Re: [RFC PATCH v4 03/12] vfs - move mnt_namespace definition to linux/mount.h

Al Viro
2015-03-20T02:47:45Z

On Thu, Mar 19, 2015 at 08:14:05PM -0500, Eric W. Biederman wrote:

> > Yes please, I'd be more confident if you did this than me, there's
> > already enough to worry about with the series.
>
> Given that this patchset is a security hole waiting to happen I don't
> see why Al should bother unless there are good reasons to do this
> otherwise.

There might be, actually. &...->mnt_ns->ns is a lot saner candidate for
a reference in nsproxy than ...->mnt_ns - *that* is the part nsproxy-related
code cares about anyway, and unlike the rest of struct mnt_namespace it
doesn't have to be opaque for everything outside of (small part of) core
VFS. Additionally, ->mnt_ns is a bad name choice - it sounds like a field
of struct mount and, worse yet, there *is* a field of struct mount with
that name. Confusing for no good reason and makes both harder to grep for.
And current_mnt_ns() is definitely open-coded too many times - the first
commit in that series makes sense regardless of anything else.