Subject: Re: linux-next: manual merge of the akpm-current tree with the userns tree

From: [email-masked] (Eric W. Biederman)
Date: Thu, 26 Jan 2017 13:59:23 +1300

Stephen Rothwell <[email-masked]> writes:

> Hi all,
>
> Today's linux-next merge of the akpm-current tree got a conflict in:
>
>   fs/proc/base.c
>
> between commit:
>
>   68eb94f16227 ("proc: Better ownership of files for non-dumpable tasks in user namespaces")
>
> from the userns tree and commit:
>
>   d15d29b5352f ("procfs: change the owner of non-dumpable and writeable files")
>
> from the akpm-current tree.
>
> I *think* that the former supercedes the latter?

Sort of.  After a long conversation it turns out what they are trying to
do is orthogonal.

The first (mine) is handling the case of non-dumpable tasks in user
namespaces.

The second by Aleksa Sarai is trying to trying to relax the permission
checks in proc so that non-dumpable is not as strict, to sort out some
runC issues where they are having challenges coding themselves into a
corner.  In the case of /proc/self I think there may be a case but in
general relaxing the permission checks in proc gives me the Heebie
Jeebies.

Andrew do you see merit in Aleksa's patch that I don't?  Otherwise can
you remove it from your tree?

> I fixed it up (I just used the former) and can carry the fix as
> necessary. This is now fixed as far as linux-next is concerned, but any
> non trivial conflicts should be mentioned to your upstream maintainer
> when your tree is submitted for merging.  You may also want to consider
> cooperating with the maintainer of the conflicting tree to minimise any
> particularly complex conflicts.

Stephen thank you for pointing this out.

Eric