[mirror_ubuntu-bionic-kernel.git] / include / linux / ptrace.h

#ifndef _LINUX_PTRACE_H
#define _LINUX_PTRACE_H
/* ptrace.h */
/* structs and defines to help the user use the ptrace system call. */

/* has the defines to get at the registers. */

#define PTRACE_TRACEME		   0
#define PTRACE_PEEKTEXT		   1
#define PTRACE_PEEKDATA		   2
#define PTRACE_PEEKUSR		   3
#define PTRACE_POKETEXT		   4
#define PTRACE_POKEDATA		   5
#define PTRACE_POKEUSR		   6
#define PTRACE_CONT		   7
#define PTRACE_KILL		   8
#define PTRACE_SINGLESTEP	   9

#define PTRACE_ATTACH		  16
#define PTRACE_DETACH		  17

#define PTRACE_SYSCALL		  24

/* 0x4200-0x4300 are reserved for architecture-independent additions.  */
#define PTRACE_SETOPTIONS	0x4200
#define PTRACE_GETEVENTMSG	0x4201
#define PTRACE_GETSIGINFO	0x4202
#define PTRACE_SETSIGINFO	0x4203

/*
 * Generic ptrace interface that exports the architecture specific regsets
 * using the corresponding NT_* types (which are also used in the core dump).
 * Please note that the NT_PRSTATUS note type in a core dump contains a full
 * 'struct elf_prstatus'. But the user_regset for NT_PRSTATUS contains just the
 * elf_gregset_t that is the pr_reg field of 'struct elf_prstatus'. For all the
 * other user_regset flavors, the user_regset layout and the ELF core dump note
 * payload are exactly the same layout.
 *
 * This interface usage is as follows:
 *	struct iovec iov = { buf, len};
 *
 *	ret = ptrace(PTRACE_GETREGSET/PTRACE_SETREGSET, pid, NT_XXX_TYPE, &iov);
 *
 * On the successful completion, iov.len will be updated by the kernel,
 * specifying how much the kernel has written/read to/from the user's iov.buf.
 */
#define PTRACE_GETREGSET	0x4204
#define PTRACE_SETREGSET	0x4205

#define PTRACE_SEIZE		0x4206
#define PTRACE_INTERRUPT	0x4207
#define PTRACE_LISTEN		0x4208

/* Wait extended result codes for the above trace options.  */
#define PTRACE_EVENT_FORK	1
#define PTRACE_EVENT_VFORK	2
#define PTRACE_EVENT_CLONE	3
#define PTRACE_EVENT_EXEC	4
#define PTRACE_EVENT_VFORK_DONE	5
#define PTRACE_EVENT_EXIT	6
/* Extended result codes which enabled by means other than options.  */
#define PTRACE_EVENT_STOP	128

/* Options set using PTRACE_SETOPTIONS or using PTRACE_SEIZE @data param */
#define PTRACE_O_TRACESYSGOOD	1
#define PTRACE_O_TRACEFORK	(1 << PTRACE_EVENT_FORK)
#define PTRACE_O_TRACEVFORK	(1 << PTRACE_EVENT_VFORK)
#define PTRACE_O_TRACECLONE	(1 << PTRACE_EVENT_CLONE)
#define PTRACE_O_TRACEEXEC	(1 << PTRACE_EVENT_EXEC)
#define PTRACE_O_TRACEVFORKDONE	(1 << PTRACE_EVENT_VFORK_DONE)
#define PTRACE_O_TRACEEXIT	(1 << PTRACE_EVENT_EXIT)

#define PTRACE_O_MASK		0x0000007f

#include <asm/ptrace.h>

#ifdef __KERNEL__
/*
 * 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)

/* 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)

#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.  */


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_check_attach(struct task_struct *task, bool ignore_state);
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);
#define PTRACE_MODE_READ	0x01
#define PTRACE_MODE_ATTACH	0x02
#define PTRACE_MODE_NOAUDIT	0x04
/* Returns 0 on success, -errno on denial. */
extern int __ptrace_may_access(struct task_struct *task, unsigned int mode);
/* 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_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);
#ifdef CONFIG_HAVE_HW_BREAKPOINT
	atomic_set(&child->ptrace_bp_refcnt, 1);
#endif
	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.
 */
#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

extern int task_current_syscall(struct task_struct *target, long *callno,
				unsigned long args[6], unsigned int maxargs,
				unsigned long *sp, unsigned long *pc);

#ifdef CONFIG_HAVE_HW_BREAKPOINT
extern int ptrace_get_breakpoints(struct task_struct *tsk);
extern void ptrace_put_breakpoints(struct task_struct *tsk);
#else
static inline void ptrace_put_breakpoints(struct task_struct *tsk) { }
#endif /* CONFIG_HAVE_HW_BREAKPOINT */

#endif /* __KERNEL */

#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_PTRACE_H
	2	#define _LINUX_PTRACE_H
	3	/* ptrace.h */
	4	/* structs and defines to help the user use the ptrace system call. */
	5
	6	/* has the defines to get at the registers. */
	7
	8	#define PTRACE_TRACEME 0
	9	#define PTRACE_PEEKTEXT 1
	10	#define PTRACE_PEEKDATA 2
	11	#define PTRACE_PEEKUSR 3
	12	#define PTRACE_POKETEXT 4
	13	#define PTRACE_POKEDATA 5
	14	#define PTRACE_POKEUSR 6
	15	#define PTRACE_CONT 7
	16	#define PTRACE_KILL 8
	17	#define PTRACE_SINGLESTEP 9
	18
416bc512 RM	19	#define PTRACE_ATTACH 16
416bc512 RM	20	#define PTRACE_DETACH 17
1da177e4 LT	21
	22	#define PTRACE_SYSCALL 24
	23
	24	/* 0x4200-0x4300 are reserved for architecture-independent additions. */
	25	#define PTRACE_SETOPTIONS 0x4200
	26	#define PTRACE_GETEVENTMSG 0x4201
	27	#define PTRACE_GETSIGINFO 0x4202
	28	#define PTRACE_SETSIGINFO 0x4203
	29
2225a122 SS	30	/*
	31	* Generic ptrace interface that exports the architecture specific regsets
	32	* using the corresponding NT_* types (which are also used in the core dump).
c6a0dd7e SS	33	* Please note that the NT_PRSTATUS note type in a core dump contains a full
	34	* 'struct elf_prstatus'. But the user_regset for NT_PRSTATUS contains just the
	35	* elf_gregset_t that is the pr_reg field of 'struct elf_prstatus'. For all the
	36	* other user_regset flavors, the user_regset layout and the ELF core dump note
	37	* payload are exactly the same layout.
2225a122 SS	38	*
	39	* This interface usage is as follows:
	40	* struct iovec iov = { buf, len};
	41	*
	42	* ret = ptrace(PTRACE_GETREGSET/PTRACE_SETREGSET, pid, NT_XXX_TYPE, &iov);
	43	*
	44	* On the successful completion, iov.len will be updated by the kernel,
	45	* specifying how much the kernel has written/read to/from the user's iov.buf.
	46	*/
	47	#define PTRACE_GETREGSET 0x4204
	48	#define PTRACE_SETREGSET 0x4205
	49
3544d72a	50	#define PTRACE_SEIZE 0x4206
fca26f26	51	#define PTRACE_INTERRUPT 0x4207
544b2c91	52	#define PTRACE_LISTEN 0x4208
3544d72a	53
1da177e4 LT	54	/* Wait extended result codes for the above trace options. */
	55	#define PTRACE_EVENT_FORK 1
	56	#define PTRACE_EVENT_VFORK 2
	57	#define PTRACE_EVENT_CLONE 3
	58	#define PTRACE_EVENT_EXEC 4
	59	#define PTRACE_EVENT_VFORK_DONE 5
	60	#define PTRACE_EVENT_EXIT 6
5cdf389a DV	61	/* Extended result codes which enabled by means other than options. */
5cdf389a DV	62	#define PTRACE_EVENT_STOP 128
1da177e4	63
ee00560c	64	/* Options set using PTRACE_SETOPTIONS or using PTRACE_SEIZE @data param */
86b6c1f3 DV	65	#define PTRACE_O_TRACESYSGOOD 1
	66	#define PTRACE_O_TRACEFORK (1 << PTRACE_EVENT_FORK)
	67	#define PTRACE_O_TRACEVFORK (1 << PTRACE_EVENT_VFORK)
	68	#define PTRACE_O_TRACECLONE (1 << PTRACE_EVENT_CLONE)
	69	#define PTRACE_O_TRACEEXEC (1 << PTRACE_EVENT_EXEC)
	70	#define PTRACE_O_TRACEVFORKDONE (1 << PTRACE_EVENT_VFORK_DONE)
	71	#define PTRACE_O_TRACEEXIT (1 << PTRACE_EVENT_EXIT)
	72
	73	#define PTRACE_O_MASK 0x0000007f
	74
1da177e4 LT	75	#include <asm/ptrace.h>
	76
	77	#ifdef __KERNEL__
	78	/*
	79	* Ptrace flags
260ea101 EB	80	*
	81	* The owner ship rules for task->ptrace which holds the ptrace
	82	* flags is simple. When a task is running it owns it's task->ptrace
	83	* flags. When the a task is stopped the ptracer owns task->ptrace.
1da177e4 LT	84	*/
1da177e4 LT	85
3544d72a	86	#define PT_SEIZED 0x00010000 /* SEIZE used, enable new behavior */
1da177e4 LT	87	#define PT_PTRACED 0x00000001
1da177e4 LT	88	#define PT_DTRACE 0x00000002 /* delayed trace (used on m68k, i386) */
86b6c1f3	89	#define PT_PTRACE_CAP 0x00000004 /* ptracer can follow suid-exec */
643ad838	90
86b6c1f3	91	#define PT_OPT_FLAG_SHIFT 3
643ad838	92	/* PT_TRACE_* event enable flags */
86b6c1f3 DV	93	#define PT_EVENT_FLAG(event) (1 << (PT_OPT_FLAG_SHIFT + (event)))
86b6c1f3 DV	94	#define PT_TRACESYSGOOD PT_EVENT_FLAG(0)
643ad838 TH	95	#define PT_TRACE_FORK PT_EVENT_FLAG(PTRACE_EVENT_FORK)
	96	#define PT_TRACE_VFORK PT_EVENT_FLAG(PTRACE_EVENT_VFORK)
	97	#define PT_TRACE_CLONE PT_EVENT_FLAG(PTRACE_EVENT_CLONE)
	98	#define PT_TRACE_EXEC PT_EVENT_FLAG(PTRACE_EVENT_EXEC)
	99	#define PT_TRACE_VFORK_DONE PT_EVENT_FLAG(PTRACE_EVENT_VFORK_DONE)
	100	#define PT_TRACE_EXIT PT_EVENT_FLAG(PTRACE_EVENT_EXIT)
1da177e4	101
1da177e4 LT	102	/* single stepping state bits (used on ARM and PA-RISC) */
	103	#define PT_SINGLESTEP_BIT 31
	104	#define PT_SINGLESTEP (1<<PT_SINGLESTEP_BIT)
	105	#define PT_BLOCKSTEP_BIT 30
	106	#define PT_BLOCKSTEP (1<<PT_BLOCKSTEP_BIT)
	107
	108	#include <linux/compiler.h> /* For unlikely. */
	109	#include <linux/sched.h> /* For struct task_struct. */
d7e7528b	110	#include <linux/err.h> /* for IS_ERR_VALUE */
187f1882	111	#include <linux/bug.h> /* For BUG_ON. */
1da177e4	112
481bed45	113
9b05a69e NK	114	extern long arch_ptrace(struct task_struct *child, long request,
9b05a69e NK	115	unsigned long addr, unsigned long data);
1da177e4 LT	116	extern int ptrace_readdata(struct task_struct tsk, unsigned long src, char __user dst, int len);
1da177e4 LT	117	extern int ptrace_writedata(struct task_struct tsk, char __user src, unsigned long dst, int len);
1da177e4	118	extern void ptrace_disable(struct task_struct *);
755e276b	119	extern int ptrace_check_attach(struct task_struct *task, bool ignore_state);
4abf9869 NK	120	extern int ptrace_request(struct task_struct *child, long request,
4abf9869 NK	121	unsigned long addr, unsigned long data);
1da177e4 LT	122	extern void ptrace_notify(int exit_code);
	123	extern void __ptrace_link(struct task_struct *child,
	124	struct task_struct *new_parent);
	125	extern void __ptrace_unlink(struct task_struct *child);
39c626ae	126	extern void exit_ptrace(struct task_struct *tracer);
69f594a3 EP	127	#define PTRACE_MODE_READ 0x01
	128	#define PTRACE_MODE_ATTACH 0x02
	129	#define PTRACE_MODE_NOAUDIT 0x04
006ebb40 SS	130	/* Returns 0 on success, -errno on denial. */
	131	extern int __ptrace_may_access(struct task_struct *task, unsigned int mode);
	132	/* Returns true on success, false on denial. */
	133	extern bool ptrace_may_access(struct task_struct *task, unsigned int mode);
1da177e4	134
53b6f9fb ON	135	static inline int ptrace_reparented(struct task_struct *child)
53b6f9fb ON	136	{
0347e177	137	return !same_thread_group(child->real_parent, child->parent);
53b6f9fb	138	}
c6a47cc2	139
1da177e4 LT	140	static inline void ptrace_unlink(struct task_struct *child)
	141	{
	142	if (unlikely(child->ptrace))
	143	__ptrace_unlink(child);
	144	}
	145
4abf9869 NK	146	int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr,
	147	unsigned long data);
	148	int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
	149	unsigned long data);
1da177e4	150
06d98473 TH	151	/**
	152	* ptrace_parent - return the task that is tracing the given task
	153	* @task: task to consider
	154	*
	155	* Returns %NULL if no one is tracing @task, or the &struct task_struct
	156	* pointer to its tracer.
	157	*
	158	* Must called under rcu_read_lock(). The pointer returned might be kept
	159	* live only by RCU. During exec, this may be called with task_lock() held
	160	* on @task, still held from when check_unsafe_exec() was called.
	161	*/
	162	static inline struct task_struct ptrace_parent(struct task_struct task)
	163	{
	164	if (unlikely(task->ptrace))
	165	return rcu_dereference(task->parent);
	166	return NULL;
	167	}
	168
643ad838 TH	169	/**
	170	* ptrace_event_enabled - test whether a ptrace event is enabled
	171	* @task: ptracee of interest
	172	* @event: %PTRACE_EVENT_* to test
	173	*
	174	* Test whether @event is enabled for ptracee @task.
	175	*
	176	* Returns %true if @event is enabled, %false otherwise.
	177	*/
	178	static inline bool ptrace_event_enabled(struct task_struct *task, int event)
	179	{
	180	return task->ptrace & PT_EVENT_FLAG(event);
	181	}
	182
88ac2921 RM	183	/**
88ac2921 RM	184	* ptrace_event - possibly stop for a ptrace event notification
643ad838	185	* @event: %PTRACE_EVENT_* value to report
88ac2921 RM	186	* @message: value for %PTRACE_GETEVENTMSG to return
88ac2921 RM	187	*
643ad838 TH	188	* Check whether @event is enabled and, if so, report @event and @message
643ad838 TH	189	* to the ptrace parent.
88ac2921	190	*
88ac2921 RM	191	* Called without locks.
88ac2921 RM	192	*/
f3c04b93	193	static inline void ptrace_event(int event, unsigned long message)
88ac2921	194	{
f3c04b93 TH	195	if (unlikely(ptrace_event_enabled(current, event))) {
	196	current->ptrace_message = message;
	197	ptrace_notify((event << 8) \| SIGTRAP);
b1845ff5	198	} else if (event == PTRACE_EVENT_EXEC) {
f3c04b93	199	/* legacy EXEC report via SIGTRAP */
b1845ff5 ON	200	if ((current->ptrace & (PT_PTRACED\|PT_SEIZED)) == PT_PTRACED)
b1845ff5 ON	201	send_sig(SIGTRAP, current, 0);
f3c04b93	202	}
88ac2921 RM	203	}
88ac2921 RM	204
09a05394 RM	205	/**
	206	* ptrace_init_task - initialize ptrace state for a new child
	207	* @child: new child task
	208	* @ptrace: true if child should be ptrace'd by parent's tracer
	209	*
	210	* This is called immediately after adding @child to its parent's children
	211	* list. @ptrace is false in the normal case, and true to ptrace @child.
	212	*
	213	* Called with current's siglock and write_lock_irq(&tasklist_lock) held.
	214	*/
	215	static inline void ptrace_init_task(struct task_struct *child, bool ptrace)
	216	{
	217	INIT_LIST_HEAD(&child->ptrace_entry);
	218	INIT_LIST_HEAD(&child->ptraced);
6634ae10 ON	219	#ifdef CONFIG_HAVE_HW_BREAKPOINT
	220	atomic_set(&child->ptrace_bp_refcnt, 1);
	221	#endif
	222	child->jobctl = 0;
09a05394	223	child->ptrace = 0;
6634ae10 ON	224	child->parent = child->real_parent;
	225
	226	if (unlikely(ptrace) && current->ptrace) {
09a05394	227	child->ptrace = current->ptrace;
c6a47cc2	228	__ptrace_link(child, current->parent);
dcace06c	229
d184d6eb ON	230	if (child->ptrace & PT_SEIZED)
	231	task_set_jobctl_pending(child, JOBCTL_TRAP_STOP);
	232	else
	233	sigaddset(&child->pending.signal, SIGSTOP);
	234
dcace06c	235	set_tsk_thread_flag(child, TIF_SIGPENDING);
09a05394 RM	236	}
	237	}
	238
dae33574 RM	239	/**
	240	* ptrace_release_task - final ptrace-related cleanup of a zombie being reaped
	241	* @task: task in %EXIT_DEAD state
	242	*
	243	* Called with write_lock(&tasklist_lock) held.
	244	*/
	245	static inline void ptrace_release_task(struct task_struct *task)
	246	{
	247	BUG_ON(!list_empty(&task->ptraced));
	248	ptrace_unlink(task);
	249	BUG_ON(!list_empty(&task->ptrace_entry));
	250	}
	251
1da177e4 LT	252	#ifndef force_successful_syscall_return
	253	/*
	254	* System call handlers that, upon successful completion, need to return a
	255	* negative value should call force_successful_syscall_return() right before
	256	* returning. On architectures where the syscall convention provides for a
	257	* separate error flag (e.g., alpha, ia64, ppc{,64}, sparc{,64}, possibly
	258	* others), this macro can be used to ensure that the error flag will not get
	259	* set. On architectures which do not support a separate error flag, the macro
	260	* is a no-op and the spurious error condition needs to be filtered out by some
	261	* other means (e.g., in user-level, by passing an extra argument to the
	262	* syscall handler, or something along those lines).
	263	*/
	264	#define force_successful_syscall_return() do { } while (0)
	265	#endif
	266
d7e7528b EP	267	#ifndef is_syscall_success
	268	/*
	269	* On most systems we can tell if a syscall is a success based on if the retval
	270	* is an error value. On some systems like ia64 and powerpc they have different
	271	* indicators of success/failure and must define their own.
	272	*/
	273	#define is_syscall_success(regs) (!IS_ERR_VALUE((unsigned long)(regs_return_value(regs))))
	274	#endif
	275
fb7fa8f1 RM	276	/*
	277	* <asm/ptrace.h> should define the following things inside #ifdef __KERNEL__.
	278	*
	279	* These do-nothing inlines are used when the arch does not
	280	* implement single-step. The kerneldoc comments are here
	281	* to document the interface for all arch definitions.
	282	*/
	283
	284	#ifndef arch_has_single_step
	285	/**
	286	* arch_has_single_step - does this CPU support user-mode single-step?
	287	*
	288	* If this is defined, then there must be function declarations or
	289	* inlines for user_enable_single_step() and user_disable_single_step().
	290	* arch_has_single_step() should evaluate to nonzero iff the machine
	291	* supports instruction single-step for user mode.
	292	* It can be a constant or it can test a CPU feature bit.
	293	*/
	294	#define arch_has_single_step() (0)
	295
	296	/**
	297	* user_enable_single_step - single-step in user-mode task
	298	* @task: either current or a task stopped in %TASK_TRACED
	299	*
	300	* This can only be called when arch_has_single_step() has returned nonzero.
	301	* Set @task so that when it returns to user mode, it will trap after the
dc802c2d RM	302	* next single instruction executes. If arch_has_block_step() is defined,
dc802c2d RM	303	* this must clear the effects of user_enable_block_step() too.
fb7fa8f1 RM	304	*/
	305	static inline void user_enable_single_step(struct task_struct *task)
	306	{
	307	BUG(); /* This can never be called. */
	308	}
	309
	310	/**
	311	* user_disable_single_step - cancel user-mode single-step
	312	* @task: either current or a task stopped in %TASK_TRACED
	313	*
dc802c2d RM	314	* Clear @task of the effects of user_enable_single_step() and
	315	* user_enable_block_step(). This can be called whether or not either
	316	* of those was ever called on @task, and even if arch_has_single_step()
	317	* returned zero.
fb7fa8f1 RM	318	*/
	319	static inline void user_disable_single_step(struct task_struct *task)
	320	{
	321	}
dacbe41f CH	322	#else
	323	extern void user_enable_single_step(struct task_struct *);
	324	extern void user_disable_single_step(struct task_struct *);
fb7fa8f1 RM	325	#endif /* arch_has_single_step */
fb7fa8f1 RM	326
dc802c2d RM	327	#ifndef arch_has_block_step
	328	/**
	329	* arch_has_block_step - does this CPU support user-mode block-step?
	330	*
	331	* If this is defined, then there must be a function declaration or inline
	332	* for user_enable_block_step(), and arch_has_single_step() must be defined
	333	* too. arch_has_block_step() should evaluate to nonzero iff the machine
	334	* supports step-until-branch for user mode. It can be a constant or it
	335	* can test a CPU feature bit.
	336	*/
5b88abbf	337	#define arch_has_block_step() (0)
dc802c2d RM	338
	339	/**
	340	* user_enable_block_step - step until branch in user-mode task
	341	* @task: either current or a task stopped in %TASK_TRACED
	342	*
	343	* This can only be called when arch_has_block_step() has returned nonzero,
	344	* and will never be called when single-instruction stepping is being used.
	345	* Set @task so that when it returns to user mode, it will trap after the
	346	* next branch or trap taken.
	347	*/
	348	static inline void user_enable_block_step(struct task_struct *task)
	349	{
	350	BUG(); /* This can never be called. */
	351	}
dacbe41f CH	352	#else
dacbe41f CH	353	extern void user_enable_block_step(struct task_struct *);
dc802c2d RM	354	#endif /* arch_has_block_step */
dc802c2d RM	355
85ec7fd9 ON	356	#ifdef ARCH_HAS_USER_SINGLE_STEP_INFO
	357	extern void user_single_step_siginfo(struct task_struct *tsk,
	358	struct pt_regs regs, siginfo_t info);
	359	#else
	360	static inline void user_single_step_siginfo(struct task_struct *tsk,
	361	struct pt_regs regs, siginfo_t info)
	362	{
	363	memset(info, 0, sizeof(*info));
	364	info->si_signo = SIGTRAP;
	365	}
	366	#endif
	367
1a669c2f RM	368	#ifndef arch_ptrace_stop_needed
	369	/**
	370	* arch_ptrace_stop_needed - Decide whether arch_ptrace_stop() should be called
	371	* @code: current->exit_code value ptrace will stop with
	372	* @info: siginfo_t pointer (or %NULL) for signal ptrace will stop with
	373	*
	374	* This is called with the siglock held, to decide whether or not it's
	375	* necessary to release the siglock and call arch_ptrace_stop() with the
	376	* same @code and @info arguments. It can be defined to a constant if
	377	* arch_ptrace_stop() is never required, or always is. On machines where
	378	* this makes sense, it should be defined to a quick test to optimize out
	379	* calling arch_ptrace_stop() when it would be superfluous. For example,
	380	* if the thread has not been back to user mode since the last stop, the
	381	* thread state might indicate that nothing needs to be done.
	382	*/
	383	#define arch_ptrace_stop_needed(code, info) (0)
	384	#endif
	385
	386	#ifndef arch_ptrace_stop
	387	/**
	388	* arch_ptrace_stop - Do machine-specific work before stopping for ptrace
	389	* @code: current->exit_code value ptrace will stop with
	390	* @info: siginfo_t pointer (or %NULL) for signal ptrace will stop with
	391	*
	392	* This is called with no locks held when arch_ptrace_stop_needed() has
	393	* just returned nonzero. It is allowed to block, e.g. for user memory
	394	* access. The arch can have machine-specific work to be done before
	395	* ptrace stops. On ia64, register backing store gets written back to user
	396	* memory here. Since this can be costly (requires dropping the siglock),
	397	* we only do it when the arch requires it for this particular stop, as
	398	* indicated by arch_ptrace_stop_needed().
	399	*/
	400	#define arch_ptrace_stop(code, info) do { } while (0)
	401	#endif
	402
bbc69863 RM	403	extern int task_current_syscall(struct task_struct target, long callno,
	404	unsigned long args[6], unsigned int maxargs,
	405	unsigned long sp, unsigned long pc);
	406
bf26c018 FW	407	#ifdef CONFIG_HAVE_HW_BREAKPOINT
	408	extern int ptrace_get_breakpoints(struct task_struct *tsk);
	409	extern void ptrace_put_breakpoints(struct task_struct *tsk);
	410	#else
	411	static inline void ptrace_put_breakpoints(struct task_struct *tsk) { }
	412	#endif /* CONFIG_HAVE_HW_BREAKPOINT */
	413
	414	#endif /* __KERNEL */
1da177e4 LT	415
1da177e4 LT	416	#endif