[PATCH 4.18 138/350] MD: Memory leak when flush bio size is zero

Greg Kroah-Hartman
2018-11-11T23:32:09Z

From: Xiao Ni <xni@redhat.com>

[ Upstream commit af9b926de9c5986ab009e64917de87c9758bab10 ]

flush_pool is leaked when flush bio size is zero

Fixes: 5a409b4f56d5 ("MD: fix lock contention for flush bios")
Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/md/md.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -455,10 +455,11 @@ static void md_end_flush(struct bio *fbi
rdev_dec_pending(rdev, mddev);

if (atomic_dec_and_test(&fi->flush_pending)) {
- if (bio->bi_iter.bi_size == 0)
+ if (bio->bi_iter.bi_size == 0) {
/* an empty barrier - all done */
bio_endio(bio);
- else {
+ mempool_free(fi, mddev->flush_pool);
+ } else {
INIT_WORK(&fi->flush_work, submit_flushes);
queue_work(md_wq, &fi->flush_work);
}
@@ -512,10 +513,11 @@ void md_flush_request(struct mddev *mdde
rcu_read_unlock();

if (atomic_dec_and_test(&fi->flush_pending)) {
- if (bio->bi_iter.bi_size == 0)
+ if (bio->bi_iter.bi_size == 0) {
/* an empty barrier - all done */
bio_endio(bio);
- else {
+ mempool_free(fi, mddev->flush_pool);
+ } else {
INIT_WORK(&fi->flush_work, submit_flushes);
queue_work(md_wq, &fi->flush_work);
}