xref: /linux-6.15/include/linux/ptrace.h (revision a1e58bbd)
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 
19 #define PTRACE_ATTACH		  16
20 #define PTRACE_DETACH		  17
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 
30 /* options set using PTRACE_SETOPTIONS */
31 #define PTRACE_O_TRACESYSGOOD	0x00000001
32 #define PTRACE_O_TRACEFORK	0x00000002
33 #define PTRACE_O_TRACEVFORK	0x00000004
34 #define PTRACE_O_TRACECLONE	0x00000008
35 #define PTRACE_O_TRACEEXEC	0x00000010
36 #define PTRACE_O_TRACEVFORKDONE	0x00000020
37 #define PTRACE_O_TRACEEXIT	0x00000040
38 
39 #define PTRACE_O_MASK		0x0000007f
40 
41 /* Wait extended result codes for the above trace options.  */
42 #define PTRACE_EVENT_FORK	1
43 #define PTRACE_EVENT_VFORK	2
44 #define PTRACE_EVENT_CLONE	3
45 #define PTRACE_EVENT_EXEC	4
46 #define PTRACE_EVENT_VFORK_DONE	5
47 #define PTRACE_EVENT_EXIT	6
48 
49 #include <asm/ptrace.h>
50 
51 #ifdef __KERNEL__
52 /*
53  * Ptrace flags
54  *
55  * The owner ship rules for task->ptrace which holds the ptrace
56  * flags is simple.  When a task is running it owns it's task->ptrace
57  * flags.  When the a task is stopped the ptracer owns task->ptrace.
58  */
59 
60 #define PT_PTRACED	0x00000001
61 #define PT_DTRACE	0x00000002	/* delayed trace (used on m68k, i386) */
62 #define PT_TRACESYSGOOD	0x00000004
63 #define PT_PTRACE_CAP	0x00000008	/* ptracer can follow suid-exec */
64 #define PT_TRACE_FORK	0x00000010
65 #define PT_TRACE_VFORK	0x00000020
66 #define PT_TRACE_CLONE	0x00000040
67 #define PT_TRACE_EXEC	0x00000080
68 #define PT_TRACE_VFORK_DONE	0x00000100
69 #define PT_TRACE_EXIT	0x00000200
70 
71 #define PT_TRACE_MASK	0x000003f4
72 
73 /* single stepping state bits (used on ARM and PA-RISC) */
74 #define PT_SINGLESTEP_BIT	31
75 #define PT_SINGLESTEP		(1<<PT_SINGLESTEP_BIT)
76 #define PT_BLOCKSTEP_BIT	30
77 #define PT_BLOCKSTEP		(1<<PT_BLOCKSTEP_BIT)
78 
79 #include <linux/compiler.h>		/* For unlikely.  */
80 #include <linux/sched.h>		/* For struct task_struct.  */
81 
82 
83 extern long arch_ptrace(struct task_struct *child, long request, long addr, long data);
84 extern struct task_struct *ptrace_get_task_struct(pid_t pid);
85 extern int ptrace_traceme(void);
86 extern int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len);
87 extern int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len);
88 extern int ptrace_attach(struct task_struct *tsk);
89 extern int ptrace_detach(struct task_struct *, unsigned int);
90 extern void ptrace_disable(struct task_struct *);
91 extern int ptrace_check_attach(struct task_struct *task, int kill);
92 extern int ptrace_request(struct task_struct *child, long request, long addr, long data);
93 extern void ptrace_notify(int exit_code);
94 extern void __ptrace_link(struct task_struct *child,
95 			  struct task_struct *new_parent);
96 extern void __ptrace_unlink(struct task_struct *child);
97 extern void ptrace_untrace(struct task_struct *child);
98 extern int ptrace_may_attach(struct task_struct *task);
99 extern int __ptrace_may_attach(struct task_struct *task);
100 
101 static inline void ptrace_link(struct task_struct *child,
102 			       struct task_struct *new_parent)
103 {
104 	if (unlikely(child->ptrace))
105 		__ptrace_link(child, new_parent);
106 }
107 static inline void ptrace_unlink(struct task_struct *child)
108 {
109 	if (unlikely(child->ptrace))
110 		__ptrace_unlink(child);
111 }
112 
113 int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data);
114 int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data);
115 
116 #ifndef force_successful_syscall_return
117 /*
118  * System call handlers that, upon successful completion, need to return a
119  * negative value should call force_successful_syscall_return() right before
120  * returning.  On architectures where the syscall convention provides for a
121  * separate error flag (e.g., alpha, ia64, ppc{,64}, sparc{,64}, possibly
122  * others), this macro can be used to ensure that the error flag will not get
123  * set.  On architectures which do not support a separate error flag, the macro
124  * is a no-op and the spurious error condition needs to be filtered out by some
125  * other means (e.g., in user-level, by passing an extra argument to the
126  * syscall handler, or something along those lines).
127  */
128 #define force_successful_syscall_return() do { } while (0)
129 #endif
130 
131 /*
132  * <asm/ptrace.h> should define the following things inside #ifdef __KERNEL__.
133  *
134  * These do-nothing inlines are used when the arch does not
135  * implement single-step.  The kerneldoc comments are here
136  * to document the interface for all arch definitions.
137  */
138 
139 #ifndef arch_has_single_step
140 /**
141  * arch_has_single_step - does this CPU support user-mode single-step?
142  *
143  * If this is defined, then there must be function declarations or
144  * inlines for user_enable_single_step() and user_disable_single_step().
145  * arch_has_single_step() should evaluate to nonzero iff the machine
146  * supports instruction single-step for user mode.
147  * It can be a constant or it can test a CPU feature bit.
148  */
149 #define arch_has_single_step()		(0)
150 
151 /**
152  * user_enable_single_step - single-step in user-mode task
153  * @task: either current or a task stopped in %TASK_TRACED
154  *
155  * This can only be called when arch_has_single_step() has returned nonzero.
156  * Set @task so that when it returns to user mode, it will trap after the
157  * next single instruction executes.  If arch_has_block_step() is defined,
158  * this must clear the effects of user_enable_block_step() too.
159  */
160 static inline void user_enable_single_step(struct task_struct *task)
161 {
162 	BUG();			/* This can never be called.  */
163 }
164 
165 /**
166  * user_disable_single_step - cancel user-mode single-step
167  * @task: either current or a task stopped in %TASK_TRACED
168  *
169  * Clear @task of the effects of user_enable_single_step() and
170  * user_enable_block_step().  This can be called whether or not either
171  * of those was ever called on @task, and even if arch_has_single_step()
172  * returned zero.
173  */
174 static inline void user_disable_single_step(struct task_struct *task)
175 {
176 }
177 #endif	/* arch_has_single_step */
178 
179 #ifndef arch_has_block_step
180 /**
181  * arch_has_block_step - does this CPU support user-mode block-step?
182  *
183  * If this is defined, then there must be a function declaration or inline
184  * for user_enable_block_step(), and arch_has_single_step() must be defined
185  * too.  arch_has_block_step() should evaluate to nonzero iff the machine
186  * supports step-until-branch for user mode.  It can be a constant or it
187  * can test a CPU feature bit.
188  */
189 #define arch_has_block_step()		(0)
190 
191 /**
192  * user_enable_block_step - step until branch in user-mode task
193  * @task: either current or a task stopped in %TASK_TRACED
194  *
195  * This can only be called when arch_has_block_step() has returned nonzero,
196  * and will never be called when single-instruction stepping is being used.
197  * Set @task so that when it returns to user mode, it will trap after the
198  * next branch or trap taken.
199  */
200 static inline void user_enable_block_step(struct task_struct *task)
201 {
202 	BUG();			/* This can never be called.  */
203 }
204 #endif	/* arch_has_block_step */
205 
206 #ifndef arch_ptrace_stop_needed
207 /**
208  * arch_ptrace_stop_needed - Decide whether arch_ptrace_stop() should be called
209  * @code:	current->exit_code value ptrace will stop with
210  * @info:	siginfo_t pointer (or %NULL) for signal ptrace will stop with
211  *
212  * This is called with the siglock held, to decide whether or not it's
213  * necessary to release the siglock and call arch_ptrace_stop() with the
214  * same @code and @info arguments.  It can be defined to a constant if
215  * arch_ptrace_stop() is never required, or always is.  On machines where
216  * this makes sense, it should be defined to a quick test to optimize out
217  * calling arch_ptrace_stop() when it would be superfluous.  For example,
218  * if the thread has not been back to user mode since the last stop, the
219  * thread state might indicate that nothing needs to be done.
220  */
221 #define arch_ptrace_stop_needed(code, info)	(0)
222 #endif
223 
224 #ifndef arch_ptrace_stop
225 /**
226  * arch_ptrace_stop - Do machine-specific work before stopping for ptrace
227  * @code:	current->exit_code value ptrace will stop with
228  * @info:	siginfo_t pointer (or %NULL) for signal ptrace will stop with
229  *
230  * This is called with no locks held when arch_ptrace_stop_needed() has
231  * just returned nonzero.  It is allowed to block, e.g. for user memory
232  * access.  The arch can have machine-specific work to be done before
233  * ptrace stops.  On ia64, register backing store gets written back to user
234  * memory here.  Since this can be costly (requires dropping the siglock),
235  * we only do it when the arch requires it for this particular stop, as
236  * indicated by arch_ptrace_stop_needed().
237  */
238 #define arch_ptrace_stop(code, info)		do { } while (0)
239 #endif
240 
241 #endif
242 
243 #endif
244