diff options
author | Mikulas Patocka <mpatocka@redhat.com> | 2018-07-03 13:34:22 -0400 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2018-07-09 09:07:54 -0600 |
commit | b88aef36b87c9787a4db724923ec4f57dfd513f3 (patch) | |
tree | 9d493ac5c131c41f719877fb632493d99b6614e7 | |
parent | c137969bd4c5b2a67803d10518e3d60d3b13d0cb (diff) | |
download | linux-b88aef36b87c9787a4db724923ec4f57dfd513f3.tar.bz2 |
block: fix infinite loop if the device loses discard capability
If __blkdev_issue_discard is in progress and a device mapper device is
reloaded with a table that doesn't support discard,
q->limits.max_discard_sectors is set to zero. This results in infinite
loop in __blkdev_issue_discard.
This patch checks if max_discard_sectors is zero and aborts with
-EOPNOTSUPP.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Tested-by: Zdenek Kabelac <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | block/blk-lib.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/block/blk-lib.c b/block/blk-lib.c index 8faa70f26fcd..d1b9dd03da25 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -68,6 +68,8 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, */ req_sects = min_t(sector_t, nr_sects, q->limits.max_discard_sectors); + if (!req_sects) + goto fail; if (req_sects > UINT_MAX >> 9) req_sects = UINT_MAX >> 9; @@ -105,6 +107,14 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, *biop = bio; return 0; + +fail: + if (bio) { + submit_bio_wait(bio); + bio_put(bio); + } + *biop = NULL; + return -EOPNOTSUPP; } EXPORT_SYMBOL(__blkdev_issue_discard); |