scsi: lpfc: Fix validation of bsg reply lengths

There are a couple of code areas which validate sufficient reply buffer
length, but the checks are using the request elements rather than the reply
elements.

Rework to validate using the reply structures.

Link: https://lore.kernel.org/r/20200803210229.23063-7-jsmart2021@gmail.com
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/lpfc/lpfc_bsg.c

@@ -2494,13 +2494,12 @@ lpfc_sli4_bsg_link_diag_test(struct bsg_job *job)
 	diag_status_reply = (struct diag_status *)
 			    bsg_reply->reply_data.vendor_reply.vendor_rsp;
 
-	if (job->reply_len <
-	    sizeof(struct fc_bsg_request) + sizeof(struct diag_status)) {
+	if (job->reply_len < sizeof(*bsg_reply) + sizeof(*diag_status_reply)) {
 		lpfc_printf_log(phba, KERN_WARNING, LOG_LIBDFC,
 				"3012 Received Run link diag test reply "
 				"below minimum size (%d): reply_len:%d\n",
-				(int)(sizeof(struct fc_bsg_request) +
-				sizeof(struct diag_status)),
+				(int)(sizeof(*bsg_reply) +
+				sizeof(*diag_status_reply)),
 				job->reply_len);
 		rc = -EINVAL;
 		goto job_error;
@@ -3418,8 +3417,7 @@ lpfc_bsg_get_dfc_rev(struct bsg_job *job)
 	event_reply = (struct get_mgmt_rev_reply *)
 		bsg_reply->reply_data.vendor_reply.vendor_rsp;
 
-	if (job->reply_len <
-	    sizeof(struct fc_bsg_request) + sizeof(struct get_mgmt_rev_reply)) {
+	if (job->reply_len < sizeof(*bsg_reply) + sizeof(*event_reply)) {
 		lpfc_printf_log(phba, KERN_WARNING, LOG_LIBDFC,
 				"2741 Received GET_DFC_REV reply below "
 				"minimum size\n");
@@ -5202,8 +5200,8 @@ lpfc_menlo_cmd(struct bsg_job *job)
 		goto no_dd_data;
 	}
 
-	if (job->reply_len <
-	    sizeof(struct fc_bsg_request) + sizeof(struct menlo_response)) {
+	if (job->reply_len < sizeof(*bsg_reply) +
+				sizeof(struct menlo_response)) {
 		lpfc_printf_log(phba, KERN_WARNING, LOG_LIBDFC,
 				"2785 Received MENLO_CMD reply below "
 				"minimum size\n");
@@ -5359,9 +5357,7 @@ lpfc_forced_link_speed(struct bsg_job *job)
 	forced_reply = (struct forced_link_speed_support_reply *)
 		bsg_reply->reply_data.vendor_reply.vendor_rsp;
 
-	if (job->reply_len <
-	    sizeof(struct fc_bsg_request) +
-	    sizeof(struct forced_link_speed_support_reply)) {
+	if (job->reply_len < sizeof(*bsg_reply) + sizeof(*forced_reply)) {
 		lpfc_printf_log(phba, KERN_WARNING, LOG_LIBDFC,
 				"0049 Received FORCED_LINK_SPEED reply below "
 				"minimum size\n");
@@ -5715,8 +5711,7 @@ lpfc_get_trunk_info(struct bsg_job *job)
 	event_reply = (struct lpfc_trunk_info *)
 		bsg_reply->reply_data.vendor_reply.vendor_rsp;
 
-	if (job->reply_len <
-	    sizeof(struct fc_bsg_request) + sizeof(struct lpfc_trunk_info)) {
+	if (job->reply_len < sizeof(*bsg_reply) + sizeof(*event_reply)) {
 		lpfc_printf_log(phba, KERN_WARNING, LOG_LIBDFC,
 				"2728 Received GET TRUNK _INFO reply below "
 				"minimum size\n");