From 507128a0e32dbd80f5d277f4f1730e55ea504499 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Michal=20Koutn=C3=BD?= Date: Fri, 26 Aug 2022 18:52:35 +0200 Subject: [PATCH] cgroup: Honor caller's cgroup NS when resolving path MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 74e4b956eb1cac0e4c10c240339b1bbfbc9a4c48 ] cgroup_get_from_path() is not widely used function. Its callers presume the path is resolved under cgroup namespace. (There is one caller currently and resolving in init NS won't make harm (netfilter). However, future users may be subject to different effects when resolving globally.) Since, there's currently no use for the global resolution, modify the existing function to take cgroup NS into account. Fixes: a79a908fd2b0 ("cgroup: introduce cgroup namespaces") Signed-off-by: Michal Koutný Signed-off-by: Tejun Heo Signed-off-by: Sasha Levin --- kernel/cgroup/cgroup.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 4b19f7fc4deb..a92990f070d1 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -6598,8 +6598,12 @@ struct cgroup *cgroup_get_from_path(const char *path) { struct kernfs_node *kn; struct cgroup *cgrp = ERR_PTR(-ENOENT); + struct cgroup *root_cgrp; - kn = kernfs_walk_and_get(cgrp_dfl_root.cgrp.kn, path); + spin_lock_irq(&css_set_lock); + root_cgrp = current_cgns_cgroup_from_root(&cgrp_dfl_root); + kn = kernfs_walk_and_get(root_cgrp->kn, path); + spin_unlock_irq(&css_set_lock); if (!kn) goto out;