Messages in this thread | | | From | (Eric W. Biederman) | Date | Tue, 09 Sep 2008 11:20:18 -0700 | Subject | Re: [RFC][PATCH] sunrpc: fix oops in rpc_create() when the mount namespace is unshared |
| |
Chuck Lever <chuck.lever@oracle.com> writes:
> If the upper layers are responsible for providing the utsname, you will need to > fix up lockd and the NFS server's callback client too, at least.
Actually looking at the code. It looks like a proper fix may be even simpler. Why do we have both clnt->cl_server and clnt->cl_nodename? Or is cl_server the other side of the connection?
>>> What are we trying to achieve by reading utsname? >> >> It looks like it gets copied into the sunrpc messages so I assume it is >> a part of the sunrpc spec? > > It appears to be used only for RPC's AUTH_SYS credentials. The nodename is used > to identify the caller's host. See RFC 1831, Appendix A: > > http://rfclibrary.hosting.com/rfc/rfc1831/rfc1831-16.asp
Thanks that helps a lot.
> I'm not terribly familiar with uts namespaces, though. Can someone explain why > we need to distinguish between these for AUTH_SYS if the caller is on a remote > system?
Semantically processes in different uts namespaces are on different machines.
> I don't like the idea of an oops in here. Instead, (for now) it should warn and > fail to create the client, IMO.
Which is interesting when the problem happens during NFS unmount. Although frankly it could fail anyway.
It seems strange that we are creating a client during unmount anyway.
Eric
| |