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Date:   Wed, 07 Sep 2022 09:35:08 +0200
Message-ID: <87illzeixf.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Jianglei Nie <niejianglei2021@163.com>
Cc:     perex@perex.cz, tiwai@suse.com, alsa-devel@alsa-project.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ALSA: hda/ca0132: fix potential memory leak in dspxfr_image()
In-Reply-To: <20220907065917.55810-1-niejianglei2021@163.com>
References: <20220907065917.55810-1-niejianglei2021@163.com>
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On Wed, 07 Sep 2022 08:59:17 +0200,
Jianglei Nie wrote:
> 
> dspxfr_image() allocates DSP ports for the download stream with
> dsp_allocate_ports_format(). When gets some error, the allocated
> DSP ports are not released, which will lead to a memory leak.

Hmm, those allocate_* functions don't really allocate memories but
rather allocate virtual ports on the hardware; i.e. it just flips some
DSP registers.  There should be no "memory leaks".

> We can fix it by releasing DSP ports with dsp_free_ports() when
> getting some error.
> 
> Signed-off-by: Jianglei Nie <niejianglei2021@163.com>
> ---
>  sound/pci/hda/patch_ca0132.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c
> index 208933792787..6b8f45e14075 100644
> --- a/sound/pci/hda/patch_ca0132.c
> +++ b/sound/pci/hda/patch_ca0132.c
> @@ -3455,6 +3455,7 @@ static int dspxfr_image(struct hda_codec *codec,
>  					&port_map_mask);
>  	if (status < 0) {
>  		codec_dbg(codec, "alloc ports fail\n");
> +		dsp_free_ports(codec);

This is likely superfluous.  When an allocation fails, you don't free,
in general.


thanks,

Takashi