init security for init task

Added a LSM hook to initialize the security pointer of the init task.

Signed-off-by Mimi Zohar <[email protected]>

Signed-off-by Kylene Hall <[email protected]>

---
 include/linux/security.h |   17 +++++++++++++++++
 init/main.c              |    1 +
 security/dummy.c         |    6 ++++++
 3 files changed, 24 insertions(+)

include/linux/security.h +17 -0

@@ -516,6 +516,12 @@ struct swap_info_struct;
  * @task_free_security:
  *	@p contains the task_struct for process.
  *	Deallocate and clear the p->security field.
+ * @task_init_alloc_security:
+ *	@p contains the task_struct for init process.
+ *	Allocate and attach a security structure to the p->security field for
+ *	the init task. The security field is initialized to NULL when the task
+ *	structure is allocated.
+ *	Return 0 if operation was successful.
  * @task_setuid:
  *	Check permission before setting one or more of the user identity
  *	attributes of the current process.  The @flags parameter indicates

@@ -1220,6 +1226,7 @@ struct security_operations {
 	int (*task_create) (unsigned long clone_flags);
 	int (*task_alloc_security) (struct task_struct * p);
 	void (*task_free_security) (struct task_struct * p);
+	int (*task_init_alloc_security) (struct task_struct * p);
 	int (*task_setuid) (uid_t id0, uid_t id1, uid_t id2, int flags);
 	int (*task_post_setuid) (uid_t old_ruid /* or fsuid */ ,
 				 uid_t old_euid, uid_t old_suid, int flags);

@@ -1816,6 +1823,11 @@ static inline void security_task_free (s
 	security_ops->task_free_security (p);
 }
 
+static inline int security_task_init_alloc (struct task_struct *p)
+{
+	return security_ops->task_init_alloc_security (p);
+}
+
 static inline int security_task_setuid (uid_t id0, uid_t id1, uid_t id2,
 					int flags)
 {

@@ -2479,6 +2491,11 @@ static inline int security_task_alloc (s
 static inline void security_task_free (struct task_struct *p)
 { }
 
+static inline int security_task_init_alloc (struct task_struct *p)
+{
+	return 0;
+}
+
 static inline int security_task_setuid (uid_t id0, uid_t id1, uid_t id2,
 					int flags)
 {

security/dummy.c +6 -0

@@ -474,6 +474,11 @@ static void dummy_task_free_security (st
 	return;
 }
 
+static int dummy_task_init_alloc_security (struct task_struct *p)
+{
+	return 0;
+}
+
 static int dummy_task_setuid (uid_t id0, uid_t id1, uid_t id2, int flags)
 {
 	return 0;

@@ -982,6 +987,7 @@ void security_fixup_ops (struct security
 	set_to_dummy_if_null(ops, task_create);
 	set_to_dummy_if_null(ops, task_alloc_security);
 	set_to_dummy_if_null(ops, task_free_security);
+	set_to_dummy_if_null(ops, task_init_alloc_security);
 	set_to_dummy_if_null(ops, task_setuid);
 	set_to_dummy_if_null(ops, task_post_setuid);
 	set_to_dummy_if_null(ops, task_setgid);

Quoted 87 lines · Kylene Jo Hall

Added a LSM hook to initialize the security pointer of the init task.

Signed-off-by Mimi Zohar <[email protected]>

Signed-off-by Kylene Hall <[email protected]>

---
 include/linux/security.h |   17 +++++++++++++++++
 init/main.c              |    1 +
 security/dummy.c         |    6 ++++++
 3 files changed, 24 insertions(+)

include/linux/security.h +17 -0

@@ -516,6 +516,12 @@ struct swap_info_struct;
  * @task_free_security:
  *	@p contains the task_struct for process.
  *	Deallocate and clear the p->security field.
+ * @task_init_alloc_security:
+ *	@p contains the task_struct for init process.
+ *	Allocate and attach a security structure to the p->security field for
+ *	the init task. The security field is initialized to NULL when the task
+ *	structure is allocated.
+ *	Return 0 if operation was successful.
  * @task_setuid:
  *	Check permission before setting one or more of the user identity
  *	attributes of the current process.  The @flags parameter indicates

@@ -1220,6 +1226,7 @@ struct security_operations {
 	int (*task_create) (unsigned long clone_flags);
 	int (*task_alloc_security) (struct task_struct * p);
 	void (*task_free_security) (struct task_struct * p);
+	int (*task_init_alloc_security) (struct task_struct * p);
 	int (*task_setuid) (uid_t id0, uid_t id1, uid_t id2, int flags);
 	int (*task_post_setuid) (uid_t old_ruid /* or fsuid */ ,
 				 uid_t old_euid, uid_t old_suid, int flags);

@@ -1816,6 +1823,11 @@ static inline void security_task_free (s
 	security_ops->task_free_security (p);
 }
 
+static inline int security_task_init_alloc (struct task_struct *p)
+{
+	return security_ops->task_init_alloc_security (p);
+}
+
 static inline int security_task_setuid (uid_t id0, uid_t id1, uid_t id2,
 					int flags)
 {

@@ -2479,6 +2491,11 @@ static inline int security_task_alloc (s
 static inline void security_task_free (struct task_struct *p)
 { }
 
+static inline int security_task_init_alloc (struct task_struct *p)
+{
+	return 0;
+}
+
 static inline int security_task_setuid (uid_t id0, uid_t id1, uid_t id2,
 					int flags)
 {

security/dummy.c +6 -0

@@ -474,6 +474,11 @@ static void dummy_task_free_security (st
 	return;
 }
 
+static int dummy_task_init_alloc_security (struct task_struct *p)
+{
+	return 0;
+}
+
 static int dummy_task_setuid (uid_t id0, uid_t id1, uid_t id2, int flags)
 {
 	return 0;

@@ -982,6 +987,7 @@ void security_fixup_ops (struct security
 	set_to_dummy_if_null(ops, task_create);
 	set_to_dummy_if_null(ops, task_alloc_security);
 	set_to_dummy_if_null(ops, task_free_security);
+	set_to_dummy_if_null(ops, task_init_alloc_security);
 	set_to_dummy_if_null(ops, task_setuid);
 	set_to_dummy_if_null(ops, task_post_setuid);
 	set_to_dummy_if_null(ops, task_setgid);

init/main.c +1 -0

@@ -698,6 +698,7 @@ static int init(void * unused)
 	 * can be found.
 	 */
 	child_reaper = current;
+	security_task_init_alloc(current);
 

init/main.c static int init(void * unused) · line 704

Quoted 2 lines

init/main.c +0 -0

 	smp_prepare_cpus(max_cpus);
 

Why isn't this handled by upon your module's security initcall?