Merge branch 'for-5.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

f09eacca · Linus Torvalds <[email protected]> · 2021-06-10 12:01:22 -07:00

Pull cgroup fix from Tejun Heo:
 "This is a high priority but low risk fix for a cgroup1 bug where
  rename(2) can change a cgroup's name to something which can break
  parsing of /proc/PID/cgroup"

* 'for-5.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup1: don't allow '\n' in renaming

Commit: f09eacca59d27efc15001795c33dbc78ca070732
Parents: 29a877d5 · b7e24eb1

Merge commit. Changes below are compared with the first parent: 29a877d5.

Changes

1 files changed · +4 −0

File	Status	Add	Del	Content
kernel/cgroup/cgroup-v1.c	modified	+4	−0	View file

kernel/cgroup/cgroup-v1.c

View file

diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index 8190b6b..1f274d7 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -820,6 +820,10 @@ static int cgroup1_rename(struct kernfs_node *kn, struct kernfs_node *new_parent
 	struct cgroup *cgrp = kn->priv;
 	int ret;
 
+	/* do not accept '\n' to prevent making /proc/<pid>/cgroup unparsable */
+	if (strchr(new_name_str, '\n'))
+		return -EINVAL;
+
 	if (kernfs_type(kn) != KERNFS_DIR)
 		return -ENOTDIR;
 	if (kn->parent != new_parent)