Re: [PATCH 0/5] RDMA: reg_remote_mr

[Joel Nider]

Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx> wrote on 01/29/2019 06:44:48 PM:

> 
> On 1/29/2019 7:26 AM, Joel Nider wrote:
> > As discussed at LPC'18, there is a need to be able to register a 
memory
> > region (MR) on behalf of another process. One example is the case of
> > post-copy container migration, in which CRIU is responsible for 
setting
> > up the migration, but the contents of the memory are from the 
migrating
> > process. In this case, we want all RDMA READ requests to be served by
> > the address space of the migration process directly (not by CRIU). 
This
> > patchset implements a new uverbs command which allows an application 
to
> > register a memory region in the address space of another process.
> 
> Hey Joel,
> 
> Dumb question:
> 
> Doesn't this open a security hole by allowing any process to register
> memory in any other process?

Not a dumb question - there is a security problem. Jason just suggested
I look at how ptrace solves the problem, so that's my best option at the
moment. Still, I figured it was a good idea to let everyone take a look
at what I have so far, and start to get feedback.

> Steve.
> 
>