igb: Avoid memcpy() over-reading of ETH_SS_STATS

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally reading across neighboring array fields.

The memcpy() is copying the entire structure, not just the first array.
Adjust the source argument so the compiler can do appropriate bounds
checking.

Signed-off-by: Kees Cook <keescook@chromium.org>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c
index 636a1b1fb7e1d697f869677d845d58d6a3894bd3..17f5c003c3df156d8012ba7e841d8487241dfaf3 100644 (file)
--- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
+++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
@@ -2343,8 +2343,7 @@ static void igb_get_strings(struct net_device *netdev, u32 stringset, u8 *data)
 
        switch (stringset) {
        case ETH_SS_TEST:
-               memcpy(data, *igb_gstrings_test,
-                       IGB_TEST_LEN*ETH_GSTRING_LEN);
+               memcpy(data, igb_gstrings_test, sizeof(igb_gstrings_test));
                break;
        case ETH_SS_STATS:
                for (i = 0; i < IGB_GLOBAL_STATS_LEN; i++)