1 /* SPDX-License-Identifier: GPL-2.0 */
26  * The owner ship rules for task->ptrace which holds the ptrace
27  * flags is simple.  When a task is running it owns it's task->ptrace
28  * flags.  When the a task is stopped the ptracer owns task->ptrace.
75  * ptrace_may_access - check whether the caller is permitted to access
78  * @mode: selects type of access and caller credentials
83  * be set in @mode to specify whether the access was requested through
88 extern bool ptrace_may_access(struct task_struct *task, unsigned int mode);
92 	return !same_thread_group(child->real_parent, child->parent);  in ptrace_reparented()
97 	if (unlikely(child->ptrace))  in ptrace_unlink()
107  * ptrace_parent - return the task that is tracing the given task
119 	if (unlikely(task->ptrace))  in ptrace_parent()
120 		return rcu_dereference(task->parent);  in ptrace_parent()
125  * ptrace_event_enabled - test whether a ptrace event is enabled
135 	return task->ptrace & PT_EVENT_FLAG(event);  in ptrace_event_enabled()
139  * ptrace_event - possibly stop for a ptrace event notification
150 	if (unlikely(ptrace_event_enabled(current, event))) {  in ptrace_event()
154 		if ((current->ptrace & (PT_PTRACED|PT_SEIZED)) == PT_PTRACED)  in ptrace_event()
155 			send_sig(SIGTRAP, current, 0);  in ptrace_event()
160  * ptrace_event_pid - possibly stop for a ptrace event notification
182 	ns = task_active_pid_ns(rcu_dereference(current->parent));  in ptrace_event_pid()
191  * ptrace_init_task - initialize ptrace state for a new child
198  * Called with current's siglock and write_lock_irq(&tasklist_lock) held.
202 	INIT_LIST_HEAD(&child->ptrace_entry);  in ptrace_init_task()
203 	INIT_LIST_HEAD(&child->ptraced);  in ptrace_init_task()
204 	child->jobctl = 0;  in ptrace_init_task()
205 	child->ptrace = 0;  in ptrace_init_task()
206 	child->parent = child->real_parent;  in ptrace_init_task()
208 	if (unlikely(ptrace) && current->ptrace) {  in ptrace_init_task()
209 		child->ptrace = current->ptrace;  in ptrace_init_task()
210 		__ptrace_link(child, current->parent, current->ptracer_cred);  in ptrace_init_task()
212 		if (child->ptrace & PT_SEIZED)  in ptrace_init_task()
215 			sigaddset(&child->pending.signal, SIGSTOP);  in ptrace_init_task()
218 		child->ptracer_cred = NULL;  in ptrace_init_task()
222  * ptrace_release_task - final ptrace-related cleanup of a zombie being reaped
229 	BUG_ON(!list_empty(&task->ptraced));  in ptrace_release_task()
231 	BUG_ON(!list_empty(&task->ptrace_entry));  in ptrace_release_task()
242  * is a no-op and the spurious error condition needs to be filtered out by some
243  * other means (e.g., in user-level, by passing an extra argument to the
261  * These do-nothing inlines are used when the arch does not
262  * implement single-step.  The kerneldoc comments are here
268  * arch_has_single_step - does this CPU support user-mode single-step?
273  * supports instruction single-step for user mode.
279  * user_enable_single_step - single-step in user-mode task
280  * @task: either current or a task stopped in %TASK_TRACED
283  * Set @task so that when it returns to user mode, it will trap after the
293  * user_disable_single_step - cancel user-mode single-step
294  * @task: either current or a task stopped in %TASK_TRACED
311  * arch_has_block_step - does this CPU support user-mode block-step?
316  * supports step-until-branch for user mode.  It can be a constant or it
322  * user_enable_block_step - step until branch in user-mode task
323  * @task: either current or a task stopped in %TASK_TRACED
326  * and will never be called when single-instruction stepping is being used.
327  * Set @task so that when it returns to user mode, it will trap after the
356  * arch_ptrace_stop_needed - Decide whether arch_ptrace_stop() should be called
363  * superfluous.  For example, if the thread has not been back to user mode
368  * may include arch-specific operations necessary prior to a ptrace stop.
375  * arch_ptrace_stop - Do machine-specific work before stopping for ptrace
379  * access.  The arch can have machine-specific work to be done before
389 #define current_pt_regs() task_pt_regs(current)
393  * unlike current_pt_regs(), this one is equal to task_pt_regs(current)
394  * on *all* architectures; the only reason to have a per-arch definition
398 #define signal_pt_regs() task_pt_regs(current)
414 	int ptrace = current->ptrace;  in ptrace_report_syscall()
426 	 * stopping signal is not SIGTRAP.  -brl  in ptrace_report_syscall()
429 		send_sig(signr, current, 1);  in ptrace_report_syscall()
431 	return fatal_signal_pending(current);  in ptrace_report_syscall()
435  * ptrace_report_syscall_entry - task is about to attempt a system call
436  * @regs:		user register state of current task
439  * %SYSCALL_WORK_SYSCALL_EMU have been set, when the current task has just
447  * made.  If @task ever returns to user mode after this, its register state
450  * can work (see asm-generic/syscall.h).
452  * Called without locks, just after entering kernel mode.
461  * ptrace_report_syscall_exit - task has just finished a system call
462  * @regs:		user register state of current task
463  * @step:		nonzero if simulating single-step or block-step
466  * the current task has just finished an attempted system call.  Full