Initial import

1 files changed, 386 insertions, 0 deletions

diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
new file mode 100644
index 000000000..987a73a40
--- /dev/null
+++ b/include/linux/ptrace.h
@@ -0,0 +1,386 @@
+#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