oss-sec mailing list archives
Re: CVE Request: linux-kernel priviledge escalation on ARM/perf
From: Petr Matousek <pmatouse () redhat com>
Date: Fri, 16 Aug 2013 13:07:49 +0200
On Wed, Aug 14, 2013 at 05:37:32PM -0400, Vince Weaver wrote:
Hello I'm not really a security researcher, so hopefully I'm reporting this in the proper way.
Thank you for the report, Vince. I think that it is completely fine -)
I have a fuzzer tool for the perf_event_open() syscall that found a few oopses on the ARM platform, which I reported to lkml a week ago. One of the oopses can lead to a local privilege escalation on ARM-perf. This fix can be found here: http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=7809/1 The discussion thread is: https://lkml.org/lkml/2013/8/7/259 The hope is this appears in 3.11-rc6 but my attempts to get the people at security () vger kernel org to take this seriously didn't really go very well. I do have code that will exploit the kernel and give me a root shell on an ARM Pandaboard machine running 3.11-rc4. The exploit is a bit fragile though: + Only works on ARM + Elevates from normal user to root, no special config required. perf_event syscalls run as regular users, not sure why some think you need root. + It does need a user-mappable address at an exact byte offset from a pmu_struct in memory. This limits things somewhat; in my testing 3.11-rc kernels have INT_MIN at exactly the right place but the exploit doesn't work on a 3.7.6 kernel, it just oopses or crashes the machine.
This looks valid to me. Unless someone has any objections, can you please Kurt assign CVE to this issue? Thanks, -- Petr Matousek / Red Hat Security Response Team
Current thread:
- CVE Request: linux-kernel priviledge escalation on ARM/perf Vince Weaver (Aug 14)
- Re: CVE Request: linux-kernel priviledge escalation on ARM/perf Petr Matousek (Aug 16)
- Re: CVE Request: linux-kernel priviledge escalation on ARM/perf Kurt Seifried (Aug 16)
- Re: CVE Request: linux-kernel priviledge escalation on ARM/perf Vince Weaver (Aug 20)
- Re: CVE Request: linux-kernel priviledge escalation on ARM/perf Petr Matousek (Aug 16)