[lvc-project] [PATCH] ALSA: hda: cs35l41: Fix NULL pointer dereference in cs35l41_hda_read_acpi()

[Richard Fitzgerald]

On 02/12/2025 10:13 am, Denis Arefev wrote:
> The acpi_get_first_physical_node() function can return NULL, in which
> case the get_device() function also returns NULL, but this value is
> then dereferenced without checking,so add a check to prevent a crash.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Fixes: 7b2f3eb492da ("ALSA: hda: cs35l41: Add support for CS35L41 in HDA systems")
> Cc: stable at vger.kernel.org
> Signed-off-by: Denis Arefev <arefev at swemel.ru>
> ---
>   sound/hda/codecs/side-codecs/cs35l41_hda.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/sound/hda/codecs/side-codecs/cs35l41_hda.c b/sound/hda/codecs/side-codecs/cs35l41_hda.c
> index c0f2a3ff77a1..21e00055c0c4 100644
> --- a/sound/hda/codecs/side-codecs/cs35l41_hda.c
> +++ b/sound/hda/codecs/side-codecs/cs35l41_hda.c
> @@ -1901,6 +1901,8 @@ static int cs35l41_hda_read_acpi(struct cs35l41_hda *cs35l41, const char *hid, i
>   
>   	cs35l41->dacpi = adev;
>   	physdev = get_device(acpi_get_first_physical_node(adev));
> +	if (!physdev)
> +		return -ENODEV;
>   
>   	sub = acpi_get_subsystem_id(ACPI_HANDLE(physdev));
>   	if (IS_ERR(sub))
Reviewed-by: Richard Fitzgerald <rf at opensource.cirrus.com>