Re: [PATCH V5 01/13] namespaces: assign each namespace instance a serial number

[Richard Guy Briggs <rgb-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

On 14/10/06, Chen, Hanxiao wrote:
> > -----Original Message-----
> > From: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org
> > [mailto:containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org] On Behalf Of Richard Guy
> > Briggs
> > Sent: Monday, October 06, 2014 1:08 PM
> > To: linux-audit-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org; linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org;
> > containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org
> > Cc: eparis-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org; pmoore-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org; aviro-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org; sgrubb-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org;
> > ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org
> > Subject: [PATCH V5 01/13] namespaces: assign each namespace instance a serial
> > number
> > 
> > Generate and assign a serial number per namespace instance since boot.
> > 
> > Use a serial number per namespace (unique across one boot of one kernel)
> > instead of the inode number (which is claimed to have had the right to change
> > reserved and is not necessarily unique if there is more than one proc fs) to
> > uniquely identify it per kernel boot.
> > 
> > Signed-off-by: Richard Guy Briggs <rgb-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> > ---
> >  fs/mount.h                     |    1 +
> >  fs/namespace.c                 |    1 +
> >  include/linux/ipc_namespace.h  |    1 +
> >  include/linux/nsproxy.h        |   10 ++++++++++
> >  include/linux/pid_namespace.h  |    1 +
> >  include/linux/user_namespace.h |    1 +
> >  include/linux/utsname.h        |    1 +
> >  include/net/net_namespace.h    |    1 +
> >  init/version.c                 |    1 +
> >  ipc/msgutil.c                  |    1 +
> >  ipc/namespace.c                |    2 ++
> >  kernel/nsproxy.c               |   18 ++++++++++++++++++
> >  kernel/pid.c                   |    1 +
> >  kernel/pid_namespace.c         |    2 ++
> >  kernel/user.c                  |    1 +
> >  kernel/user_namespace.c        |    2 ++
> >  kernel/utsname.c               |    2 ++
> >  net/core/net_namespace.c       |    8 +++++++-
> >  18 files changed, 54 insertions(+), 1 deletions(-)
> > 
> > diff --git a/fs/mount.h b/fs/mount.h
> > index d55297f..c076f99 100644
> > --- a/fs/mount.h
> > +++ b/fs/mount.h
> > @@ -5,6 +5,7 @@
> >  struct mnt_namespace {
> >  	atomic_t		count;
> >  	unsigned int		proc_inum;
> > +	long long	serial_num;
> >  	struct mount *	root;
> >  	struct list_head	list;
> >  	struct user_namespace	*user_ns;
> > diff --git a/fs/namespace.c b/fs/namespace.c
> > index 182bc41..9af49ff 100644
> > --- a/fs/namespace.c
> > +++ b/fs/namespace.c
> > @@ -2486,6 +2486,7 @@ static struct mnt_namespace *alloc_mnt_ns(struct
> > user_namespace *user_ns)
> >  		kfree(new_ns);
> >  		return ERR_PTR(ret);
> >  	}
> > +	new_ns->serial_num = ns_serial();
> >  	new_ns->seq = atomic64_add_return(1, &mnt_ns_seq);
> >  	atomic_set(&new_ns->count, 1);
> >  	new_ns->root = NULL;
> > diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h
> > index 35e7eca..8ccfb2d 100644
> > --- a/include/linux/ipc_namespace.h
> > +++ b/include/linux/ipc_namespace.h
> > @@ -69,6 +69,7 @@ struct ipc_namespace {
> >  	struct user_namespace *user_ns;
> > 
> >  	unsigned int	proc_inum;
> > +	long long	serial_num;
> >  };
> > 
> >  extern struct ipc_namespace init_ipc_ns;
> > diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h
> > index b4ec59d..9d627b5 100644
> > --- a/include/linux/nsproxy.h
> > +++ b/include/linux/nsproxy.h
> > @@ -66,6 +66,16 @@ static inline struct nsproxy *task_nsproxy(struct task_struct
> > *tsk)
> >  	return rcu_dereference(tsk->nsproxy);
> >  }
> > 
> > +long long ns_serial(void);
> > +enum {
> > +	NS_IPC_INIT_SN	= 1,
> > +	NS_UTS_INIT_SN	= 2,
> > +	NS_USER_INIT_SN	= 3,
> > +	NS_PID_INIT_SN	= 4,
> > +	__NS_MAX_INIT_SN= 5,
> 
> You may need a space before '='.

Thanks, cleaned up.

> The rest looks good to me.
> 
> Thanks,
> 
> - Chen

- RGB

--
Richard Guy Briggs <rbriggs-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Senior Software Engineer, Kernel Security, AMER ENG Base Operating Systems, Red Hat
Remote, Ottawa, Canada
Voice: +1.647.777.2635, Internal: (81) 32635, Alt: +1.613.693.0684x3545