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From:   Andrey Konovalov <andreyknvl@gmail.com>
Date:   Fri, 15 Sep 2023 18:50:48 +0200
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Subject: Re: [PATCH] kasan:fix access invalid shadow address when input is illegal
To:     Haibo Li <haibo.li@mediatek.com>, jannh@google.com
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        dvyukov@google.com, glider@google.com, kasan-dev@googlegroups.com,
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        xiaoming.yu@mediatek.com
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On Fri, Sep 15, 2023 at 4:46=E2=80=AFAM 'Haibo Li' via kasan-dev
<kasan-dev@googlegroups.com> wrote:
>
> The patch checks each shadow address,so it introduces extra overhead.

Ack. Could still be fine, depends on the overhead.

But if the message printed by kasan_non_canonical_hook is good enough
for your use case, I would rather stick to that.

> Now kasan_non_canonical_hook only works for CONFIG_KASAN_INLINE.
>
> And CONFIG_KASAN_OUTLINE is set in my case.
>
> Is it possible to make kasan_non_canonical_hook works for both
> INLINE and OUTLINE by simply remove the "#ifdef CONFIG_KASAN_INLINE"?

Yes, it should just work if you remove the ifdefs in mm/kasan/report.c
and in include/linux/kasan.h.

Jann, do you have any objections to enabling kasan_non_canonical_hook
for the outline mode too?

> Since kasan_non_canonical_hook is only used after kernel fault,it
> is better if there is no limit.