linux-kernel - Re: [RFC] [PATCH 1/7] User Space Breakpoint Assistance Layer (UBP)

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: <1263800752.4283.19.camel@laptop>
Date:	Mon, 18 Jan 2010 08:45:52 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Avi Kivity <avi@...hat.com>
Cc:	ananth@...ibm.com, Jim Keniston <jkenisto@...ibm.com>,
	Srikar Dronamraju <srikar@...ux.vnet.ibm.com>,
	Ingo Molnar <mingo@...e.hu>,
	Arnaldo Carvalho de Melo <acme@...radead.org>,
	utrace-devel <utrace-devel@...hat.com>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Masami Hiramatsu <mhiramat@...hat.com>,
	Maneesh Soni <maneesh@...ibm.com>,
	Mark Wielaard <mjw@...hat.com>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [RFC] [PATCH 1/7] User Space Breakpoint Assistance Layer (UBP)

On Sun, 2010-01-17 at 21:33 +0200, Avi Kivity wrote:
> On 01/17/2010 05:03 PM, Peter Zijlstra wrote:
> >
> >> btw, an alternative is to require the caller to provide the address
> >> space for this.  If the caller is in another process, we need to allow
> >> it to play with the target's address space (i.e. mmap_process()).  I
> >> don't think uprobes justifies this by itself, but mmap_process() can be
> >> very useful for sandboxing with seccomp.
> >>      
> > mmap_process() sounds utterly gross, one process playing with another
> > process's address space.. yuck!
> >    
> 
> This is debugging.  We're playing with registers, we're playing with the 
> cpu, we're playing with memory contents.  Why not the address space as well?

Because you want thins go to be as transparent as possible in order to
avoid heisenbugs. Sure we cannot avoid everything, but we should avoid
everything we possibly can.

Also, aside of the VDSO, we simply do not force map things into address
spaces (and like said before, I think the VDSO stinks for doing that)
and I think we don't want to create (more) precedents in this case.



--
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/