Re: [PATCH v3] kunit: kasan_test: disable fortify string checker on kasan_strings() test

[Yeoreum Yun <yeoreum.yun@arm.com>]

Hi Andrew,

> > Similar to commit 09c6304e38e4 ("kasan: test: fix compatibility with
> > FORTIFY_SOURCE") the kernel is panicing in kasan_string().
> >
> > This is due to the `src` and `ptr` not being hidden from the optimizer
> > which would disable the runtime fortify string checker.
> >
> > Call trace:
> >   __fortify_panic+0x10/0x20 (P)
> >   kasan_strings+0x980/0x9b0
> >   kunit_try_run_case+0x68/0x190
> >   kunit_generic_run_threadfn_adapter+0x34/0x68
> >   kthread+0x1c4/0x228
> >   ret_from_fork+0x10/0x20
> >  Code: d503233f a9bf7bfd 910003fd 9424b243 (d4210000)
> >  ---[ end trace 0000000000000000 ]---
> >  note: kunit_try_catch[128] exited with irqs disabled
> >  note: kunit_try_catch[128] exited with preempt_count 1
> >      # kasan_strings: try faulted: last
> > ** replaying previous printk message **
> >      # kasan_strings: try faulted: last line seen mm/kasan/kasan_test_c.c:1600
> >      # kasan_strings: internal error occurred preventing test case from running: -4
> >
>
> We don't want -stable kernels to panic either.  I'm thinking
>
> Fixes: 73228c7ecc5e ("KASAN: port KASAN Tests to KUnit")
> Cc: <stable@vger.kernel.org>
>
> What do you think?
>
> We could perhaps go back earlier in time, but 73228c7ecc5e is 5 years
> old.

Unless others feel differently, your suggestion works for me.
I had considered including it earlier, but wasn’t entirely sure.

Thanks

--
Sincerely,
Yeoreum Yun