linux-kernel - Re: [x86/uaccess] 5b710f34e1: kernel BUG at mm/usercopy.c:75!

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: <CA+55aFztyqMH5DJXVGdjbsaGKnNCyG4kYaicvqNeNF3=oVmuhQ@mail.gmail.com>
Date:	Wed, 17 Aug 2016 14:55:21 -0700
From:	Linus Torvalds <torvalds@...ux-foundation.org>
To:	Kees Cook <keescook@...omium.org>
Cc:	Rik van Riel <riel@...hat.com>,
	kernel test robot <xiaolong.ye@...el.com>, LKP <lkp@...org>,
	LKML <linux-kernel@...r.kernel.org>,
	Valdis Kletnieks <valdis.kletnieks@...edu>
Subject: Re: [x86/uaccess] 5b710f34e1: kernel BUG at mm/usercopy.c:75!

On Wed, Aug 17, 2016 at 2:50 PM, Kees Cook <keescook@...omium.org> wrote:
> On Wed, Aug 17, 2016 at 2:45 PM, Linus Torvalds
>>
>> Networking does, but seems to use __GFP_COMP, at least in the one case
>> I checked (skbuff).
>
> Was this allocation really through kmalloc?

The networking one I looked at, no. But they do __GFP_COMP.

The task struct allocation generally is (alloc_task_struct_node()),
but as Rik pointed out, SLOB doesn't actually necessarily do the slab
book-keeping for multi-page allocations.

               Linus