tree 7385f35edda9f4124b802ccf337c55070d2e00bc
parent b7c6ba6eb1234e35a74fb8ba8123232a7b1ba9e4
author Denis V. Lunev <den@openvz.org> 1200729319 -0800
committer David S. Miller <davem@davemloft.net> 1201561688 -0800

[NETNS]: Namespace stop vs 'ip r l' race.

During network namespace stop process kernel side netlink sockets
belonging to a namespace should be closed. They should not prevent
namespace to stop, so they do not increment namespace usage
counter. Though this counter will be put during last sock_put.

The raplacement of the correct netns for init_ns solves the problem
only partial as socket to be stoped until proper stop is a valid
netlink kernel socket and can be looked up by the user processes. This
is not a problem until it resides in initial namespace (no processes
inside this net), but this is not true for init_net.

So, hold the referrence for a socket, remove it from lookup tables and
only after that change namespace and perform a last put.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Tested-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>