linux-kernel - Re: [PATCH] [RFC] Deter exploit bruteforcing

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20150102222936.GA29018@amd>
Date:	Fri, 2 Jan 2015 23:29:36 +0100
From:	Pavel Machek <pavel@....cz>
To:	Richard Weinberger <richard@....at>
Cc:	Kees Cook <keescook@...omium.org>,
	LKML <linux-kernel@...r.kernel.org>,
	"linux-fsdevel@...r.kernel.org" <linux-fsdevel@...r.kernel.org>,
	David Rientjes <rientjes@...gle.com>,
	Aaron Tomlin <atomlin@...hat.com>,
	DaeSeok Youn <daeseok.youn@...il.com>,
	Thomas Gleixner <tglx@...utronix.de>, vdavydov@...allels.com,
	Rik van Riel <riel@...hat.com>,
	Oleg Nesterov <oleg@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Al Viro <viro@...iv.linux.org.uk>,
	Andy Lutomirski <luto@...capital.net>,
	Brad Spengler <spender@...ecurity.net>
Subject: Re: [PATCH] [RFC] Deter exploit bruteforcing

On Fri 2015-01-02 22:40:14, Richard Weinberger wrote:
> Am 02.01.2015 um 20:46 schrieb Pavel Machek:
> >>> Does this break trinity, crashme, and similar programs?
> >>
> >> If they fork() without execve() and a child dies very fast the next fork()
> >> will be throttled.
> >> This is why I'd like to make this feature disabled by default.
> >>
> >>> Can you detect it died due to the stack canary? Then, the patch might
> >>> be actually acceptable.
> >>
> >> I don't think so as this is glibc specific.
> > 
> > Can the slowdown be impelmented in glibc, then?
> 
> glibc has a lot of asserts where it can detect stack smashing and kills the
> current process using abort(). Here it could of course also call
> sleep().

Please do it in glibc, then.

> > If not, can glibc provide enough information to the kernel to allow us
> > to do the right thing?
> 
> IMHO we should not strictly focus on the stack canary.

IMO we should. We want it enabled by default.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
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/