bcache: destroy dc->writeback_write_wq if failed to create dc->writeback_thread

commit f54d801dda14942dbefa00541d10603015b7859c upstream.

Commit 9baf30972b55 ("bcache: fix for gc and write-back race") added a
new work queue dc->writeback_write_wq, but forgot to destroy it in the
error condition when creating dc->writeback_thread failed.

This patch destroys dc->writeback_write_wq if kthread_create() returns
error pointer to dc->writeback_thread, then a memory leak is avoided.

Fixes: 9baf30972b55 ("bcache: fix for gc and write-back race")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index df0f4e5a051a0dfd0ba55b89bbbf828951e388c4..e9ffcea1ca50478edc94ae55afb0ca3866d6650d 100644 (file)
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -834,6 +834,7 @@ int bch_cached_dev_writeback_start(struct cached_dev *dc)
                                              "bcache_writeback");
        if (IS_ERR(dc->writeback_thread)) {
                cached_dev_put(dc);
+               destroy_workqueue(dc->writeback_write_wq);
                return PTR_ERR(dc->writeback_thread);
        }
        dc->writeback_running = true;