Re: Re: [PATCH v3 0/3] auth_gss: netns refcount leaks when use-gss-proxy==1

[wanghai (M)]

在 2019/8/2 3:53, J. Bruce Fields 写道:
> I lost track, what happened to these patches?
>
> --b.
>
> On Wed, Jun 12, 2019 at 08:09:27PM +0800, Wenbin Zeng wrote:
> > This patch series fixes an auth_gss bug that results in netns refcount
> > leaks when use-gss-proxy is set to 1.
> >
> > The problem was found in privileged docker containers with gssproxy service
> > enabled and /proc/net/rpc/use-gss-proxy set to 1, the corresponding
> > struct net->count ends up at 2 after container gets killed, the consequence
> > is that the struct net cannot be freed.
> >
> > It turns out that write_gssp() called gssp_rpc_create() to create a rpc
> > client, this increases net->count by 2; rpcsec_gss_exit_net() is supposed
> > to decrease net->count but it never gets called because its call-path is:
> >          net->count==0 -> cleanup_net -> ops_exit_list -> rpcsec_gss_exit_net
> > Before rpcsec_gss_exit_net() gets called, net->count cannot reach 0, this
> > is a deadlock situation.
> >
> > To fix the problem, we must break the deadlock, rpcsec_gss_exit_net()
> > should move out of the put() path and find another chance to get called,
> > I think nsfs_evict() is a good place to go, when netns inode gets evicted
> > we call rpcsec_gss_exit_net() to free the rpc client, this requires a new
> > callback i.e. evict to be added in struct proc_ns_operations, and add
> > netns_evict() as one of netns_operations as well.
> >
> > v1->v2:
> >   * in nsfs_evict(), move ->evict() in front of ->put()
> > v2->v3:
> >   * rpcsec_gss_evict_net() directly call gss_svc_shutdown_net() regardless
> >     if gssp_clnt is null, this is exactly same to what rpcsec_gss_exit_net()
> >     previously did
> >
> > Wenbin Zeng (3):
> >    nsfs: add evict callback into struct proc_ns_operations
> >    netns: add netns_evict into netns_operations
> >    auth_gss: fix deadlock that blocks rpcsec_gss_exit_net when
> >      use-gss-proxy==1
> >
> >   fs/nsfs.c                      |  2 ++
> >   include/linux/proc_ns.h        |  1 +
> >   include/net/net_namespace.h    |  1 +
> >   net/core/net_namespace.c       | 12 ++++++++++++
> >   net/sunrpc/auth_gss/auth_gss.c |  4 ++--
> >   5 files changed, 18 insertions(+), 2 deletions(-)
> >
> > --
> > 1.8.3.1
These patchsets don't seem to merge into the mainline, are there any 
other patches that fix this bug?