Re: [syzbot] general protection fault in __device_attach

From: Dan Carpenter
Date: Mon Jun 06 2022 - 08:48:18 EST


On Sat, Jun 04, 2022 at 10:32:46AM +0200, 'Dmitry Vyukov' via syzkaller-bugs wrote:
> On Fri, 3 Jun 2022 at 18:12, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >
> > But again, is this a "real and able to be triggered from userspace"
> > problem, or just fault-injection-induced?
>
> Then this is something to fix in the fault injection subsystem.
> Testing systems shouldn't be reporting false positives.
> What allocations cannot fail in real life? Is it <=page_size?
>

Apparently in 2014, anything less than *EIGHT?!!* pages succeeded!

https://lwn.net/Articles/627419/

I have been on the look out since that article and never seen anyone
mention it changing. I think we should ignore that and say that
anything over PAGE_SIZE can fail. Possibly we could go smaller than
PAGE_SIZE...

regards,
dan carpenter