From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755027Ab2IQBDs (ORCPT ); Sun, 16 Sep 2012 21:03:48 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33793 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753149Ab2IQAvG (ORCPT ); Sun, 16 Sep 2012 20:51:06 -0400 Message-Id: <20120917003634.675829665@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 17 Sep 2012 01:37:26 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Mathias Krause , Marcel Holtmann , Gustavo Padovan , Johan Hedberg , "David S. Miller" Subject: [ 061/135] Bluetooth: RFCOMM - Fix info leak in getsockopt(BT_SECURITY) In-Reply-To: <20120917003625.784119135@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Krause [ Upstream commit 9ad2de43f1aee7e7274a4e0d41465489299e344b ] The RFCOMM code fails to initialize the key_size member of struct bt_security before copying it to userland -- that for leaking one byte kernel stack. Initialize key_size with 0 to avoid the info leak. Signed-off-by: Mathias Krause Cc: Marcel Holtmann Cc: Gustavo Padovan Cc: Johan Hedberg Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/bluetooth/rfcomm/sock.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c index 5417f61..03584bc 100644 --- a/net/bluetooth/rfcomm/sock.c +++ b/net/bluetooth/rfcomm/sock.c @@ -835,6 +835,7 @@ static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, c } sec.level = rfcomm_pi(sk)->sec_level; + sec.key_size = 0; len = min_t(unsigned int, len, sizeof(sec)); if (copy_to_user(optval, (char *) &sec, len))