[PATCH AUTOSEL 4.14 6/8] scsi: mpt3sas: Fix use-after-free warning

[Sasha Levin]

From: Sreekanth Reddy <sreekanth.reddy@xxxxxxxxxxxx>

[ Upstream commit 991df3dd5144f2e6b1c38b8d20ed3d4d21e20b34 ]

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@xxxxxxxxxxxx
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@xxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/scsi/mpt3sas/mpt3sas_scsih.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
index 79c5a193308f4..8fb7491c5bc02 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -2804,6 +2804,7 @@ static struct fw_event_work *dequeue_next_fw_event(struct MPT3SAS_ADAPTER *ioc)
 		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);
 
@@ -2840,7 +2841,6 @@ _scsih_fw_event_cleanup_queue(struct MPT3SAS_ADAPTER *ioc)
 		if (cancel_work_sync(&fw_event->work))
 			fw_event_work_put(fw_event);
 
-		fw_event_work_put(fw_event);
 	}
 }
 
-- 
2.35.1