MD: Memory leak when flush bio size is zero

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>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 1fa7f1b1d98a..fc488cb30a94 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -452,10 +452,11 @@ static void md_end_flush(struct bio *fbio)
         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);
                 }
@@ -509,10 +510,11 @@ void md_flush_request(struct mddev *mddev, struct bio *bio)
         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);
                 }