Re: [PATCH v5 3/6] kasan: Add report for async mode

From: Vincenzo Frascino
Date: Fri Jan 22 2021 - 08:25:24 EST




On 1/22/21 1:19 PM, Catalin Marinas wrote:
> On Thu, Jan 21, 2021 at 04:39:40PM +0000, Vincenzo Frascino wrote:
>> diff --git a/include/linux/kasan.h b/include/linux/kasan.h
>> index bb862d1f0e15..b0a1d9dfa85c 100644
>> --- a/include/linux/kasan.h
>> +++ b/include/linux/kasan.h
>> @@ -351,6 +351,8 @@ static inline void *kasan_reset_tag(const void *addr)
>> bool kasan_report(unsigned long addr, size_t size,
>> bool is_write, unsigned long ip);
>>
>> +void kasan_report_async(void);
>> +
>> #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
>>
>> static inline void *kasan_reset_tag(const void *addr)
>> diff --git a/mm/kasan/report.c b/mm/kasan/report.c
>> index 234f35a84f19..2fd6845a95e9 100644
>> --- a/mm/kasan/report.c
>> +++ b/mm/kasan/report.c
>> @@ -358,6 +358,17 @@ void kasan_report_invalid_free(void *object, unsigned long ip)
>> end_report(&flags);
>> }
>>
>> +void kasan_report_async(void)
>> +{
>> + unsigned long flags;
>> +
>> + start_report(&flags);
>> + pr_err("BUG: KASAN: invalid-access\n");
>> + pr_err("Asynchronous mode enabled: no access details available\n");
>> + dump_stack();
>> + end_report(&flags);
>> +}
>
> I think the kernel test robot complains that with KASAN_SW_TAGS and
> HW_TAGS disabled, the kasan_report_async() prototype is no longer
> visible but you still have the non-static function definition here. So
> either move kasan_report_async() out of this #ifdef or add the #ifdef
> around the function definition.
>

I think adding #ifdef around the function would be the best way in this case,
for consistency with the header.

> It looks like the original kasan_report() prototype is declared in two
> places (second one in mm/kasan/kasan.h). I'd remove the latter and try
> to have a consistent approach for kasan_report() and
> kasan_report_async().
>

Ok, I will remove it.

--
Regards,
Vincenzo