NFSv2 directory cannot longer be exported in 3.14, 3.13 works fine

DISCUSSION Toralf Förster 2 participants 4 messages Apr 4, 2014 – Apr 5, 2014

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Toralf Förster

author

2014-04-04 21:57 UTC #0 lore raw

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At a user mode linux image (32 bit Gentoo Linux) the recent kernel gives this error while trying to mount a NFSv2 directory:
mount.nfs: mount point /mnt/nfsv2 is not a directory

The hostname is n22stab4, contents of the files follows.

/etc/fstab:

tmpfs                   /mnt/ramdisk    tmpfs   auto,size=300M
n22stab4:/mnt/ramdisk   /mnt/nfsv2      nfs     auto,bg,intr,soft,nfsvers=2

/etc/exports:
/mnt/ramdisk 192.168.0.0/16(rw,fsid=0,insecure,no_subtree_check,async,no_root_squash)

/var/log/messages:

Apr  4 23:55:45 n22stab4 kernel: init_special_inode: bogus i_mode (1777) for inode 0:24:818

- --
MfG/Sincerely
Toralf Förster
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Toralf Förster

author

2014-04-05 12:17 UTC #1 lore raw

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Quoted 3 lines · Toralf Förster

At a user mode linux image (32 bit Gentoo Linux) the recent kernel gives this error while trying to mount a NFSv2 directory:
mount.nfs: mount point /mnt/nfsv2 is not a directory

A bisect points to :

6e14b46b91fee8a049b0940333ce13a820beaaa5 is the first bad commit commit 6e14b46b91fee8a049b0940333ce13a820beaaa5

Author: Albert Fluegel <[email protected]>
Date:   Mon Nov 18 12:18:01 2013 -0500

nfsd: don't return high mode bits

The Linux NFS server replies among other things to a "Check access permission" the following:

NFS: File type = 2 (Directory)
NFS: Mode = 040755

A netapp server replies here:
NFS: File type = 2 (Directory)
NFS: Mode = 0755

The RFC 1813 i read:
fattr3

struct fattr3 {
ftype3 type;
mode3 mode;
uint32 nlink;
...
For the mode bits only the lowest 9 are defined in the RFC

As far as I can tell, knfsd has always done this, so apparently it's harmless. Nevertheless, it appears to be wrong.

Note this is already correct in the NFSv4 case, only v2 and v3 need fixing.

Signed-off-by J. Bruce Fields <[email protected]>

:040000 040000 a60e55f5a9749db3977e12e8baa08d45fadba225 b982c02ec1069c5d969ccb71197e5569fe93b075 M fs

iF4EAREIAAYFAlM/9FcACgkQxOrN3gB26U5F1AD+JAP4cDM+rT9nk9Q8q681RywT Ejxq7d0tnVUfWyDFDTgA/1sIUtpv9GSK8SeAJFu7oAhMt4e6eeIdbpMT2qUEQv6q =Sles
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Jeff Layton

2014-04-05 12:51 UTC #2 lore raw

Quoted 55 lines · On Sat, 05 Apr 2014 14:17:27 +0200 Toralf Förster <[email protected]>…

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Hash: SHA256
Quoted 3 lines · Toralf Förster
At a user mode linux image (32 bit Gentoo Linux) the recent kernel gives this error while trying to mount a NFSv2 directory:
mount.nfs: mount point /mnt/nfsv2 is not a directory
A bisect points to :
6e14b46b91fee8a049b0940333ce13a820beaaa5 is the first bad commit commit 6e14b46b91fee8a049b0940333ce13a820beaaa5
Author: Albert Fluegel <[email protected]>
Date:   Mon Nov 18 12:18:01 2013 -0500
nfsd: don't return high mode bits
The Linux NFS server replies among other things to a "Check access permission" the following:
NFS: File type = 2 (Directory)
NFS: Mode = 040755
A netapp server replies here:
NFS: File type = 2 (Directory)
NFS: Mode = 0755
The RFC 1813 i read:
fattr3
struct fattr3 {
ftype3 type;
mode3 mode;
uint32 nlink;
...
For the mode bits only the lowest 9 are defined in the RFC
As far as I can tell, knfsd has always done this, so apparently it's harmless. Nevertheless, it appears to be wrong.
Note this is already correct in the NFSv4 case, only v2 and v3 need fixing.
Signed-off-by J. Bruce Fields <[email protected]>
:040000 040000 a60e55f5a9749db3977e12e8baa08d45fadba225 b982c02ec1069c5d969ccb71197e5569fe93b075 M fs
- --
MfG/Sincerely
Toralf Förster
pgp finger print:1A37 6F99 4A9D 026F 13E2 4DCF C4EA CDDE 0076 E94E -----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
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Quoted 8 lines

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This was already tracked down earlier this week. Bruce has a patch queued to fix it in his nfsd-next branch. See this thread from earlier this week:

Subject: Re: linux-3.14 nfsd regression

Signature · 1 line

Jeff Layton <[email protected]>

Toralf Förster

author

2014-04-05 13:23 UTC #3 lore raw

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Quoted 5 lines · Jeff Layton

This was already tracked down earlier this week. Bruce has a patch queued to fix it in his nfsd-next branch. See this thread from earlier this week:
Subject: Re: linux-3.14 nfsd regression

yep - fixed the issue here

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