Commit 5204214f authored by Zefan Li's avatar Zefan Li Committed by yanhaitao
Browse files

cgroup: check if cgroup root is alive in cgroupstats_show() 

euler inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8QLND


CVE: N/A

-------------------------------------------------

If a cgroup root is dying, show its hierarchy_id and num_cgroups
as 0.

Signed-off-by: default avatarZefan Li <lizefan@huawei.com>
Signed-off-by: default avatarchenridong <chenridong@huawei.com>
parent 6d225089

kernel/cgroup/cgroup-v1.c

+6 −3
Original line number Diff line number Diff line
@@ -675,6 +675,7 @@ int proc_cgroupstats_show(struct seq_file *m, void *v) 
{

	struct cgroup_subsys *ss;

	int i;

	bool dead;



	seq_puts(m, "#subsys_name\thierarchy\tnum_cgroups\tenabled\n");

	/*
@@ -682,11 +683,13 @@ int proc_cgroupstats_show(struct seq_file *m, void *v) 
	 * cgroup_mutex contention.

	 */



	for_each_subsys(ss, i)

	for_each_subsys(ss, i) {

		dead = percpu_ref_is_dying(&ss->root->cgrp.self.refcnt);

		seq_printf(m, "%s\t%d\t%d\t%d\n",

			   ss->legacy_name, ss->root->hierarchy_id,

			   atomic_read(&ss->root->nr_cgrps),

			   ss->legacy_name, dead ? 0 : ss->root->hierarchy_id,

			   dead ? 0 : atomic_read(&ss->root->nr_cgrps),

			   cgroup_ssid_enabled(i));

	}



	return 0;

}