linux-kernel - Re: [PATCH 3/8] usb: typec: intel_pmc

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <xzk3yjkf4zew4p3f4jo6an3cnp4qe2vcvdbu6eq4ths5q4aqmp@4d2qfvrdwym5>
Date: Wed, 25 Sep 2024 19:54:07 +0300
From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To: Abhishek Pandit-Subedi <abhishekpandit@...omium.org>
Cc: heikki.krogerus@...ux.intel.com, tzungbi@...nel.org, jthies@...gle.com, 
	pmalani@...omium.org, akuchynski@...gle.com, 
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>, linux-kernel@...r.kernel.org, linux-usb@...r.kernel.org
Subject: Re: [PATCH 3/8] usb: typec: intel_pmc_mux: Null check before use

On Wed, Sep 25, 2024 at 09:25:04AM GMT, Abhishek Pandit-Subedi wrote:
> Make sure the data pointer in typec_mux_state is not null before
> accessing it.
> 
> Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@...omium.org>

Is the a fix for an actual issue or just good-to-have thing? In the
former case it lacks a description of how the issue can be triggered and
a Fixes tag.

> ---
> 
>  drivers/usb/typec/mux/intel_pmc_mux.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/typec/mux/intel_pmc_mux.c b/drivers/usb/typec/mux/intel_pmc_mux.c
> index 56989a0d0f43..4283fead9a69 100644
> --- a/drivers/usb/typec/mux/intel_pmc_mux.c
> +++ b/drivers/usb/typec/mux/intel_pmc_mux.c
> @@ -331,14 +331,19 @@ static int
>  pmc_usb_mux_tbt(struct pmc_usb_port *port, struct typec_mux_state *state)
>  {
>  	struct typec_thunderbolt_data *data = state->data;
> -	u8 cable_rounded = TBT_CABLE_ROUNDED_SUPPORT(data->cable_mode);
> -	u8 cable_speed = TBT_CABLE_SPEED(data->cable_mode);
> +	u8 cable_rounded, cable_speed;
>  	struct altmode_req req = { };
>  
> +	if (!data)
> +		return 0;
> +
>  	if (IOM_PORT_ACTIVITY_IS(port->iom_status, TBT) ||
>  	    IOM_PORT_ACTIVITY_IS(port->iom_status, ALT_MODE_TBT_USB))
>  		return 0;
>  
> +	cable_rounded = TBT_CABLE_ROUNDED_SUPPORT(data->cable_mode);
> +	cable_speed = TBT_CABLE_SPEED(data->cable_mode);
> +
>  	req.usage = PMC_USB_ALT_MODE;
>  	req.usage |= port->usb3_port << PMC_USB_MSG_USB3_PORT_SHIFT;
>  	req.mode_type = PMC_USB_MODE_TYPE_TBT << PMC_USB_MODE_TYPE_SHIFT;
> -- 
> 2.46.0.792.g87dc391469-goog
> 

-- 
With best wishes
Dmitry