[Samba] dfs links anywhere?

[Aurélien Aptel]

(Let's keep this on the list)

Aurélien Aptel via samba <samba at lists.samba.org> writes:
> Chad William Seys <cwseys at physics.wisc.edu> writes:
>> Somehow the destination having 'msdfsroot yes' prevents the cifs kernel 
>> module from following the link.

I've taken a look at your traces and right off the bat I see things like
this:

[...] /linux-4.9.30/fs/cifs/smb1ops.c: cifs_query_symlink: target path: \smb03.physics.wisc.edu\smb\instr_files
[...] /linux-4.9.30/fs/cifs/link.c: CIFS VFS: leaving cifs_get_link (xid = 35208) rc = 0
[...] /linux-4.9.30/fs/cifs/dir.c: CIFS VFS: in cifs_lookup as Xid: 35209 with uid: 1494
[...] /linux-4.9.30/fs/cifs/dir.c: parent inode = 0xffff893b14d610a8 name is: \smb03.physics.wisc.edu\smb\instr_files and dentry = 0xffff893b79dda3c0
[...] /linux-4.9.30/fs/cifs/dir.c: name: /\smb03.physics.wisc.edu\smb\instr_files
[...] /linux-4.9.30/fs/cifs/dir.c: name: /itadmin/\smb03.physics.wisc.edu\smb\instr_files
[...] /linux-4.9.30/fs/cifs/dir.c: NULL inode in lookup
[...] /linux-4.9.30/fs/cifs/dir.c: Full path: //smb.physics.wisc.edu/smb/itadmin/\smb03.physics.wisc.edu\smb\instr_files inode = 0x          (null)

Note the weird looking path:

  //smb.physics.wisc.edu/smb/itadmin/\smb03.physics.wisc.edu\smb\instr_files

Look to me the link is not properly substituted and there might some
issues with Unix Extensions mixing path separators.

I couldn't reproduce this on recent master kernel but I'll give it a try
on v4.9 which you seem to be using. My setup is

   cifs.ko connecting to sambaA/shareA -> sambaB/shareB -> sambaB/shareC
  
using unix extensions and both servers having 'msdfs host = yes' and
shareA, shareB with 'msdfs root = yes'.

Also, how did you create your symbolic links on the samba machine?
(exact command). Just a hunch at this point but you might want to check
you properly used _two_ backslashes at the start of the link target.

Cheers,

-- 
Aurélien Aptel / SUSE Labs Samba Team
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