Re: [PATCH] usb: typec: mux: initialize orientation switch array

Sebastian Reichel <[email protected]> Wed, 5 Aug 2026 02:28:13 +0200

Newsgroups	org.kernel.vger.linux-kernel,org.kernel.vger.linux-usb
Message-ID	<anKDIaz2GWjdm2U0@venus>

Hi,

On Tue, Aug 04, 2026 at 04:34:34PM +0800, Haobo Cheng wrote:
> Commit a53b4f9c51a9 ("usb: typec: mux: avoid duplicated orientation
> switches") started using the orientation switch result array as state for
> duplicate detection, but left the array uninitialized.
> 
> The first match therefore scans indeterminate stack contents before any
> result has been stored. A valid orientation switch may be incorrectly
> discarded as a duplicate, causing fwnode_typec_switch_get() to return no
> switch.
> 
> Zero-initialize the array before collecting matches.
> 
> Fixes: a53b4f9c51a9 ("usb: typec: mux: avoid duplicated orientation switches")
> Signed-off-by: Haobo Cheng <[email protected]>
> ---

oops.

Cc: [email protected]
Reviewed-by: Sebastian Reichel <[email protected]>

Greetings,

-- Sebastian

>  drivers/usb/typec/mux.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/mux.c b/drivers/usb/typec/mux.c
> index 9b908c46b..55dab1c76 100644
> --- a/drivers/usb/typec/mux.c
> +++ b/drivers/usb/typec/mux.c
> @@ -79,7 +79,7 @@ static void *typec_switch_match(const struct fwnode_handle *fwnode,
>   */
>  struct typec_switch *fwnode_typec_switch_get(struct fwnode_handle *fwnode)
>  {
> -	struct typec_switch_dev *sw_devs[TYPEC_MUX_MAX_DEVS];
> +	struct typec_switch_dev *sw_devs[TYPEC_MUX_MAX_DEVS] = { };
>  	struct typec_switch *sw;
>  	int count;
>  	int err;
> -- 
> 2.53.0
>

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