From 9c3034968ed0feeaf72e5b549b19c7767a1a04f2 Mon Sep 17 00:00:00 2001 From: Justin Tee Date: Fri, 8 Sep 2023 14:18:52 -0700 Subject: [PATCH] scsi: lpfc: Early return after marking final NLP_DROPPED flag in dev_loss_tmo When a dev_loss_tmo event occurs, an ndlp lock is taken before checking nlp_flag for NLP_DROPPED. There is an attempt to restore the ndlp lock when exiting the if statement, but the nlp_put kref could be the final decrement causing a use-after-free memory access on a released ndlp object. Instead of trying to reacquire the ndlp lock after checking nlp_flag, just return after calling nlp_put. Signed-off-by: Justin Tee Link: https://lore.kernel.org/r/20230908211852.37576-1-justintee8345@gmail.com Reviewed-by: "Ewan D. Milne" Signed-off-by: Martin K. Petersen --- drivers/scsi/lpfc/lpfc_hbadisc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c index 51afb60859ebf..674dd07aae72a 100644 --- a/drivers/scsi/lpfc/lpfc_hbadisc.c +++ b/drivers/scsi/lpfc/lpfc_hbadisc.c @@ -203,7 +203,7 @@ lpfc_dev_loss_tmo_callbk(struct fc_rport *rport) ndlp->nlp_flag |= NLP_DROPPED; spin_unlock_irqrestore(&ndlp->lock, iflags); lpfc_nlp_put(ndlp); - spin_lock_irqsave(&ndlp->lock, iflags); + return; } spin_unlock_irqrestore(&ndlp->lock, iflags); -- 2.30.2