1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 */
5
6 #include <linux/ptrace.h>
7 #include <linux/sched/task_stack.h>
8 #include <linux/regset.h>
9 #include <linux/unistd.h>
10 #include <linux/elf.h>
11
12 #define CREATE_TRACE_POINTS
13 #include <trace/events/syscalls.h>
14
15 struct pt_regs_offset {
16 const char *name;
17 int offset;
18 };
19
20 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
21 #define REG_OFFSET_END {.name = NULL, .offset = 0}
22
23 #ifdef CONFIG_ISA_ARCOMPACT
24 static const struct pt_regs_offset regoffset_table[] = {
25 REG_OFFSET_NAME(bta),
26 REG_OFFSET_NAME(lp_start),
27 REG_OFFSET_NAME(lp_end),
28 REG_OFFSET_NAME(lp_count),
29 REG_OFFSET_NAME(status32),
30 REG_OFFSET_NAME(ret),
31 REG_OFFSET_NAME(blink),
32 REG_OFFSET_NAME(fp),
33 REG_OFFSET_NAME(r26),
34 REG_OFFSET_NAME(r12),
35 REG_OFFSET_NAME(r11),
36 REG_OFFSET_NAME(r10),
37 REG_OFFSET_NAME(r9),
38 REG_OFFSET_NAME(r8),
39 REG_OFFSET_NAME(r7),
40 REG_OFFSET_NAME(r6),
41 REG_OFFSET_NAME(r5),
42 REG_OFFSET_NAME(r4),
43 REG_OFFSET_NAME(r3),
44 REG_OFFSET_NAME(r2),
45 REG_OFFSET_NAME(r1),
46 REG_OFFSET_NAME(r0),
47 REG_OFFSET_NAME(sp),
48 REG_OFFSET_NAME(orig_r0),
49 REG_OFFSET_NAME(event),
50 REG_OFFSET_NAME(user_r25),
51 REG_OFFSET_END,
52 };
53
54 #else
55
56 static const struct pt_regs_offset regoffset_table[] = {
57 REG_OFFSET_NAME(orig_r0),
58 REG_OFFSET_NAME(event),
59 REG_OFFSET_NAME(bta),
60 REG_OFFSET_NAME(user_r25),
61 REG_OFFSET_NAME(r26),
62 REG_OFFSET_NAME(fp),
63 REG_OFFSET_NAME(sp),
64 REG_OFFSET_NAME(r12),
65 REG_OFFSET_NAME(r30),
66 #ifdef CONFIG_ARC_HAS_ACCL_REGS
67 REG_OFFSET_NAME(r58),
68 REG_OFFSET_NAME(r59),
69 #endif
70 #ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
71 REG_OFFSET_NAME(DSP_CTRL),
72 #endif
73 REG_OFFSET_NAME(r0),
74 REG_OFFSET_NAME(r1),
75 REG_OFFSET_NAME(r2),
76 REG_OFFSET_NAME(r3),
77 REG_OFFSET_NAME(r4),
78 REG_OFFSET_NAME(r5),
79 REG_OFFSET_NAME(r6),
80 REG_OFFSET_NAME(r7),
81 REG_OFFSET_NAME(r8),
82 REG_OFFSET_NAME(r9),
83 REG_OFFSET_NAME(r10),
84 REG_OFFSET_NAME(r11),
85 REG_OFFSET_NAME(blink),
86 REG_OFFSET_NAME(lp_end),
87 REG_OFFSET_NAME(lp_start),
88 REG_OFFSET_NAME(lp_count),
89 REG_OFFSET_NAME(ei),
90 REG_OFFSET_NAME(ldi),
91 REG_OFFSET_NAME(jli),
92 REG_OFFSET_NAME(ret),
93 REG_OFFSET_NAME(status32),
94 REG_OFFSET_END,
95 };
96 #endif
97
task_callee_regs(struct task_struct * tsk)98 static struct callee_regs *task_callee_regs(struct task_struct *tsk)
99 {
100 struct callee_regs *tmp = (struct callee_regs *)tsk->thread.callee_reg;
101 return tmp;
102 }
103
genregs_get(struct task_struct * target,const struct user_regset * regset,struct membuf to)104 static int genregs_get(struct task_struct *target,
105 const struct user_regset *regset,
106 struct membuf to)
107 {
108 const struct pt_regs *ptregs = task_pt_regs(target);
109 const struct callee_regs *cregs = task_callee_regs(target);
110 unsigned int stop_pc_val;
111
112 membuf_zero(&to, 4); // pad
113 membuf_store(&to, ptregs->bta);
114 membuf_store(&to, ptregs->lp_start);
115 membuf_store(&to, ptregs->lp_end);
116 membuf_store(&to, ptregs->lp_count);
117 membuf_store(&to, ptregs->status32);
118 membuf_store(&to, ptregs->ret);
119 membuf_store(&to, ptregs->blink);
120 membuf_store(&to, ptregs->fp);
121 membuf_store(&to, ptregs->r26); // gp
122 membuf_store(&to, ptregs->r12);
123 membuf_store(&to, ptregs->r11);
124 membuf_store(&to, ptregs->r10);
125 membuf_store(&to, ptregs->r9);
126 membuf_store(&to, ptregs->r8);
127 membuf_store(&to, ptregs->r7);
128 membuf_store(&to, ptregs->r6);
129 membuf_store(&to, ptregs->r5);
130 membuf_store(&to, ptregs->r4);
131 membuf_store(&to, ptregs->r3);
132 membuf_store(&to, ptregs->r2);
133 membuf_store(&to, ptregs->r1);
134 membuf_store(&to, ptregs->r0);
135 membuf_store(&to, ptregs->sp);
136 membuf_zero(&to, 4); // pad2
137 membuf_store(&to, cregs->r25);
138 membuf_store(&to, cregs->r24);
139 membuf_store(&to, cregs->r23);
140 membuf_store(&to, cregs->r22);
141 membuf_store(&to, cregs->r21);
142 membuf_store(&to, cregs->r20);
143 membuf_store(&to, cregs->r19);
144 membuf_store(&to, cregs->r18);
145 membuf_store(&to, cregs->r17);
146 membuf_store(&to, cregs->r16);
147 membuf_store(&to, cregs->r15);
148 membuf_store(&to, cregs->r14);
149 membuf_store(&to, cregs->r13);
150 membuf_store(&to, target->thread.fault_address); // efa
151
152 if (in_brkpt_trap(ptregs)) {
153 stop_pc_val = target->thread.fault_address;
154 pr_debug("\t\tstop_pc (brk-pt)\n");
155 } else {
156 stop_pc_val = ptregs->ret;
157 pr_debug("\t\tstop_pc (others)\n");
158 }
159
160 return membuf_store(&to, stop_pc_val); // stop_pc
161 }
162
genregs_set(struct task_struct * target,const struct user_regset * regset,unsigned int pos,unsigned int count,const void * kbuf,const void __user * ubuf)163 static int genregs_set(struct task_struct *target,
164 const struct user_regset *regset,
165 unsigned int pos, unsigned int count,
166 const void *kbuf, const void __user *ubuf)
167 {
168 const struct pt_regs *ptregs = task_pt_regs(target);
169 const struct callee_regs *cregs = task_callee_regs(target);
170 int ret = 0;
171
172 #define REG_IN_CHUNK(FIRST, NEXT, PTR) \
173 if (!ret) \
174 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
175 (void *)(PTR), \
176 offsetof(struct user_regs_struct, FIRST), \
177 offsetof(struct user_regs_struct, NEXT));
178
179 #define REG_IN_ONE(LOC, PTR) \
180 if (!ret) \
181 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
182 (void *)(PTR), \
183 offsetof(struct user_regs_struct, LOC), \
184 offsetof(struct user_regs_struct, LOC) + 4);
185
186 #define REG_IGNORE_ONE(LOC) \
187 if (!ret) \
188 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
189 offsetof(struct user_regs_struct, LOC), \
190 offsetof(struct user_regs_struct, LOC) + 4);
191
192 REG_IGNORE_ONE(pad);
193
194 REG_IN_ONE(scratch.bta, &ptregs->bta);
195 REG_IN_ONE(scratch.lp_start, &ptregs->lp_start);
196 REG_IN_ONE(scratch.lp_end, &ptregs->lp_end);
197 REG_IN_ONE(scratch.lp_count, &ptregs->lp_count);
198
199 REG_IGNORE_ONE(scratch.status32);
200
201 REG_IN_ONE(scratch.ret, &ptregs->ret);
202 REG_IN_ONE(scratch.blink, &ptregs->blink);
203 REG_IN_ONE(scratch.fp, &ptregs->fp);
204 REG_IN_ONE(scratch.gp, &ptregs->r26);
205 REG_IN_ONE(scratch.r12, &ptregs->r12);
206 REG_IN_ONE(scratch.r11, &ptregs->r11);
207 REG_IN_ONE(scratch.r10, &ptregs->r10);
208 REG_IN_ONE(scratch.r9, &ptregs->r9);
209 REG_IN_ONE(scratch.r8, &ptregs->r8);
210 REG_IN_ONE(scratch.r7, &ptregs->r7);
211 REG_IN_ONE(scratch.r6, &ptregs->r6);
212 REG_IN_ONE(scratch.r5, &ptregs->r5);
213 REG_IN_ONE(scratch.r4, &ptregs->r4);
214 REG_IN_ONE(scratch.r3, &ptregs->r3);
215 REG_IN_ONE(scratch.r2, &ptregs->r2);
216 REG_IN_ONE(scratch.r1, &ptregs->r1);
217 REG_IN_ONE(scratch.r0, &ptregs->r0);
218 REG_IN_ONE(scratch.sp, &ptregs->sp);
219
220 REG_IGNORE_ONE(pad2);
221
222 REG_IN_ONE(callee.r25, &cregs->r25);
223 REG_IN_ONE(callee.r24, &cregs->r24);
224 REG_IN_ONE(callee.r23, &cregs->r23);
225 REG_IN_ONE(callee.r22, &cregs->r22);
226 REG_IN_ONE(callee.r21, &cregs->r21);
227 REG_IN_ONE(callee.r20, &cregs->r20);
228 REG_IN_ONE(callee.r19, &cregs->r19);
229 REG_IN_ONE(callee.r18, &cregs->r18);
230 REG_IN_ONE(callee.r17, &cregs->r17);
231 REG_IN_ONE(callee.r16, &cregs->r16);
232 REG_IN_ONE(callee.r15, &cregs->r15);
233 REG_IN_ONE(callee.r14, &cregs->r14);
234 REG_IN_ONE(callee.r13, &cregs->r13);
235
236 REG_IGNORE_ONE(efa); /* efa update invalid */
237 REG_IGNORE_ONE(stop_pc); /* PC updated via @ret */
238
239 return ret;
240 }
241
242 #ifdef CONFIG_ISA_ARCV2
arcv2regs_get(struct task_struct * target,const struct user_regset * regset,struct membuf to)243 static int arcv2regs_get(struct task_struct *target,
244 const struct user_regset *regset,
245 struct membuf to)
246 {
247 const struct pt_regs *regs = task_pt_regs(target);
248
249 if (IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS))
250 /*
251 * itemized copy not needed like above as layout of regs (r30,r58,r59)
252 * is exactly same in kernel (pt_regs) and userspace (user_regs_arcv2)
253 */
254 return membuf_write(&to, ®s->r30, sizeof(struct user_regs_arcv2));
255
256
257 membuf_write(&to, ®s->r30, 4); /* r30 only */
258 return membuf_zero(&to, sizeof(struct user_regs_arcv2) - 4);
259 }
260
arcv2regs_set(struct task_struct * target,const struct user_regset * regset,unsigned int pos,unsigned int count,const void * kbuf,const void __user * ubuf)261 static int arcv2regs_set(struct task_struct *target,
262 const struct user_regset *regset,
263 unsigned int pos, unsigned int count,
264 const void *kbuf, const void __user *ubuf)
265 {
266 const struct pt_regs *regs = task_pt_regs(target);
267 int ret, copy_sz;
268
269 if (IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS))
270 copy_sz = sizeof(struct user_regs_arcv2);
271 else
272 copy_sz = 4; /* r30 only */
273
274 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, (void *)®s->r30,
275 0, copy_sz);
276
277 return ret;
278 }
279
280 #endif
281
282 enum arc_getset {
283 REGSET_CMN,
284 REGSET_ARCV2,
285 };
286
287 static const struct user_regset arc_regsets[] = {
288 [REGSET_CMN] = {
289 .core_note_type = NT_PRSTATUS,
290 .n = ELF_NGREG,
291 .size = sizeof(unsigned long),
292 .align = sizeof(unsigned long),
293 .regset_get = genregs_get,
294 .set = genregs_set,
295 },
296 #ifdef CONFIG_ISA_ARCV2
297 [REGSET_ARCV2] = {
298 .core_note_type = NT_ARC_V2,
299 .n = ELF_ARCV2REG,
300 .size = sizeof(unsigned long),
301 .align = sizeof(unsigned long),
302 .regset_get = arcv2regs_get,
303 .set = arcv2regs_set,
304 },
305 #endif
306 };
307
308 static const struct user_regset_view user_arc_view = {
309 .name = "arc",
310 .e_machine = EM_ARC_INUSE,
311 .regsets = arc_regsets,
312 .n = ARRAY_SIZE(arc_regsets)
313 };
314
task_user_regset_view(struct task_struct * task)315 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
316 {
317 return &user_arc_view;
318 }
319
ptrace_disable(struct task_struct * child)320 void ptrace_disable(struct task_struct *child)
321 {
322 }
323
arch_ptrace(struct task_struct * child,long request,unsigned long addr,unsigned long data)324 long arch_ptrace(struct task_struct *child, long request,
325 unsigned long addr, unsigned long data)
326 {
327 int ret = -EIO;
328
329 pr_debug("REQ=%ld: ADDR =0x%lx, DATA=0x%lx)\n", request, addr, data);
330
331 switch (request) {
332 case PTRACE_GET_THREAD_AREA:
333 ret = put_user(task_thread_info(child)->thr_ptr,
334 (unsigned long __user *)data);
335 break;
336 default:
337 ret = ptrace_request(child, request, addr, data);
338 break;
339 }
340
341 return ret;
342 }
343
syscall_trace_entry(struct pt_regs * regs)344 asmlinkage int syscall_trace_entry(struct pt_regs *regs)
345 {
346 if (test_thread_flag(TIF_SYSCALL_TRACE))
347 if (ptrace_report_syscall_entry(regs))
348 return ULONG_MAX;
349
350 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
351 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
352 trace_sys_enter(regs, syscall_get_nr(current, regs));
353 #endif
354
355 return regs->r8;
356 }
357
syscall_trace_exit(struct pt_regs * regs)358 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
359 {
360 if (test_thread_flag(TIF_SYSCALL_TRACE))
361 ptrace_report_syscall_exit(regs, 0);
362
363 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
364 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
365 trace_sys_exit(regs, regs_return_value(regs));
366 #endif
367 }
368
regs_query_register_offset(const char * name)369 int regs_query_register_offset(const char *name)
370 {
371 const struct pt_regs_offset *roff;
372
373 for (roff = regoffset_table; roff->name != NULL; roff++)
374 if (!strcmp(roff->name, name))
375 return roff->offset;
376 return -EINVAL;
377 }
378
regs_query_register_name(unsigned int offset)379 const char *regs_query_register_name(unsigned int offset)
380 {
381 const struct pt_regs_offset *roff;
382 for (roff = regoffset_table; roff->name != NULL; roff++)
383 if (roff->offset == offset)
384 return roff->name;
385 return NULL;
386 }
387
regs_within_kernel_stack(struct pt_regs * regs,unsigned long addr)388 bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
389 {
390 return (addr & ~(THREAD_SIZE - 1)) ==
391 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1));
392 }
393
regs_get_kernel_stack_nth(struct pt_regs * regs,unsigned int n)394 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
395 {
396 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
397
398 addr += n;
399 if (regs_within_kernel_stack(regs, (unsigned long)addr))
400 return *addr;
401 else
402 return 0;
403 }
404
