From 30f667466622ee0cb4a90477711813e68b9f5dd5 Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bart.vanassche@sandisk.com>
Date: Tue, 15 Dec 2015 16:38:22 +0100
Subject: [PATCH] brd: Fix discard request processing
Avoid that discard requests with size => PAGE_SIZE fail with
-EIO. Refuse discard requests if the discard size is not a
multiple of the page size.
Fixes: cccb0842a28c ("brd: Refuse improperly aligned discard requests")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Jan Kara <jack@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Robert Elliot <elliott@hp.com>
Cc: stable <stable@vger.kernel.org> # v4.4+
Signed-off-by: Jens Axboe <axboe@fb.com>
---
drivers/block/brd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index cb27190e9f395..f7ecc287d733b 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -341,7 +341,7 @@ static blk_qc_t brd_make_request(struct request_queue *q, struct bio *bio)
if (unlikely(bio->bi_rw & REQ_DISCARD)) {
if (sector & ((PAGE_SIZE >> SECTOR_SHIFT) - 1) ||
- bio->bi_iter.bi_size & PAGE_MASK)
+ bio->bi_iter.bi_size & ~PAGE_MASK)
goto io_error;
discard_from_brd(brd, sector, bio->bi_iter.bi_size);
goto out;
--
2.39.5