Message-ID: <ecfe32fc-f547-ca7f-dc07-018af4d23f39@redhat.com>
Date:   Sun, 12 Mar 2023 10:20:50 -0400
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Subject: Re: mountd: Possible bug in next_mnt()
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To:     Richard Weinberger <richard@nod.at>
Cc:     linux-nfs <linux-nfs@vger.kernel.org>,
        trond myklebust <trond.myklebust@hammerspace.com>,
        chris chilvers <chris.chilvers@appsbroker.com>
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From:   Steve Dickson <steved@redhat.com>
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On 3/12/23 9:36 AM, Richard Weinberger wrote:
> ----- Ursprüngliche Mail -----
>> On 3/11/23 11:52 AM, Richard Weinberger wrote:
>>> ----- Ursprüngliche Mail -----
>>>>> next_mnt() finds submounts below a given path p.
>>>>> While investigating into an issue in my crossmount patches for nfs-utils I
>>>>> noticed
>>>>> that it does not work when fsid=root, rootdir=/some/path/ and then "/" is being
>>>>> exported.
>>>>> In this case next_mnt() is asked to find submounts of "/" but returns none.
>>>> I'm not clear as what you are saying... "rootdir=/some/path/" is not an
>>>> export option.
>>>
>>> Sorry for being imprecise.
>>> rootdir= is an nfs.conf exports option.Point. But I still need the patch in the
>>> correct
>> format with the Signed-off-by...
> 
> Well, the goal of my mail was not sending a ready-to-apply patch.
> It was a question. To me next_mnt() looks wrong but I'm not sure whether
> the current handling of "/" is desired for some special case I'm not aware of.
> 
> I'll happily send a patch after we agree that next_mnt() is wrong.
I'm still trying to reproduce problem... I have

/etc/nfs.conf: rootdir=/export

/etc/exports:
/home *(rw,sec=sys:krb5:krb5i:krb5p)
/tmp *(rw,fsid=666,all_squash)
/ *(rw,fsid=root,all_squash)

I'm not seeing the problem... Where does the crossmount come in?

steved.