fix from the previous commit ("xfs: fix realtime file data
space leak"), if the last and second-to-last extents also happen to have
different "AG numbers", then the break actually causes __xfs_bunmapi()
to return without making any progress, which sends
xfs_itruncate_extents_flags() into an infinite loop.

Fixes: 5b094d6d

 ("xfs: fix multi-AG deadlock in xfs_bunmapi")
Signed-off-by: default avatarOmar Sandoval <osandov@fb.com>
Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
      69ffe596
    • Omar Sandoval's avatar
      xfs: fix realtime file data space leak · 0c4da70c
      Omar Sandoval authored 
      

Realtime files in XFS allocate extents in rextsize units. However, the
written/unwritten state of those extents is still tracked in blocksize
units. Therefore, a realtime file can be split up into written and
unwritten extents that are not necessarily aligned to the realtime
extent size. __xfs_bunmapi() has some logic to handle these various
corner cases. Consider how it handles the following case:

1. The last extent is unwritten.
2. The last extent is smaller than the realtime extent size.
3. startblock of the last extent is not aligned to the realtime extent
   size, but startblock + blockcount is.

In this case, __xfs_bunmapi() calls xfs_bmap_add_extent_unwritten_real()
to set the second-to-last extent to unwritten. This should merge the
last and second-to-last extents, so __xfs_bunmapi() moves on to the
second-to-last extent.

However, if the size of the last and second-to-last extents combined is
greater than MAXEXTLEN, xfs_bmap_add_extent_unwritten_real() does not
merge the two extents. When that happens, __xfs_bunmapi() skips past the
last extent without unmapping it, thus leaking the space.

Fix it by only unwriting the minimum amount needed to align the last
extent to the realtime extent size, which is guaranteed to merge with
the last extent.

Signed-off-by: default avatarOmar Sandoval <osandov@fb.com>
Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
      0c4da70c
  3. Nov 28, 2019
  5. Nov 23, 2019
  7. Nov 19, 2019
  9. Nov 16, 2019
    • Brian Foster's avatar
      xfs: fix attr leaf header freemap.size underflow · 2a2b5932
      Brian Foster authored 
      

The leaf format xattr addition helper xfs_attr3_leaf_add_work()
adjusts the block freemap in a couple places. The first update drops
the size of the freemap that the caller had already selected to
place the xattr name/value data. Before the function returns, it
also checks whether the entries array has encroached on a freemap
range by virtue of the new entry addition. This is necessary because
the entries array grows from the start of the block (but end of the
block header) towards the end of the block while the name/value data
grows from the end of the block in the opposite direction. If the
associated freemap is already empty, however, size is zero and the
subtraction underflows the field and causes corruption.

This is reproduced rarely by generic/070. The observed behavior is
that a smaller sized freemap is aligned to the end of the entries
list, several subsequent xattr additions land in larger freemaps and
the entries list expands into the smaller freemap until it is fully
consumed and then underflows. Note that it is not otherwise a
corruption for the entries array to consume an empty freemap because
the nameval list (i.e. the firstused pointer in the xattr header)
starts beyond the end of the corrupted freemap.

Update the freemap size modification to account for the fact that
the freemap entry can be empty and thus stale.

Signed-off-by: default avatarBrian Foster <bfoster@redhat.com>
Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
      2a2b5932
    • Darrick J. Wong's avatar
      xfs: fix some memory leaks in log recovery · 050552cb
      Darrick J. Wong authored 
      

Fix a few places where we xlog_alloc_buffer a buffer, hit an error, and
then bail out without freeing the buffer.

Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarBrian Foster <bfoster@redhat.com>
      050552cb
  11. Nov 14, 2019
  13. Nov 13, 2019
    • Darrick J. Wong's avatar
      xfs: kill the XFS_WANT_CORRUPT_* macros · f9e03706
      Darrick J. Wong authored 
      

The XFS_WANT_CORRUPT_* macros conceal subtle side effects such as the
creation of local variables and redirections of the code flow.  This is
pretty ugly, so replace them with explicit XFS_IS_CORRUPT tests that
remove both of those ugly points.  The change was performed with the
following coccinelle script:

@@
expression mp, test;
identifier label;
@@

- XFS_WANT_CORRUPTED_GOTO(mp, test, label);
+ if (XFS_IS_CORRUPT(mp, !test)) { error = -EFSCORRUPTED; goto label; }

@@
expression mp, test;
@@

- XFS_WANT_CORRUPTED_RETURN(mp, test);
+ if (XFS_IS_CORRUPT(mp, !test)) return -EFSCORRUPTED;

@@
expression mp, lval, rval;
@@

- XFS_IS_CORRUPT(mp, !(lval == rval))
+ XFS_IS_CORRUPT(mp, lval != rval)

@@
expression mp, e1, e2;
@@

- XFS_IS_CORRUPT(mp, !(e1 && e2))
+ XFS_IS_CORRUPT(mp, !e1 || !e2)

@@
expression e1, e2;
@@

- !(e1 == e2)
+ e1 != e2

@@
expression e1, e2, e3, e4, e5, e6;
@@

- !(e1 == e2 && e3 == e4) || e5 != e6
+ e1 != e2 || e3 != e4 || e5 != e6

@@
expression e1, e2, e3, e4, e5, e6;
@@

- !(e1 == e2 || (e3 <= e4 && e5 <= e6))
+ e1 != e2 && (e3 > e4 || e5 > e6)

@@
expression mp, e1, e2;
@@

- XFS_IS_CORRUPT(mp, !(e1 <= e2))
+ XFS_IS_CORRUPT(mp, e1 > e2)

@@
expression mp, e1, e2;
@@

- XFS_IS_CORRUPT(mp, !(e1 < e2))
+ XFS_IS_CORRUPT(mp, e1 >= e2)

@@
expression mp, e1;
@@

- XFS_IS_CORRUPT(mp, !!e1)
+ XFS_IS_CORRUPT(mp, e1)

@@
expression mp, e1, e2;
@@

- XFS_IS_CORRUPT(mp, !(e1 || e2))
+ XFS_IS_CORRUPT(mp, !e1 && !e2)

@@
expression mp, e1, e2, e3, e4;
@@

- XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 == e4))
+ XFS_IS_CORRUPT(mp, e1 != e2 && e3 != e4)

@@
expression mp, e1, e2, e3, e4;
@@

- XFS_IS_CORRUPT(mp, !(e1 <= e2) || !(e3 >= e4))
+ XFS_IS_CORRUPT(mp, e1 > e2 || e3 < e4)

@@
expression mp, e1, e2, e3, e4;
@@

- XFS_IS_CORRUPT(mp, !(e1 == e2) && !(e3 <= e4))
+ XFS_IS_CORRUPT(mp, e1 != e2 && e3 > e4)

Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      f9e03706
    • Darrick J. Wong's avatar
      xfs: add a XFS_IS_CORRUPT macro · 1ec28615
      Darrick J. Wong authored 
      

Add a new macro, XFS_IS_CORRUPT, which we will use to integrate some
corruption reporting when the corruption test expression is true.  This
will be used in the next patch to remove the ugly XFS_WANT_CORRUPT*
macros.

Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      1ec28615
  15. Nov 12, 2019