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Date:   Fri, 29 Sep 2023 10:27:02 -0700
From:   Kees Cook <keescook@chromium.org>
To:     "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
Subject: Re: [PATCH][next] ALSA: 6fire: Fix undefined behavior bug in struct
 midi_runtime
Message-ID: <202309291026.06071AC@keescook>
References: <ZRb2CKHuaCu0u38i@work>
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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. :)

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

-- 
Kees Cook