linux-stable/kernel/cgroup
Alexander Kuznetsov 7e7ff4d058 cgroup1: don't allow '\n' in renaming
commit b7e24eb1ca upstream.

cgroup_mkdir() have restriction on newline usage in names:
$ mkdir $'/sys/fs/cgroup/cpu/test\ntest2'
mkdir: cannot create directory
'/sys/fs/cgroup/cpu/test\ntest2': Invalid argument

But in cgroup1_rename() such check is missed.
This allows us to make /proc/<pid>/cgroup unparsable:
$ mkdir /sys/fs/cgroup/cpu/test
$ mv /sys/fs/cgroup/cpu/test $'/sys/fs/cgroup/cpu/test\ntest2'
$ echo $$ > $'/sys/fs/cgroup/cpu/test\ntest2'
$ cat /proc/self/cgroup
11:pids:/
10:freezer:/
9:hugetlb:/
8:cpuset:/
7:blkio:/user.slice
6:memory:/user.slice
5:net_cls,net_prio:/
4:perf_event:/
3:devices:/user.slice
2:cpu,cpuacct:/test
test2
1:name=systemd:/
0::/

Signed-off-by: Alexander Kuznetsov <wwfq@yandex-team.ru>
Reported-by: Andrey Krasichkov <buglloc@yandex-team.ru>
Acked-by: Dmitry Yakunin <zeil@yandex-team.ru>
Cc: stable@vger.kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-16 11:54:59 +02:00
..
cgroup-internal.h cgroup/tracing: Move taking of spin lock out of trace event handlers 2018-07-11 10:48:47 -07:00
cgroup-v1.c cgroup1: don't allow '\n' in renaming 2021-06-16 11:54:59 +02:00
cgroup.c cgroup: disable controllers at parse time 2021-06-16 11:54:57 +02:00
cpuset.c cpuset: restore sanity to cpuset_cpus_allowed_fallback() 2019-07-10 09:53:39 +02:00
debug.c debug cgroup: use task_css_set instead of rcu_dereference 2017-11-27 11:37:33 -08:00
freezer.c cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS 2017-07-21 11:14:51 -04:00
Makefile cgroup: Rename kernel/cgroup/stat.c to kernel/cgroup/rstat.c 2018-04-26 14:29:04 -07:00
namespace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pids.c cgroup: pids: use atomic64_t for pids->limit 2019-12-17 20:34:56 +01:00
rdma.c rdmacg: Convert to use match_string() helper 2018-05-07 09:27:26 -07:00
rstat.c Revert "cgroup: Add memory barriers to plug cgroup_rstat_updated() race window" 2020-06-07 13:17:53 +02:00