aboutsummaryrefslogtreecommitdiffstats
path: root/arch/parisc/kernel/ptrace.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/parisc/kernel/ptrace.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/parisc/kernel/ptrace.c')
-rw-r--r--arch/parisc/kernel/ptrace.c423
1 files changed, 423 insertions, 0 deletions
diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c
new file mode 100644
index 000000000000..2937a9236384
--- /dev/null
+++ b/arch/parisc/kernel/ptrace.c
@@ -0,0 +1,423 @@
1/*
2 * Kernel support for the ptrace() and syscall tracing interfaces.
3 *
4 * Copyright (C) 2000 Hewlett-Packard Co, Linuxcare Inc.
5 * Copyright (C) 2000 Matthew Wilcox <matthew@wil.cx>
6 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
7 */
8
9#include <linux/kernel.h>
10#include <linux/sched.h>
11#include <linux/mm.h>
12#include <linux/smp.h>
13#include <linux/smp_lock.h>
14#include <linux/errno.h>
15#include <linux/ptrace.h>
16#include <linux/user.h>
17#include <linux/personality.h>
18#include <linux/security.h>
19#include <linux/compat.h>
20
21#include <asm/uaccess.h>
22#include <asm/pgtable.h>
23#include <asm/system.h>
24#include <asm/processor.h>
25#include <asm/offsets.h>
26
27/* PSW bits we allow the debugger to modify */
28#define USER_PSW_BITS (PSW_N | PSW_V | PSW_CB)
29
30#undef DEBUG_PTRACE
31
32#ifdef DEBUG_PTRACE
33#define DBG(x...) printk(x)
34#else
35#define DBG(x...)
36#endif
37
38#ifdef __LP64__
39
40/* This function is needed to translate 32 bit pt_regs offsets in to
41 * 64 bit pt_regs offsets. For example, a 32 bit gdb under a 64 bit kernel
42 * will request offset 12 if it wants gr3, but the lower 32 bits of
43 * the 64 bit kernels view of gr3 will be at offset 28 (3*8 + 4).
44 * This code relies on a 32 bit pt_regs being comprised of 32 bit values
45 * except for the fp registers which (a) are 64 bits, and (b) follow
46 * the gr registers at the start of pt_regs. The 32 bit pt_regs should
47 * be half the size of the 64 bit pt_regs, plus 32*4 to allow for fr[]
48 * being 64 bit in both cases.
49 */
50
51static long translate_usr_offset(long offset)
52{
53 if (offset < 0)
54 return -1;
55 else if (offset <= 32*4) /* gr[0..31] */
56 return offset * 2 + 4;
57 else if (offset <= 32*4+32*8) /* gr[0..31] + fr[0..31] */
58 return offset + 32*4;
59 else if (offset < sizeof(struct pt_regs)/2 + 32*4)
60 return offset * 2 + 4 - 32*8;
61 else
62 return -1;
63}
64#endif
65
66/*
67 * Called by kernel/ptrace.c when detaching..
68 *
69 * Make sure single step bits etc are not set.
70 */
71void ptrace_disable(struct task_struct *child)
72{
73 /* make sure the trap bits are not set */
74 pa_psw(child)->r = 0;
75 pa_psw(child)->t = 0;
76 pa_psw(child)->h = 0;
77 pa_psw(child)->l = 0;
78}
79
80long sys_ptrace(long request, pid_t pid, long addr, long data)
81{
82 struct task_struct *child;
83 long ret;
84#ifdef DEBUG_PTRACE
85 long oaddr=addr, odata=data;
86#endif
87
88 lock_kernel();
89 ret = -EPERM;
90 if (request == PTRACE_TRACEME) {
91 /* are we already being traced? */
92 if (current->ptrace & PT_PTRACED)
93 goto out;
94
95 ret = security_ptrace(current->parent, current);
96 if (ret)
97 goto out;
98
99 /* set the ptrace bit in the process flags. */
100 current->ptrace |= PT_PTRACED;
101 ret = 0;
102 goto out;
103 }
104
105 ret = -ESRCH;
106 read_lock(&tasklist_lock);
107 child = find_task_by_pid(pid);
108 if (child)
109 get_task_struct(child);
110 read_unlock(&tasklist_lock);
111 if (!child)
112 goto out;
113 ret = -EPERM;
114 if (pid == 1) /* no messing around with init! */
115 goto out_tsk;
116
117 if (request == PTRACE_ATTACH) {
118 ret = ptrace_attach(child);
119 goto out_tsk;
120 }
121
122 ret = ptrace_check_attach(child, request == PTRACE_KILL);
123 if (ret < 0)
124 goto out_tsk;
125
126 switch (request) {
127 case PTRACE_PEEKTEXT: /* read word at location addr. */
128 case PTRACE_PEEKDATA: {
129 int copied;
130
131#ifdef __LP64__
132 if (is_compat_task(child)) {
133 unsigned int tmp;
134
135 addr &= 0xffffffffL;
136 copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
137 ret = -EIO;
138 if (copied != sizeof(tmp))
139 goto out_tsk;
140 ret = put_user(tmp,(unsigned int *) data);
141 DBG("sys_ptrace(PEEK%s, %d, %lx, %lx) returning %ld, data %x\n",
142 request == PTRACE_PEEKTEXT ? "TEXT" : "DATA",
143 pid, oaddr, odata, ret, tmp);
144 }
145 else
146#endif
147 {
148 unsigned long tmp;
149
150 copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
151 ret = -EIO;
152 if (copied != sizeof(tmp))
153 goto out_tsk;
154 ret = put_user(tmp,(unsigned long *) data);
155 }
156 goto out_tsk;
157 }
158
159 /* when I and D space are separate, this will have to be fixed. */
160 case PTRACE_POKETEXT: /* write the word at location addr. */
161 case PTRACE_POKEDATA:
162 ret = 0;
163#ifdef __LP64__
164 if (is_compat_task(child)) {
165 unsigned int tmp = (unsigned int)data;
166 DBG("sys_ptrace(POKE%s, %d, %lx, %lx)\n",
167 request == PTRACE_POKETEXT ? "TEXT" : "DATA",
168 pid, oaddr, odata);
169 addr &= 0xffffffffL;
170 if (access_process_vm(child, addr, &tmp, sizeof(tmp), 1) == sizeof(tmp))
171 goto out_tsk;
172 }
173 else
174#endif
175 {
176 if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
177 goto out_tsk;
178 }
179 ret = -EIO;
180 goto out_tsk;
181
182 /* Read the word at location addr in the USER area. For ptraced
183 processes, the kernel saves all regs on a syscall. */
184 case PTRACE_PEEKUSR: {
185 ret = -EIO;
186#ifdef __LP64__
187 if (is_compat_task(child)) {
188 unsigned int tmp;
189
190 if (addr & (sizeof(int)-1))
191 goto out_tsk;
192 if ((addr = translate_usr_offset(addr)) < 0)
193 goto out_tsk;
194
195 tmp = *(unsigned int *) ((char *) task_regs(child) + addr);
196 ret = put_user(tmp, (unsigned int *) data);
197 DBG("sys_ptrace(PEEKUSR, %d, %lx, %lx) returning %ld, addr %lx, data %x\n",
198 pid, oaddr, odata, ret, addr, tmp);
199 }
200 else
201#endif
202 {
203 unsigned long tmp;
204
205 if ((addr & (sizeof(long)-1)) || (unsigned long) addr >= sizeof(struct pt_regs))
206 goto out_tsk;
207 tmp = *(unsigned long *) ((char *) task_regs(child) + addr);
208 ret = put_user(tmp, (unsigned long *) data);
209 }
210 goto out_tsk;
211 }
212
213 /* Write the word at location addr in the USER area. This will need
214 to change when the kernel no longer saves all regs on a syscall.
215 FIXME. There is a problem at the moment in that r3-r18 are only
216 saved if the process is ptraced on syscall entry, and even then
217 those values are overwritten by actual register values on syscall
218 exit. */
219 case PTRACE_POKEUSR:
220 ret = -EIO;
221 /* Some register values written here may be ignored in
222 * entry.S:syscall_restore_rfi; e.g. iaoq is written with
223 * r31/r31+4, and not with the values in pt_regs.
224 */
225 /* PT_PSW=0, so this is valid for 32 bit processes under 64
226 * bit kernels.
227 */
228 if (addr == PT_PSW) {
229 /* PT_PSW=0, so this is valid for 32 bit processes
230 * under 64 bit kernels.
231 *
232 * Allow writing to Nullify, Divide-step-correction,
233 * and carry/borrow bits.
234 * BEWARE, if you set N, and then single step, it won't
235 * stop on the nullified instruction.
236 */
237 DBG("sys_ptrace(POKEUSR, %d, %lx, %lx)\n",
238 pid, oaddr, odata);
239 data &= USER_PSW_BITS;
240 task_regs(child)->gr[0] &= ~USER_PSW_BITS;
241 task_regs(child)->gr[0] |= data;
242 ret = 0;
243 goto out_tsk;
244 }
245#ifdef __LP64__
246 if (is_compat_task(child)) {
247 if (addr & (sizeof(int)-1))
248 goto out_tsk;
249 if ((addr = translate_usr_offset(addr)) < 0)
250 goto out_tsk;
251 DBG("sys_ptrace(POKEUSR, %d, %lx, %lx) addr %lx\n",
252 pid, oaddr, odata, addr);
253 if (addr >= PT_FR0 && addr <= PT_FR31 + 4) {
254 /* Special case, fp regs are 64 bits anyway */
255 *(unsigned int *) ((char *) task_regs(child) + addr) = data;
256 ret = 0;
257 }
258 else if ((addr >= PT_GR1+4 && addr <= PT_GR31+4) ||
259 addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4 ||
260 addr == PT_SAR+4) {
261 /* Zero the top 32 bits */
262 *(unsigned int *) ((char *) task_regs(child) + addr - 4) = 0;
263 *(unsigned int *) ((char *) task_regs(child) + addr) = data;
264 ret = 0;
265 }
266 goto out_tsk;
267 }
268 else
269#endif
270 {
271 if ((addr & (sizeof(long)-1)) || (unsigned long) addr >= sizeof(struct pt_regs))
272 goto out_tsk;
273 if ((addr >= PT_GR1 && addr <= PT_GR31) ||
274 addr == PT_IAOQ0 || addr == PT_IAOQ1 ||
275 (addr >= PT_FR0 && addr <= PT_FR31 + 4) ||
276 addr == PT_SAR) {
277 *(unsigned long *) ((char *) task_regs(child) + addr) = data;
278 ret = 0;
279 }
280 goto out_tsk;
281 }
282
283 case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
284 case PTRACE_CONT:
285 ret = -EIO;
286 DBG("sys_ptrace(%s)\n",
287 request == PTRACE_SYSCALL ? "SYSCALL" : "CONT");
288 if ((unsigned long) data > _NSIG)
289 goto out_tsk;
290 child->ptrace &= ~(PT_SINGLESTEP|PT_BLOCKSTEP);
291 if (request == PTRACE_SYSCALL) {
292 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
293 } else {
294 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
295 }
296 child->exit_code = data;
297 goto out_wake_notrap;
298
299 case PTRACE_KILL:
300 /*
301 * make the child exit. Best I can do is send it a
302 * sigkill. perhaps it should be put in the status
303 * that it wants to exit.
304 */
305 DBG("sys_ptrace(KILL)\n");
306 if (child->exit_state == EXIT_ZOMBIE) /* already dead */
307 goto out_tsk;
308 child->exit_code = SIGKILL;
309 goto out_wake_notrap;
310
311 case PTRACE_SINGLEBLOCK:
312 DBG("sys_ptrace(SINGLEBLOCK)\n");
313 ret = -EIO;
314 if ((unsigned long) data > _NSIG)
315 goto out_tsk;
316 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
317 child->ptrace &= ~PT_SINGLESTEP;
318 child->ptrace |= PT_BLOCKSTEP;
319 child->exit_code = data;
320
321 /* Enable taken branch trap. */
322 pa_psw(child)->r = 0;
323 pa_psw(child)->t = 1;
324 pa_psw(child)->h = 0;
325 pa_psw(child)->l = 0;
326 goto out_wake;
327
328 case PTRACE_SINGLESTEP:
329 DBG("sys_ptrace(SINGLESTEP)\n");
330 ret = -EIO;
331 if ((unsigned long) data > _NSIG)
332 goto out_tsk;
333
334 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
335 child->ptrace &= ~PT_BLOCKSTEP;
336 child->ptrace |= PT_SINGLESTEP;
337 child->exit_code = data;
338
339 if (pa_psw(child)->n) {
340 struct siginfo si;
341
342 /* Nullified, just crank over the queue. */
343 task_regs(child)->iaoq[0] = task_regs(child)->iaoq[1];
344 task_regs(child)->iasq[0] = task_regs(child)->iasq[1];
345 task_regs(child)->iaoq[1] = task_regs(child)->iaoq[0] + 4;
346 pa_psw(child)->n = 0;
347 pa_psw(child)->x = 0;
348 pa_psw(child)->y = 0;
349 pa_psw(child)->z = 0;
350 pa_psw(child)->b = 0;
351 ptrace_disable(child);
352 /* Don't wake up the child, but let the
353 parent know something happened. */
354 si.si_code = TRAP_TRACE;
355 si.si_addr = (void __user *) (task_regs(child)->iaoq[0] & ~3);
356 si.si_signo = SIGTRAP;
357 si.si_errno = 0;
358 force_sig_info(SIGTRAP, &si, child);
359 //notify_parent(child, SIGCHLD);
360 //ret = 0;
361 goto out_wake;
362 }
363
364 /* Enable recovery counter traps. The recovery counter
365 * itself will be set to zero on a task switch. If the
366 * task is suspended on a syscall then the syscall return
367 * path will overwrite the recovery counter with a suitable
368 * value such that it traps once back in user space. We
369 * disable interrupts in the childs PSW here also, to avoid
370 * interrupts while the recovery counter is decrementing.
371 */
372 pa_psw(child)->r = 1;
373 pa_psw(child)->t = 0;
374 pa_psw(child)->h = 0;
375 pa_psw(child)->l = 0;
376 /* give it a chance to run. */
377 goto out_wake;
378
379 case PTRACE_DETACH:
380 ret = ptrace_detach(child, data);
381 goto out_tsk;
382
383 case PTRACE_GETEVENTMSG:
384 ret = put_user(child->ptrace_message, (unsigned int __user *) data);
385 goto out_tsk;
386
387 default:
388 ret = ptrace_request(child, request, addr, data);
389 goto out_tsk;
390 }
391
392out_wake_notrap:
393 ptrace_disable(child);
394out_wake:
395 wake_up_process(child);
396 ret = 0;
397out_tsk:
398 put_task_struct(child);
399out:
400 unlock_kernel();
401 DBG("sys_ptrace(%ld, %d, %lx, %lx) returning %ld\n",
402 request, pid, oaddr, odata, ret);
403 return ret;
404}
405
406void syscall_trace(void)
407{
408 if (!test_thread_flag(TIF_SYSCALL_TRACE))
409 return;
410 if (!(current->ptrace & PT_PTRACED))
411 return;
412 ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
413 ? 0x80 : 0));
414 /*
415 * this isn't the same as continuing with a signal, but it will do
416 * for normal use. strace only continues with a signal if the
417 * stopping signal is not SIGTRAP. -brl
418 */
419 if (current->exit_code) {
420 send_sig(current->exit_code, current, 1);
421 current->exit_code = 0;
422 }
423}
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-28 03:09:59 -0500