From caf283d040f53bc4fd81ce3d2a1a364b069cfd7d Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 17 Jun 2021 08:34:19 -0700 Subject: xfrm: Use memset_after() to clear padding In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields. Clear trailing padding bytes using the new helper so that memset() doesn't get confused about writing "past the end" of the last struct member. There is no change to the resulting machine code. Cc: Steffen Klassert Cc: Herbert Xu Cc: "David S. Miller" Cc: Jakub Kicinski Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook --- net/xfrm/xfrm_policy.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'net/xfrm/xfrm_policy.c') diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 37d17a79617c..1a06585022ab 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -2486,9 +2486,7 @@ static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family) xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0); if (likely(xdst)) { - struct dst_entry *dst = &xdst->u.dst; - - memset(dst + 1, 0, sizeof(*xdst) - sizeof(*dst)); + memset_after(xdst, 0, u.dst); } else xdst = ERR_PTR(-ENOBUFS); -- cgit v1.2.3