From: Mathias Krause Date: Wed, 19 Sep 2012 11:33:41 +0000 (+0000) Subject: xfrm_user: fix info leak in copy_to_user_tmpl() X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1f86840f897717f86d523a13e99a447e6a5d2fa5;p=linux-beck.git xfrm_user: fix info leak in copy_to_user_tmpl() 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. Cc: Brad Spengler Signed-off-by: Mathias Krause Acked-by: Steffen Klassert Signed-off-by: David S. Miller --- diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 84dd85ceeeea..8024b3dea8c2 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -1425,6 +1425,7 @@ 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));