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Message-ID: <d044b556-d97f-218f-4282-5d87be6a8ef9@embeddedor.com>
Date:   Sun, 1 Oct 2023 08:53:30 +0200
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Subject: Re: [PATCH][next] ALSA: 6fire: Fix undefined behavior bug in struct
 midi_runtime
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To:     Kees Cook <keescook@chromium.org>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc:     Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.com>,
        Torsten Schenk <torsten.schenk@zoho.com>,
        alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org
References: <ZRb2CKHuaCu0u38i@work> <202309291026.06071AC@keescook>
From:   "Gustavo A. R. Silva" <gustavo@embeddedor.com>
In-Reply-To: <202309291026.06071AC@keescook>
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On 9/29/23 19:27, Kees Cook wrote:
> On Fri, Sep 29, 2023 at 06:06:32PM +0200, Gustavo A. R. Silva wrote:
>> `struct urb` is a flexible structure, which means that it contains a
>> flexible-array member at the bottom. This could potentially lead to an
>> overwrite of the objects following `out_urb` in `struct midi_runtime`,
>> among them a function pointer.
>>
>> Fix this by placing the declaration of object `out_urb` at the end of
>> `struct midi_runtime`.
>>
>> Fixes: c6d43ba816d1 ("ALSA: usb/6fire - Driver for TerraTec DMX 6Fire USB")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
> 
> Another good find. :)

There are more coming. :)

> 
> Reviewed-by: Kees Cook <keescook@chromium.org>
> 

Thanks!
--
Gustavo