[linux-cifs-client] Re: [PATCH] [CIFS] Prevent OOPs when mounting with remote prefixpath

[Jeff Layton]

On Thu, 12 Feb 2009 23:18:16 -0600
Shirish Pargaonkar <shirishpargaonkar at gmail.com> wrote:

> On Tue, Feb 3, 2009 at 4:22 AM, Igor Mammedov <niallain at gmail.com> wrote:
> > Managed to single out the part of  DFS root support from a big patch
> > with a little modification.
> > It will report error and fail to mount if perfixpath is on remote server.
> > As well it will not scare people off with a error
> > 'kernel BUG at fs/cifs/cifs_dfs_ref.c:274!'.
> >
> >
> > ---------
> > Fixes OOPs with message 'kernel BUG at fs/cifs/cifs_dfs_ref.c:274!'.
> > Check if prefixpath in accessible while we are still in cifs_mount
> > and fail with reporting a error if we can't access prefixpath
> > (i.e. if prefixpath is located on another server)
> >
> >
> > Best regards,
> >
> > -------------------------
> > Igor Mammedov,
> > niallain "at" gmail.com
> >
> >
> >
> >
> >
> 
> We need to bring back NIPQUAD and NIPQUAD_FMT back in cifs_mount
> instead of %pI4 i..e.
> sprintf(pSesInfo->serverName, NIPQUAD_FMT,
>                                 NIPQUAD(srvTcp->addr.sockAddr.sin_addr.s_addr));
> If we sprintf hex address in serverName instead of dotted-decimal
> notation, the Path parameter in Tree Connect
> to IPC$ share on the server to get dfs referral fails,
> \\hex_address\IPC$ is not a valid UNC path name.
> 
> I have not tried on a IPv6 setup, but I suspect the same applies to
> IPv6 formatting.
> 

I'm afraid I don't follow this. %pI4 formats the address in
dotted-decimal format, not as a hex address. %pI6 should format it the
same way that NIP6_FMT did.

-- 
Jeff Layton <jlayton at redhat.com>