linux-kernel - [PATCH 22/50] l2tp: Fix PPP header erasure and memory leak

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1372763258-20664-23-git-send-email-luis.henriques@canonical.com>
Date:	Tue,  2 Jul 2013 12:07:10 +0100
From:	Luis Henriques <luis.henriques@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	Guillaume Nault <g.nault@...halink.fr>,
	"David S. Miller" <davem@...emloft.net>,
	Luis Henriques <luis.henriques@...onical.com>
Subject: [PATCH 22/50] l2tp: Fix PPP header erasure and memory leak

3.5.7.16 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Guillaume Nault <g.nault@...halink.fr>

commit 55b92b7a11690bc377b5d373872a6b650ae88e64 upstream.

Copy user data after PPP framing header. This prevents erasure of the
added PPP header and avoids leaking two bytes of uninitialised memory
at the end of skb's data buffer.

Signed-off-by: Guillaume Nault <g.nault@...halink.fr>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Luis Henriques <luis.henriques@...onical.com>
---
 net/l2tp/l2tp_ppp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index 46c7cc7..42dfd0e 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -345,12 +345,12 @@ static int pppol2tp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msgh
 	skb_put(skb, 2);
 
 	/* Copy user data into skb */
-	error = memcpy_fromiovec(skb->data, m->msg_iov, total_len);
+	error = memcpy_fromiovec(skb_put(skb, total_len), m->msg_iov,
+				 total_len);
 	if (error < 0) {
 		kfree_skb(skb);
 		goto error_put_sess_tun;
 	}
-	skb_put(skb, total_len);
 
 	l2tp_xmit_skb(session, skb, session->hdr_len);
 
-- 
1.8.1.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/