In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memset(), avoid intentionally writing across
neighboring fields.
Use memset_after() to clear everything after the dst_entry member of
struct rt6_info.
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Hideaki YOSHIFUJI <yoshfuji@xxxxxxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxxx>
Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
net/ipv6/route.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 6cf4bb89ca69..bd0ab3e436e7 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -327,9 +327,7 @@ static const struct rt6_info ip6_blk_hole_entry_template = {
static void rt6_info_init(struct rt6_info *rt)
{
- struct dst_entry *dst = &rt->dst;
-
- memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
+ memset_after(rt, 0, dst);
INIT_LIST_HEAD(&rt->rt6i_uncached);
}
--
2.30.2
