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: firefly_0821_release~7541^2~553
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a601da719c73cedba80c788719594990e30a972f;p=firefly-linux-kernel-4.4.55.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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 8e878ebf49a5..b5215b40c815 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));