linux-kernel - Re: [GIT PULL] gcc-plugins updates for v4.13-rc1

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]

Date:   Wed, 5 Jul 2017 14:52:34 -0700
From:   Kees Cook <keescook@...omium.org>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     Linus Torvalds <torvalds@...ux-foundation.org>,
        Ard Biesheuvel <ard.biesheuvel@...aro.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Jean Delvare <jdelvare@...e.de>
Subject: Re: [GIT PULL] gcc-plugins updates for v4.13-rc1

On Wed, Jul 5, 2017 at 2:48 PM, Arnd Bergmann <arnd@...db.de> wrote:
> On Wed, Jul 5, 2017 at 11:35 PM, Linus Torvalds
> <torvalds@...ux-foundation.org> wrote:
>
>> So the issue I think would be good to fix is perhaps best explained by
>> pseudo-code
>>
>>   int testfn(struct somestruct __user *p)
>>   {
>>         struct somestruct a;
>>
>>         initialize_struct(&a);
>>         if (copy_to_user(p, &a, sizeof(a)))
>>                 return -EFAULT;
>>         return 0;
>>   }
>>
>> which is obviously made-up code, but is not actually entirely unrealistic.
>
> This particular example should be handled by
> scripts/gcc-plugins/structleak_plugin.c, right?

Only if struct somestruct _contains_ a __user pointer. I would love to
see this logic expanded, of course. :)

-Kees

-- 
Kees Cook
Pixel Security