1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
|
/*
* `ptrace' system call
*
* Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2007-2009 PetaLogix
* Copyright (C) 2004-2007 John Williams <john.williams@petalogix.com>
*
* derived from arch/v850/kernel/ptrace.c
*
* Copyright (C) 2002,03 NEC Electronics Corporation
* Copyright (C) 2002,03 Miles Bader <miles@gnu.org>
*
* Derived from arch/mips/kernel/ptrace.c:
*
* Copyright (C) 1992 Ross Biro
* Copyright (C) Linus Torvalds
* Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
* Copyright (C) 1996 David S. Miller
* Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
* Copyright (C) 1999 MIPS Technologies, Inc.
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file COPYING in the main directory of this
* archive for more details.
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/signal.h>
#include <linux/elf.h>
#include <linux/audit.h>
#include <linux/seccomp.h>
#include <linux/tracehook.h>
#include <linux/errno.h>
#include <asm/processor.h>
#include <linux/uaccess.h>
#include <asm/asm-offsets.h>
/* Returns the address where the register at REG_OFFS in P is stashed away. */
static microblaze_reg_t *reg_save_addr(unsigned reg_offs,
struct task_struct *t)
{
struct pt_regs *regs;
/*
* Three basic cases:
*
* (1) A register normally saved before calling the scheduler, is
* available in the kernel entry pt_regs structure at the top
* of the kernel stack. The kernel trap/irq exit path takes
* care to save/restore almost all registers for ptrace'd
* processes.
*
* (2) A call-clobbered register, where the process P entered the
* kernel via [syscall] trap, is not stored anywhere; that's
* OK, because such registers are not expected to be preserved
* when the trap returns anyway (so we don't actually bother to
* test for this case).
*
* (3) A few registers not used at all by the kernel, and so
* normally never saved except by context-switches, are in the
* context switch state.
*/
/* Register saved during kernel entry (or not available). */
regs = task_pt_regs(t);
return (microblaze_reg_t *)((char *)regs + reg_offs);
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
int rval;
unsigned long val = 0;
unsigned long copied;
switch (request) {
/* Read/write the word at location ADDR in the registers. */
case PTRACE_PEEKUSR:
case PTRACE_POKEUSR:
pr_debug("PEEKUSR/POKEUSR : 0x%08lx\n", addr);
rval = 0;
if (addr >= PT_SIZE && request == PTRACE_PEEKUSR) {
/*
* Special requests that don't actually correspond
* to offsets in struct pt_regs.
*/
if (addr == PT_TEXT_ADDR) {
val = child->mm->start_code;
} else if (addr == PT_DATA_ADDR) {
val = child->mm->start_data;
} else if (addr == PT_TEXT_LEN) {
val = child->mm->end_code
- child->mm->start_code;
} else {
rval = -EIO;
}
} else if (addr >= 0 && addr < PT_SIZE && (addr & 0x3) == 0) {
microblaze_reg_t *reg_addr = reg_save_addr(addr, child);
if (request == PTRACE_PEEKUSR)
val = *reg_addr;
else
*reg_addr = data;
} else
rval = -EIO;
if (rval == 0 && request == PTRACE_PEEKUSR)
rval = put_user(val, (unsigned long *)data);
break;
/* Continue and stop at next (return from) syscall */
case PTRACE_SYSCALL:
pr_debug("PTRACE_SYSCALL\n");
case PTRACE_SINGLESTEP:
pr_debug("PTRACE_SINGLESTEP\n");
/* Restart after a signal. */
case PTRACE_CONT:
pr_debug("PTRACE_CONT\n");
rval = -EIO;
if (!valid_signal(data))
break;
if (request == PTRACE_SYSCALL)
set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
else
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
child->exit_code = data;
pr_debug("wakeup_process\n");
wake_up_process(child);
rval = 0;
break;
/*
* make the child exit. Best I can do is send it a sigkill.
* perhaps it should be put in the status that it wants to
* exit.
*/
case PTRACE_KILL:
pr_debug("PTRACE_KILL\n");
rval = 0;
if (child->exit_state == EXIT_ZOMBIE) /* already dead */
break;
child->exit_code = SIGKILL;
wake_up_process(child);
break;
default:
rval = ptrace_request(child, request, addr, data);
}
return rval;
}
asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
{
long ret = 0;
secure_computing(regs->r12);
if (test_thread_flag(TIF_SYSCALL_TRACE) &&
tracehook_report_syscall_entry(regs))
/*
* Tracing decided this syscall should not happen.
* We'll return a bogus call number to get an ENOSYS
* error, but leave the original number in regs->regs[0].
*/
ret = -1L;
if (unlikely(current->audit_context))
audit_syscall_entry(EM_XILINX_MICROBLAZE, regs->r12,
regs->r5, regs->r6,
regs->r7, regs->r8);
return ret ?: regs->r12;
}
asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
{
int step;
if (unlikely(current->audit_context))
audit_syscall_exit(AUDITSC_RESULT(regs->r3), regs->r3);
step = test_thread_flag(TIF_SINGLESTEP);
if (step || test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall_exit(regs, step);
}
#if 0
static asmlinkage void syscall_trace(void)
{
if (!test_thread_flag(TIF_SYSCALL_TRACE))
return;
if (!(current->ptrace & PT_PTRACED))
return;
/* The 0x80 provides a way for the tracing parent to distinguish
between a syscall stop and SIGTRAP delivery */
ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
? 0x80 : 0));
/*
* this isn't the same as continuing with a signal, but it will do
* for normal use. strace only continues with a signal if the
* stopping signal is not SIGTRAP. -brl
*/
if (current->exit_code) {
send_sig(current->exit_code, current, 1);
current->exit_code = 0;
}
}
#endif
void ptrace_disable(struct task_struct *child)
{
/* nothing to do */
}
|
