On Tue, Dec 20, 2022 at 08:36:51AM -0800, matthew.gerlach@xxxxxxxxxxxxxxx wrote:
> From: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
>
> Version 1 of the Device Feature Header (DFH) definition adds
> functionality to the DFL bus.
>
> A DFHv1 header may have one or more parameter blocks that
> further describes the HW to SW. Add support to the DFL bus
> to parse the MSI-X parameter.
>
> The location of a feature's register set is explicitly
> described in DFHv1 and can be relative to the base of the DFHv1
> or an absolute address. Parse the location and pass the information
> to DFL driver.
...
> +/**
> + * dfh_find_param() - find data for the given parameter id
> + * @dfl_dev: dfl device
> + * @param: id of dfl parameter
> + *
> + * Return: pointer to parameter header on success, NULL otherwise.
header is a bit confusing here, does it mean we give and ID and we got
something more than just a data as summary above suggests?
In such case summary and this text should clarify what exactly we get
and layout of the data. Since this is a pointer, who is responsible of
checking out-of-boundary accesses? For instance, if the parameters are
variadic by length the length should be returned as well. Otherwise it
should be specified as a constant somewhere, right?
> + */
> +u64 *dfh_find_param(struct dfl_device *dfl_dev, int param_id)
> +{
> + return find_param(dfl_dev->params, dfl_dev->param_size, param_id);
> +}
> +EXPORT_SYMBOL_GPL(dfh_find_param);
...
> + finfo = kzalloc(sizeof(*finfo) + dfh_psize, GFP_KERNEL);
It sounds like a candidate for struct_size() from overflow.h.
I.o.w. check that header and come up with the best what can
suit your case.
> if (!finfo)
> return -ENOMEM;
--
With Best Regards,
Andy Shevchenko
