Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
        if (mac_address)
                memcpy(mac_address, outbuf + offset, ETH_ALEN);
        if (fw_subtype_list) {
+               /* Byte-swap and truncate or zero-pad as necessary */
                offset = MC_CMD_GET_BOARD_CFG_OUT_FW_SUBTYPE_LIST_OFST;
                for (i = 0;
-                    i < MC_CMD_GET_BOARD_CFG_OUT_FW_SUBTYPE_LIST_MINNUM;
+                    i < MC_CMD_GET_BOARD_CFG_OUT_FW_SUBTYPE_LIST_MAXNUM;
                     i++) {
                        fw_subtype_list[i] =
-                               le16_to_cpup((__le16 *)(outbuf + offset));
+                               (offset + 2 <= outlen) ?
+                               le16_to_cpup((__le16 *)(outbuf + offset)) : 0;
                        offset += 2;
                }
        }
 
                                     struct efx_mtd *efx_mtd)
 {
        struct efx_mtd_partition *part;
-       uint16_t fw_subtype_list[MC_CMD_GET_BOARD_CFG_OUT_FW_SUBTYPE_LIST_MINNUM];
+       uint16_t fw_subtype_list[
+               MC_CMD_GET_BOARD_CFG_OUT_FW_SUBTYPE_LIST_MAXNUM];
        int rc;
 
        rc = efx_mcdi_get_board_cfg(efx, NULL, fw_subtype_list, NULL);