Re: [PATCH] platform/x86: ideapad-laptop: fix a NULL pointer dereference

From: Ike Panhc
Date: Fri Apr 30 2021 - 04:45:23 EST


On 4/28/21 1:06 PM, Qiu Wenbo wrote:
> The third parameter of dytc_cql_command should not be NULL since it will
> be dereferenced immediately.
>
> Signed-off-by: Qiu Wenbo <qiuwenbo@xxxxxxxxxxxxxx>

Fixes: ff36b0d953dc4 ("platform/x86: ideapad-laptop: rework and create new ACPI helpers")
Acked-by: Ike Panhc <ike.pan@xxxxxxxxxxxxx>

> ---
> drivers/platform/x86/ideapad-laptop.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/platform/x86/ideapad-laptop.c b/drivers/platform/x86/ideapad-laptop.c
> index 6cb5ad4be231..8f871151f0cc 100644
> --- a/drivers/platform/x86/ideapad-laptop.c
> +++ b/drivers/platform/x86/ideapad-laptop.c
> @@ -809,6 +809,7 @@ static int dytc_profile_set(struct platform_profile_handler *pprof,
> {
> struct ideapad_dytc_priv *dytc = container_of(pprof, struct ideapad_dytc_priv, pprof);
> struct ideapad_private *priv = dytc->priv;
> + unsigned long output;
> int err;
>
> err = mutex_lock_interruptible(&dytc->mutex);
> @@ -829,7 +830,7 @@ static int dytc_profile_set(struct platform_profile_handler *pprof,
>
> /* Determine if we are in CQL mode. This alters the commands we do */
> err = dytc_cql_command(priv, DYTC_SET_COMMAND(DYTC_FUNCTION_MMC, perfmode, 1),
> - NULL);
> + &output);
> if (err)
> goto unlock;
> }
>