In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields.
Add struct_group() to mark region of struct stats_reply_data that should be initialized, which can now be done in a single memset() call.
Signed-off-by: Kees Cook keescook@chromium.org --- net/ethtool/stats.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-)
diff --git a/net/ethtool/stats.c b/net/ethtool/stats.c index ec07f5765e03..a20e0a24ff61 100644 --- a/net/ethtool/stats.c +++ b/net/ethtool/stats.c @@ -14,10 +14,12 @@ struct stats_req_info {
struct stats_reply_data { struct ethnl_reply_data base; - struct ethtool_eth_phy_stats phy_stats; - struct ethtool_eth_mac_stats mac_stats; - struct ethtool_eth_ctrl_stats ctrl_stats; - struct ethtool_rmon_stats rmon_stats; + struct_group(stats, + struct ethtool_eth_phy_stats phy_stats; + struct ethtool_eth_mac_stats mac_stats; + struct ethtool_eth_ctrl_stats ctrl_stats; + struct ethtool_rmon_stats rmon_stats; + ); const struct ethtool_rmon_hist_range *rmon_ranges; };
@@ -117,10 +119,7 @@ static int stats_prepare_data(const struct ethnl_req_info *req_base, /* Mark all stats as unset (see ETHTOOL_STAT_NOT_SET) to prevent them * from being reported to user space in case driver did not set them. */ - memset(&data->phy_stats, 0xff, sizeof(data->phy_stats)); - memset(&data->mac_stats, 0xff, sizeof(data->mac_stats)); - memset(&data->ctrl_stats, 0xff, sizeof(data->ctrl_stats)); - memset(&data->rmon_stats, 0xff, sizeof(data->rmon_stats)); + memset(&data->stats, 0xff, sizeof(data->stats));
if (test_bit(ETHTOOL_STATS_ETH_PHY, req_info->stat_mask) && dev->ethtool_ops->get_eth_phy_stats)