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From:   Tzung-Bi Shih <tzungbi@google.com>
Date:   Fri, 4 Dec 2020 17:05:37 +0800
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Subject: Re: [PATCH] ASoC: cros_ec_codec: fix uninitialized memory read
To:     Arnd Bergmann <arnd@kernel.org>
Cc:     Cheng-Yi Chiang <cychiang@chromium.org>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>,
        Benson Leung <bleung@chromium.org>,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Guenter Roeck <groeck@chromium.org>,
        ALSA development <alsa-devel@alsa-project.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Fri, Dec 4, 2020 at 4:28 PM Arnd Bergmann <arnd@kernel.org> wrote:
>
> On Fri, Dec 4, 2020 at 3:56 AM Tzung-Bi Shih <tzungbi@google.com> wrote:
> >
> > On Fri, Dec 4, 2020 at 6:55 AM Arnd Bergmann <arnd@kernel.org> wrote:
> >
> > In the case in i2s_rx_event(), only the "cmd" member is used.  But it
> > is fine to please the compiler.
>
> I wouldn't do it just to please the compiler. I sent this patch since
> the code clearly copies the uninitialized data here. If only
> one byte is meant to be copied, then we should change the
> function call to not pass the entire structure. I'll send a new
> patch for that.

My sentence may confuse you.  But I mean: the uninitialized data
doesn't introduce any bugs because it only uses the first byte in the
case.

Instead of your v2
(https://patchwork.kernel.org/project/alsa-devel/patch/20201204083624.2711356-1-arnd@kernel.org/),
I prefer this version v1.