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15#include <linux/errno.h>
16#include <linux/hw_breakpoint.h>
17#include <linux/kernel.h>
18#include <linux/mm.h>
19#include <linux/perf_event.h>
20#include <linux/ptrace.h>
21#include <linux/sched.h>
22#include <linux/sched/task_stack.h>
23#include <linux/security.h>
24#include <linux/signal.h>
25#include <linux/smp.h>
26#include <linux/tracehook.h>
27#include <linux/uaccess.h>
28
29#include <asm/coprocessor.h>
30#include <asm/elf.h>
31#include <asm/page.h>
32#include <asm/pgtable.h>
33#include <asm/ptrace.h>
34
35
36void user_enable_single_step(struct task_struct *child)
37{
38 child->ptrace |= PT_SINGLESTEP;
39}
40
41void user_disable_single_step(struct task_struct *child)
42{
43 child->ptrace &= ~PT_SINGLESTEP;
44}
45
46
47
48
49
50void ptrace_disable(struct task_struct *child)
51{
52
53}
54
55static int ptrace_getregs(struct task_struct *child, void __user *uregs)
56{
57 struct pt_regs *regs = task_pt_regs(child);
58 xtensa_gregset_t __user *gregset = uregs;
59 unsigned long wb = regs->windowbase;
60 int i;
61
62 if (!access_ok(VERIFY_WRITE, uregs, sizeof(xtensa_gregset_t)))
63 return -EIO;
64
65 __put_user(regs->pc, &gregset->pc);
66 __put_user(regs->ps & ~(1 << PS_EXCM_BIT), &gregset->ps);
67 __put_user(regs->lbeg, &gregset->lbeg);
68 __put_user(regs->lend, &gregset->lend);
69 __put_user(regs->lcount, &gregset->lcount);
70 __put_user(regs->windowstart, &gregset->windowstart);
71 __put_user(regs->windowbase, &gregset->windowbase);
72 __put_user(regs->threadptr, &gregset->threadptr);
73
74 for (i = 0; i < XCHAL_NUM_AREGS; i++)
75 __put_user(regs->areg[i],
76 gregset->a + ((wb * 4 + i) % XCHAL_NUM_AREGS));
77
78 return 0;
79}
80
81static int ptrace_setregs(struct task_struct *child, void __user *uregs)
82{
83 struct pt_regs *regs = task_pt_regs(child);
84 xtensa_gregset_t *gregset = uregs;
85 const unsigned long ps_mask = PS_CALLINC_MASK | PS_OWB_MASK;
86 unsigned long ps;
87 unsigned long wb, ws;
88
89 if (!access_ok(VERIFY_WRITE, uregs, sizeof(xtensa_gregset_t)))
90 return -EIO;
91
92 __get_user(regs->pc, &gregset->pc);
93 __get_user(ps, &gregset->ps);
94 __get_user(regs->lbeg, &gregset->lbeg);
95 __get_user(regs->lend, &gregset->lend);
96 __get_user(regs->lcount, &gregset->lcount);
97 __get_user(ws, &gregset->windowstart);
98 __get_user(wb, &gregset->windowbase);
99 __get_user(regs->threadptr, &gregset->threadptr);
100
101 regs->ps = (regs->ps & ~ps_mask) | (ps & ps_mask) | (1 << PS_EXCM_BIT);
102
103 if (wb >= XCHAL_NUM_AREGS / 4)
104 return -EFAULT;
105
106 if (wb != regs->windowbase || ws != regs->windowstart) {
107 unsigned long rotws, wmask;
108
109 rotws = (((ws | (ws << WSBITS)) >> wb) &
110 ((1 << WSBITS) - 1)) & ~1;
111 wmask = ((rotws ? WSBITS + 1 - ffs(rotws) : 0) << 4) |
112 (rotws & 0xF) | 1;
113 regs->windowbase = wb;
114 regs->windowstart = ws;
115 regs->wmask = wmask;
116 }
117
118 if (wb != 0 && __copy_from_user(regs->areg + XCHAL_NUM_AREGS - wb * 4,
119 gregset->a, wb * 16))
120 return -EFAULT;
121
122 if (__copy_from_user(regs->areg, gregset->a + wb * 4,
123 (WSBITS - wb) * 16))
124 return -EFAULT;
125
126 return 0;
127}
128
129
130static int ptrace_getxregs(struct task_struct *child, void __user *uregs)
131{
132 struct pt_regs *regs = task_pt_regs(child);
133 struct thread_info *ti = task_thread_info(child);
134 elf_xtregs_t __user *xtregs = uregs;
135 int ret = 0;
136
137 if (!access_ok(VERIFY_WRITE, uregs, sizeof(elf_xtregs_t)))
138 return -EIO;
139
140#if XTENSA_HAVE_COPROCESSORS
141
142 coprocessor_flush_all(ti);
143 ret |= __copy_to_user(&xtregs->cp0, &ti->xtregs_cp,
144 sizeof(xtregs_coprocessor_t));
145#endif
146 ret |= __copy_to_user(&xtregs->opt, ®s->xtregs_opt,
147 sizeof(xtregs->opt));
148 ret |= __copy_to_user(&xtregs->user,&ti->xtregs_user,
149 sizeof(xtregs->user));
150
151 return ret ? -EFAULT : 0;
152}
153
154static int ptrace_setxregs(struct task_struct *child, void __user *uregs)
155{
156 struct thread_info *ti = task_thread_info(child);
157 struct pt_regs *regs = task_pt_regs(child);
158 elf_xtregs_t *xtregs = uregs;
159 int ret = 0;
160
161 if (!access_ok(VERIFY_READ, uregs, sizeof(elf_xtregs_t)))
162 return -EFAULT;
163
164#if XTENSA_HAVE_COPROCESSORS
165
166 coprocessor_flush_all(ti);
167 coprocessor_release_all(ti);
168
169 ret |= __copy_from_user(&ti->xtregs_cp, &xtregs->cp0,
170 sizeof(xtregs_coprocessor_t));
171#endif
172 ret |= __copy_from_user(®s->xtregs_opt, &xtregs->opt,
173 sizeof(xtregs->opt));
174 ret |= __copy_from_user(&ti->xtregs_user, &xtregs->user,
175 sizeof(xtregs->user));
176
177 return ret ? -EFAULT : 0;
178}
179
180static int ptrace_peekusr(struct task_struct *child, long regno,
181 long __user *ret)
182{
183 struct pt_regs *regs;
184 unsigned long tmp;
185
186 regs = task_pt_regs(child);
187 tmp = 0;
188
189 switch(regno) {
190 case REG_AR_BASE ... REG_AR_BASE + XCHAL_NUM_AREGS - 1:
191 tmp = regs->areg[regno - REG_AR_BASE];
192 break;
193
194 case REG_A_BASE ... REG_A_BASE + 15:
195 tmp = regs->areg[regno - REG_A_BASE];
196 break;
197
198 case REG_PC:
199 tmp = regs->pc;
200 break;
201
202 case REG_PS:
203
204
205
206
207 tmp = (regs->ps & ~(1 << PS_EXCM_BIT));
208 break;
209
210 case REG_WB:
211 break;
212
213 case REG_WS:
214 {
215 unsigned long wb = regs->windowbase;
216 unsigned long ws = regs->windowstart;
217 tmp = ((ws >> wb) | (ws << (WSBITS - wb))) &
218 ((1 << WSBITS) - 1);
219 break;
220 }
221 case REG_LBEG:
222 tmp = regs->lbeg;
223 break;
224
225 case REG_LEND:
226 tmp = regs->lend;
227 break;
228
229 case REG_LCOUNT:
230 tmp = regs->lcount;
231 break;
232
233 case REG_SAR:
234 tmp = regs->sar;
235 break;
236
237 case SYSCALL_NR:
238 tmp = regs->syscall;
239 break;
240
241 default:
242 return -EIO;
243 }
244 return put_user(tmp, ret);
245}
246
247static int ptrace_pokeusr(struct task_struct *child, long regno, long val)
248{
249 struct pt_regs *regs;
250 regs = task_pt_regs(child);
251
252 switch (regno) {
253 case REG_AR_BASE ... REG_AR_BASE + XCHAL_NUM_AREGS - 1:
254 regs->areg[regno - REG_AR_BASE] = val;
255 break;
256
257 case REG_A_BASE ... REG_A_BASE + 15:
258 regs->areg[regno - REG_A_BASE] = val;
259 break;
260
261 case REG_PC:
262 regs->pc = val;
263 break;
264
265 case SYSCALL_NR:
266 regs->syscall = val;
267 break;
268
269 default:
270 return -EIO;
271 }
272 return 0;
273}
274
275#ifdef CONFIG_HAVE_HW_BREAKPOINT
276static void ptrace_hbptriggered(struct perf_event *bp,
277 struct perf_sample_data *data,
278 struct pt_regs *regs)
279{
280 int i;
281 struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
282
283 if (bp->attr.bp_type & HW_BREAKPOINT_X) {
284 for (i = 0; i < XCHAL_NUM_IBREAK; ++i)
285 if (current->thread.ptrace_bp[i] == bp)
286 break;
287 i <<= 1;
288 } else {
289 for (i = 0; i < XCHAL_NUM_DBREAK; ++i)
290 if (current->thread.ptrace_wp[i] == bp)
291 break;
292 i = (i << 1) | 1;
293 }
294
295 force_sig_ptrace_errno_trap(i, (void __user *)bkpt->address);
296}
297
298static struct perf_event *ptrace_hbp_create(struct task_struct *tsk, int type)
299{
300 struct perf_event_attr attr;
301
302 ptrace_breakpoint_init(&attr);
303
304
305 attr.bp_addr = 0;
306 attr.bp_len = 1;
307 attr.bp_type = type;
308 attr.disabled = 1;
309
310 return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL,
311 tsk);
312}
313
314
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323
324
325
326static long ptrace_gethbpregs(struct task_struct *child, long addr,
327 long __user *datap)
328{
329 struct perf_event *bp;
330 u32 user_data[2] = {0};
331 bool dbreak = addr & 1;
332 unsigned idx = addr >> 1;
333
334 if ((!dbreak && idx >= XCHAL_NUM_IBREAK) ||
335 (dbreak && idx >= XCHAL_NUM_DBREAK))
336 return -EINVAL;
337
338 if (dbreak)
339 bp = child->thread.ptrace_wp[idx];
340 else
341 bp = child->thread.ptrace_bp[idx];
342
343 if (bp) {
344 user_data[0] = bp->attr.bp_addr;
345 user_data[1] = bp->attr.disabled ? 0 : bp->attr.bp_len;
346 if (dbreak) {
347 if (bp->attr.bp_type & HW_BREAKPOINT_R)
348 user_data[1] |= DBREAKC_LOAD_MASK;
349 if (bp->attr.bp_type & HW_BREAKPOINT_W)
350 user_data[1] |= DBREAKC_STOR_MASK;
351 }
352 }
353
354 if (copy_to_user(datap, user_data, sizeof(user_data)))
355 return -EFAULT;
356
357 return 0;
358}
359
360static long ptrace_sethbpregs(struct task_struct *child, long addr,
361 long __user *datap)
362{
363 struct perf_event *bp;
364 struct perf_event_attr attr;
365 u32 user_data[2];
366 bool dbreak = addr & 1;
367 unsigned idx = addr >> 1;
368 int bp_type = 0;
369
370 if ((!dbreak && idx >= XCHAL_NUM_IBREAK) ||
371 (dbreak && idx >= XCHAL_NUM_DBREAK))
372 return -EINVAL;
373
374 if (copy_from_user(user_data, datap, sizeof(user_data)))
375 return -EFAULT;
376
377 if (dbreak) {
378 bp = child->thread.ptrace_wp[idx];
379 if (user_data[1] & DBREAKC_LOAD_MASK)
380 bp_type |= HW_BREAKPOINT_R;
381 if (user_data[1] & DBREAKC_STOR_MASK)
382 bp_type |= HW_BREAKPOINT_W;
383 } else {
384 bp = child->thread.ptrace_bp[idx];
385 bp_type = HW_BREAKPOINT_X;
386 }
387
388 if (!bp) {
389 bp = ptrace_hbp_create(child,
390 bp_type ? bp_type : HW_BREAKPOINT_RW);
391 if (IS_ERR(bp))
392 return PTR_ERR(bp);
393 if (dbreak)
394 child->thread.ptrace_wp[idx] = bp;
395 else
396 child->thread.ptrace_bp[idx] = bp;
397 }
398
399 attr = bp->attr;
400 attr.bp_addr = user_data[0];
401 attr.bp_len = user_data[1] & ~(DBREAKC_LOAD_MASK | DBREAKC_STOR_MASK);
402 attr.bp_type = bp_type;
403 attr.disabled = !attr.bp_len;
404
405 return modify_user_hw_breakpoint(bp, &attr);
406}
407#endif
408
409long arch_ptrace(struct task_struct *child, long request,
410 unsigned long addr, unsigned long data)
411{
412 int ret = -EPERM;
413 void __user *datap = (void __user *) data;
414
415 switch (request) {
416 case PTRACE_PEEKTEXT:
417 case PTRACE_PEEKDATA:
418 ret = generic_ptrace_peekdata(child, addr, data);
419 break;
420
421 case PTRACE_PEEKUSR:
422 ret = ptrace_peekusr(child, addr, datap);
423 break;
424
425 case PTRACE_POKETEXT:
426 case PTRACE_POKEDATA:
427 ret = generic_ptrace_pokedata(child, addr, data);
428 break;
429
430 case PTRACE_POKEUSR:
431 ret = ptrace_pokeusr(child, addr, data);
432 break;
433
434 case PTRACE_GETREGS:
435 ret = ptrace_getregs(child, datap);
436 break;
437
438 case PTRACE_SETREGS:
439 ret = ptrace_setregs(child, datap);
440 break;
441
442 case PTRACE_GETXTREGS:
443 ret = ptrace_getxregs(child, datap);
444 break;
445
446 case PTRACE_SETXTREGS:
447 ret = ptrace_setxregs(child, datap);
448 break;
449#ifdef CONFIG_HAVE_HW_BREAKPOINT
450 case PTRACE_GETHBPREGS:
451 ret = ptrace_gethbpregs(child, addr, datap);
452 break;
453
454 case PTRACE_SETHBPREGS:
455 ret = ptrace_sethbpregs(child, addr, datap);
456 break;
457#endif
458 default:
459 ret = ptrace_request(child, request, addr, data);
460 break;
461 }
462
463 return ret;
464}
465
466unsigned long do_syscall_trace_enter(struct pt_regs *regs)
467{
468 if (test_thread_flag(TIF_SYSCALL_TRACE) &&
469 tracehook_report_syscall_entry(regs))
470 return -1;
471
472 return regs->areg[2];
473}
474
475void do_syscall_trace_leave(struct pt_regs *regs)
476{
477 int step;
478
479 step = test_thread_flag(TIF_SINGLESTEP);
480
481 if (step || test_thread_flag(TIF_SYSCALL_TRACE))
482 tracehook_report_syscall_exit(regs, step);
483}
484
