Re: [PATCH v4 2/6] mounts: keep list of mounts in an rbtree

[Ian Kent]

On 30/10/23 17:06, Miklos Szeredi wrote:
> On Mon, Oct 30, 2023 at 6:45 AM Ian Kent <raven@xxxxxxxxxx> wrote:
>
> > Is fs/namespace.c:iterate_mounts() a problem?
> >
> > It's called from:
> >
> > 1) ./kernel/audit_tree.c:709: if (iterate_mounts(compare_root,
> > 2) ./kernel/audit_tree.c:839:    err = iterate_mounts(tag_mount, tree, mnt);
> > 3) ./kernel/audit_tree.c:917:        failed = iterate_mounts(tag_mount,
> > tree, tagged);
> >
> >
> >   From functions 1) audit_trim_trees(), 2) audit_add_tree_rule() and
> >
> > 3) audit_tag_tree().
> So that interface works like this:
>
>   - collect_mounts() creates a temporary copy of a mount tree, mounts
> are chained on mnt_list.

Right, sorry for the noise, I didn't look far enough.


Ian

>   - iterate_mounts() is used to do some work on the temporary tree
>
>   - drop_collected_mounts() frees the temporary tree
>
> These mounts are never installed in a namespace.  My guess is that a
> private copy is used instead of the original mount tree to prevent
> races.
>
> Thanks,
> Miklos