From: Mathias Krause <minipli@googlemail.com>
Date: Wed, 19 Sep 2012 11:33:40 +0000 (+0000)
Subject: xfrm_user: fix info leak in copy_to_user_policy()
X-Git-Tag: v3.2.31~29
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=bc39fa8d3deb34d5d0cfd86aafb8033ac4a4ed90;p=karo-tx-linux.git

xfrm_user: fix info leak in copy_to_user_policy()

[ Upstream commit 7b789836f434c87168eab067cfbed1ec4783dffd ]

The memory reserved to dump the xfrm policy includes multiple padding
bytes added by the compiler for alignment (padding bytes in struct
xfrm_selector and struct xfrm_userpolicy_info). Add an explicit
memset(0) before filling the buffer to avoid the heap info leak.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index f252cae35fa6..1d222e9b9be0 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1300,6 +1300,7 @@ static void copy_from_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy
 
 static void copy_to_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_info *p, int dir)
 {
+	memset(p, 0, sizeof(*p));
 	memcpy(&p->sel, &xp->selector, sizeof(p->sel));
 	memcpy(&p->lft, &xp->lft, sizeof(p->lft));
 	memcpy(&p->curlft, &xp->curlft, sizeof(p->curlft));