scsi: qedf: Check the validity of rjt frame before processing

This is reported by Klockwork.

Link: https://lore.kernel.org/r/20200807110656.19965-3-jhasan@marvell.comSigned-off-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Javed Hasan <jhasan@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qedf/qedf_els.c

@@ -883,6 +883,11 @@ static void qedf_rec_compl(struct qedf_els_cb_arg *cb_arg)
 	opcode = fc_frame_payload_op(fp);
 	if (opcode == ELS_LS_RJT) {
 		rjt = fc_frame_payload_get(fp, sizeof(*rjt));
+		if (!rjt) {
+			QEDF_ERR(&qedf->dbg_ctx, "payload get failed");
+			goto out_free_frame;
+		}
+
 		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
 		    "Received LS_RJT for REC: er_reason=0x%x, "
 		    "er_explan=0x%x.\n", rjt->er_reason, rjt->er_explan);