From: Mathias Krause <minipli@googlemail.com>
Date: Wed, 15 Aug 2012 11:31:50 +0000 (+0000)
Subject: Bluetooth: RFCOMM - Fix info leak via getsockname()
X-Git-Tag: v2.6.34.15~84
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8ad4a5c58c7192de527ff2fd818fc362eb270013;p=thirdparty%2Fkernel%2Fstable.git

Bluetooth: RFCOMM - Fix info leak via getsockname()

commit 9344a972961d1a6d2c04d9008b13617bcb6ec2ef upstream.

The RFCOMM code fails to initialize the trailing padding byte of struct
sockaddr_rc added for alignment. It that for leaks one byte kernel stack
via the getsockname() syscall. Add an explicit memset(0) before filling
the structure to avoid the info leak.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---

diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index b045bbbc23533..92aa7a012110f 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -547,6 +547,7 @@ static int rfcomm_sock_getname(struct socket *sock, struct sockaddr *addr, int *
 
 	BT_DBG("sock %p, sk %p", sock, sk);
 
+	memset(sa, 0, sizeof(*sa));
 	sa->rc_family  = AF_BLUETOOTH;
 	sa->rc_channel = rfcomm_pi(sk)->channel;
 	if (peer)