Re: [PATCH] misc: uacce - add the null check for the input pointer and its pointer members

[huangchenghai]

在 2024/3/30 15:01, Greg KH 写道:
> On Sat, Mar 30, 2024 at 11:34:24AM +0800, huangchenghai wrote:
> > On Fri, Mar 29, 2024 at2:34PM, Greg KH wrote:
> >
> > > On Fri, Mar 29, 2024 at 02:26:55PM +0800, Chenghai Huang wrote:
> > > > The uacce_alloc() is the member of the EXPORT_SYMBOL_GPL. Therefore, null
> > > > pointer verification is added on the pointer type input parameter and its
> > > > pointer members.
> > > I do not understand, why does the export type matter?  Just fix any
> > > callers to use this properly and send proper parameters.  What in-tree
> > > caller needs this?
> > >
> > > thanks,
> > >
> > > greg k-h
> > The interface defined by the export type seems important and the input
> > parameters need to be verified.
> The export type does not matter at all.
>
> > But I understand from your mail that this is the job of the caller.
> Exactly.
>
> > By the way, I still have a confusion. Interfaces like ioctrl, debugfs, read,
> > or write require parameter validation. so what kind of kernel interfaces require
> > parameter validation? Is there a definition?
> Some do, some do not, it depends on the situation.  If data comes from
> an untrusted source (i.e. outside the kernel), then it MUST be validated
> (remember "all input is evil"), but if it's from within the kernel,
> usually it does not.
>
> thanks,
>
> greg k-h

I get it, thank you very much.

thanks,

Chenghai