diff options
| author | Ming Lei <ming.lei@canonical.com> | 2016-04-15 18:51:28 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-05-04 14:48:39 -0700 |
| commit | 9fed24fe30c1217c640d2b38403034c2c7fdce12 (patch) | |
| tree | 989f5fee7b0d731b13b5f4bc31042a045c6ffc21 /drivers/block | |
| parent | 5b616a05de88d4be0136156a26fae9da855939f6 (diff) | |
block: loop: fix filesystem corruption in case of aio/dio
commit a7297a6a3a3322b054592e8e988981d2f5f29cc4 upstream.
Starting from commit e36f620428(block: split bios to max possible length),
block core starts to split bio in the middle of bvec.
Unfortunately loop dio/aio doesn't consider this situation, and
always treat 'iter.iov_offset' as zero. Then filesystem corruption
is observed.
This patch figures out the offset of the base bvevc via
'bio->bi_iter.bi_bvec_done' and fixes the issue by passing the offset
to iov iterator.
Fixes: e36f6204288088f (block: split bios to max possible length)
Cc: Keith Busch <keith.busch@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/loop.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 423f4ca7d712..80cf8add46ff 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -488,6 +488,12 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, bvec = __bvec_iter_bvec(bio->bi_io_vec, bio->bi_iter); iov_iter_bvec(&iter, ITER_BVEC | rw, bvec, bio_segments(bio), blk_rq_bytes(cmd->rq)); + /* + * This bio may be started from the middle of the 'bvec' + * because of bio splitting, so offset from the bvec must + * be passed to iov iterator + */ + iter.iov_offset = bio->bi_iter.bi_bvec_done; cmd->iocb.ki_pos = pos; cmd->iocb.ki_filp = file; |