Re: [PATCH] media: atomisp: avoid ACPI package count underflow in gmin_cfg_get_dsm

From: Hans de Goede

Date: Fri Apr 10 2026 - 14:29:11 EST


Hi,

On 9-Apr-26 11:41 PM, Mohamed El Harake wrote:
> From: Mohamad El Harake <mohamedharake2006@xxxxxxxxx>
>
> gmin_cfg_get_dsm() iterates over ACPI _DSM package elements as
> key/value pairs using obj->package.count - 1 as the loop bound.
>
> If package.count is 0, the subtraction underflows and may lead
> to out-of-bounds access.
>
> Use i + 1 < obj->package.count instead.
>
> Signed-off-by: Mohamad El Harake <mohamedharake2006@xxxxxxxxx>

Thanks, patch looks good to me:

Reviewed-by: Hans de Goede <johannes.goede@xxxxxxxxxxxxxxxx>

Regards,

Hans



> ---
> drivers/staging/media/atomisp/pci/atomisp_csi2_bridge.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/staging/media/atomisp/pci/atomisp_csi2_bridge.c b/drivers/staging/media/atomisp/pci/atomisp_csi2_bridge.c
> index ba61cc28fac1..cca91c6d71a5 100644
> --- a/drivers/staging/media/atomisp/pci/atomisp_csi2_bridge.c
> +++ b/drivers/staging/media/atomisp/pci/atomisp_csi2_bridge.c
> @@ -113,7 +113,7 @@ static char *gmin_cfg_get_dsm(struct acpi_device *adev, const char *key)
> if (!obj)
> return NULL;
>
> - for (i = 0; i < obj->package.count - 1; i += 2) {
> + for (i = 0; i + 1 < obj->package.count; i += 2) {
> key_el = &obj->package.elements[i + 0];
> val_el = &obj->package.elements[i + 1];
>