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