[PATCH 4.19 62/79] scsi: mpt3sas: Fix use-after-free warning

Greg Kroah-Hartman posted 79 patches 2 years, 11 months ago
[PATCH 4.19 62/79] scsi: mpt3sas: Fix use-after-free warning
Posted by Greg Kroah-Hartman 2 years, 11 months ago
From: Sreekanth Reddy <sreekanth.reddy@broadcom.com>

commit 991df3dd5144f2e6b1c38b8d20ed3d4d21e20b34 upstream.

Fix the following use-after-free warning which is observed during
controller reset:

refcount_t: underflow; use-after-free.
WARNING: CPU: 23 PID: 5399 at lib/refcount.c:28 refcount_warn_saturate+0xa6/0xf0

Link: https://lore.kernel.org/r/20220906134908.1039-2-sreekanth.reddy@broadcom.com
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/scsi/mpt3sas/mpt3sas_scsih.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -3215,6 +3215,7 @@ static struct fw_event_work *dequeue_nex
 		fw_event = list_first_entry(&ioc->fw_event_list,
 				struct fw_event_work, list);
 		list_del_init(&fw_event->list);
+		fw_event_work_put(fw_event);
 	}
 	spin_unlock_irqrestore(&ioc->fw_event_lock, flags);
 
@@ -3249,7 +3250,6 @@ _scsih_fw_event_cleanup_queue(struct MPT
 		if (cancel_work_sync(&fw_event->work))
 			fw_event_work_put(fw_event);
 
-		fw_event_work_put(fw_event);
 	}
 }