On Wed, Nov 07, 2012 at 09:53:02PM +0000, halfdog wrote:
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> Herbert Poetzl wrote:
>> On Wed, Nov 07, 2012 at 04:13:48PM +0000, halfdog wrote: Security
>> testing showed that when an admin enters a vserver guest from
>> interactive shell, a malicious user inside the guest can use this
>> to execute commands on the host. ...
>>> TIOCSTI only works if enabled for a guest (VXC_TIOCSTI) so
>>> unless you have found a bug to circumvent this, I think
>>> Linux-VServer is not affected.
> That's strange, perhaps I made some mistake during testing with
> the packages from repo.psand.net.
what kernel did you use for your tests?
> Is VXC_TIOCSTI enabled by default, how to check that it is
> really disabled.
no, it shouldn't be enabled by default.
you can check it either via 'vattribute --get ...'
or by looking at the CCAPS in 'cat /proc/virtual/<xid>/status'
VXC_TIOCSTI is defined as 0x00000010, so it is bit #4
> And did you try to run the gdb-test?
no, didn't try that yet
> Were there any errors attaching to the process or during exec?
> I'll try to run test-set again from completely fresh setup
> as soon as possible. (or do you have a completely sane test
> environment available?)
new default installation should be sane, but also note that
vserver <name> enter is only intended for emergency maintainance
and not for occasional visits to a running and working guest
(which you should better do via ssh)
in any case, if TIOCSTI is possible inside a guest without
VXC_TIOCSTI enabled, then there is a bug which needs to be fixed
> - --
> 156A AE98 B91F 0114 FE88 2BD8 C459 9386 feed a bee
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Received on Wed Nov 7 23:20:06 2012