[PATCH 2.6.28] bluetooth: fix leak of uninitialized data to userspace

Vegard Nossum
2008-10-05T15:38:40Z

>From 45be27894a18f87b71b855fcc4afd50f860254b4 Mon Sep 17 00:00:00 2001
From: Vegard Nossum <vegard.nossum@gmail.com>
Date: Sun, 5 Oct 2008 17:25:45 +0200
Subject: [PATCH] bluetooth: fix leak of uninitialized data to userspace

struct hci_dev_list_req {
__u16 dev_num;
struct hci_dev_req dev_req[0]; /* hci_dev_req structures */
};

sizeof(struct hci_dev_list_req) == 4, so the two bytes immediately
following "dev_num" will never be initialized. When this structure
is copied to userspace, these uninitialized bytes are leaked.

Fix by using kzalloc() instead of kmalloc(). Found using kmemcheck.

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
---
net/bluetooth/hci_core.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 278a3ac..7bb0f1c 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -756,7 +756,7 @@ int hci_get_dev_list(void __user *arg)

size = sizeof(*dl) + dev_num * sizeof(*dr);

- if (!(dl = kmalloc(size, GFP_KERNEL)))
+ if (!(dl = kzalloc(size, GFP_KERNEL)))
return -ENOMEM;

dr = dl->dev_req;
--
1.5.5.1