Re: [PATCH 1/3] driver core: add a faux bus for use when a simple device/bus is needed

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Mon, Feb 03, 2025 at 05:13:28PM +0100, Greg Kroah-Hartman wrote:
> On Mon, Feb 03, 2025 at 06:05:19PM +0200, Andy Shevchenko wrote:

...

> > > > > +	faux_obj = kzalloc(sizeof(*faux_obj) + strlen(name) + 1, GFP_KERNEL);
> > > > 
> > > > Potential overflow. To avoid one may use struct_size() from overflow.h.
> > > 
> > > Users should not be providing the string here.  Again, this comes from
> > > platform.c.
> > 
> > I'm not sure I follow. The name parameter is not limited anyhow, so one may
> > provide non-terminated string and strlen() will return an arbitrary number.
> > Potentially this can lead to big numbers and become an overflow when gets
> > to a parameter for kmalloc(). This most likely never happen in real life,
> > but still the overflow is possible.
> 
> I've now bounded at 256, because really, who needs a bigger name for a
> device than that :)

Works for me! With printable ASCII characters it can be estimated as up to
64^256 combinations, which "ought to be enough for everybody" (of course
it will be much less if we count only human-readable strings). :-)

-- 
With Best Regards,
Andy Shevchenko