Re: [PATCH] kasan: report only the first error

[Andrey Ryabinin]

On 03/22/2017 07:34 PM, Andrey Konovalov wrote:
> On Wed, Mar 22, 2017 at 5:06 PM, Andrey Ryabinin
> <aryabinin@xxxxxxxxxxxxx> wrote:
>> Disable kasan after the first report. There are several reasons for this:
>>  * Single bug quite often has multiple invalid memory accesses causing
>>     storm in the dmesg.
>>  * Write OOB access might corrupt metadata so the next report will print
>>     bogus alloc/free stacktraces.
>>  * Reports after the first easily could be not bugs by itself but just side
>>     effects of the first one.
>>
>> Given that multiple reports only do harm, it makes sense to disable
>> kasan after the first one. Except for the tests in lib/test_kasan.c
>> as we obviously want to see all reports from test.
> 
> Hi Andrey,
> 
> Could you make it configurable via CONFIG_KASAN_SOMETHING (which can
> default to showing only the first report)?

I'd rather make this boot time configurable, but wouldn't want to without
a good reason.


> I sometimes use KASAN to see what bad accesses a particular bug
> causes, and seeing all of them (even knowing that they may be
> corrupt/induced) helps a lot.

I'm wondering why you need to see all reports?

> 
> Thanks!
>