Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1392145

Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled()

From Alexander Potapenko <glider@google.com>
Newsgroups linux.kernel
Subject Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled()
Date 2016-05-02 13:40 +0200
Message-ID <rukmK-2pV-15@gated-at.bofh.it> (permalink)
References <ruf3I-6ho-7@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Mon, May 2, 2016 at 7:36 AM,  <chengang@emindsoft.com.cn> wrote:
> From: Chen Gang <chengang@emindsoft.com.cn>
>
> According to kasan_[dis|en]able_current() comments and the kasan_depth'
> s initialization, if kasan_depth is zero, it means disable.
The comments for those functions are really poor, but there's nothing
there that says kasan_depth==0 disables KASAN.
Actually, kasan_report_enabled() is currently the only place that
denotes the semantics of kasan_depth, so it couldn't be wrong.

init_task.kasan_depth is 1 during bootstrap and is then set to zero by
kasan_init()
For every other thread, current->kasan_depth is zero-initialized.

> So need use "!!kasan_depth" instead of "!kasan_depth" for checking
> enable.
>
> Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
> ---
>  mm/kasan/kasan.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
> index 7da78a6..6464b8f 100644
> --- a/mm/kasan/kasan.h
> +++ b/mm/kasan/kasan.h
> @@ -102,7 +102,7 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
>
>  static inline bool kasan_report_enabled(void)
>  {
> -       return !current->kasan_depth;
> +       return !!current->kasan_depth;
>  }
>
>  void kasan_report(unsigned long addr, size_t size,
> --
> 1.9.3
>



-- 
Alexander Potapenko
Software Engineer

Google Germany GmbH
Erika-Mann-Straße, 33
80636 München

Geschäftsführer: Matthew Scott Sucherman, Paul Terence Manicle
Registergericht und -nummer: Hamburg, HRB 86891
Sitz der Gesellschaft: Hamburg

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() chengang@emindsoft.com.cn - 2016-05-02 08:00 +0200
  Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Dmitry Vyukov <dvyukov@google.com> - 2016-05-02 10:30 +0200
    Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Chen Gang <chengang@emindsoft.com.cn> - 2016-05-02 13:20 +0200
      Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Dmitry Vyukov <dvyukov@google.com> - 2016-05-02 13:30 +0200
        Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Chen Gang <chengang@emindsoft.com.cn> - 2016-05-02 14:30 +0200
          Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Alexander Potapenko <glider@google.com> - 2016-05-02 14:50 +0200
            Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Chen Gang <chengang@emindsoft.com.cn> - 2016-05-02 15:50 +0200
              Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Alexander Potapenko <glider@google.com> - 2016-05-02 16:30 +0200
                Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Chen Gang <chengang@emindsoft.com.cn> - 2016-05-02 17:10 +0200
                Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Alexander Potapenko <glider@google.com> - 2016-05-02 17:40 +0200
                Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Chen Gang <chengang@emindsoft.com.cn> - 2016-05-02 18:20 +0200
                Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Chen Gang <chengang@emindsoft.com.cn> - 2016-05-02 18:40 +0200
  Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Alexander Potapenko <glider@google.com> - 2016-05-02 13:40 +0200
    Re: [PATCH] mm/kasan/kasan.h: Fix boolean checking issue for kasan_report_enabled() Chen Gang <chengang@emindsoft.com.cn> - 2016-05-02 14:10 +0200

csiph-web