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Subject: Re: [PATCH 2.6.28] bluetooth: fix leak of uninitialized data to
	userspace
From: Marcel Holtmann <marcel@holtmann.org>
To: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>, Pekka Enberg <penberg@cs.helsinki.fi>,
       linux-kernel@vger.kernel.org
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Date: Sun, 05 Oct 2008 18:24:15 +0200
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Hi Vegard,

> 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.

good catch. I thought we moved everything over to kzalloc, but as it
seems we forgot at least one. Applied your patch to me tree. Thanks.

Regards

Marcel