From: Colin Ian King <colin.king@canonical.com>
Date: Wed, 18 Nov 2020 13:13:45 +0000
Subject: scsi: lpfc: Fix pointer defereference before it is null checked issue
Patch-mainline: v5.11-rc1
Git-commit: 1e7dddb2e76a593627643c42f9bf57e5c0078f06
References: bsc#1164780

There is a null check on pointer lpfc_cmd after the pointer has been
dereferenced when pointers rdata and ndlp are initialized at the start of
the function. Fix this by only assigning rdata and ndlp after the pointer
lpfc_cmd has been null checked.

Link: https://lore.kernel.org/r/20201118131345.460631-1-colin.king@canonical.com
Fixes: 96e209be6ecb ("scsi: lpfc: Convert SCSI I/O completions to SLI-3 and SLI-4 handlers")
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Addresses-Coverity: ("Dereference before null check")
Acked-by: Daniel Wagner <dwagner@suse.de>
---
 drivers/scsi/lpfc/lpfc_scsi.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -4022,8 +4022,8 @@ lpfc_fcp_io_cmd_wqe_cmpl(struct lpfc_hba
 	struct lpfc_io_buf *lpfc_cmd =
 		(struct lpfc_io_buf *)pwqeIn->context1;
 	struct lpfc_vport *vport = pwqeIn->vport;
-	struct lpfc_rport_data *rdata = lpfc_cmd->rdata;
-	struct lpfc_nodelist *ndlp = rdata->pnode;
+	struct lpfc_rport_data *rdata;
+	struct lpfc_nodelist *ndlp;
 	struct scsi_cmnd *cmd;
 	unsigned long flags;
 	struct lpfc_fast_path_event *fast_path_evt;
@@ -4040,6 +4040,9 @@ lpfc_fcp_io_cmd_wqe_cmpl(struct lpfc_hba
 		return;
 	}
 
+	rdata = lpfc_cmd->rdata;
+	ndlp = rdata->pnode;
+
 	if (bf_get(lpfc_wcqe_c_xb, wcqe)) {
 		/* TOREMOVE - currently this flag is checked during
 		 * the release of lpfc_iocbq. Remove once we move