Merge branch 'linux-linaro-lsk' into linux-linaro-lsk-android

[firefly-linux-kernel-4.4.55.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index 987b28a1f01b6c6ce5d554eb22d9c89e1cde1e7b..41671a5d637d0b6cd7c4ccdd0ec81f8708a33708 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -198,6 +198,9 @@ struct kmem_cache *vm_area_cachep;
 /* SLAB cache for mm_struct structures (tsk->mm) */
 static struct kmem_cache *mm_cachep;
 
+/* Notifier list called when a task struct is freed */
+static ATOMIC_NOTIFIER_HEAD(task_free_notifier);
+
 static void account_kernel_stack(struct thread_info *ti, int account)
 {
        struct zone *zone = page_zone(virt_to_page(ti));
@@ -231,6 +234,18 @@ static inline void put_signal_struct(struct signal_struct *sig)
                free_signal_struct(sig);
 }
 
+int task_free_register(struct notifier_block *n)
+{
+       return atomic_notifier_chain_register(&task_free_notifier, n);
+}
+EXPORT_SYMBOL(task_free_register);
+
+int task_free_unregister(struct notifier_block *n)
+{
+       return atomic_notifier_chain_unregister(&task_free_notifier, n);
+}
+EXPORT_SYMBOL(task_free_unregister);
+
 void __put_task_struct(struct task_struct *tsk)
 {
        WARN_ON(!tsk->exit_state);
@@ -242,6 +257,7 @@ void __put_task_struct(struct task_struct *tsk)
        delayacct_tsk_free(tsk);
        put_signal_struct(tsk->signal);
 
+       atomic_notifier_call_chain(&task_free_notifier, 0, tsk);
        if (!profile_handoff_task(tsk))
                free_task(tsk);
 }
@@ -696,7 +712,8 @@ struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
 
        mm = get_task_mm(task);
        if (mm && mm != current->mm &&
-                       !ptrace_may_access(task, mode)) {
+                       !ptrace_may_access(task, mode) &&
+                       !capable(CAP_SYS_RESOURCE)) {
                mmput(mm);
                mm = ERR_PTR(-EACCES);
        }