1 files changed, 46 insertions, 0 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 91b06f2aa963..520f82ab3fbf 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3277,6 +3277,50 @@ static void selinux_cred_commit(struct cred *new, const struct cred *old)
         secondary_ops->cred_commit(new, old);
 }
 
+/*
+ * set the security data for a kernel service
+ * - all the creation contexts are set to unlabelled
+ */
+static int selinux_kernel_act_as(struct cred *new, u32 secid)
+{
+        struct task_security_struct *tsec = new->security;
+        u32 sid = current_sid();
+        int ret;
+
+        ret = avc_has_perm(sid, secid,
+                           SECCLASS_KERNEL_SERVICE,
+                           KERNEL_SERVICE__USE_AS_OVERRIDE,
+                           NULL);
+        if (ret == 0) {
+                tsec->sid = secid;
+                tsec->create_sid = 0;
+                tsec->keycreate_sid = 0;
+                tsec->sockcreate_sid = 0;
+        }
+        return ret;
+}
+
+/*
+ * set the file creation context in a security record to the same as the
+ * objective context of the specified inode
+ */
+static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
+{
+        struct inode_security_struct *isec = inode->i_security;
+        struct task_security_struct *tsec = new->security;
+        u32 sid = current_sid();
+        int ret;
+
+        ret = avc_has_perm(sid, isec->sid,
+                           SECCLASS_KERNEL_SERVICE,
+                           KERNEL_SERVICE__CREATE_FILES_AS,
+                           NULL);
+
+        if (ret == 0)
+                tsec->create_sid = isec->sid;
+        return 0;
+}
+
 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
 {
         /* Since setuid only affects the current process, and
@@ -5593,6 +5637,8 @@ static struct security_operations selinux_ops = {
         .cred_free =                    selinux_cred_free,
         .cred_prepare =                 selinux_cred_prepare,
         .cred_commit =                  selinux_cred_commit,
+        .kernel_act_as =                selinux_kernel_act_as,
+        .kernel_create_files_as =       selinux_kernel_create_files_as,
         .task_setuid =                  selinux_task_setuid,
         .task_fix_setuid =              selinux_task_fix_setuid,
         .task_setgid =                  selinux_task_setgid,