Linux-libre 5.7.5-gnu
[librecmc/linux-libre.git] / arch / sparc / kernel / ptrace_32.c
1 // SPDX-License-Identifier: GPL-2.0
2 /* ptrace.c: Sparc process tracing support.
3  *
4  * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
5  *
6  * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
7  * and David Mosberger.
8  *
9  * Added Linux support -miguel (weird, eh?, the original code was meant
10  * to emulate SunOS).
11  */
12
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/mm.h>
16 #include <linux/errno.h>
17 #include <linux/ptrace.h>
18 #include <linux/user.h>
19 #include <linux/smp.h>
20 #include <linux/security.h>
21 #include <linux/signal.h>
22 #include <linux/regset.h>
23 #include <linux/elf.h>
24 #include <linux/tracehook.h>
25
26 #include <asm/pgtable.h>
27 #include <linux/uaccess.h>
28 #include <asm/cacheflush.h>
29
30 #include "kernel.h"
31
32 /* #define ALLOW_INIT_TRACING */
33
34 /*
35  * Called by kernel/ptrace.c when detaching..
36  *
37  * Make sure single step bits etc are not set.
38  */
39 void ptrace_disable(struct task_struct *child)
40 {
41         /* nothing to do */
42 }
43
44 enum sparc_regset {
45         REGSET_GENERAL,
46         REGSET_FP,
47 };
48
49 static int regwindow32_get(struct task_struct *target,
50                            const struct pt_regs *regs,
51                            u32 *uregs)
52 {
53         unsigned long reg_window = regs->u_regs[UREG_I6];
54         int size = 16 * sizeof(u32);
55
56         if (target == current) {
57                 if (copy_from_user(uregs, (void __user *)reg_window, size))
58                         return -EFAULT;
59         } else {
60                 if (access_process_vm(target, reg_window, uregs, size,
61                                       FOLL_FORCE) != size)
62                         return -EFAULT;
63         }
64         return 0;
65 }
66
67 static int regwindow32_set(struct task_struct *target,
68                            const struct pt_regs *regs,
69                            u32 *uregs)
70 {
71         unsigned long reg_window = regs->u_regs[UREG_I6];
72         int size = 16 * sizeof(u32);
73
74         if (target == current) {
75                 if (copy_to_user((void __user *)reg_window, uregs, size))
76                         return -EFAULT;
77         } else {
78                 if (access_process_vm(target, reg_window, uregs, size,
79                                       FOLL_FORCE | FOLL_WRITE) != size)
80                         return -EFAULT;
81         }
82         return 0;
83 }
84
85 static int genregs32_get(struct task_struct *target,
86                          const struct user_regset *regset,
87                          unsigned int pos, unsigned int count,
88                          void *kbuf, void __user *ubuf)
89 {
90         const struct pt_regs *regs = target->thread.kregs;
91         u32 uregs[16];
92         int ret;
93
94         if (target == current)
95                 flush_user_windows();
96
97         ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
98                                   regs->u_regs,
99                                   0, 16 * sizeof(u32));
100         if (ret || !count)
101                 return ret;
102
103         if (pos < 32 * sizeof(u32)) {
104                 if (regwindow32_get(target, regs, uregs))
105                         return -EFAULT;
106                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
107                                           uregs,
108                                           16 * sizeof(u32), 32 * sizeof(u32));
109                 if (ret || !count)
110                         return ret;
111         }
112
113         uregs[0] = regs->psr;
114         uregs[1] = regs->pc;
115         uregs[2] = regs->npc;
116         uregs[3] = regs->y;
117         uregs[4] = 0;   /* WIM */
118         uregs[5] = 0;   /* TBR */
119         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
120                                   uregs,
121                                   32 * sizeof(u32), 38 * sizeof(u32));
122 }
123
124 static int genregs32_set(struct task_struct *target,
125                          const struct user_regset *regset,
126                          unsigned int pos, unsigned int count,
127                          const void *kbuf, const void __user *ubuf)
128 {
129         struct pt_regs *regs = target->thread.kregs;
130         u32 uregs[16];
131         u32 psr;
132         int ret;
133
134         if (target == current)
135                 flush_user_windows();
136
137         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
138                                  regs->u_regs,
139                                  0, 16 * sizeof(u32));
140         if (ret || !count)
141                 return ret;
142
143         if (pos < 32 * sizeof(u32)) {
144                 if (regwindow32_get(target, regs, uregs))
145                         return -EFAULT;
146                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
147                                          uregs,
148                                          16 * sizeof(u32), 32 * sizeof(u32));
149                 if (ret)
150                         return ret;
151                 if (regwindow32_set(target, regs, uregs))
152                         return -EFAULT;
153                 if (!count)
154                         return 0;
155         }
156         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
157                                  &psr,
158                                  32 * sizeof(u32), 33 * sizeof(u32));
159         if (ret)
160                 return ret;
161         regs->psr = (regs->psr & ~(PSR_ICC | PSR_SYSCALL)) |
162                     (psr & (PSR_ICC | PSR_SYSCALL));
163         if (!count)
164                 return 0;
165         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
166                                  &regs->pc,
167                                  33 * sizeof(u32), 34 * sizeof(u32));
168         if (ret || !count)
169                 return ret;
170         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
171                                  &regs->y,
172                                  34 * sizeof(u32), 35 * sizeof(u32));
173         if (ret || !count)
174                 return ret;
175         return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
176                                          35 * sizeof(u32), 38 * sizeof(u32));
177 }
178
179 static int fpregs32_get(struct task_struct *target,
180                         const struct user_regset *regset,
181                         unsigned int pos, unsigned int count,
182                         void *kbuf, void __user *ubuf)
183 {
184         const unsigned long *fpregs = target->thread.float_regs;
185         int ret = 0;
186
187 #if 0
188         if (target == current)
189                 save_and_clear_fpu();
190 #endif
191
192         ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
193                                   fpregs,
194                                   0, 32 * sizeof(u32));
195
196         if (!ret)
197                 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
198                                                32 * sizeof(u32),
199                                                33 * sizeof(u32));
200         if (!ret)
201                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
202                                           &target->thread.fsr,
203                                           33 * sizeof(u32),
204                                           34 * sizeof(u32));
205
206         if (!ret) {
207                 unsigned long val;
208
209                 val = (1 << 8) | (8 << 16);
210                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
211                                           &val,
212                                           34 * sizeof(u32),
213                                           35 * sizeof(u32));
214         }
215
216         if (!ret)
217                 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
218                                                35 * sizeof(u32), -1);
219
220         return ret;
221 }
222
223 static int fpregs32_set(struct task_struct *target,
224                         const struct user_regset *regset,
225                         unsigned int pos, unsigned int count,
226                         const void *kbuf, const void __user *ubuf)
227 {
228         unsigned long *fpregs = target->thread.float_regs;
229         int ret;
230
231 #if 0
232         if (target == current)
233                 save_and_clear_fpu();
234 #endif
235         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
236                                  fpregs,
237                                  0, 32 * sizeof(u32));
238         if (!ret)
239                 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
240                                           32 * sizeof(u32),
241                                           33 * sizeof(u32));
242         if (!ret && count > 0) {
243                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
244                                          &target->thread.fsr,
245                                          33 * sizeof(u32),
246                                          34 * sizeof(u32));
247         }
248
249         if (!ret)
250                 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
251                                                 34 * sizeof(u32), -1);
252         return ret;
253 }
254
255 static const struct user_regset sparc32_regsets[] = {
256         /* Format is:
257          *      G0 --> G7
258          *      O0 --> O7
259          *      L0 --> L7
260          *      I0 --> I7
261          *      PSR, PC, nPC, Y, WIM, TBR
262          */
263         [REGSET_GENERAL] = {
264                 .core_note_type = NT_PRSTATUS,
265                 .n = 38,
266                 .size = sizeof(u32), .align = sizeof(u32),
267                 .get = genregs32_get, .set = genregs32_set
268         },
269         /* Format is:
270          *      F0 --> F31
271          *      empty 32-bit word
272          *      FSR (32--bit word)
273          *      FPU QUEUE COUNT (8-bit char)
274          *      FPU QUEUE ENTRYSIZE (8-bit char)
275          *      FPU ENABLED (8-bit char)
276          *      empty 8-bit char
277          *      FPU QUEUE (64 32-bit ints)
278          */
279         [REGSET_FP] = {
280                 .core_note_type = NT_PRFPREG,
281                 .n = 99,
282                 .size = sizeof(u32), .align = sizeof(u32),
283                 .get = fpregs32_get, .set = fpregs32_set
284         },
285 };
286
287 static const struct user_regset_view user_sparc32_view = {
288         .name = "sparc", .e_machine = EM_SPARC,
289         .regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
290 };
291
292 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
293 {
294         return &user_sparc32_view;
295 }
296
297 struct fps {
298         unsigned long regs[32];
299         unsigned long fsr;
300         unsigned long flags;
301         unsigned long extra;
302         unsigned long fpqd;
303         struct fq {
304                 unsigned long *insnaddr;
305                 unsigned long insn;
306         } fpq[16];
307 };
308
309 long arch_ptrace(struct task_struct *child, long request,
310                  unsigned long addr, unsigned long data)
311 {
312         unsigned long addr2 = current->thread.kregs->u_regs[UREG_I4];
313         void __user *addr2p;
314         const struct user_regset_view *view;
315         struct pt_regs __user *pregs;
316         struct fps __user *fps;
317         int ret;
318
319         view = task_user_regset_view(current);
320         addr2p = (void __user *) addr2;
321         pregs = (struct pt_regs __user *) addr;
322         fps = (struct fps __user *) addr;
323
324         switch(request) {
325         case PTRACE_GETREGS: {
326                 ret = copy_regset_to_user(child, view, REGSET_GENERAL,
327                                           32 * sizeof(u32),
328                                           4 * sizeof(u32),
329                                           &pregs->psr);
330                 if (!ret)
331                         copy_regset_to_user(child, view, REGSET_GENERAL,
332                                             1 * sizeof(u32),
333                                             15 * sizeof(u32),
334                                             &pregs->u_regs[0]);
335                 break;
336         }
337
338         case PTRACE_SETREGS: {
339                 ret = copy_regset_from_user(child, view, REGSET_GENERAL,
340                                             32 * sizeof(u32),
341                                             4 * sizeof(u32),
342                                             &pregs->psr);
343                 if (!ret)
344                         copy_regset_from_user(child, view, REGSET_GENERAL,
345                                               1 * sizeof(u32),
346                                               15 * sizeof(u32),
347                                               &pregs->u_regs[0]);
348                 break;
349         }
350
351         case PTRACE_GETFPREGS: {
352                 ret = copy_regset_to_user(child, view, REGSET_FP,
353                                           0 * sizeof(u32),
354                                           32 * sizeof(u32),
355                                           &fps->regs[0]);
356                 if (!ret)
357                         ret = copy_regset_to_user(child, view, REGSET_FP,
358                                                   33 * sizeof(u32),
359                                                   1 * sizeof(u32),
360                                                   &fps->fsr);
361
362                 if (!ret) {
363                         if (__put_user(0, &fps->fpqd) ||
364                             __put_user(0, &fps->flags) ||
365                             __put_user(0, &fps->extra) ||
366                             clear_user(fps->fpq, sizeof(fps->fpq)))
367                                 ret = -EFAULT;
368                 }
369                 break;
370         }
371
372         case PTRACE_SETFPREGS: {
373                 ret = copy_regset_from_user(child, view, REGSET_FP,
374                                             0 * sizeof(u32),
375                                             32 * sizeof(u32),
376                                             &fps->regs[0]);
377                 if (!ret)
378                         ret = copy_regset_from_user(child, view, REGSET_FP,
379                                                     33 * sizeof(u32),
380                                                     1 * sizeof(u32),
381                                                     &fps->fsr);
382                 break;
383         }
384
385         case PTRACE_READTEXT:
386         case PTRACE_READDATA:
387                 ret = ptrace_readdata(child, addr, addr2p, data);
388
389                 if (ret == data)
390                         ret = 0;
391                 else if (ret >= 0)
392                         ret = -EIO;
393                 break;
394
395         case PTRACE_WRITETEXT:
396         case PTRACE_WRITEDATA:
397                 ret = ptrace_writedata(child, addr2p, addr, data);
398
399                 if (ret == data)
400                         ret = 0;
401                 else if (ret >= 0)
402                         ret = -EIO;
403                 break;
404
405         default:
406                 if (request == PTRACE_SPARC_DETACH)
407                         request = PTRACE_DETACH;
408                 ret = ptrace_request(child, request, addr, data);
409                 break;
410         }
411
412         return ret;
413 }
414
415 asmlinkage int syscall_trace(struct pt_regs *regs, int syscall_exit_p)
416 {
417         int ret = 0;
418
419         if (test_thread_flag(TIF_SYSCALL_TRACE)) {
420                 if (syscall_exit_p)
421                         tracehook_report_syscall_exit(regs, 0);
422                 else
423                         ret = tracehook_report_syscall_entry(regs);
424         }
425
426         return ret;
427 }