linux-kernel - Re: [PATCH v2 19/33] cgroup: support ns lookup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <wx455y2gvdfkpg34r5apf3kzgj4yu6x2s45vgvrjitlgyayrum@lhrpijrvkmpm>
Date: Mon, 15 Sep 2025 13:53:05 +0200
From: Jan Kara <jack@...e.cz>
To: Christian Brauner <brauner@...nel.org>
Cc: Jan Kara <jack@...e.cz>, Amir Goldstein <amir73il@...il.com>, 
	linux-fsdevel@...r.kernel.org, Josef Bacik <josef@...icpanda.com>, 
	Jeff Layton <jlayton@...nel.org>, Mike Yuan <me@...dnzj.com>, 
	Zbigniew Jędrzejewski-Szmek <zbyszek@...waw.pl>, Lennart Poettering <mzxreary@...inter.de>, 
	Daan De Meyer <daan.j.demeyer@...il.com>, Aleksa Sarai <cyphar@...har.com>, 
	Alexander Viro <viro@...iv.linux.org.uk>, Jens Axboe <axboe@...nel.dk>, Tejun Heo <tj@...nel.org>, 
	Johannes Weiner <hannes@...xchg.org>, Michal Koutný <mkoutny@...e.com>, 
	Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, 
	Paolo Abeni <pabeni@...hat.com>, Simon Horman <horms@...nel.org>, 
	Chuck Lever <chuck.lever@...cle.com>, linux-nfs@...r.kernel.org, linux-kselftest@...r.kernel.org, 
	linux-block@...r.kernel.org, linux-kernel@...r.kernel.org, cgroups@...r.kernel.org, 
	netdev@...r.kernel.org
Subject: Re: [PATCH v2 19/33] cgroup: support ns lookup

On Fri 12-09-25 13:52:42, Christian Brauner wrote:
> Support the generic ns lookup infrastructure to support file handles for
> namespaces.
> 
> Acked-by: Tejun Heo <tj@...nel.org>
> Signed-off-by: Christian Brauner <brauner@...nel.org>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@...e.cz>

								Honza

> ---
>  kernel/cgroup/cgroup.c    | 2 ++
>  kernel/cgroup/namespace.c | 7 +++++--
>  2 files changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
> index 312c6a8b55bb..092e6bf081ed 100644
> --- a/kernel/cgroup/cgroup.c
> +++ b/kernel/cgroup/cgroup.c
> @@ -59,6 +59,7 @@
>  #include <linux/sched/cputime.h>
>  #include <linux/sched/deadline.h>
>  #include <linux/psi.h>
> +#include <linux/nstree.h>
>  #include <net/sock.h>
>  
>  #define CREATE_TRACE_POINTS
> @@ -6312,6 +6313,7 @@ int __init cgroup_init(void)
>  	WARN_ON(register_filesystem(&cpuset_fs_type));
>  #endif
>  
> +	ns_tree_add(&init_cgroup_ns);
>  	return 0;
>  }
>  
> diff --git a/kernel/cgroup/namespace.c b/kernel/cgroup/namespace.c
> index 0391b6ab0bf1..fc12c416dfeb 100644
> --- a/kernel/cgroup/namespace.c
> +++ b/kernel/cgroup/namespace.c
> @@ -5,7 +5,7 @@
>  #include <linux/slab.h>
>  #include <linux/nsproxy.h>
>  #include <linux/proc_ns.h>
> -
> +#include <linux/nstree.h>
>  
>  /* cgroup namespaces */
>  
> @@ -30,16 +30,19 @@ static struct cgroup_namespace *alloc_cgroup_ns(void)
>  	ret = ns_common_init(&new_ns->ns, &cgroupns_operations, true);
>  	if (ret)
>  		return ERR_PTR(ret);
> +	ns_tree_add(new_ns);
>  	return no_free_ptr(new_ns);
>  }
>  
>  void free_cgroup_ns(struct cgroup_namespace *ns)
>  {
> +	ns_tree_remove(ns);
>  	put_css_set(ns->root_cset);
>  	dec_cgroup_namespaces(ns->ucounts);
>  	put_user_ns(ns->user_ns);
>  	ns_free_inum(&ns->ns);
> -	kfree(ns);
> +	/* Concurrent nstree traversal depends on a grace period. */
> +	kfree_rcu(ns, ns.ns_rcu);
>  }
>  EXPORT_SYMBOL(free_cgroup_ns);
>  
> 
> -- 
> 2.47.3
> 
-- 
Jan Kara <jack@...e.com>
SUSE Labs, CR