On 05/15/2013 09:11 PM, richard -rw- weinberger wrote:
> On Wed, May 15, 2013 at 9:06 PM, Toralf Förster <[email protected]>
> wrote:
>> On 05/13/2013 09:12 AM, richard -rw- weinberger wrote:
>>> This looks like another issue.
>>> Are you testing process_vm_writev() with trinity?
>>> Looks like it managed to overwrite the stub page of a process, which
>>> is not good.
>> nope, it is the mremap syscall.
>>
>> A command like
>>
>> $>trinity -c mremap -N 10
>>
>> immediately after starting a 32 bit Gentoo linux guest with current kernel
>> 3.10-rc1-... +
>> strnlen + stub4 patch works, but later a
>>
>> $>trinity -c mremap -N 1000
>>
>> yields into
>>
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: Stub registers -
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 0 - 100000
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 1 - 300000
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 2 - 0
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 3 - 0
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 4 - 0
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 5 - 0
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 6 - 0
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 7 - 7b
>> 2013-05-15T21:02:04.061+02:00 trinity kernel: 8 - 7b
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: 9 - 0
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: 10 - 33
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: 11 - ffffffff
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: 12 - 1000c3
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: 13 - 73
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: 14 - 10206
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: 15 - 101028
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: 16 - 7b
>> 2013-05-15T21:02:04.065+02:00 trinity kernel: wait_stub_done : failed to
>> wait for SIGTRAP, pid = 15692, n = 15692, errno = 0, status = 0xb7f
>>
>> and now that process can't be killed - I had to stop the UML guest.
>
> Hmm, you've remapped the stub page and therefore the process broke.
> I think it would make sense to kill the process in stead of writing
> the "wait_stub_done ..." message.
> Changing the stub page is as destructive than overwriting the stack.
Unfortunately no trinity process can be killed as soon as that happen.
Neither pgrep, pkill, nor "ps -efla" do return any result.
Killing any of those processes by its pid won't work too.
> Maybe we can teach triniy to no change the stub page.
> I'm sure trinity has also a mechanism to not destroy the stack.
@trinity Mailing list
What do you think about that ?
--
MfG/Sincerely
Toralf Förster
pgp finger print: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 7DB6 9DA3
------------------------------------------------------------------------------
AlienVault Unified Security Management (USM) platform delivers complete
security visibility with the essential security capabilities. Easily and
efficiently configure, manage, and operate all of your security controls
from a single console and one unified framework. Download a free trial.
http://p.sf.net/sfu/alienvault_d2d
_______________________________________________
User-mode-linux-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
