--- /dev/null
+#ifndef _LINUX_PTRACE_H
+#define _LINUX_PTRACE_H
+
+#include <linux/compiler.h> /* For unlikely. */
+#include <linux/sched.h> /* For struct task_struct. */
+#include <linux/err.h> /* for IS_ERR_VALUE */
+#include <linux/bug.h> /* For BUG_ON. */
+#include <linux/pid_namespace.h> /* For task_active_pid_ns. */
+#include <uapi/linux/ptrace.h>
+
+/*
+ * Ptrace flags
+ *
+ * The owner ship rules for task->ptrace which holds the ptrace
+ * flags is simple. When a task is running it owns it's task->ptrace
+ * flags. When the a task is stopped the ptracer owns task->ptrace.
+ */
+
+#define PT_SEIZED 0x00010000 /* SEIZE used, enable new behavior */
+#define PT_PTRACED 0x00000001
+#define PT_DTRACE 0x00000002 /* delayed trace (used on m68k, i386) */
+#define PT_PTRACE_CAP 0x00000004 /* ptracer can follow suid-exec */
+
+#define PT_OPT_FLAG_SHIFT 3
+/* PT_TRACE_* event enable flags */
+#define PT_EVENT_FLAG(event) (1 << (PT_OPT_FLAG_SHIFT + (event)))
+#define PT_TRACESYSGOOD PT_EVENT_FLAG(0)
+#define PT_TRACE_FORK PT_EVENT_FLAG(PTRACE_EVENT_FORK)
+#define PT_TRACE_VFORK PT_EVENT_FLAG(PTRACE_EVENT_VFORK)
+#define PT_TRACE_CLONE PT_EVENT_FLAG(PTRACE_EVENT_CLONE)
+#define PT_TRACE_EXEC PT_EVENT_FLAG(PTRACE_EVENT_EXEC)
+#define PT_TRACE_VFORK_DONE PT_EVENT_FLAG(PTRACE_EVENT_VFORK_DONE)
+#define PT_TRACE_EXIT PT_EVENT_FLAG(PTRACE_EVENT_EXIT)
+#define PT_TRACE_SECCOMP PT_EVENT_FLAG(PTRACE_EVENT_SECCOMP)
+
+#define PT_EXITKILL (PTRACE_O_EXITKILL << PT_OPT_FLAG_SHIFT)
+
+/* single stepping state bits (used on ARM and PA-RISC) */
+#define PT_SINGLESTEP_BIT 31
+#define PT_SINGLESTEP (1<<PT_SINGLESTEP_BIT)
+#define PT_BLOCKSTEP_BIT 30
+#define PT_BLOCKSTEP (1<<PT_BLOCKSTEP_BIT)
+
+extern long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data);
+extern int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len);
+extern int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len);
+extern void ptrace_disable(struct task_struct *);
+extern int ptrace_request(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data);
+extern void ptrace_notify(int exit_code);
+extern void __ptrace_link(struct task_struct *child,
+ struct task_struct *new_parent);
+extern void __ptrace_unlink(struct task_struct *child);
+extern void exit_ptrace(struct task_struct *tracer, struct list_head *dead);
+#define PTRACE_MODE_READ 0x01
+#define PTRACE_MODE_ATTACH 0x02
+#define PTRACE_MODE_NOAUDIT 0x04
+/* Returns true on success, false on denial. */
+extern bool ptrace_may_access(struct task_struct *task, unsigned int mode);
+
+static inline int ptrace_reparented(struct task_struct *child)
+{
+ return !same_thread_group(child->real_parent, child->parent);
+}
+
+static inline void ptrace_unlink(struct task_struct *child)
+{
+ if (unlikely(child->ptrace))
+ __ptrace_unlink(child);
+}
+
+int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr,
+ unsigned long data);
+int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
+ unsigned long data);
+
+/**
+ * ptrace_parent - return the task that is tracing the given task
+ * @task: task to consider
+ *
+ * Returns %NULL if no one is tracing @task, or the &struct task_struct
+ * pointer to its tracer.
+ *
+ * Must called under rcu_read_lock(). The pointer returned might be kept
+ * live only by RCU. During exec, this may be called with task_lock() held
+ * on @task, still held from when check_unsafe_exec() was called.
+ */
+static inline struct task_struct *ptrace_parent(struct task_struct *task)
+{
+ if (unlikely(task->ptrace))
+ return rcu_dereference(task->parent);
+ return NULL;
+}
+
+/**
+ * ptrace_event_enabled - test whether a ptrace event is enabled
+ * @task: ptracee of interest
+ * @event: %PTRACE_EVENT_* to test
+ *
+ * Test whether @event is enabled for ptracee @task.
+ *
+ * Returns %true if @event is enabled, %false otherwise.
+ */
+static inline bool ptrace_event_enabled(struct task_struct *task, int event)
+{
+ return task->ptrace & PT_EVENT_FLAG(event);
+}
+
+/**
+ * ptrace_event - possibly stop for a ptrace event notification
+ * @event: %PTRACE_EVENT_* value to report
+ * @message: value for %PTRACE_GETEVENTMSG to return
+ *
+ * Check whether @event is enabled and, if so, report @event and @message
+ * to the ptrace parent.
+ *
+ * Called without locks.
+ */
+static inline void ptrace_event(int event, unsigned long message)
+{
+ if (unlikely(ptrace_event_enabled(current, event))) {
+ current->ptrace_message = message;
+ ptrace_notify((event << 8) | SIGTRAP);
+ } else if (event == PTRACE_EVENT_EXEC) {
+ /* legacy EXEC report via SIGTRAP */
+ if ((current->ptrace & (PT_PTRACED|PT_SEIZED)) == PT_PTRACED)
+ send_sig(SIGTRAP, current, 0);
+ }
+}
+
+/**
+ * ptrace_event_pid - possibly stop for a ptrace event notification
+ * @event: %PTRACE_EVENT_* value to report
+ * @pid: process identifier for %PTRACE_GETEVENTMSG to return
+ *
+ * Check whether @event is enabled and, if so, report @event and @pid
+ * to the ptrace parent. @pid is reported as the pid_t seen from the
+ * the ptrace parent's pid namespace.
+ *
+ * Called without locks.
+ */
+static inline void ptrace_event_pid(int event, struct pid *pid)
+{
+ /*
+ * FIXME: There's a potential race if a ptracer in a different pid
+ * namespace than parent attaches between computing message below and
+ * when we acquire tasklist_lock in ptrace_stop(). If this happens,
+ * the ptracer will get a bogus pid from PTRACE_GETEVENTMSG.
+ */
+ unsigned long message = 0;
+ struct pid_namespace *ns;
+
+ rcu_read_lock();
+ ns = task_active_pid_ns(rcu_dereference(current->parent));
+ if (ns)
+ message = pid_nr_ns(pid, ns);
+ rcu_read_unlock();
+
+ ptrace_event(event, message);
+}
+
+/**
+ * ptrace_init_task - initialize ptrace state for a new child
+ * @child: new child task
+ * @ptrace: true if child should be ptrace'd by parent's tracer
+ *
+ * This is called immediately after adding @child to its parent's children
+ * list. @ptrace is false in the normal case, and true to ptrace @child.
+ *
+ * Called with current's siglock and write_lock_irq(&tasklist_lock) held.
+ */
+static inline void ptrace_init_task(struct task_struct *child, bool ptrace)
+{
+ INIT_LIST_HEAD(&child->ptrace_entry);
+ INIT_LIST_HEAD(&child->ptraced);
+ child->jobctl = 0;
+ child->ptrace = 0;
+ child->parent = child->real_parent;
+
+ if (unlikely(ptrace) && current->ptrace) {
+ child->ptrace = current->ptrace;
+ __ptrace_link(child, current->parent);
+
+ if (child->ptrace & PT_SEIZED)
+ task_set_jobctl_pending(child, JOBCTL_TRAP_STOP);
+ else
+ sigaddset(&child->pending.signal, SIGSTOP);
+
+ set_tsk_thread_flag(child, TIF_SIGPENDING);
+ }
+}
+
+/**
+ * ptrace_release_task - final ptrace-related cleanup of a zombie being reaped
+ * @task: task in %EXIT_DEAD state
+ *
+ * Called with write_lock(&tasklist_lock) held.
+ */
+static inline void ptrace_release_task(struct task_struct *task)
+{
+ BUG_ON(!list_empty(&task->ptraced));
+ ptrace_unlink(task);
+ BUG_ON(!list_empty(&task->ptrace_entry));
+}
+
+#ifndef force_successful_syscall_return
+/*
+ * System call handlers that, upon successful completion, need to return a
+ * negative value should call force_successful_syscall_return() right before
+ * returning. On architectures where the syscall convention provides for a
+ * separate error flag (e.g., alpha, ia64, ppc{,64}, sparc{,64}, possibly
+ * others), this macro can be used to ensure that the error flag will not get
+ * set. On architectures which do not support a separate error flag, the macro
+ * is a no-op and the spurious error condition needs to be filtered out by some
+ * other means (e.g., in user-level, by passing an extra argument to the
+ * syscall handler, or something along those lines).
+ */
+#define force_successful_syscall_return() do { } while (0)
+#endif
+
+#ifndef is_syscall_success
+/*
+ * On most systems we can tell if a syscall is a success based on if the retval
+ * is an error value. On some systems like ia64 and powerpc they have different
+ * indicators of success/failure and must define their own.
+ */
+#define is_syscall_success(regs) (!IS_ERR_VALUE((unsigned long)(regs_return_value(regs))))
+#endif
+
+/*
+ * <asm/ptrace.h> should define the following things inside #ifdef __KERNEL__.
+ *
+ * These do-nothing inlines are used when the arch does not
+ * implement single-step. The kerneldoc comments are here
+ * to document the interface for all arch definitions.
+ */
+
+#ifndef arch_has_single_step
+/**
+ * arch_has_single_step - does this CPU support user-mode single-step?
+ *
+ * If this is defined, then there must be function declarations or
+ * inlines for user_enable_single_step() and user_disable_single_step().
+ * arch_has_single_step() should evaluate to nonzero iff the machine
+ * supports instruction single-step for user mode.
+ * It can be a constant or it can test a CPU feature bit.
+ */
+#define arch_has_single_step() (0)
+
+/**
+ * user_enable_single_step - single-step in user-mode task
+ * @task: either current or a task stopped in %TASK_TRACED
+ *
+ * This can only be called when arch_has_single_step() has returned nonzero.
+ * Set @task so that when it returns to user mode, it will trap after the
+ * next single instruction executes. If arch_has_block_step() is defined,
+ * this must clear the effects of user_enable_block_step() too.
+ */
+static inline void user_enable_single_step(struct task_struct *task)
+{
+ BUG(); /* This can never be called. */
+}
+
+/**
+ * user_disable_single_step - cancel user-mode single-step
+ * @task: either current or a task stopped in %TASK_TRACED
+ *
+ * Clear @task of the effects of user_enable_single_step() and
+ * user_enable_block_step(). This can be called whether or not either
+ * of those was ever called on @task, and even if arch_has_single_step()
+ * returned zero.
+ */
+static inline void user_disable_single_step(struct task_struct *task)
+{
+}
+#else
+extern void user_enable_single_step(struct task_struct *);
+extern void user_disable_single_step(struct task_struct *);
+#endif /* arch_has_single_step */
+
+#ifndef arch_has_block_step
+/**
+ * arch_has_block_step - does this CPU support user-mode block-step?
+ *
+ * If this is defined, then there must be a function declaration or inline
+ * for user_enable_block_step(), and arch_has_single_step() must be defined
+ * too. arch_has_block_step() should evaluate to nonzero iff the machine
+ * supports step-until-branch for user mode. It can be a constant or it
+ * can test a CPU feature bit.
+ */
+#define arch_has_block_step() (0)
+
+/**
+ * user_enable_block_step - step until branch in user-mode task
+ * @task: either current or a task stopped in %TASK_TRACED
+ *
+ * This can only be called when arch_has_block_step() has returned nonzero,
+ * and will never be called when single-instruction stepping is being used.
+ * Set @task so that when it returns to user mode, it will trap after the
+ * next branch or trap taken.
+ */
+static inline void user_enable_block_step(struct task_struct *task)
+{
+ BUG(); /* This can never be called. */
+}
+#else
+extern void user_enable_block_step(struct task_struct *);
+#endif /* arch_has_block_step */
+
+#ifdef ARCH_HAS_USER_SINGLE_STEP_INFO
+extern void user_single_step_siginfo(struct task_struct *tsk,
+ struct pt_regs *regs, siginfo_t *info);
+#else
+static inline void user_single_step_siginfo(struct task_struct *tsk,
+ struct pt_regs *regs, siginfo_t *info)
+{
+ memset(info, 0, sizeof(*info));
+ info->si_signo = SIGTRAP;
+}
+#endif
+
+#ifndef arch_ptrace_stop_needed
+/**
+ * arch_ptrace_stop_needed - Decide whether arch_ptrace_stop() should be called
+ * @code: current->exit_code value ptrace will stop with
+ * @info: siginfo_t pointer (or %NULL) for signal ptrace will stop with
+ *
+ * This is called with the siglock held, to decide whether or not it's
+ * necessary to release the siglock and call arch_ptrace_stop() with the
+ * same @code and @info arguments. It can be defined to a constant if
+ * arch_ptrace_stop() is never required, or always is. On machines where
+ * this makes sense, it should be defined to a quick test to optimize out
+ * calling arch_ptrace_stop() when it would be superfluous. For example,
+ * if the thread has not been back to user mode since the last stop, the
+ * thread state might indicate that nothing needs to be done.
+ *
+ * This is guaranteed to be invoked once before a task stops for ptrace and
+ * may include arch-specific operations necessary prior to a ptrace stop.
+ */
+#define arch_ptrace_stop_needed(code, info) (0)
+#endif
+
+#ifndef arch_ptrace_stop
+/**
+ * arch_ptrace_stop - Do machine-specific work before stopping for ptrace
+ * @code: current->exit_code value ptrace will stop with
+ * @info: siginfo_t pointer (or %NULL) for signal ptrace will stop with
+ *
+ * This is called with no locks held when arch_ptrace_stop_needed() has
+ * just returned nonzero. It is allowed to block, e.g. for user memory
+ * access. The arch can have machine-specific work to be done before
+ * ptrace stops. On ia64, register backing store gets written back to user
+ * memory here. Since this can be costly (requires dropping the siglock),
+ * we only do it when the arch requires it for this particular stop, as
+ * indicated by arch_ptrace_stop_needed().
+ */
+#define arch_ptrace_stop(code, info) do { } while (0)
+#endif
+
+#ifndef current_pt_regs
+#define current_pt_regs() task_pt_regs(current)
+#endif
+
+#ifndef ptrace_signal_deliver
+#define ptrace_signal_deliver() ((void)0)
+#endif
+
+/*
+ * unlike current_pt_regs(), this one is equal to task_pt_regs(current)
+ * on *all* architectures; the only reason to have a per-arch definition
+ * is optimisation.
+ */
+#ifndef signal_pt_regs
+#define signal_pt_regs() task_pt_regs(current)
+#endif
+
+#ifndef current_user_stack_pointer
+#define current_user_stack_pointer() user_stack_pointer(current_pt_regs())
+#endif
+
+extern int task_current_syscall(struct task_struct *target, long *callno,
+ unsigned long args[6], unsigned int maxargs,
+ unsigned long *sp, unsigned long *pc);
+
+#endif
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