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1/*
2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
5
6#include "linux/audit.h"
7#include "linux/ptrace.h"
8#include "linux/sched.h"
9#include "asm/uaccess.h"
10#include "skas_ptrace.h"
11
12
13
14void user_enable_single_step(struct task_struct *child)
15{
16 child->ptrace |= PT_DTRACE;
17 child->thread.singlestep_syscall = 0;
18
19#ifdef SUBARCH_SET_SINGLESTEPPING
20 SUBARCH_SET_SINGLESTEPPING(child, 1);
21#endif
22}
23
24void user_disable_single_step(struct task_struct *child)
25{
26 child->ptrace &= ~PT_DTRACE;
27 child->thread.singlestep_syscall = 0;
28
29#ifdef SUBARCH_SET_SINGLESTEPPING
30 SUBARCH_SET_SINGLESTEPPING(child, 0);
31#endif
32}
33
34/*
35 * Called by kernel/ptrace.c when detaching..
36 */
37void ptrace_disable(struct task_struct *child)
38{
39 user_disable_single_step(child);
40}
41
42extern int peek_user(struct task_struct * child, long addr, long data);
43extern int poke_user(struct task_struct * child, long addr, long data);
44
45long arch_ptrace(struct task_struct *child, long request,
46 unsigned long addr, unsigned long data)
47{
48 int i, ret;
49 unsigned long __user *p = (void __user *)data;
50 void __user *vp = p;
51
52 switch (request) {
53 /* read the word at location addr in the USER area. */
54 case PTRACE_PEEKUSR:
55 ret = peek_user(child, addr, data);
56 break;
57
58 /* write the word at location addr in the USER area */
59 case PTRACE_POKEUSR:
60 ret = poke_user(child, addr, data);
61 break;
62
63 case PTRACE_SYSEMU:
64 case PTRACE_SYSEMU_SINGLESTEP:
65 ret = -EIO;
66 break;
67
68#ifdef PTRACE_GETREGS
69 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
70 if (!access_ok(VERIFY_WRITE, p, MAX_REG_OFFSET)) {
71 ret = -EIO;
72 break;
73 }
74 for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
75 __put_user(getreg(child, i), p);
76 p++;
77 }
78 ret = 0;
79 break;
80 }
81#endif
82#ifdef PTRACE_SETREGS
83 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
84 unsigned long tmp = 0;
85 if (!access_ok(VERIFY_READ, p, MAX_REG_OFFSET)) {
86 ret = -EIO;
87 break;
88 }
89 for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
90 __get_user(tmp, p);
91 putreg(child, i, tmp);
92 p++;
93 }
94 ret = 0;
95 break;
96 }
97#endif
98 case PTRACE_GET_THREAD_AREA:
99 ret = ptrace_get_thread_area(child, addr, vp);
100 break;
101
102 case PTRACE_SET_THREAD_AREA:
103 ret = ptrace_set_thread_area(child, addr, vp);
104 break;
105
106 case PTRACE_FAULTINFO: {
107 /*
108 * Take the info from thread->arch->faultinfo,
109 * but transfer max. sizeof(struct ptrace_faultinfo).
110 * On i386, ptrace_faultinfo is smaller!
111 */
112 ret = copy_to_user(p, &child->thread.arch.faultinfo,
113 sizeof(struct ptrace_faultinfo)) ?
114 -EIO : 0;
115 break;
116 }
117
118#ifdef PTRACE_LDT
119 case PTRACE_LDT: {
120 struct ptrace_ldt ldt;
121
122 if (copy_from_user(&ldt, p, sizeof(ldt))) {
123 ret = -EIO;
124 break;
125 }
126
127 /*
128 * This one is confusing, so just punt and return -EIO for
129 * now
130 */
131 ret = -EIO;
132 break;
133 }
134#endif
135 default:
136 ret = ptrace_request(child, request, addr, data);
137 if (ret == -EIO)
138 ret = subarch_ptrace(child, request, addr, data);
139 break;
140 }
141
142 return ret;
143}
144
145static void send_sigtrap(struct task_struct *tsk, struct uml_pt_regs *regs,
146 int error_code)
147{
148 struct siginfo info;
149
150 memset(&info, 0, sizeof(info));
151 info.si_signo = SIGTRAP;
152 info.si_code = TRAP_BRKPT;
153
154 /* User-mode eip? */
155 info.si_addr = UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL;
156
157 /* Send us the fake SIGTRAP */
158 force_sig_info(SIGTRAP, &info, tsk);
159}
160
161/*
162 * XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and
163 * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check
164 */
165void syscall_trace(struct uml_pt_regs *regs, int entryexit)
166{
167 int is_singlestep = (current->ptrace & PT_DTRACE) && entryexit;
168 int tracesysgood;
169
170 if (!entryexit)
171 audit_syscall_entry(HOST_AUDIT_ARCH,
172 UPT_SYSCALL_NR(regs),
173 UPT_SYSCALL_ARG1(regs),
174 UPT_SYSCALL_ARG2(regs),
175 UPT_SYSCALL_ARG3(regs),
176 UPT_SYSCALL_ARG4(regs));
177 else
178 audit_syscall_exit(regs);
179
180 /* Fake a debug trap */
181 if (is_singlestep)
182 send_sigtrap(current, regs, 0);
183
184 if (!test_thread_flag(TIF_SYSCALL_TRACE))
185 return;
186
187 if (!(current->ptrace & PT_PTRACED))
188 return;
189
190 /*
191 * the 0x80 provides a way for the tracing parent to distinguish
192 * between a syscall stop and SIGTRAP delivery
193 */
194 tracesysgood = (current->ptrace & PT_TRACESYSGOOD);
195 ptrace_notify(SIGTRAP | (tracesysgood ? 0x80 : 0));
196
197 if (entryexit) /* force do_signal() --> is_syscall() */
198 set_thread_flag(TIF_SIGPENDING);
199
200 /*
201 * this isn't the same as continuing with a signal, but it will do
202 * for normal use. strace only continues with a signal if the
203 * stopping signal is not SIGTRAP. -brl
204 */
205 if (current->exit_code) {
206 send_sig(current->exit_code, current, 1);
207 current->exit_code = 0;
208 }
209}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <linux/audit.h>
7#include <linux/ptrace.h>
8#include <linux/sched.h>
9#include <linux/uaccess.h>
10#include <asm/ptrace-abi.h>
11
12void user_enable_single_step(struct task_struct *child)
13{
14 set_tsk_thread_flag(child, TIF_SINGLESTEP);
15
16#ifdef SUBARCH_SET_SINGLESTEPPING
17 SUBARCH_SET_SINGLESTEPPING(child, 1);
18#endif
19}
20
21void user_disable_single_step(struct task_struct *child)
22{
23 clear_tsk_thread_flag(child, TIF_SINGLESTEP);
24
25#ifdef SUBARCH_SET_SINGLESTEPPING
26 SUBARCH_SET_SINGLESTEPPING(child, 0);
27#endif
28}
29
30/*
31 * Called by kernel/ptrace.c when detaching..
32 */
33void ptrace_disable(struct task_struct *child)
34{
35 user_disable_single_step(child);
36}
37
38long arch_ptrace(struct task_struct *child, long request,
39 unsigned long addr, unsigned long data)
40{
41 int i, ret;
42 unsigned long __user *p = (void __user *)data;
43 void __user *vp = p;
44
45 switch (request) {
46 /* read the word at location addr in the USER area. */
47 case PTRACE_PEEKUSR:
48 ret = peek_user(child, addr, data);
49 break;
50
51 /* write the word at location addr in the USER area */
52 case PTRACE_POKEUSR:
53 ret = poke_user(child, addr, data);
54 break;
55
56 case PTRACE_SYSEMU:
57 case PTRACE_SYSEMU_SINGLESTEP:
58 ret = -EIO;
59 break;
60
61#ifdef PTRACE_GETREGS
62 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
63 if (!access_ok(p, MAX_REG_OFFSET)) {
64 ret = -EIO;
65 break;
66 }
67 for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
68 __put_user(getreg(child, i), p);
69 p++;
70 }
71 ret = 0;
72 break;
73 }
74#endif
75#ifdef PTRACE_SETREGS
76 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
77 unsigned long tmp = 0;
78 if (!access_ok(p, MAX_REG_OFFSET)) {
79 ret = -EIO;
80 break;
81 }
82 for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
83 __get_user(tmp, p);
84 putreg(child, i, tmp);
85 p++;
86 }
87 ret = 0;
88 break;
89 }
90#endif
91 case PTRACE_GET_THREAD_AREA:
92 ret = ptrace_get_thread_area(child, addr, vp);
93 break;
94
95 case PTRACE_SET_THREAD_AREA:
96 ret = ptrace_set_thread_area(child, addr, vp);
97 break;
98
99 default:
100 ret = ptrace_request(child, request, addr, data);
101 if (ret == -EIO)
102 ret = subarch_ptrace(child, request, addr, data);
103 break;
104 }
105
106 return ret;
107}
108
109static void send_sigtrap(struct uml_pt_regs *regs, int error_code)
110{
111 /* Send us the fake SIGTRAP */
112 force_sig_fault(SIGTRAP, TRAP_BRKPT,
113 /* User-mode eip? */
114 UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL);
115}
116
117/*
118 * XXX Check TIF_SINGLESTEP for singlestepping check and
119 * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check
120 */
121int syscall_trace_enter(struct pt_regs *regs)
122{
123 audit_syscall_entry(UPT_SYSCALL_NR(®s->regs),
124 UPT_SYSCALL_ARG1(®s->regs),
125 UPT_SYSCALL_ARG2(®s->regs),
126 UPT_SYSCALL_ARG3(®s->regs),
127 UPT_SYSCALL_ARG4(®s->regs));
128
129 if (!test_thread_flag(TIF_SYSCALL_TRACE))
130 return 0;
131
132 return ptrace_report_syscall_entry(regs);
133}
134
135void syscall_trace_leave(struct pt_regs *regs)
136{
137 int ptraced = current->ptrace;
138
139 audit_syscall_exit(regs);
140
141 /* Fake a debug trap */
142 if (test_thread_flag(TIF_SINGLESTEP))
143 send_sigtrap(®s->regs, 0);
144
145 if (!test_thread_flag(TIF_SYSCALL_TRACE))
146 return;
147
148 ptrace_report_syscall_exit(regs, 0);
149 /* force do_signal() --> is_syscall() */
150 if (ptraced & PT_PTRACED)
151 set_thread_flag(TIF_SIGPENDING);
152}