In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields. Use memset_startat() so memset() doesn't get confused about writing beyond the destination member that is intended to be the starting point of zeroing through the end of the struct. Cc: Jes Sorensen <jes@xxxxxxxxxxxxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: Jakub Kicinski <kuba@xxxxxxxxxx> Cc: linux-hippi@xxxxxxxxxx Cc: netdev@xxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- net/802/hippi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/802/hippi.c b/net/802/hippi.c index f80b33a8f7e0..6f71ffc8bdd1 100644 --- a/net/802/hippi.c +++ b/net/802/hippi.c @@ -65,7 +65,7 @@ static int hippi_header(struct sk_buff *skb, struct net_device *dev, hip->le.src_addr_type = 2; /* 12 bit SC address */ memcpy(hip->le.src_switch_addr, dev->dev_addr + 3, 3); - memset(&hip->le.reserved, 0, 16); + memset_startat(&hip->le, 0, reserved); hip->snap.dsap = HIPPI_EXTENDED_SAP; hip->snap.ssap = HIPPI_EXTENDED_SAP; -- 2.30.2