1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. 3 4 #include <linux/audit.h> 5 #include <linux/elf.h> 6 #include <linux/errno.h> 7 #include <linux/kernel.h> 8 #include <linux/mm.h> 9 #include <linux/ptrace.h> 10 #include <linux/regset.h> 11 #include <linux/sched.h> 12 #include <linux/sched/task_stack.h> 13 #include <linux/signal.h> 14 #include <linux/smp.h> 15 #include <linux/tracehook.h> 16 #include <linux/uaccess.h> 17 #include <linux/user.h> 18 19 #include <asm/thread_info.h> 20 #include <asm/page.h> 21 #include <asm/processor.h> 22 #include <asm/asm-offsets.h> 23 24 #include <abi/regdef.h> 25 26 #define CREATE_TRACE_POINTS 27 #include <trace/events/syscalls.h> 28 29 /* sets the trace bits. */ 30 #define TRACE_MODE_SI (1 << 14) 31 #define TRACE_MODE_RUN 0 32 #define TRACE_MODE_MASK ~(0x3 << 14) 33 34 /* 35 * Make sure the single step bit is not set. 36 */ 37 static void singlestep_disable(struct task_struct *tsk) 38 { 39 struct pt_regs *regs; 40 41 regs = task_pt_regs(tsk); 42 regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_RUN; 43 44 /* Enable irq */ 45 regs->sr |= BIT(6); 46 } 47 48 static void singlestep_enable(struct task_struct *tsk) 49 { 50 struct pt_regs *regs; 51 52 regs = task_pt_regs(tsk); 53 regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_SI; 54 55 /* Disable irq */ 56 regs->sr &= ~BIT(6); 57 } 58 59 /* 60 * Make sure the single step bit is set. 61 */ 62 void user_enable_single_step(struct task_struct *child) 63 { 64 singlestep_enable(child); 65 } 66 67 void user_disable_single_step(struct task_struct *child) 68 { 69 singlestep_disable(child); 70 } 71 72 enum csky_regset { 73 REGSET_GPR, 74 REGSET_FPR, 75 }; 76 77 static int gpr_get(struct task_struct *target, 78 const struct user_regset *regset, 79 unsigned int pos, unsigned int count, 80 void *kbuf, void __user *ubuf) 81 { 82 struct pt_regs *regs; 83 84 regs = task_pt_regs(target); 85 86 /* Abiv1 regs->tls is fake and we need sync here. */ 87 regs->tls = task_thread_info(target)->tp_value; 88 89 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1); 90 } 91 92 static int gpr_set(struct task_struct *target, 93 const struct user_regset *regset, 94 unsigned int pos, unsigned int count, 95 const void *kbuf, const void __user *ubuf) 96 { 97 int ret; 98 struct pt_regs regs; 99 100 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, ®s, 0, -1); 101 if (ret) 102 return ret; 103 104 regs.sr = task_pt_regs(target)->sr; 105 #ifdef CONFIG_CPU_HAS_HILO 106 regs.dcsr = task_pt_regs(target)->dcsr; 107 #endif 108 task_thread_info(target)->tp_value = regs.tls; 109 110 *task_pt_regs(target) = regs; 111 112 return 0; 113 } 114 115 static int fpr_get(struct task_struct *target, 116 const struct user_regset *regset, 117 unsigned int pos, unsigned int count, 118 void *kbuf, void __user *ubuf) 119 { 120 struct user_fp *regs = (struct user_fp *)&target->thread.user_fp; 121 122 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP) 123 int i; 124 struct user_fp tmp = *regs; 125 126 for (i = 0; i < 16; i++) { 127 tmp.vr[i*4] = regs->vr[i*2]; 128 tmp.vr[i*4 + 1] = regs->vr[i*2 + 1]; 129 } 130 131 for (i = 0; i < 32; i++) 132 tmp.vr[64 + i] = regs->vr[32 + i]; 133 134 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1); 135 #else 136 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1); 137 #endif 138 } 139 140 static int fpr_set(struct task_struct *target, 141 const struct user_regset *regset, 142 unsigned int pos, unsigned int count, 143 const void *kbuf, const void __user *ubuf) 144 { 145 int ret; 146 struct user_fp *regs = (struct user_fp *)&target->thread.user_fp; 147 148 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP) 149 int i; 150 struct user_fp tmp; 151 152 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1); 153 154 *regs = tmp; 155 156 for (i = 0; i < 16; i++) { 157 regs->vr[i*2] = tmp.vr[i*4]; 158 regs->vr[i*2 + 1] = tmp.vr[i*4 + 1]; 159 } 160 161 for (i = 0; i < 32; i++) 162 regs->vr[32 + i] = tmp.vr[64 + i]; 163 #else 164 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1); 165 #endif 166 167 return ret; 168 } 169 170 static const struct user_regset csky_regsets[] = { 171 [REGSET_GPR] = { 172 .core_note_type = NT_PRSTATUS, 173 .n = sizeof(struct pt_regs) / sizeof(u32), 174 .size = sizeof(u32), 175 .align = sizeof(u32), 176 .get = &gpr_get, 177 .set = &gpr_set, 178 }, 179 [REGSET_FPR] = { 180 .core_note_type = NT_PRFPREG, 181 .n = sizeof(struct user_fp) / sizeof(u32), 182 .size = sizeof(u32), 183 .align = sizeof(u32), 184 .get = &fpr_get, 185 .set = &fpr_set, 186 }, 187 }; 188 189 static const struct user_regset_view user_csky_view = { 190 .name = "csky", 191 .e_machine = ELF_ARCH, 192 .regsets = csky_regsets, 193 .n = ARRAY_SIZE(csky_regsets), 194 }; 195 196 const struct user_regset_view *task_user_regset_view(struct task_struct *task) 197 { 198 return &user_csky_view; 199 } 200 201 struct pt_regs_offset { 202 const char *name; 203 int offset; 204 }; 205 206 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} 207 #define REG_OFFSET_END {.name = NULL, .offset = 0} 208 209 static const struct pt_regs_offset regoffset_table[] = { 210 REG_OFFSET_NAME(tls), 211 REG_OFFSET_NAME(lr), 212 REG_OFFSET_NAME(pc), 213 REG_OFFSET_NAME(sr), 214 REG_OFFSET_NAME(usp), 215 REG_OFFSET_NAME(orig_a0), 216 REG_OFFSET_NAME(a0), 217 REG_OFFSET_NAME(a1), 218 REG_OFFSET_NAME(a2), 219 REG_OFFSET_NAME(a3), 220 REG_OFFSET_NAME(regs[0]), 221 REG_OFFSET_NAME(regs[1]), 222 REG_OFFSET_NAME(regs[2]), 223 REG_OFFSET_NAME(regs[3]), 224 REG_OFFSET_NAME(regs[4]), 225 REG_OFFSET_NAME(regs[5]), 226 REG_OFFSET_NAME(regs[6]), 227 REG_OFFSET_NAME(regs[7]), 228 REG_OFFSET_NAME(regs[8]), 229 REG_OFFSET_NAME(regs[9]), 230 #if defined(__CSKYABIV2__) 231 REG_OFFSET_NAME(exregs[0]), 232 REG_OFFSET_NAME(exregs[1]), 233 REG_OFFSET_NAME(exregs[2]), 234 REG_OFFSET_NAME(exregs[3]), 235 REG_OFFSET_NAME(exregs[4]), 236 REG_OFFSET_NAME(exregs[5]), 237 REG_OFFSET_NAME(exregs[6]), 238 REG_OFFSET_NAME(exregs[7]), 239 REG_OFFSET_NAME(exregs[8]), 240 REG_OFFSET_NAME(exregs[9]), 241 REG_OFFSET_NAME(exregs[10]), 242 REG_OFFSET_NAME(exregs[11]), 243 REG_OFFSET_NAME(exregs[12]), 244 REG_OFFSET_NAME(exregs[13]), 245 REG_OFFSET_NAME(exregs[14]), 246 REG_OFFSET_NAME(rhi), 247 REG_OFFSET_NAME(rlo), 248 REG_OFFSET_NAME(dcsr), 249 #endif 250 REG_OFFSET_END, 251 }; 252 253 /** 254 * regs_query_register_offset() - query register offset from its name 255 * @name: the name of a register 256 * 257 * regs_query_register_offset() returns the offset of a register in struct 258 * pt_regs from its name. If the name is invalid, this returns -EINVAL; 259 */ 260 int regs_query_register_offset(const char *name) 261 { 262 const struct pt_regs_offset *roff; 263 264 for (roff = regoffset_table; roff->name != NULL; roff++) 265 if (!strcmp(roff->name, name)) 266 return roff->offset; 267 return -EINVAL; 268 } 269 270 /** 271 * regs_within_kernel_stack() - check the address in the stack 272 * @regs: pt_regs which contains kernel stack pointer. 273 * @addr: address which is checked. 274 * 275 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). 276 * If @addr is within the kernel stack, it returns true. If not, returns false. 277 */ 278 static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) 279 { 280 return (addr & ~(THREAD_SIZE - 1)) == 281 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)); 282 } 283 284 /** 285 * regs_get_kernel_stack_nth() - get Nth entry of the stack 286 * @regs: pt_regs which contains kernel stack pointer. 287 * @n: stack entry number. 288 * 289 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which 290 * is specified by @regs. If the @n th entry is NOT in the kernel stack, 291 * this returns 0. 292 */ 293 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) 294 { 295 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); 296 297 addr += n; 298 if (regs_within_kernel_stack(regs, (unsigned long)addr)) 299 return *addr; 300 else 301 return 0; 302 } 303 304 void ptrace_disable(struct task_struct *child) 305 { 306 singlestep_disable(child); 307 } 308 309 long arch_ptrace(struct task_struct *child, long request, 310 unsigned long addr, unsigned long data) 311 { 312 long ret = -EIO; 313 314 switch (request) { 315 default: 316 ret = ptrace_request(child, request, addr, data); 317 break; 318 } 319 320 return ret; 321 } 322 323 asmlinkage int syscall_trace_enter(struct pt_regs *regs) 324 { 325 if (test_thread_flag(TIF_SYSCALL_TRACE)) 326 if (tracehook_report_syscall_entry(regs)) 327 return -1; 328 329 if (secure_computing() == -1) 330 return -1; 331 332 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) 333 trace_sys_enter(regs, syscall_get_nr(current, regs)); 334 335 audit_syscall_entry(regs_syscallid(regs), regs->a0, regs->a1, regs->a2, regs->a3); 336 return 0; 337 } 338 339 asmlinkage void syscall_trace_exit(struct pt_regs *regs) 340 { 341 audit_syscall_exit(regs); 342 343 if (test_thread_flag(TIF_SYSCALL_TRACE)) 344 tracehook_report_syscall_exit(regs, 0); 345 346 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) 347 trace_sys_exit(regs, syscall_get_return_value(current, regs)); 348 } 349 350 void show_regs(struct pt_regs *fp) 351 { 352 pr_info("\nCURRENT PROCESS:\n\n"); 353 pr_info("COMM=%s PID=%d\n", current->comm, current->pid); 354 355 if (current->mm) { 356 pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n", 357 (int) current->mm->start_code, 358 (int) current->mm->end_code, 359 (int) current->mm->start_data, 360 (int) current->mm->end_data, 361 (int) current->mm->end_data, 362 (int) current->mm->brk); 363 pr_info("USER-STACK=%08x KERNEL-STACK=%08x\n\n", 364 (int) current->mm->start_stack, 365 (int) (((unsigned long) current) + 2 * PAGE_SIZE)); 366 } 367 368 pr_info("PC: 0x%08lx (%pS)\n", (long)fp->pc, (void *)fp->pc); 369 pr_info("LR: 0x%08lx (%pS)\n", (long)fp->lr, (void *)fp->lr); 370 pr_info("SP: 0x%08lx\n", (long)fp); 371 pr_info("orig_a0: 0x%08lx\n", fp->orig_a0); 372 pr_info("PSR: 0x%08lx\n", (long)fp->sr); 373 374 pr_info(" a0: 0x%08lx a1: 0x%08lx a2: 0x%08lx a3: 0x%08lx\n", 375 fp->a0, fp->a1, fp->a2, fp->a3); 376 #if defined(__CSKYABIV2__) 377 pr_info(" r4: 0x%08lx r5: 0x%08lx r6: 0x%08lx r7: 0x%08lx\n", 378 fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]); 379 pr_info(" r8: 0x%08lx r9: 0x%08lx r10: 0x%08lx r11: 0x%08lx\n", 380 fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]); 381 pr_info("r12: 0x%08lx r13: 0x%08lx r15: 0x%08lx\n", 382 fp->regs[8], fp->regs[9], fp->lr); 383 pr_info("r16: 0x%08lx r17: 0x%08lx r18: 0x%08lx r19: 0x%08lx\n", 384 fp->exregs[0], fp->exregs[1], fp->exregs[2], fp->exregs[3]); 385 pr_info("r20: 0x%08lx r21: 0x%08lx r22: 0x%08lx r23: 0x%08lx\n", 386 fp->exregs[4], fp->exregs[5], fp->exregs[6], fp->exregs[7]); 387 pr_info("r24: 0x%08lx r25: 0x%08lx r26: 0x%08lx r27: 0x%08lx\n", 388 fp->exregs[8], fp->exregs[9], fp->exregs[10], fp->exregs[11]); 389 pr_info("r28: 0x%08lx r29: 0x%08lx r30: 0x%08lx tls: 0x%08lx\n", 390 fp->exregs[12], fp->exregs[13], fp->exregs[14], fp->tls); 391 pr_info(" hi: 0x%08lx lo: 0x%08lx\n", 392 fp->rhi, fp->rlo); 393 #else 394 pr_info(" r6: 0x%08lx r7: 0x%08lx r8: 0x%08lx r9: 0x%08lx\n", 395 fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]); 396 pr_info("r10: 0x%08lx r11: 0x%08lx r12: 0x%08lx r13: 0x%08lx\n", 397 fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]); 398 pr_info("r14: 0x%08lx r1: 0x%08lx\n", 399 fp->regs[8], fp->regs[9]); 400 #endif 401 402 return; 403 } 404