C++ (Cpp) clear_user_return_notifier示例

示例#1

文件： fork.c 项目： HONO/Bell_V20f_kernel_mod

static struct task_struct *dup_task_struct(struct task_struct *orig)
{
	struct task_struct *tsk;
	struct thread_info *ti;
	unsigned long *stackend;
	int node = tsk_fork_get_node(orig);
	int err;

	prepare_to_copy(orig);

	tsk = alloc_task_struct_node(node);
	if (!tsk)
		return NULL;

	ti = alloc_thread_info_node(tsk, node);
	if (!ti) {
		free_task_struct(tsk);
		return NULL;
	}

 	err = arch_dup_task_struct(tsk, orig);
	if (err)
		goto out;

	tsk->stack = ti;

	err = prop_local_init_single(&tsk->dirties);
	if (err)
		goto out;

	setup_thread_stack(tsk, orig);
	clear_user_return_notifier(tsk);
	clear_tsk_need_resched(tsk);
	stackend = end_of_stack(tsk);
	*stackend = STACK_END_MAGIC;	/* for overflow detection */

#ifdef CONFIG_CC_STACKPROTECTOR
	tsk->stack_canary = get_random_int();
#endif

	/* One for us, one for whoever does the "release_task()" (usually parent) */
	atomic_set(&tsk->usage,2);
	atomic_set(&tsk->fs_excl, 0);
#ifdef CONFIG_BLK_DEV_IO_TRACE
	tsk->btrace_seq = 0;
#endif
	tsk->splice_pipe = NULL;

	account_kernel_stack(ti, 1);

	return tsk;

out:
	free_thread_info(ti);
	free_task_struct(tsk);
	return NULL;
}

示例#2

文件： fork.c 项目： AlahmadiQ8/EEM202B_ProjectSubmission

static struct task_struct *dup_task_struct(struct task_struct *orig)
{
	struct task_struct *tsk;
	struct thread_info *ti;
	unsigned long *stackend;
	int node = tsk_fork_get_node(orig);
	int err;

	tsk = alloc_task_struct_node(node);
	if (!tsk)
		return NULL;

	ti = alloc_thread_info_node(tsk, node);
	if (!ti)
		goto free_tsk;

	err = arch_dup_task_struct(tsk, orig);
	if (err)
		goto free_ti;

	tsk->stack = ti;

	setup_thread_stack(tsk, orig);
	clear_user_return_notifier(tsk);
	clear_tsk_need_resched(tsk);
	stackend = end_of_stack(tsk);
	*stackend = STACK_END_MAGIC;	/* for overflow detection */

#ifdef CONFIG_CC_STACKPROTECTOR
	tsk->stack_canary = get_random_int();
#endif

	/*
	 * One for us, one for whoever does the "release_task()" (usually
	 * parent)
	 */
	atomic_set(&tsk->usage, 2);
#ifdef CONFIG_BLK_DEV_IO_TRACE
	tsk->btrace_seq = 0;
#endif
	tsk->splice_pipe = NULL;

	account_kernel_stack(ti, 1);

	memset(&(tsk->vemu), 0, sizeof(vemu_state));

	return tsk;

free_ti:
	free_thread_info(ti);
free_tsk:
	free_task_struct(tsk);
	return NULL;
}

示例#3

文件： fork.c 项目： MiniBlu/cm11_kernel_htc_msm8974a3ul

static struct task_struct *dup_task_struct(struct task_struct *orig)
{
	struct task_struct *tsk;
	struct thread_info *ti;
	unsigned long *stackend;
	int node = tsk_fork_get_node(orig);
	int err;

	prepare_to_copy(orig);

	tsk = alloc_task_struct_node(node);
	if (!tsk)
		return NULL;

	ti = alloc_thread_info_node(tsk, node);
	if (!ti) {
		free_task_struct(tsk);
		return NULL;
	}

	err = arch_dup_task_struct(tsk, orig);
	if (err)
		goto out;

	tsk->stack = ti;

	setup_thread_stack(tsk, orig);
	clear_user_return_notifier(tsk);
	clear_tsk_need_resched(tsk);
	stackend = end_of_stack(tsk);
	*stackend = STACK_END_MAGIC;	

#ifdef CONFIG_CC_STACKPROTECTOR
	tsk->stack_canary = get_random_int();
#endif

	atomic_set(&tsk->usage, 2);
#ifdef CONFIG_BLK_DEV_IO_TRACE
	tsk->btrace_seq = 0;
#endif
	tsk->splice_pipe = NULL;

	account_kernel_stack(ti, 1);

	return tsk;

out:
	free_thread_info(ti);
	free_task_struct(tsk);
	return NULL;
}

示例#4

文件： fork.c 项目： cm13-rhine/android_kernel_sony_msm8974

static struct task_struct *dup_task_struct(struct task_struct *orig)
{
	struct task_struct *tsk;
	struct thread_info *ti;
	unsigned long *stackend;
	int node = tsk_fork_get_node(orig);
	int err;

	prepare_to_copy(orig);

	tsk = alloc_task_struct_node(node);
	if (!tsk)
		return NULL;

	ti = alloc_thread_info_node(tsk, node);
	if (!ti) {
		free_task_struct(tsk);
		return NULL;
	}

	err = arch_dup_task_struct(tsk, orig);
	if (err)
		goto out;

	tsk->stack = ti;
#ifdef CONFIG_SECCOMP
	/*
	 * We must handle setting up seccomp filters once we're under
	 * the sighand lock in case orig has changed between now and
	 * then. Until then, filter must be NULL to avoid messing up
	 * the usage counts on the error path calling free_task.
	 */
	tsk->seccomp.filter = NULL;
#endif

	setup_thread_stack(tsk, orig);
	clear_user_return_notifier(tsk);
	clear_tsk_need_resched(tsk);
	stackend = end_of_stack(tsk);
	*stackend = STACK_END_MAGIC;	/* for overflow detection */

#ifdef CONFIG_CC_STACKPROTECTOR
	tsk->stack_canary = get_random_int();
#endif

	/*
	 * One for us, one for whoever does the "release_task()" (usually
	 * parent)
	 */
	atomic_set(&tsk->usage, 2);
#ifdef CONFIG_BLK_DEV_IO_TRACE
	tsk->btrace_seq = 0;
#endif
	tsk->splice_pipe = NULL;

	account_kernel_stack(ti, 1);

	return tsk;

out:
	free_thread_info(ti);
	free_task_struct(tsk);
	return NULL;
}

示例#5

/*
 * 由do_fork()调用，为新的子进程创建task_struct, thread_info, 内核栈等信息
 * 创建完成之后和父进程状态完全相同
 */
static struct task_struct *dup_task_struct(struct task_struct *orig)
{
	struct task_struct *tsk;
	struct thread_info *ti;
	unsigned long *stackend;

	int err;

	prepare_to_copy(orig);
	/* 申请task_struct内存空间 */
	tsk = alloc_task_struct();
	if (!tsk)
		return NULL;

	/* 申请thread_info内存空间 */
	ti = alloc_thread_info(tsk);
	if (!ti) {
		/* 失败需要释放前面已经成功申请的task_struct内存空间，防止内存泄漏 */
		free_task_struct(tsk);
		return NULL;
	}
	/* 复制orig进程的信息到tsk进程中，复制完成后地址空间地址相同 */
 	err = arch_dup_task_struct(tsk, orig);
	if (err)
		goto out;

	tsk->stack = ti;

	/* 清空新进程的部分标志 */
	err = prop_local_init_single(&tsk->dirties);
	if (err)
		goto out;
	/* 新进程的进程栈信息 */
	setup_thread_stack(tsk, orig);
	/* 清除进程栈的部分信息 */
	clear_user_return_notifier(tsk);
	clear_tsk_need_resched(tsk);
	stackend = end_of_stack(tsk);
	*stackend = STACK_END_MAGIC;	/* 用作内存越界检测 */

#ifdef CONFIG_CC_STACKPROTECTOR
	tsk->stack_canary = get_random_int();
#endif

	/* One for us, one for whoever does the "release_task()" (usually parent) */
	atomic_set(&tsk->usage,2);
	atomic_set(&tsk->fs_excl, 0);
#ifdef CONFIG_BLK_DEV_IO_TRACE
	tsk->btrace_seq = 0;
#endif
	tsk->splice_pipe = NULL;
	/* 内核栈??? 干啥的??? */
	account_kernel_stack(ti, 1);

	return tsk;

out:
	free_thread_info(ti);
	free_task_struct(tsk);
	return NULL;
}