aboutsummaryrefslogtreecommitdiff
path: root/drivers/md/dm.c
diff options
context:
space:
mode:
authorMike Snitzer <snitzer@redhat.com>2016-02-21 19:09:22 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-03-03 15:07:14 -0800
commit5c6f66674274958e0ea2d2d6c7a905e4ea73881e (patch)
tree77e9e0b28705c7e89ef853fe65a21ae0b3bc35b6 /drivers/md/dm.c
parent1264fbd72f85446aa75bc3895e13589c1ed2c6df (diff)
dm: fix dm_rq_target_io leak on faults with .request_fn DM w/ blk-mq paths
commit 4328daa2e79ed904a42ce00a9f38b9c36b44b21a upstream. Using request-based DM mpath configured with the following stacking (.request_fn DM mpath ontop of scsi-mq paths): echo Y > /sys/module/scsi_mod/parameters/use_blk_mq echo N > /sys/module/dm_mod/parameters/use_blk_mq 'struct dm_rq_target_io' would leak if a request is requeued before a blk-mq clone is allocated (or fails to allocate). free_rq_tio() wasn't being called. kmemleak reported: unreferenced object 0xffff8800b90b98c0 (size 112): comm "kworker/7:1H", pid 5692, jiffies 4295056109 (age 78.589s) hex dump (first 32 bytes): 00 d0 5c 2c 03 88 ff ff 40 00 bf 01 00 c9 ff ff ..\,....@....... e0 d9 b1 34 00 88 ff ff 00 00 00 00 00 00 00 00 ...4............ backtrace: [<ffffffff81672b6e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff811dbb63>] kmem_cache_alloc+0xc3/0x1e0 [<ffffffff8117eae5>] mempool_alloc_slab+0x15/0x20 [<ffffffff8117ec1e>] mempool_alloc+0x6e/0x170 [<ffffffffa00029ac>] dm_old_prep_fn+0x3c/0x180 [dm_mod] [<ffffffff812fbd78>] blk_peek_request+0x168/0x290 [<ffffffffa0003e62>] dm_request_fn+0xb2/0x1b0 [dm_mod] [<ffffffff812f66e3>] __blk_run_queue+0x33/0x40 [<ffffffff812f9585>] blk_delay_work+0x25/0x40 [<ffffffff81096fff>] process_one_work+0x14f/0x3d0 [<ffffffff81097715>] worker_thread+0x125/0x4b0 [<ffffffff8109ce88>] kthread+0xd8/0xf0 [<ffffffff8167cb8f>] ret_from_fork+0x3f/0x70 [<ffffffffffffffff>] 0xffffffffffffffff crash> struct -o dm_rq_target_io struct dm_rq_target_io { ... } SIZE: 112 Fixes: e5863d9ad7 ("dm: allocate requests in target when stacking on blk-mq devices") Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/md/dm.c')
-rw-r--r--drivers/md/dm.c2
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 5df40480228b..dd834927bc66 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1191,6 +1191,8 @@ static void dm_unprep_request(struct request *rq)
if (clone)
free_rq_clone(clone);
+ else if (!tio->md->queue->mq_ops)
+ free_rq_tio(tio);
}
/*