linux-kernel - Re: [EXAMPLE CODE] Parasite thread injection and TCP connection hijacking

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: <20110806130037.GD23937@htj.dyndns.org>
Date:	Sat, 6 Aug 2011 15:00:37 +0200
From:	Tejun Heo <tj@...nel.org>
To:	Andy Lutomirski <luto@....EDU>
Cc:	Matt Helsley <matthltc@...ibm.com>,
	Pavel Emelyanov <xemul@...allels.com>,
	Nathan Lynch <ntl@...ox.com>,
	Oren Laadan <orenl@...columbia.edu>,
	Daniel Lezcano <dlezcano@...ibm.com>, S@....edu,
	"James E.J. Bottomley" <JBottomley@...allels.com>,
	"David S. Miller" <davem@...emloft.net>,
	linux-kernel@...r.kernel.org, netdev@...r.kernel.org
Subject: Re: [EXAMPLE CODE] Parasite thread injection and TCP connection
 hijacking

Hello,

On Sat, Aug 06, 2011 at 08:45:28AM -0400, Andy Lutomirski wrote:
> > 2. Decide where to inject the foreign code and save the original code
> >    with PTRACE_PEEKDATA.  Tracer can poke any mapped area regardless
> >    of protection flags but it can't add execution permission to the
> >    code, so it needs to choose memory area which already has X flag
> >    set.  The example code uses the page the %rip is in.
> 
> If the process is executing from the vsyscall page, then you'll
> probably fail.  (Admittedly, this is rather unlikely, given that the
> vsyscalls are now exactly one instruction.)  Presumably you also
> fail if executing from a read-only MAP_SHARED mapping.

Heh, yeah, I originally thought about scanning /proc/PID/maps to look
for the page to use but was lazy and just used %rip.  I think that
should work.  I'll note the problem in README.

> Windows has a facility to more-or-less call mmap on behalf of
> another process, and another one to directly inject a thread into a
> remote process.  It's traditional to use them for this type of
> manipulation. Perhaps Linux should get the same thing.  (Although
> you could accomplish much the same thing if you could create a task
> with your mm but the tracee's fs.)

Actually, the only thing we need on x86_64 is two bytes for the
syscall instruction because all params are passed through registers
anyway.  We can just set up parameters for mmap, turn on single step,
point %rip to syscall in the vsyscall page.  So, either way, I don't
think this would be too difficult to solve.

Thanks.

-- 
tejun
--
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/