Re: [PATCH v6 8/9] vsprintf: Prevent crash when dereferencing invalid pointers

From: Andy Shevchenko
Date: Tue Feb 19 2019 - 08:50:06 EST


On Tue, Feb 19, 2019 at 09:51:15PM +0900, Sergey Senozhatsky wrote:
> On (02/19/19 13:02), Andy Shevchenko wrote:
> [..]
> > And if it's not? You will get in either case incomplete information,
> > but at least with "(e" (or even "(") you might get a clue that it
> > errornous conditions.
>
> The thing I'm signaling here is that in some cases we still can
> crash the kernel; with the difference that invalid dereference
> can now be a memory corruption. Just saying.

Wouldn't that mean that the culprit in the caller, not in the callee?

(As far as I got your another example with badly called sprintf() which may
overwrite stack, etc).

--
With Best Regards,
Andy Shevchenko