diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 67d2663b3974..17a972734ba7 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -14604,8 +14604,11 @@ static void tg3_read_vpd(struct tg3 *tp)
 		if (j + len > block_end)
 			goto partno;
 
-		memcpy(tp->fw_ver, &vpd_data[j], len);
-		strncat(tp->fw_ver, " bc ", vpdlen - len - 1);
+		if (len >= sizeof(tp->fw_ver))
+			len = sizeof(tp->fw_ver) - 1;
+		memset(tp->fw_ver, 0, sizeof(tp->fw_ver));
+		snprintf(tp->fw_ver, sizeof(tp->fw_ver), "%.*s bc ", len,
+			 &vpd_data[j]);
 	}
 
 partno: