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Date:   Thu, 20 Jan 2022 13:24:09 +0100
From:   Petr Vorel <pvorel@suse.cz>
To:     NeilBrown <neilb@suse.de>
Cc:     linux-nfs@vger.kernel.org,
        "J. Bruce Fields" <bfields@fieldses.org>,
        Chuck Lever <chuck.lever@oracle.com>,
        Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <anna.schumaker@netapp.com>,
        Steve Dickson <SteveD@redhat.com>,
        Nikita Yushchenko <nikita.yushchenko@virtuozzo.com>,
        ltp@lists.linux.it
Subject: Re: LTP nfslock01 test failing on NFS v3 (lockd: cannot monitor
 10.0.0.2)
Message-ID: <YelUaQHlCp8FHAeQ@pevik>
Reply-To: Petr Vorel <pvorel@suse.cz>
References: <YebcNQg0u5cU1QyQ@pevik>
 <164254391708.24166.6930987548904227011@noble.neil.brown.name>
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In-Reply-To: <164254391708.24166.6930987548904227011@noble.neil.brown.name>
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Hi Neil, all,

> On Wed, 19 Jan 2022, Petr Vorel wrote:
> > Hi all,

> > this is a test failure posted by Nikita Yushchenko [1]. LTP NFS test nfslock01
> > looks to be failing on NFS v3:

> > "not unsharing /var makes AF_UNIX socket for host's rpcbind to become available
> > inside ltpns. Then, at nfs3 mount time, kernel creates an instance of lockd for
> > ltpns, and ports for that instance leak to host's rpcbind and overwrite ports
> > for lockd already active for root namespace. This breaks nfs3 file locking."

> "not unsharing /var" ....  can this be fixed by simply unsharing /var?
> Or is that not simple?

> On could easily argue that RPCBIND_SOCK_PATHNAME in the kernel should be
> changed to "/run/rpcbind.sock".  Does this test suite unshare /run ??

> BTW, your email contains [1], [2], etc which suggests there are links
> somewhere - but there aren't.
I'm sorry, here they are:

[1] https://lore.kernel.org/ltp/590378ee-71af-deb6-6c03-1d2af459ed63@virtuozzo.com/
(the report)

[2] https://lore.kernel.org/ltp/20220112161942.4065665-1-nikita.yushchenko@virtuozzo.com/
(the not yet merged LTP Nikita's patch)

[3] https://github.com/pevik/ltp/commits/nfs_flock/fail-on-error
(my LTP fork with Nikita's patch [2] + strace debugging - with this code I post
the report)

Kind regards,
Petr

> NeilBrown