From: Eric W. Biederman <ebiederm@xmission.com>
Date: Mon, 12 Mar 2012 22:44:39 +0000 (-0700)
Subject: userns: Convert cgroup permission checks to use uid_eq
X-Git-Url: http://git.mmlx.us/?a=commitdiff_plain;h=14a590c3f987977d7b09ec926481ee0238c08eee;p=linux-edison.git

userns: Convert cgroup permission checks to use uid_eq

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---

diff --git a/init/Kconfig b/init/Kconfig
index 7a5ccb2e9e0..d24cc75caf6 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -865,7 +865,6 @@ config UIDGID_CONVERTED
 
 	# List of kernel pieces that need user namespace work
 	# Features
-	depends on CGROUPS = n
 	depends on MIGRATION = n
 	depends on NUMA = n
 	depends on SYSVIPC = n
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index ed64ccac67c..c8329b0c257 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2160,9 +2160,9 @@ retry_find_task:
 		 * only need to check permissions on one of them.
 		 */
 		tcred = __task_cred(tsk);
-		if (cred->euid &&
-		    cred->euid != tcred->uid &&
-		    cred->euid != tcred->suid) {
+		if (!uid_eq(cred->euid, GLOBAL_ROOT_UID) &&
+		    !uid_eq(cred->euid, tcred->uid) &&
+		    !uid_eq(cred->euid, tcred->suid)) {
 			rcu_read_unlock();
 			ret = -EACCES;
 			goto out_unlock_cgroup;