Re: [PATCH v3 2/2] hwmon: (pmbus/vt7505) Add driver for Analog Devices MAX16545/MAX16550 and Volterra VT7505

[Guenter Roeck <linux@roeck-us.net>]

On Fri, Jul 24, 2026 at 04:50:00PM +0000, Pradhan, Sanman wrote:
> From: Georgi Vlaev <gvlaev@juniper.net>
> 
> Add a PMBus driver for the Analog Devices MAX16545 and MAX16550, and the
> Volterra VT7505 controllers. The driver reports input/output voltage,
> input/output current, input power and temperature over PMBus. All values
> use the direct data format. Peak input voltage, output voltage, output
> current, input power and temperature readings are exposed and can be
> reset.
> 
> The reported current and power depend on the external current-report
> resistor connected to the ILOAD pin, which can be provided through the
> "adi,rload-ohms" device tree property.
> 
> On the MAX16550 and VT7505, the severe-OCP deglitch time can optionally
> be configured with the "adi,ocp-severe-filter-us" device tree property.
> When omitted, the existing hardware setting is left unchanged.
> 
...
> +static void vt7505_set_m(int *m, u32 rload)
> +{
> +	u64 val = (u64)*m * rload;
> +
> +	/* Make sure m fits the s32 type */
> +	*m = DIV_ROUND_CLOSEST_ULL(val, 1000);

The largest possible value of m is 7578. That means that this _will_
overflow if rload >= 283383960 because 283383960 * 7578 / 1000 =
2147483648.88, rounded up to to 2147483649 == 0x80000001.

Please add a range check in the probe function.

Thanks,
Guenter