scsi: lpfc: Check devloss callbk done flag for potential stale NDLP ptrs

Should an rport remain in the NOTPRESENT state it is possible that
stgt_delete_work is scheduled after dev_loss_tmo_callbk.  In such cases,
dev_loss_tmo_callbk would have cleaned up the NDLP object resulting in
stale ndlp pointers in lpfc_terminate_rport_io().

Check for the DEVLOSS_CALLBK_DONE flag to know if dev_loss_tmo_callbk
has been called.  This is a more reliable way to avoid dereferencing
stale NDLP pointers.

Signed-off-by: Justin Tee <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Martin K. Petersen <[email protected]>

Author: Justin Tee

drivers/scsi/lpfc/lpfc_hbadisc.c

@@ -100,6 +100,12 @@ lpfc_rport_invalid(struct fc_rport *rport)
 		return -EINVAL;
 	}
 
+	if (rport->flags & FC_RPORT_DEVLOSS_CALLBK_DONE) {
+		pr_info("**** %s: devloss_callbk_done rport x%px SID x%x\n",
+			__func__, rport, rport->scsi_target_id);
+		return -EINVAL;
+	}
+
 	rdata = rport->dd_data;
 	if (!rdata) {
 		pr_err("**** %s: NULL dd_data on rport x%px SID x%x\n",