From 352e3a79d7885339ea18c4bad77d4508616fa61c Mon Sep 17 00:00:00 2001
From: Mathias Krause <minipli@googlemail.com>
Date: Wed, 15 Aug 2012 11:31:48 +0000
Subject: [PATCH] Bluetooth: RFCOMM - Fix info leak in getsockopt(BT_SECURITY)

[ 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 <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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 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 e8707debb864..b7afb480f228 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -841,6 +841,7 @@ 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))
-- 
2.39.5