From: Michal Koutný Date: Fri, 26 Aug 2022 16:52:35 +0000 (+0200) Subject: cgroup: Honor caller's cgroup NS when resolving path X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=507128a0e32dbd80f5d277f4f1730e55ea504499;p=linux.git cgroup: Honor caller's cgroup NS when resolving path [ 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 --- diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 4b19f7fc4deb8..a92990f070d12 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;