On Thu, 2018-11-01 at 04:51 +0100, Jann Horn wrote: > On Thu, Nov 1, 2018 at 3:59 AM James Bottomley > <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote: > > > > On Tue, 2018-10-16 at 11:52 +0200, Laurent Vivier wrote: > > > Hi, > > > > > > Any comment on this last version? > > > > > > Any chance to be merged? > > > > I've got a use case for this: I went to one of the Graphene talks > > in Edinburgh and it struck me that we seem to keep reinventing the > > type of sandboxing that qemu-user already does. However if you > > want to do an x86 on x86 sandbox, you can't currently use the > > binfmt_misc mechanism because that has you running *every* binary > > on the system emulated. Doing it per user namespace fixes this > > problem and allows us to at least cut down on all the pointless > > duplication. > > Waaaaaait. What? qemu-user does not do "sandboxing". qemu-user makes > your code slower and *LESS* secure. As far as I know, qemu-user is > only intended for purposes like development and testing. Sandboxing is about protecting the cloud service provider (and other tenants) from horizontal attack by reducing calls to the shared kernel. I think it's pretty indisputable that full emulation is an effective sandbox in that regard. We can argue for about bugginess vs completeness, but technologically qemu-user already has most of the system calls, which seems to be a significant problem with other sandboxes. I also can't dispute it's slower, but that's a tradeoff for people to make. James
