linux-kernel - Re: [PATCH v4 3/5] kasan: Add report for async mode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <d9ee1147-be64-4910-aca5-6b83f1c71895@arm.com>
Date:   Wed, 20 Jan 2021 14:46:44 +0000
From:   Vincenzo Frascino <vincenzo.frascino@....com>
To:     Andrey Konovalov <andreyknvl@...gle.com>,
        Mark Rutland <mark.rutland@....com>
Cc:     Catalin Marinas <catalin.marinas@....com>,
        Branislav Rankov <Branislav.Rankov@....com>,
        Marco Elver <elver@...gle.com>,
        Evgenii Stepanov <eugenis@...gle.com>,
        LKML <linux-kernel@...r.kernel.org>,
        kasan-dev <kasan-dev@...glegroups.com>,
        Alexander Potapenko <glider@...gle.com>,
        Linux ARM <linux-arm-kernel@...ts.infradead.org>,
        Andrey Ryabinin <aryabinin@...tuozzo.com>,
        Will Deacon <will@...nel.org>,
        Dmitry Vyukov <dvyukov@...gle.com>
Subject: Re: [PATCH v4 3/5] kasan: Add report for async mode


On 1/19/21 6:12 PM, Andrey Konovalov wrote:
> On Tue, Jan 19, 2021 at 3:46 PM Mark Rutland <mark.rutland@....com> wrote:
>>
>> Given there's no information available, I think it's simpler and
>> preferable to handle the logging separately, as is done for
>> kasan_report_invalid_free(). For example, we could do something roughly
>> like:
>>
>> void kasan_report_async(void)
>> {
>>         unsigned long flags;
>>
>>         start_report(&flags);
>>         pr_err("BUG: KASAN: Tag mismatch detected asynchronously\n");
> 
> "BUG: KASAN: invalid-access"
>

Ok, I will do in v5. It looks more uniform with what we have for the sync exception.

> It also might make sense to pass the ip, even though it's not exactly
> related to the access:
> 

I would like to avoid to add a builtin for something that has not a real meaning
as you are correctly pointing out.

> pr_err("BUG: KASAN: invalid-access in %pS\n", (void *)ip);
> 
> Up to you.
> 
>>         pr_err("KASAN: no fault information available\n");
> 
> pr_err("Asynchronous mode enabled: no access details available\n");
> 
>>         dump_stack();
>>         end_report(&flags);
>> }
> 
> This approach with a dedicated function is better. Thanks, Mark!
> 
> Please put it next to kasan_report_invalid_free().
> 

Will do in v5.

Thanks!

-- 
Regards,
Vincenzo