Re: [PATCH v1 1/1] mac_pton: Don't access memory over expected length

From: Andy Shevchenko
Date: Tue Nov 08 2022 - 08:52:07 EST


On Mon, Oct 10, 2022 at 05:38:09PM -0700, Jakub Kicinski wrote:
> On Mon, 10 Oct 2022 22:19:49 +0200 Andrew Lunn wrote:
> > On Wed, Oct 05, 2022 at 07:43:01PM +0300, Andy Shevchenko wrote:
> > > The strlen() may go too far when estimating the length of
> > > the given string. In some cases it may go over the boundary
> > > and crash the system which is the case according to the commit
> > > 13a55372b64e ("ARM: orion5x: Revert commit 4904dbda41c8.").
> > >
> > > Rectify this by switching to strnlen() for the expected
> > > maximum length of the string.
> >
> > This seems like something which should have a fixes: tag, and be
> > against net, not net-next.
>
> Quoting DaveM's revert mentioned in the commit message:
>
> First of all, the orion5x buffer is not NULL terminated. mac_pton()
> has no business operating on non-NULL terminated buffers because
> only the caller can know that this is valid and in what manner it
> is ok to parse this NULL'less buffer.
>
> Second of all, orion5x operates on an __iomem pointer, which cannot
> be dereferenced using normal C pointer operations. Accesses to
> such areas much be performed with the proper iomem accessors.
>
> So AFAICT only null-terminated strings are expected here, this patch
> does not fix any known issue. No need to put it in net (if it's needed
> at all).

So, what is the decision with this patch? Should I resend that with net-next
in the subject?

--
With Best Regards,
Andy Shevchenko