From e5fd91f1ef340da553f7a79da9540c3db711c937 Mon Sep 17 00:00:00 2001
From: André Fabian Silva Delgado <emulatorman@parabola.nu>
Date: Tue, 8 Sep 2015 01:01:14 -0300
Subject: Linux-libre 4.2-gnu

---
 security/yama/yama_lsm.c | 61 +++++++++++++++++-------------------------------
 1 file changed, 21 insertions(+), 40 deletions(-)

(limited to 'security/yama')

diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index 24aae2ae2..5ebb89687 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -12,7 +12,7 @@
  *
  */
 
-#include <linux/security.h>
+#include <linux/lsm_hooks.h>
 #include <linux/sysctl.h>
 #include <linux/ptrace.h>
 #include <linux/prctl.h>
@@ -154,13 +154,9 @@ void yama_task_free(struct task_struct *task)
 int yama_task_prctl(int option, unsigned long arg2, unsigned long arg3,
 			   unsigned long arg4, unsigned long arg5)
 {
-	int rc;
+	int rc = -ENOSYS;
 	struct task_struct *myself = current;
 
-	rc = cap_task_prctl(option, arg2, arg3, arg4, arg5);
-	if (rc != -ENOSYS)
-		return rc;
-
 	switch (option) {
 	case PR_SET_PTRACER:
 		/* Since a thread can call prctl(), find the group leader
@@ -279,17 +275,10 @@ static int ptracer_exception_found(struct task_struct *tracer,
  *
  * Returns 0 if following the ptrace is allowed, -ve on error.
  */
-int yama_ptrace_access_check(struct task_struct *child,
+static int yama_ptrace_access_check(struct task_struct *child,
 				    unsigned int mode)
 {
-	int rc;
-
-	/* If standard caps disallows it, so does Yama.  We should
-	 * only tighten restrictions further.
-	 */
-	rc = cap_ptrace_access_check(child, mode);
-	if (rc)
-		return rc;
+	int rc = 0;
 
 	/* require ptrace target be a child of ptracer on attach */
 	if (mode == PTRACE_MODE_ATTACH) {
@@ -335,14 +324,7 @@ int yama_ptrace_access_check(struct task_struct *child,
  */
 int yama_ptrace_traceme(struct task_struct *parent)
 {
-	int rc;
-
-	/* If standard caps disallows it, so does Yama.  We should
-	 * only tighten restrictions further.
-	 */
-	rc = cap_ptrace_traceme(parent);
-	if (rc)
-		return rc;
+	int rc = 0;
 
 	/* Only disallow PTRACE_TRACEME on more aggressive settings. */
 	switch (ptrace_scope) {
@@ -364,16 +346,17 @@ int yama_ptrace_traceme(struct task_struct *parent)
 	return rc;
 }
 
-#ifndef CONFIG_SECURITY_YAMA_STACKED
-static struct security_operations yama_ops = {
-	.name =			"yama",
-
-	.ptrace_access_check =	yama_ptrace_access_check,
-	.ptrace_traceme =	yama_ptrace_traceme,
-	.task_prctl =		yama_task_prctl,
-	.task_free =		yama_task_free,
+static struct security_hook_list yama_hooks[] = {
+	LSM_HOOK_INIT(ptrace_access_check, yama_ptrace_access_check),
+	LSM_HOOK_INIT(ptrace_traceme, yama_ptrace_traceme),
+	LSM_HOOK_INIT(task_prctl, yama_task_prctl),
+	LSM_HOOK_INIT(task_free, yama_task_free),
 };
-#endif
+
+void __init yama_add_hooks(void)
+{
+	security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks));
+}
 
 #ifdef CONFIG_SYSCTL
 static int yama_dointvec_minmax(struct ctl_table *table, int write,
@@ -418,16 +401,14 @@ static struct ctl_table yama_sysctl_table[] = {
 static __init int yama_init(void)
 {
 #ifndef CONFIG_SECURITY_YAMA_STACKED
-	if (!security_module_enable(&yama_ops))
+	/*
+	 * If yama is being stacked this is already taken care of.
+	 */
+	if (!security_module_enable("yama"))
 		return 0;
+	yama_add_hooks();
 #endif
-
-	printk(KERN_INFO "Yama: becoming mindful.\n");
-
-#ifndef CONFIG_SECURITY_YAMA_STACKED
-	if (register_security(&yama_ops))
-		panic("Yama: kernel registration failed.\n");
-#endif
+	pr_info("Yama: becoming mindful.\n");
 
 #ifdef CONFIG_SYSCTL
 	if (!register_sysctl_paths(yama_sysctl_path, yama_sysctl_table))
-- 
cgit v1.2.3-54-g00ecf