On 12/14/2011 06:56 PM, Paul Moore wrote:
On Wednesday, December 14, 2011 11:15:58 AM Serge E. Hallyn wrote:
Quoting Paul Moore (pmo...@redhat.com):
On Wednesday, December 07, 2011 12:48:16 PM Anthony Liguori wrote:
On 12/07/2011 12:25 PM, Corey Bryant wrote:
A group of us are starting to work on sandboxing QEMU device
emulation code. We're just getting started investigating
various approaches, and want to engage the community to gather
input.
Following are the design points that we are currently considering:
To be perfectly honest, I think prototyping and measuring
performance is going to be the only way to figure out the right
approach here.>
Agreed. I'm currently working on a prototype to play around with some
of the ideas discussed in this thread. As soon as it is functional
I'll send a pointer/patches/etc. to the list.
Hey Paul,
just wondering, exactly which approache(s) are you prototyping? Are you
touching seccomp2?
The decomposed approach as I felt (well, still do for that matter) that the
enhanced seccomp stuff could be put to even better use in a decomposed mode of
operation.
However, earlier this week those of us involved in this effort were strongly
discouraged (this probably isn't the best term to use, but there is a reason
I'm a programmer and not an english student) from pursuing the decomposed
prototype further so work on it has dropped off considerably.
I still think it is worth pursuing, if for no other reason than to answer
questions that right now we can only answer with educated guesses, but it is
no longer my main focus. If anyone else is interested in this feel free to
drop me some email and I can bring you up to speed on the current status.
As far as the enhanced seccomp patches for QEMU, I believe Corey said that IBM
was starting work on a prototype based on the patches that Will posted earlier
this year. I don't expect this change to be very substantial, the hard part
will be determining the syscall filter and maintaining it over time.
Paul covered the current state of affairs above so I won't expand on
that much. One of the major concerns from the QEMU community revolved
around the maintenance complexity introduced by decomposing QEMU into
separate processes, and that patches doing so were unlikely to be accepted.
With that in mind we're going to pursue a single process mode 2
approach. We'll put together a trivial prototype for evaluation
purposes. Like Paul mentioned, one of the complex parts is determining
the correct call parameter filters, and there will be tweaking required
as new syscalls/parameters are introduced in the future. But the
biggest hurdle is getting mode 2 patches into the mainline kernel, which
has been an unsuccessful effort for a few years now.
--
Regards,
Corey
