Re: [PATCH v2] nfsd: fix net-namespace logic in __nfsd_file_cache_purge

Petr Vorel
2022-10-31T18:45:08Z

> > On Oct 31, 2022, at 11:49 AM, Jeff Layton <jlayton@kernel.org> wrote:

> > If the namespace doesn't match the one in "net", then we'll continue,
> > but that doesn't cause another rhashtable_walk_next call, so it will
> > loop infinitely.

> > Fixes: ce502f81ba88 ("NFSD: Convert the filecache to use rhashtable")
> > Reported-by: Petr Vorel <pvorel@suse.cz>
> > Signed-off-by: Jeff Layton <jlayton@kernel.org>
> > ---
> > fs/nfsd/filecache.c | 5 ++---
> > 1 file changed, 2 insertions(+), 3 deletions(-)

> Thank you! Applied and pushed to for-rc. I'll send a PR in a few days.

Thanks for a quick action!

What a shame you didn't put link to the report, which contains reproducer.
https://lore.kernel.org/ltp/Y1%2FP8gDAcWC%2F+VR3@pevik/

Kind regards,
Petr

> > The v1 patch applies cleanly to v6.0, but not to Chuck's for-next
> > branch. This one should be suitable there.
> > diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
> > index 98c6b5f51bc8..4a8aa7cd8354 100644
> > --- a/fs/nfsd/filecache.c
> > +++ b/fs/nfsd/filecache.c
> > @@ -890,9 +890,8 @@ __nfsd_file_cache_purge(struct net *net)

> > nf = rhashtable_walk_next(&iter);
> > while (!IS_ERR_OR_NULL(nf)) {
> > - if (net && nf->nf_net != net)
> > - continue;
> > - nfsd_file_unhash_and_dispose(nf, &dispose);
> > + if (!net || nf->nf_net == net)
> > + nfsd_file_unhash_and_dispose(nf, &dispose);
> > nf = rhashtable_walk_next(&iter);
> > }

> > --
> > 2.38.1