brd: Refuse improperly aligned discard requests

Currently when improperly aligned discard request is submitted, we just
silently discard more / less data which results in filesystem corruption
in some cases. Refuse such misaligned requests.

Signed-off-by: Jan Kara <jack@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Jan Kara 2015-11-04 17:13:39 +01:00 committed by Jens Axboe
parent c5a37883f4
commit 2dbe549576

View file

@ -337,6 +337,9 @@ static blk_qc_t brd_make_request(struct request_queue *q, struct bio *bio)
goto io_error;
if (unlikely(bio->bi_rw & REQ_DISCARD)) {
if (sector & ((PAGE_SIZE >> SECTOR_SHIFT) - 1) ||
bio->bi_iter.bi_size & PAGE_MASK)
goto io_error;
discard_from_brd(brd, sector, bio->bi_iter.bi_size);
goto out;
}