Re: [PATCH v6 RESEND] misc: sgi-gru: fix use-after-free error in gru_set_context_option, gru_fault and gru_handle_user_call_os

[Zheng Hacker]

Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> 于2022年11月9日周三 16:46写道：
>
> On Wed, Nov 09, 2022 at 04:41:42PM +0800, Zheng Wang wrote:
> > Gts may be freed in gru_check_chiplet_assignment.
> > The caller still use it after that, UAF happens.
> >
> > Fix it by introducing a return value to see if it's in error path or not.
> > Free the gts in caller if gru_check_chiplet_assignment check failed.
> >
> > Fixes: 55484c45dbec ("gru: allow users to specify gru chiplet 2")
> > Reported-by: Zheng Wang <hackerzheng666@xxxxxxxxx>
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> >
>
> Why the blank line?

> Sorry for the spelling problem, fixed it next version

> And the kernel test robot didn't find this issue, right?
>

Yes, it helped with the test and found an unused variable. I added
this line as the mail suggested
("If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@xxxxxxxxx>").

Should I remove it?

> > Signed-off-by: Zheng Wang <zyytlz.wz@xxxxxxx>
> > Acked-by: Dimitri Sivanich <sivanich@xxxxxxx>
>
> You can not have a reported-by and a signed-off-by for the same person
> with different email addresses.  You do not need both if it is you, just
> use the signed-off-by line.
>

Thanks very much for your explaination. I'll send another patch as
soon as possible.

Best Regards,
Zheng Wang