[PATCH] memstick: ms_block: destroy io_queue workqueue on removal

[Yifei Gao <gyf161023@gmail.com>]

msb_init_disk() creates the per-card ordered workqueue msb->io_queue with
alloc_ordered_workqueue(). It is torn down with destroy_workqueue() only
on the init error path; msb_remove() never destroys it. msb_stop() merely
flushes the queue, and neither msb_data_clear() nor put_disk() free it. As
a result every card insert/remove cycle leaks the workqueue and its
kworker, exhausting kernel memory over repeated cycles.

Destroy the workqueue in msb_remove() after the disk has been removed and
the queue drained.

Fixes: 0ab30494bc4f ("memstick: add support for legacy memorysticks")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Yifei Gao <gyf161023@gmail.com>
---
 drivers/memstick/core/ms_block.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/memstick/core/ms_block.c b/drivers/memstick/core/ms_block.c
index ce33907bfc24..65154e569a9e 100644
--- a/drivers/memstick/core/ms_block.c
+++ b/drivers/memstick/core/ms_block.c
@@ -2204,6 +2204,8 @@ static void msb_remove(struct memstick_dev *card)
 	msb_data_clear(msb);
 	mutex_unlock(&msb_disk_lock);
 
+	destroy_workqueue(msb->io_queue);
+
 	put_disk(msb->disk);
 	memstick_set_drvdata(card, NULL);
 }
-- 
2.43.0