All of lore.kernel.org
 help / color / mirror / Atom feed
From: Steffen Klassert <steffen.klassert@secunet.com>
To: David Miller <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>,
	Steffen Klassert <steffen.klassert@secunet.com>,
	<netdev@vger.kernel.org>
Subject: [PATCH 6/7] xfrm_user: fix info leak in build_expire()
Date: Tue, 29 Aug 2017 12:31:33 +0200	[thread overview]
Message-ID: <1504002694-1931-7-git-send-email-steffen.klassert@secunet.com> (raw)
In-Reply-To: <1504002694-1931-1-git-send-email-steffen.klassert@secunet.com>

From: Mathias Krause <minipli@googlemail.com>

The memory reserved to dump the expired xfrm state includes padding
bytes in struct xfrm_user_expire added by the compiler for alignment. To
prevent the heap info leak, memset(0) the remainder of the struct.
Initializing the whole structure isn't needed as copy_to_user_state()
already takes care of clearing the padding bytes within the 'state'
member.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_user.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index c33516e..2cbdc81 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2578,6 +2578,8 @@ static int build_expire(struct sk_buff *skb, struct xfrm_state *x, const struct
 	ue = nlmsg_data(nlh);
 	copy_to_user_state(x, &ue->state);
 	ue->hard = (c->data.hard != 0) ? 1 : 0;
+	/* clear the padding bytes */
+	memset(&ue->hard + 1, 0, sizeof(*ue) - offsetofend(typeof(*ue), hard));
 
 	err = xfrm_mark_put(skb, &x->mark);
 	if (err)
-- 
2.7.4

  parent reply	other threads:[~2017-08-29 10:31 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-29 10:31 pull request (net): ipsec 2017-08-29 Steffen Klassert
2017-08-29 10:31 ` [PATCH 1/7] net: xfrm: don't double-hold dst when sk_policy in use Steffen Klassert
2017-08-29 10:31 ` [PATCH 2/7] esp: Fix locking on page fragment allocation Steffen Klassert
2017-08-29 10:31 ` [PATCH 3/7] esp: Fix skb tailroom calculation Steffen Klassert
2017-08-29 10:31 ` [PATCH 4/7] xfrm_user: fix info leak in copy_user_offload() Steffen Klassert
2017-08-29 10:31 ` [PATCH 5/7] xfrm_user: fix info leak in xfrm_notify_sa() Steffen Klassert
2017-08-29 10:31 ` Steffen Klassert [this message]
2017-08-29 10:31 ` [PATCH 7/7] xfrm_user: fix info leak in build_aevent() Steffen Klassert
2017-08-29 16:37 ` pull request (net): ipsec 2017-08-29 David Miller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1504002694-1931-7-git-send-email-steffen.klassert@secunet.com \
    --to=steffen.klassert@secunet.com \
    --cc=davem@davemloft.net \
    --cc=herbert@gondor.apana.org.au \
    --cc=netdev@vger.kernel.org \
    --subject='Re: [PATCH 6/7] xfrm_user: fix info leak in build_expire()' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.