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Date:   Sun, 27 Mar 2022 10:33:19 +0200
Message-ID: <s5hwngflrqo.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Xiaomeng Tong <xiam0nd.tong@gmail.com>
Cc:     perex@perex.cz, tiwai@suse.com, krzysztof.h1@wp.pl,
        alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org
Subject: Re: [PATCH] cs423x: cs4236: fix an incorrect NULL check on list iterator
In-Reply-To: <20220327060822.4735-1-xiam0nd.tong@gmail.com>
References: <20220327060822.4735-1-xiam0nd.tong@gmail.com>
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On Sun, 27 Mar 2022 08:08:22 +0200,
Xiaomeng Tong wrote:
> 
> The bug is here:
> 	err = snd_card_cs423x_pnp(dev, card->private_data, pdev, cdev);
> 
> The list iterator value 'cdev' will *always* be set and non-NULL
> by list_for_each_entry(), so it is incorrect to assume that the
> iterator value will be NULL if the list is empty or no element
> is found.
> 
> To fix the bug, use a new variable 'iter' as the list iterator,
> while use the original variable 'cdev' as a dedicated pointer
> to point to the found element. And snd_card_cs423x_pnp() itself
> has NULL check for cdev.
> 
> Cc: stable@vger.kernel.org
> Fixes: c2b73d1458014 ("ALSA: cs4236: cs4232 and cs4236 driver merge to solve PnP BIOS detection")
> Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>

Thanks, applied now.


Takashi