Re: [PATCH] kasan: Respect /proc/sys/kernel/traceoff_on_warning

From: Alexander Potapenko
Date: Wed Jan 25 2017 - 09:38:30 EST


On Wed, Jan 25, 2017 at 3:25 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> After much waiting I finally reproduced a KASAN issue, only to find my
> trace-buffer empty of useful information because it got spooled out :/
>
> Make kasan_report honour the /proc/sys/kernel/traceoff_on_warning
> interface.
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Alexander Potapenko <glider@xxxxxxxxxx>
> ---
> mm/kasan/report.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/mm/kasan/report.c b/mm/kasan/report.c
> index b82b3e2..6ff7efc 100644
> --- a/mm/kasan/report.c
> +++ b/mm/kasan/report.c
> @@ -300,6 +300,8 @@ void kasan_report(unsigned long addr, size_t size,
> if (likely(!kasan_report_enabled()))
> return;
>
> + disable_trace_on_warning();
> +
> info.access_addr = (void *)addr;
> info.access_size = size;
> info.is_write = is_write;



--
Alexander Potapenko
Software Engineer

Google Germany GmbH
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