linux-kernel - Re: [PATCH 11/11] protect architectures where THREAD_SIZE >= PAGE

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: <alpine.DEB.2.00.1206252157000.30072@chino.kir.corp.google.com>
Date:	Mon, 25 Jun 2012 21:57:54 -0700 (PDT)
From:	David Rientjes <rientjes@...gle.com>
To:	Glauber Costa <glommer@...allels.com>
cc:	cgroups@...r.kernel.org, linux-mm@...ck.org,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org,
	Frederic Weisbecker <fweisbec@...il.com>,
	Pekka Enberg <penberg@...nel.org>,
	Michal Hocko <mhocko@...e.cz>,
	Johannes Weiner <hannes@...xchg.org>,
	Christoph Lameter <cl@...ux.com>, devel@...nvz.org,
	kamezawa.hiroyu@...fujitsu.com, Tejun Heo <tj@...nel.org>,
	Pekka Enberg <penberg@...helsinki.fi>,
	Suleiman Souhlal <suleiman@...gle.com>,
	Frederic Weisbecker <fweisbec@...hat.com>
Subject: Re: [PATCH 11/11] protect architectures where THREAD_SIZE >= PAGE_SIZE
 against fork bombs

On Mon, 25 Jun 2012, Glauber Costa wrote:

> diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
> index ccc1899..914ec07 100644
> --- a/include/linux/thread_info.h
> +++ b/include/linux/thread_info.h
> @@ -61,6 +61,12 @@ extern long do_no_restart_syscall(struct restart_block *parm);
>  # define THREADINFO_GFP		(GFP_KERNEL | __GFP_NOTRACK)
>  #endif
>  
> +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
> +# define THREADINFO_GFP_ACCOUNTED (THREADINFO_GFP | __GFP_KMEMCG)
> +#else
> +# define THREADINFO_GFP_ACCOUNTED (THREADINFO_GFP)
> +#endif
> +

This type of requirement is going to become nasty very quickly if nobody 
can use __GFP_KMEMCG without testing for CONFIG_CGROUP_MEM_RES_CTLR_KMEM.  
Perhaps define __GFP_KMEMCG to be 0x0 if it's not enabled, similar to how 
kmemcheck does?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/