Loading...
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/*
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 <linux/tracehook.h>
10#include <asm/uaccess.h>
11#include <skas_ptrace.h>
12
13
14
15void user_enable_single_step(struct task_struct *child)
16{
17 child->ptrace |= PT_DTRACE;
18 child->thread.singlestep_syscall = 0;
19
20#ifdef SUBARCH_SET_SINGLESTEPPING
21 SUBARCH_SET_SINGLESTEPPING(child, 1);
22#endif
23}
24
25void user_disable_single_step(struct task_struct *child)
26{
27 child->ptrace &= ~PT_DTRACE;
28 child->thread.singlestep_syscall = 0;
29
30#ifdef SUBARCH_SET_SINGLESTEPPING
31 SUBARCH_SET_SINGLESTEPPING(child, 0);
32#endif
33}
34
35/*
36 * Called by kernel/ptrace.c when detaching..
37 */
38void ptrace_disable(struct task_struct *child)
39{
40 user_disable_single_step(child);
41}
42
43extern int peek_user(struct task_struct * child, long addr, long data);
44extern int poke_user(struct task_struct * child, long addr, long data);
45
46long arch_ptrace(struct task_struct *child, long request,
47 unsigned long addr, unsigned long data)
48{
49 int i, ret;
50 unsigned long __user *p = (void __user *)data;
51 void __user *vp = p;
52
53 switch (request) {
54 /* read the word at location addr in the USER area. */
55 case PTRACE_PEEKUSR:
56 ret = peek_user(child, addr, data);
57 break;
58
59 /* write the word at location addr in the USER area */
60 case PTRACE_POKEUSR:
61 ret = poke_user(child, addr, data);
62 break;
63
64 case PTRACE_SYSEMU:
65 case PTRACE_SYSEMU_SINGLESTEP:
66 ret = -EIO;
67 break;
68
69#ifdef PTRACE_GETREGS
70 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
71 if (!access_ok(VERIFY_WRITE, p, MAX_REG_OFFSET)) {
72 ret = -EIO;
73 break;
74 }
75 for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
76 __put_user(getreg(child, i), p);
77 p++;
78 }
79 ret = 0;
80 break;
81 }
82#endif
83#ifdef PTRACE_SETREGS
84 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
85 unsigned long tmp = 0;
86 if (!access_ok(VERIFY_READ, p, MAX_REG_OFFSET)) {
87 ret = -EIO;
88 break;
89 }
90 for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
91 __get_user(tmp, p);
92 putreg(child, i, tmp);
93 p++;
94 }
95 ret = 0;
96 break;
97 }
98#endif
99 case PTRACE_GET_THREAD_AREA:
100 ret = ptrace_get_thread_area(child, addr, vp);
101 break;
102
103 case PTRACE_SET_THREAD_AREA:
104 ret = ptrace_set_thread_area(child, addr, vp);
105 break;
106
107 case PTRACE_FAULTINFO: {
108 /*
109 * Take the info from thread->arch->faultinfo,
110 * but transfer max. sizeof(struct ptrace_faultinfo).
111 * On i386, ptrace_faultinfo is smaller!
112 */
113 ret = copy_to_user(p, &child->thread.arch.faultinfo,
114 sizeof(struct ptrace_faultinfo)) ?
115 -EIO : 0;
116 break;
117 }
118
119#ifdef PTRACE_LDT
120 case PTRACE_LDT: {
121 struct ptrace_ldt ldt;
122
123 if (copy_from_user(&ldt, p, sizeof(ldt))) {
124 ret = -EIO;
125 break;
126 }
127
128 /*
129 * This one is confusing, so just punt and return -EIO for
130 * now
131 */
132 ret = -EIO;
133 break;
134 }
135#endif
136 default:
137 ret = ptrace_request(child, request, addr, data);
138 if (ret == -EIO)
139 ret = subarch_ptrace(child, request, addr, data);
140 break;
141 }
142
143 return ret;
144}
145
146static void send_sigtrap(struct task_struct *tsk, struct uml_pt_regs *regs,
147 int error_code)
148{
149 struct siginfo info;
150
151 memset(&info, 0, sizeof(info));
152 info.si_signo = SIGTRAP;
153 info.si_code = TRAP_BRKPT;
154
155 /* User-mode eip? */
156 info.si_addr = UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL;
157
158 /* Send us the fake SIGTRAP */
159 force_sig_info(SIGTRAP, &info, tsk);
160}
161
162/*
163 * XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and
164 * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check
165 */
166void syscall_trace_enter(struct pt_regs *regs)
167{
168 audit_syscall_entry(HOST_AUDIT_ARCH,
169 UPT_SYSCALL_NR(®s->regs),
170 UPT_SYSCALL_ARG1(®s->regs),
171 UPT_SYSCALL_ARG2(®s->regs),
172 UPT_SYSCALL_ARG3(®s->regs),
173 UPT_SYSCALL_ARG4(®s->regs));
174
175 if (!test_thread_flag(TIF_SYSCALL_TRACE))
176 return;
177
178 tracehook_report_syscall_entry(regs);
179}
180
181void syscall_trace_leave(struct pt_regs *regs)
182{
183 int ptraced = current->ptrace;
184
185 audit_syscall_exit(regs);
186
187 /* Fake a debug trap */
188 if (ptraced & PT_DTRACE)
189 send_sigtrap(current, ®s->regs, 0);
190
191 if (!test_thread_flag(TIF_SYSCALL_TRACE))
192 return;
193
194 tracehook_report_syscall_exit(regs, 0);
195 /* force do_signal() --> is_syscall() */
196 if (ptraced & PT_PTRACED)
197 set_thread_flag(TIF_SIGPENDING);
198}