xfrm_user: fix info leak in copy_to_user_tmpl()

[ Upstream commit 1f86840f89 ]

The memory used for the template copy is a local stack variable. As
struct xfrm_user_tmpl contains multiple holes added by the compiler for
alignment, not initializing the memory will lead to leaking stack bytes
to userland. Add an explicit memset(0) to avoid the info leak.

Initial version of the patch by Brad Spengler.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Brad Spengler <spender@grsecurity.net>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mathias Krause
2012-09-19 11:33:41 +00:00
committed by Greg Kroah-Hartman
parent a601da719c
commit c33fcb85ee

View File

@@ -1405,6 +1405,7 @@ static int copy_to_user_tmpl(struct xfrm_policy *xp, struct sk_buff *skb)
struct xfrm_user_tmpl *up = &vec[i];
struct xfrm_tmpl *kp = &xp->xfrm_vec[i];
memset(up, 0, sizeof(*up));
memcpy(&up->id, &kp->id, sizeof(up->id));
up->family = kp->encap_family;
memcpy(&up->saddr, &kp->saddr, sizeof(up->saddr));