[PATCH 00/14] Make the user mode driver code a better citizen

[Alexei Starovoitov]

On Fri, Jun 26, 2020 at 07:51:41AM -0500, Eric W. Biederman wrote:
> 
> Asking for people to fix their bugs in this user mode driver code has
> been remarkably unproductive.  So here are my bug fixes.
> 
> I have tested them by booting with the code compiled in and
> by killing "bpfilter_umh" and running iptables -vnL to restart
> the userspace driver.
> 
> I have split the changes into small enough pieces so they should be
> easily readable and testable.  
> 
> The changes lean into the preexisting interfaces in the kernel and
> remove special cases for user mode driver code in favor of solutions
> that don't need special cases.  This results in smaller code with
> fewer bugs.
> 
> At a practical level this removes the maintenance burden of the
> user mode drivers from the user mode helper code and from exec as
> the special cases are removed.
> 
> Similarly the LSM interaction bugs are fixed by not having unnecessary
> special cases for user mode drivers.
> 
> Please let me know if you see any bugs.  Once the code review is
> finished I plan to take this through my tree.

I did a quick look and I like the cleanup. Thanks! The end result looks good.
The only problem that you keep breaking the build between patches,
so series will not be bisectable.
blob_to_mnt is a great idea. Much better than embedding fs you advocated earlier.

I'm swamped with other stuff today and will test the set Sunday/Monday
with other patches that I'm working on.
I'm not sure why you want to rename the interface. Seems pointless. But fine.

As far as routing trees. Do you mind I'll take it via bpf-next ?
As I said countless times we're working on bpf_iter using fork_blob.
If you take this set via your tree we would need to wait the whole kernel release.
Which is 8+ weeks before we can use the interface (due to renaming and overall changes).
I'd really like to avoid this huge delay.
Unless you can land it into 5.8-rc2 or rc3.