linux-kernel - [PATCH v2] cgroup: reject cgroup names with '\n'

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1408360820-3390-1-git-send-email-alban.crequy@collabora.co.uk>
Date:	Mon, 18 Aug 2014 12:20:20 +0100
From:	Alban Crequy <alban.crequy@...labora.co.uk>
To:	Alban Crequy <alban.crequy@...labora.co.uk>,
	Tejun Heo <tj@...nel.org>, cgroups@...r.kernel.org,
	linux-kernel@...r.kernel.org, Li Zefan <lizefan@...wei.com>
Subject: [PATCH v2] cgroup: reject cgroup names with '\n'

/proc/<pid>/cgroup contains one cgroup path on each line. If cgroup names are
allowed to contain "\n", applications cannot parse /proc/<pid>/cgroup safely.

Signed-off-by: Alban Crequy <alban.crequy@...labora.co.uk>
---
v2: Fixed according to comments from Tejun Heo: only reject '\n'

 kernel/cgroup.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 7dc8788..c3d1802 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4543,6 +4543,11 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
 	struct cftype *base_files;
 	int ssid, ret;
 
+	/* Do not accept '\n' to prevent making /proc/<pid>/cgroup unparsable.
+	 */
+	if (strchr(name, '\n'))
+		return -EINVAL;
+
 	parent = cgroup_kn_lock_live(parent_kn);
 	if (!parent)
 		return -ENODEV;
-- 
1.8.5.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/