sfc: Support variable-length response to MCDI GET_BOARD_CFG

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

2 files changed, 6 insertions, 3 deletions

diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c
index 578e5f72aabe..e855f4cddb4e 100644
--- a/drivers/net/ethernet/sfc/mcdi.c
+++ b/drivers/net/ethernet/sfc/mcdi.c
@@ -683,12 +683,14 @@ int efx_mcdi_get_board_cfg(struct efx_nic *efx, u8 *mac_address,
         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;
                 }
         }
diff --git a/drivers/net/ethernet/sfc/mtd.c b/drivers/net/ethernet/sfc/mtd.c
index 758148379b0e..8f4604d5d642 100644
--- a/drivers/net/ethernet/sfc/mtd.c
+++ b/drivers/net/ethernet/sfc/mtd.c
@@ -627,7 +627,8 @@ static int siena_mtd_get_fw_subtypes(struct efx_nic *efx,
                                      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);