OpenVZ Forum


Home » Mailing lists » Devel » [RFC PATCH 0/5] net: socket bind to file descriptor introduced
Re: [RFC PATCH 0/5] net: socket bind to file descriptor introduced [message #47560 is a reply to message #47535] Thu, 16 August 2012 03:03 Go to previous messageGo to previous message
ebiederm is currently offline  ebiederm
Messages: 1354
Registered: February 2006
Senior Member
Stanislav Kinsbursky <skinsbursky@parallels.com> writes:

> This patch set introduces new socket operation and new system call:
> sys_fbind(), which allows to bind socket to opened file.
> File to bind to can be created by sys_mknod(S_IFSOCK) and opened by
> open(O_PATH).
>
> This system call is especially required for UNIX sockets, which has name
> lenght limitation.
>
> The following series implements...

Hmm. I just realized this patchset is even sillier than I thought.

Stanislav is the problem you are ultimately trying to solve nfs clients
in a container connecting to the wrong user space rpciod?

Aka net/sunrpc/xprtsock.c:xs_setup_local only taking an absolute path
and then creating a delayed work item to actually open the unix domain
socket?

The straight correct and straight forward thing to do appears to be:
- Capture the root from current->fs in xs_setup_local.
- In xs_local_finish_connect change current->fs.root to the captured
version of root before kernel_connect, and restore current->fs.root
after kernel_connect.

It might not be a bad idea to implement open on unix domain sockets in
a filesystem as create(AF_LOCAL)+connect() which would allow you to
replace __sock_create + kernel_connect with a simple file_open_root.

But I think the simple scheme of:
struct path old_root;
old_root = current->fs.root;
kernel_connect(...);
current->fs.root = old_root;

Is more than sufficient and will remove the need for anything
except a purely local change to get nfs clients to connect from
containers.

Eric
 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: [PATCH v3 04/13] kmem accounting basic infrastructure
Next Topic: [PATCH v3 00/13] kmem controller for memcg.
Goto Forum:
  


Current Time: Sun Jul 20 10:03:56 GMT 2025

Total time taken to generate the page: 0.07381 seconds