[linux-cifs-client] CIFS and rename of open files

[Jeff Layton]

On Fri, 25 Jul 2008 19:39:14 +0200
Wilhelm Meier <wilhelm.meier at fh-kl.de> wrote:

> Hello again,
> 
> here comes a minimal test program what does essentially the same as 
> kmail does:
> 
> open to files
> leave them open
> rename the first as the second -> permission denied on cifs
> 
> This works as expected on local fs like ext2/3, but not on a 
> cifs-share.
> 
> This is the version information:
> 
> Display Internal CIFS Data Structures for Debugging
> ---------------------------------------------------
> CIFS Version 1.52
> Active VFS Requests: 0
> Servers:
> 1) Name: 192.168.32.12  Domain: KMUX Mounts: 1 OS: Unix
>         NOS: Samba 3.0.24       Capability: 0x80f3fd
>         SMB session status: 1   TCP status: 1
>         Local Users To Server: 1 SecMode: 0x3 Req On Wire: 0
> MIDs:
> 
> Shares:
> 1) \\192.168.32.12\hugo.tester Uses: 1 Type: NTFS DevInfo: 0x0 
> Attributes: 0x2b
> PathComponentMax: 255 Status: 1 type: 0
> 
> I would be _very_ happy, I you can give me a solution to this 
> problem!!!
> 
> TIA,
> 
> Wilhelm
> 
> Am Montag, 30. Juni 2008 schrieb Jeff Layton:
> > On Wed, 25 Jun 2008 09:52:23 +0200
> >
> > Wilhelm Meier <wilhelm.meier at fh-kl.de> wrote:
> > > Hello Jeff,
> > >
> > > Am Freitag, 6. Juni 2008 schrieb Wilhelm Meier:
> > > > Am Freitag, 6. Juni 2008 schrieb Jeff Layton:
> > > > > On Fri, 6 Jun 2008 10:49:26 +0200
> > > > >
> > > > > Wilhelm Meier <wilhelm.meier at fh-kl.de> wrote:
> > > > > > Hello,
> > > > > >
> > > > > > are there any news to the issue of renaming open files -
> > > > > > because this missing feature is preventing the use of cifs
> > > > > > as user homes on linux systems.
> > > > >
> > > > > I was looking at the problem earlier this week, but haven't
> > > > > gotten all the way to a solution. The issue is very dependent
> > > > > on server behavior, with windows servers being particularly
> > > > > problematic. I've been doing some experimentation, but
> > > > > haven't found a solution that seems to work well for all
> > > > > cases.
> > >
> > > is there any progess or activity from your side? I'm asking
> > > because this is a show-stopper using cifs-homes for users with
> > > newer kmail-versions.
> > > Or do you know any workaround in this respect?
> >
> > I'm afraid that I've been sidetracked into other things and haven't
> > had time to touch this. The problem is (I think) that CIFS
> > currently tries to set the DELETE_ON_CLOSE bit using the create
> > flags in the open call, but this only works if the file is actually
> > being created. So we need to set the bit with a SET_FILE_INFO call
> > and then try to rename it.
> >
> > I'm probably wrong on some of this though, this turns out to be a
> > rather tricky situation to handle correctly, and it will probably
> > take some experimentation to get it right. I don't know of any
> > workarounds for this at the moment...
> >
> > > > Sorry for being unclear here: I mean linux-cifs in combination
> > > > with samba-server
> 
> 
> 

I may try to give a crack at this soon. It looks like someone else
reported this problem in this samba BZ ticket:

https://bugzilla.samba.org/show_bug.cgi?id=5534

I went ahead and attached your test program to it and assigned the case
to myself. You may want to cc yourself on this bug as I'll probably try
to put updates in there as I work on it.

-- 
Jeff Layton <jlayton at redhat.com>