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Date:   Mon, 26 Sep 2022 20:01:25 +0200
Message-ID: <87leq6gglm.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     butt3rflyh4ck <butterflyhuangxx@gmail.com>
Cc:     perex@perex.cz, tiwai@suse.com,
        pierre-louis.bossart@linux.intel.com, broonie@kernel.org,
        alsa-devel@alsa-project.org, LKML <linux-kernel@vger.kernel.org>
Subject: Re: A divide error bug in snd_pcm_write
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On Mon, 26 Sep 2022 19:16:48 +0200,
butt3rflyh4ck wrote:
> 
> The latest kernel upstream.
> Yes, but using mmap, you can map the runtime->status page, and then
> copy the data through memcpy to overwrite the status->state data, or
> even more, which is incredible.

Ah, then that's exactly the case my latest patch set covers.
Either the first patch or the second patch alone should work.
  https://lore.kernel.org/r/20220926135558.26580-2-tiwai@suse.de
  https://lore.kernel.org/r/20220926135558.26580-3-tiwai@suse.de

Could you verify either of them fixes the problem?


thanks,

Takashi