From af6de8c60fe9433afa73cea6fcccdccd98ad3e5e Mon Sep 17 00:00:00 2001 From: "Ewan D. Milne" Date: Wed, 29 Jul 2020 19:10:11 -0400 Subject: [PATCH] scsi: lpfc: nvmet: Avoid hang / use-after-free again when destroying targetport We cannot wait on a completion object in the lpfc_nvme_targetport structure in the _destroy_targetport() code path because the NVMe/fc transport will free that structure immediately after the .targetport_delete() callback. This results in a use-after-free, and a crash if slub_debug=FZPU is enabled. An earlier fix put put the completion on the stack, but commit 2a0fb340fcc8 ("scsi: lpfc: Correct localport timeout duration error") subsequently changed the code to reference the completion through a pointer in the object rather than the local stack variable. Fix this by using the stack variable directly. Link: https://lore.kernel.org/r/20200729231011.13240-1-emilne@redhat.com Fixes: 2a0fb340fcc8 ("scsi: lpfc: Correct localport timeout duration error") Reviewed-by: James Smart Signed-off-by: Ewan D. Milne Signed-off-by: Martin K. Petersen --- drivers/scsi/lpfc/lpfc_nvmet.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/lpfc/lpfc_nvmet.c b/drivers/scsi/lpfc/lpfc_nvmet.c index a4430aeeb04a8..d4ade7cdb93a9 100644 --- a/drivers/scsi/lpfc/lpfc_nvmet.c +++ b/drivers/scsi/lpfc/lpfc_nvmet.c @@ -2110,7 +2110,7 @@ lpfc_nvmet_destroy_targetport(struct lpfc_hba *phba) } tgtp->tport_unreg_cmp = &tport_unreg_cmp; nvmet_fc_unregister_targetport(phba->targetport); - if (!wait_for_completion_timeout(tgtp->tport_unreg_cmp, + if (!wait_for_completion_timeout(&tport_unreg_cmp, msecs_to_jiffies(LPFC_NVMET_WAIT_TMO))) lpfc_printf_log(phba, KERN_ERR, LOG_TRACE_EVENT, "6179 Unreg targetport x%px timeout " -- 2.30.2