diff options
| author | David Chinner <dgc@sgi.com> | 2006-09-28 11:06:03 +1000 |
|---|---|---|
| committer | Tim Shimmin <tes@sgi.com> | 2006-09-28 11:06:03 +1000 |
| commit | f273ab848b7cbc0088b0ac7457b3769e6566074e (patch) | |
| tree | 27f1b0ce7b056f77e7105284524cbdb658943ae5 /fs/xfs/xfs_vnodeops.c | |
| parent | 01106eae97b70399ce5a273a3cceb5246e8d9cc8 (diff) | |
[XFS] Really fix use after free in xfs_iunpin.
The previous attempts to fix the linux inode use-after-free in xfs_iunpin
simply made the problem harder to hit. We actually need complete exclusion
between xfs_reclaim and xfs_iunpin, as well as ensuring that the i_flags
are consistent during both of these functions. Introduce a new spinlock
for exclusion and the i_flags, and fix up xfs_iunpin to use igrab before
marking the inode dirty.
SGI-PV: 952967
SGI-Modid: xfs-linux-melb:xfs-kern:26964a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Diffstat (limited to 'fs/xfs/xfs_vnodeops.c')
| -rw-r--r-- | fs/xfs/xfs_vnodeops.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c index 1a6782eaf5d..061e2ffdd1d 100644 --- a/fs/xfs/xfs_vnodeops.c +++ b/fs/xfs/xfs_vnodeops.c @@ -3844,7 +3844,9 @@ xfs_reclaim( XFS_MOUNT_ILOCK(mp); vn_bhv_remove(VN_BHV_HEAD(vp), XFS_ITOBHV(ip)); list_add_tail(&ip->i_reclaim, &mp->m_del_inodes); + spin_lock(&ip->i_flags_lock); ip->i_flags |= XFS_IRECLAIMABLE; + spin_unlock(&ip->i_flags_lock); XFS_MOUNT_IUNLOCK(mp); } return 0; @@ -3869,8 +3871,10 @@ xfs_finish_reclaim( * us. */ write_lock(&ih->ih_lock); + spin_lock(&ip->i_flags_lock); if ((ip->i_flags & XFS_IRECLAIM) || (!(ip->i_flags & XFS_IRECLAIMABLE) && vp == NULL)) { + spin_unlock(&ip->i_flags_lock); write_unlock(&ih->ih_lock); if (locked) { xfs_ifunlock(ip); @@ -3879,6 +3883,7 @@ xfs_finish_reclaim( return 1; } ip->i_flags |= XFS_IRECLAIM; + spin_unlock(&ip->i_flags_lock); write_unlock(&ih->ih_lock); /* |