diff options
| author | Jan Kara <jack@suse.cz> | 2016-02-19 00:33:21 -0500 |
|---|---|---|
| committer | Luis Henriques <luis.henriques@canonical.com> | 2016-03-04 10:26:43 +0000 |
| commit | c0c009a095deb004ed422c10e02054e15ed4a340 (patch) | |
| tree | 453683077152790437f6b75b25c9d742d467d6a8 /kernel | |
| parent | 6d4048ac27fd3a641d368943ea6deb13de3e6051 (diff) | |
ext4: fix crashes in dioread_nolock mode
commit 74dae4278546b897eb81784fdfcce872ddd8b2b8 upstream.
Competing overwrite DIO in dioread_nolock mode will just overwrite
pointer to io_end in the inode. This may result in data corruption or
extent conversion happening from IO completion interrupt because we
don't properly set buffer_defer_completion() when unlocked DIO races
with locked DIO to unwritten extent.
Since unlocked DIO doesn't need io_end for anything, just avoid
allocating it and corrupting pointer from inode for locked DIO.
A cleaner fix would be to avoid these games with io_end pointer from the
inode but that requires more intrusive changes so we leave that for
later.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Diffstat (limited to 'kernel')
0 files changed, 0 insertions, 0 deletions