On Tue, 2017-05-09 at 16:23 -0700, Kees Cook wrote:
> Using memcpy() from a string that is shorter than the length copied means
> the destination buffer is being filled with arbitrary data from the kernel
> rodata segment. Instead, use strncpy() which will fill the trailing bytes
> with zeros. Additionally adjust indentation to keep checkpatch.pl happy.
> 
> This was found with the future CONFIG_FORTIFY_SOURCE feature.
[]
> diff --git a/drivers/net/wireless/marvell/libertas/mesh.c 
> b/drivers/net/wireless/marvell/libertas/mesh.c
[]
> @@ -1177,9 +1177,9 @@ void lbs_mesh_ethtool_get_strings(struct net_device 
> *dev,
>       switch (stringset) {
>       case ETH_SS_STATS:
>               for (i = 0; i < MESH_STATS_NUM; i++) {
> -                     memcpy(s + i * ETH_GSTRING_LEN,
> -                                     mesh_stat_strings[i],
> -                                     ETH_GSTRING_LEN);
> +                     strncpy(s + i * ETH_GSTRING_LEN,
> +                             mesh_stat_strings[i],
> +                             ETH_GSTRING_LEN);
>               }

The better solution is to declare
mesh_stat_strings in in the normal way

---
 drivers/net/wireless/marvell/libertas/mesh.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/marvell/libertas/mesh.c 
b/drivers/net/wireless/marvell/libertas/mesh.c
index d0c881dd5846..a535e7f48d2d 100644
--- a/drivers/net/wireless/marvell/libertas/mesh.c
+++ b/drivers/net/wireless/marvell/libertas/mesh.c
@@ -1108,15 +1108,15 @@ void lbs_mesh_set_txpd(struct lbs_private *priv,
  * Ethtool related
  */
 
-static const char * const mesh_stat_strings[] = {
-                       "drop_duplicate_bcast",
-                       "drop_ttl_zero",
-                       "drop_no_fwd_route",
-                       "drop_no_buffers",
-                       "fwded_unicast_cnt",
-                       "fwded_bcast_cnt",
-                       "drop_blind_table",
-                       "tx_failed_cnt"
+static const char mesh_stat_strings[][ETH_GSTRING_LEN] = {
+       "drop_duplicate_bcast",
+       "drop_ttl_zero",
+       "drop_no_fwd_route",
+       "drop_no_buffers",
+       "fwded_unicast_cnt",
+       "fwded_bcast_cnt",
+       "drop_blind_table",
+       "tx_failed_cnt",
 };
 
 void lbs_mesh_ethtool_get_stats(struct net_device *dev,

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