1 /* 2 * Ptrace user space interface. 3 * 4 * Copyright IBM Corp. 1999, 2010 5 * Author(s): Denis Joseph Barrow 6 * Martin Schwidefsky (schwidefsky@de.ibm.com) 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/sched.h> 11 #include <linux/mm.h> 12 #include <linux/smp.h> 13 #include <linux/errno.h> 14 #include <linux/ptrace.h> 15 #include <linux/user.h> 16 #include <linux/security.h> 17 #include <linux/audit.h> 18 #include <linux/signal.h> 19 #include <linux/elf.h> 20 #include <linux/regset.h> 21 #include <linux/tracehook.h> 22 #include <linux/seccomp.h> 23 #include <linux/compat.h> 24 #include <trace/syscall.h> 25 #include <asm/segment.h> 26 #include <asm/page.h> 27 #include <asm/pgtable.h> 28 #include <asm/pgalloc.h> 29 #include <asm/uaccess.h> 30 #include <asm/unistd.h> 31 #include <asm/switch_to.h> 32 #include "entry.h" 33 34 #ifdef CONFIG_COMPAT 35 #include "compat_ptrace.h" 36 #endif 37 38 #define CREATE_TRACE_POINTS 39 #include <trace/events/syscalls.h> 40 41 enum s390_regset { 42 REGSET_GENERAL, 43 REGSET_FP, 44 REGSET_LAST_BREAK, 45 REGSET_SYSTEM_CALL, 46 REGSET_GENERAL_EXTENDED, 47 }; 48 49 void update_per_regs(struct task_struct *task) 50 { 51 struct pt_regs *regs = task_pt_regs(task); 52 struct thread_struct *thread = &task->thread; 53 struct per_regs old, new; 54 55 /* Copy user specified PER registers */ 56 new.control = thread->per_user.control; 57 new.start = thread->per_user.start; 58 new.end = thread->per_user.end; 59 60 /* merge TIF_SINGLE_STEP into user specified PER registers. */ 61 if (test_tsk_thread_flag(task, TIF_SINGLE_STEP)) { 62 new.control |= PER_EVENT_IFETCH; 63 new.start = 0; 64 new.end = PSW_ADDR_INSN; 65 } 66 67 /* Take care of the PER enablement bit in the PSW. */ 68 if (!(new.control & PER_EVENT_MASK)) { 69 regs->psw.mask &= ~PSW_MASK_PER; 70 return; 71 } 72 regs->psw.mask |= PSW_MASK_PER; 73 __ctl_store(old, 9, 11); 74 if (memcmp(&new, &old, sizeof(struct per_regs)) != 0) 75 __ctl_load(new, 9, 11); 76 } 77 78 void user_enable_single_step(struct task_struct *task) 79 { 80 set_tsk_thread_flag(task, TIF_SINGLE_STEP); 81 if (task == current) 82 update_per_regs(task); 83 } 84 85 void user_disable_single_step(struct task_struct *task) 86 { 87 clear_tsk_thread_flag(task, TIF_SINGLE_STEP); 88 if (task == current) 89 update_per_regs(task); 90 } 91 92 /* 93 * Called by kernel/ptrace.c when detaching.. 94 * 95 * Clear all debugging related fields. 96 */ 97 void ptrace_disable(struct task_struct *task) 98 { 99 memset(&task->thread.per_user, 0, sizeof(task->thread.per_user)); 100 memset(&task->thread.per_event, 0, sizeof(task->thread.per_event)); 101 clear_tsk_thread_flag(task, TIF_SINGLE_STEP); 102 clear_tsk_thread_flag(task, TIF_PER_TRAP); 103 } 104 105 #ifndef CONFIG_64BIT 106 # define __ADDR_MASK 3 107 #else 108 # define __ADDR_MASK 7 109 #endif 110 111 static inline unsigned long __peek_user_per(struct task_struct *child, 112 addr_t addr) 113 { 114 struct per_struct_kernel *dummy = NULL; 115 116 if (addr == (addr_t) &dummy->cr9) 117 /* Control bits of the active per set. */ 118 return test_thread_flag(TIF_SINGLE_STEP) ? 119 PER_EVENT_IFETCH : child->thread.per_user.control; 120 else if (addr == (addr_t) &dummy->cr10) 121 /* Start address of the active per set. */ 122 return test_thread_flag(TIF_SINGLE_STEP) ? 123 0 : child->thread.per_user.start; 124 else if (addr == (addr_t) &dummy->cr11) 125 /* End address of the active per set. */ 126 return test_thread_flag(TIF_SINGLE_STEP) ? 127 PSW_ADDR_INSN : child->thread.per_user.end; 128 else if (addr == (addr_t) &dummy->bits) 129 /* Single-step bit. */ 130 return test_thread_flag(TIF_SINGLE_STEP) ? 131 (1UL << (BITS_PER_LONG - 1)) : 0; 132 else if (addr == (addr_t) &dummy->starting_addr) 133 /* Start address of the user specified per set. */ 134 return child->thread.per_user.start; 135 else if (addr == (addr_t) &dummy->ending_addr) 136 /* End address of the user specified per set. */ 137 return child->thread.per_user.end; 138 else if (addr == (addr_t) &dummy->perc_atmid) 139 /* PER code, ATMID and AI of the last PER trap */ 140 return (unsigned long) 141 child->thread.per_event.cause << (BITS_PER_LONG - 16); 142 else if (addr == (addr_t) &dummy->address) 143 /* Address of the last PER trap */ 144 return child->thread.per_event.address; 145 else if (addr == (addr_t) &dummy->access_id) 146 /* Access id of the last PER trap */ 147 return (unsigned long) 148 child->thread.per_event.paid << (BITS_PER_LONG - 8); 149 return 0; 150 } 151 152 /* 153 * Read the word at offset addr from the user area of a process. The 154 * trouble here is that the information is littered over different 155 * locations. The process registers are found on the kernel stack, 156 * the floating point stuff and the trace settings are stored in 157 * the task structure. In addition the different structures in 158 * struct user contain pad bytes that should be read as zeroes. 159 * Lovely... 160 */ 161 static unsigned long __peek_user(struct task_struct *child, addr_t addr) 162 { 163 struct user *dummy = NULL; 164 addr_t offset, tmp; 165 166 if (addr < (addr_t) &dummy->regs.acrs) { 167 /* 168 * psw and gprs are stored on the stack 169 */ 170 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr); 171 if (addr == (addr_t) &dummy->regs.psw.mask) 172 /* Return a clean psw mask. */ 173 tmp = psw_user_bits | (tmp & PSW_MASK_USER); 174 175 } else if (addr < (addr_t) &dummy->regs.orig_gpr2) { 176 /* 177 * access registers are stored in the thread structure 178 */ 179 offset = addr - (addr_t) &dummy->regs.acrs; 180 #ifdef CONFIG_64BIT 181 /* 182 * Very special case: old & broken 64 bit gdb reading 183 * from acrs[15]. Result is a 64 bit value. Read the 184 * 32 bit acrs[15] value and shift it by 32. Sick... 185 */ 186 if (addr == (addr_t) &dummy->regs.acrs[15]) 187 tmp = ((unsigned long) child->thread.acrs[15]) << 32; 188 else 189 #endif 190 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset); 191 192 } else if (addr == (addr_t) &dummy->regs.orig_gpr2) { 193 /* 194 * orig_gpr2 is stored on the kernel stack 195 */ 196 tmp = (addr_t) task_pt_regs(child)->orig_gpr2; 197 198 } else if (addr < (addr_t) &dummy->regs.fp_regs) { 199 /* 200 * prevent reads of padding hole between 201 * orig_gpr2 and fp_regs on s390. 202 */ 203 tmp = 0; 204 205 } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) { 206 /* 207 * floating point regs. are stored in the thread structure 208 */ 209 offset = addr - (addr_t) &dummy->regs.fp_regs; 210 tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset); 211 if (addr == (addr_t) &dummy->regs.fp_regs.fpc) 212 tmp &= (unsigned long) FPC_VALID_MASK 213 << (BITS_PER_LONG - 32); 214 215 } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) { 216 /* 217 * Handle access to the per_info structure. 218 */ 219 addr -= (addr_t) &dummy->regs.per_info; 220 tmp = __peek_user_per(child, addr); 221 222 } else 223 tmp = 0; 224 225 return tmp; 226 } 227 228 static int 229 peek_user(struct task_struct *child, addr_t addr, addr_t data) 230 { 231 addr_t tmp, mask; 232 233 /* 234 * Stupid gdb peeks/pokes the access registers in 64 bit with 235 * an alignment of 4. Programmers from hell... 236 */ 237 mask = __ADDR_MASK; 238 #ifdef CONFIG_64BIT 239 if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs && 240 addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2) 241 mask = 3; 242 #endif 243 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK) 244 return -EIO; 245 246 tmp = __peek_user(child, addr); 247 return put_user(tmp, (addr_t __user *) data); 248 } 249 250 static inline void __poke_user_per(struct task_struct *child, 251 addr_t addr, addr_t data) 252 { 253 struct per_struct_kernel *dummy = NULL; 254 255 /* 256 * There are only three fields in the per_info struct that the 257 * debugger user can write to. 258 * 1) cr9: the debugger wants to set a new PER event mask 259 * 2) starting_addr: the debugger wants to set a new starting 260 * address to use with the PER event mask. 261 * 3) ending_addr: the debugger wants to set a new ending 262 * address to use with the PER event mask. 263 * The user specified PER event mask and the start and end 264 * addresses are used only if single stepping is not in effect. 265 * Writes to any other field in per_info are ignored. 266 */ 267 if (addr == (addr_t) &dummy->cr9) 268 /* PER event mask of the user specified per set. */ 269 child->thread.per_user.control = 270 data & (PER_EVENT_MASK | PER_CONTROL_MASK); 271 else if (addr == (addr_t) &dummy->starting_addr) 272 /* Starting address of the user specified per set. */ 273 child->thread.per_user.start = data; 274 else if (addr == (addr_t) &dummy->ending_addr) 275 /* Ending address of the user specified per set. */ 276 child->thread.per_user.end = data; 277 } 278 279 /* 280 * Write a word to the user area of a process at location addr. This 281 * operation does have an additional problem compared to peek_user. 282 * Stores to the program status word and on the floating point 283 * control register needs to get checked for validity. 284 */ 285 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data) 286 { 287 struct user *dummy = NULL; 288 addr_t offset; 289 290 if (addr < (addr_t) &dummy->regs.acrs) { 291 /* 292 * psw and gprs are stored on the stack 293 */ 294 if (addr == (addr_t) &dummy->regs.psw.mask && 295 ((data & ~PSW_MASK_USER) != psw_user_bits || 296 ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA)))) 297 /* Invalid psw mask. */ 298 return -EINVAL; 299 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data; 300 301 } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) { 302 /* 303 * access registers are stored in the thread structure 304 */ 305 offset = addr - (addr_t) &dummy->regs.acrs; 306 #ifdef CONFIG_64BIT 307 /* 308 * Very special case: old & broken 64 bit gdb writing 309 * to acrs[15] with a 64 bit value. Ignore the lower 310 * half of the value and write the upper 32 bit to 311 * acrs[15]. Sick... 312 */ 313 if (addr == (addr_t) &dummy->regs.acrs[15]) 314 child->thread.acrs[15] = (unsigned int) (data >> 32); 315 else 316 #endif 317 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data; 318 319 } else if (addr == (addr_t) &dummy->regs.orig_gpr2) { 320 /* 321 * orig_gpr2 is stored on the kernel stack 322 */ 323 task_pt_regs(child)->orig_gpr2 = data; 324 325 } else if (addr < (addr_t) &dummy->regs.fp_regs) { 326 /* 327 * prevent writes of padding hole between 328 * orig_gpr2 and fp_regs on s390. 329 */ 330 return 0; 331 332 } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) { 333 /* 334 * floating point regs. are stored in the thread structure 335 */ 336 if (addr == (addr_t) &dummy->regs.fp_regs.fpc && 337 (data & ~((unsigned long) FPC_VALID_MASK 338 << (BITS_PER_LONG - 32))) != 0) 339 return -EINVAL; 340 offset = addr - (addr_t) &dummy->regs.fp_regs; 341 *(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data; 342 343 } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) { 344 /* 345 * Handle access to the per_info structure. 346 */ 347 addr -= (addr_t) &dummy->regs.per_info; 348 __poke_user_per(child, addr, data); 349 350 } 351 352 return 0; 353 } 354 355 static int poke_user(struct task_struct *child, addr_t addr, addr_t data) 356 { 357 addr_t mask; 358 359 /* 360 * Stupid gdb peeks/pokes the access registers in 64 bit with 361 * an alignment of 4. Programmers from hell indeed... 362 */ 363 mask = __ADDR_MASK; 364 #ifdef CONFIG_64BIT 365 if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs && 366 addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2) 367 mask = 3; 368 #endif 369 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK) 370 return -EIO; 371 372 return __poke_user(child, addr, data); 373 } 374 375 long arch_ptrace(struct task_struct *child, long request, 376 unsigned long addr, unsigned long data) 377 { 378 ptrace_area parea; 379 int copied, ret; 380 381 switch (request) { 382 case PTRACE_PEEKUSR: 383 /* read the word at location addr in the USER area. */ 384 return peek_user(child, addr, data); 385 386 case PTRACE_POKEUSR: 387 /* write the word at location addr in the USER area */ 388 return poke_user(child, addr, data); 389 390 case PTRACE_PEEKUSR_AREA: 391 case PTRACE_POKEUSR_AREA: 392 if (copy_from_user(&parea, (void __force __user *) addr, 393 sizeof(parea))) 394 return -EFAULT; 395 addr = parea.kernel_addr; 396 data = parea.process_addr; 397 copied = 0; 398 while (copied < parea.len) { 399 if (request == PTRACE_PEEKUSR_AREA) 400 ret = peek_user(child, addr, data); 401 else { 402 addr_t utmp; 403 if (get_user(utmp, 404 (addr_t __force __user *) data)) 405 return -EFAULT; 406 ret = poke_user(child, addr, utmp); 407 } 408 if (ret) 409 return ret; 410 addr += sizeof(unsigned long); 411 data += sizeof(unsigned long); 412 copied += sizeof(unsigned long); 413 } 414 return 0; 415 case PTRACE_GET_LAST_BREAK: 416 put_user(task_thread_info(child)->last_break, 417 (unsigned long __user *) data); 418 return 0; 419 default: 420 /* Removing high order bit from addr (only for 31 bit). */ 421 addr &= PSW_ADDR_INSN; 422 return ptrace_request(child, request, addr, data); 423 } 424 } 425 426 #ifdef CONFIG_COMPAT 427 /* 428 * Now the fun part starts... a 31 bit program running in the 429 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT, 430 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy 431 * to handle, the difference to the 64 bit versions of the requests 432 * is that the access is done in multiples of 4 byte instead of 433 * 8 bytes (sizeof(unsigned long) on 31/64 bit). 434 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA, 435 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program 436 * is a 31 bit program too, the content of struct user can be 437 * emulated. A 31 bit program peeking into the struct user of 438 * a 64 bit program is a no-no. 439 */ 440 441 /* 442 * Same as peek_user_per but for a 31 bit program. 443 */ 444 static inline __u32 __peek_user_per_compat(struct task_struct *child, 445 addr_t addr) 446 { 447 struct compat_per_struct_kernel *dummy32 = NULL; 448 449 if (addr == (addr_t) &dummy32->cr9) 450 /* Control bits of the active per set. */ 451 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ? 452 PER_EVENT_IFETCH : child->thread.per_user.control; 453 else if (addr == (addr_t) &dummy32->cr10) 454 /* Start address of the active per set. */ 455 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ? 456 0 : child->thread.per_user.start; 457 else if (addr == (addr_t) &dummy32->cr11) 458 /* End address of the active per set. */ 459 return test_thread_flag(TIF_SINGLE_STEP) ? 460 PSW32_ADDR_INSN : child->thread.per_user.end; 461 else if (addr == (addr_t) &dummy32->bits) 462 /* Single-step bit. */ 463 return (__u32) test_thread_flag(TIF_SINGLE_STEP) ? 464 0x80000000 : 0; 465 else if (addr == (addr_t) &dummy32->starting_addr) 466 /* Start address of the user specified per set. */ 467 return (__u32) child->thread.per_user.start; 468 else if (addr == (addr_t) &dummy32->ending_addr) 469 /* End address of the user specified per set. */ 470 return (__u32) child->thread.per_user.end; 471 else if (addr == (addr_t) &dummy32->perc_atmid) 472 /* PER code, ATMID and AI of the last PER trap */ 473 return (__u32) child->thread.per_event.cause << 16; 474 else if (addr == (addr_t) &dummy32->address) 475 /* Address of the last PER trap */ 476 return (__u32) child->thread.per_event.address; 477 else if (addr == (addr_t) &dummy32->access_id) 478 /* Access id of the last PER trap */ 479 return (__u32) child->thread.per_event.paid << 24; 480 return 0; 481 } 482 483 /* 484 * Same as peek_user but for a 31 bit program. 485 */ 486 static u32 __peek_user_compat(struct task_struct *child, addr_t addr) 487 { 488 struct compat_user *dummy32 = NULL; 489 addr_t offset; 490 __u32 tmp; 491 492 if (addr < (addr_t) &dummy32->regs.acrs) { 493 struct pt_regs *regs = task_pt_regs(child); 494 /* 495 * psw and gprs are stored on the stack 496 */ 497 if (addr == (addr_t) &dummy32->regs.psw.mask) { 498 /* Fake a 31 bit psw mask. */ 499 tmp = (__u32)(regs->psw.mask >> 32); 500 tmp = psw32_user_bits | (tmp & PSW32_MASK_USER); 501 } else if (addr == (addr_t) &dummy32->regs.psw.addr) { 502 /* Fake a 31 bit psw address. */ 503 tmp = (__u32) regs->psw.addr | 504 (__u32)(regs->psw.mask & PSW_MASK_BA); 505 } else { 506 /* gpr 0-15 */ 507 tmp = *(__u32 *)((addr_t) ®s->psw + addr*2 + 4); 508 } 509 } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) { 510 /* 511 * access registers are stored in the thread structure 512 */ 513 offset = addr - (addr_t) &dummy32->regs.acrs; 514 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset); 515 516 } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) { 517 /* 518 * orig_gpr2 is stored on the kernel stack 519 */ 520 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4); 521 522 } else if (addr < (addr_t) &dummy32->regs.fp_regs) { 523 /* 524 * prevent reads of padding hole between 525 * orig_gpr2 and fp_regs on s390. 526 */ 527 tmp = 0; 528 529 } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) { 530 /* 531 * floating point regs. are stored in the thread structure 532 */ 533 offset = addr - (addr_t) &dummy32->regs.fp_regs; 534 tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset); 535 536 } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) { 537 /* 538 * Handle access to the per_info structure. 539 */ 540 addr -= (addr_t) &dummy32->regs.per_info; 541 tmp = __peek_user_per_compat(child, addr); 542 543 } else 544 tmp = 0; 545 546 return tmp; 547 } 548 549 static int peek_user_compat(struct task_struct *child, 550 addr_t addr, addr_t data) 551 { 552 __u32 tmp; 553 554 if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3) 555 return -EIO; 556 557 tmp = __peek_user_compat(child, addr); 558 return put_user(tmp, (__u32 __user *) data); 559 } 560 561 /* 562 * Same as poke_user_per but for a 31 bit program. 563 */ 564 static inline void __poke_user_per_compat(struct task_struct *child, 565 addr_t addr, __u32 data) 566 { 567 struct compat_per_struct_kernel *dummy32 = NULL; 568 569 if (addr == (addr_t) &dummy32->cr9) 570 /* PER event mask of the user specified per set. */ 571 child->thread.per_user.control = 572 data & (PER_EVENT_MASK | PER_CONTROL_MASK); 573 else if (addr == (addr_t) &dummy32->starting_addr) 574 /* Starting address of the user specified per set. */ 575 child->thread.per_user.start = data; 576 else if (addr == (addr_t) &dummy32->ending_addr) 577 /* Ending address of the user specified per set. */ 578 child->thread.per_user.end = data; 579 } 580 581 /* 582 * Same as poke_user but for a 31 bit program. 583 */ 584 static int __poke_user_compat(struct task_struct *child, 585 addr_t addr, addr_t data) 586 { 587 struct compat_user *dummy32 = NULL; 588 __u32 tmp = (__u32) data; 589 addr_t offset; 590 591 if (addr < (addr_t) &dummy32->regs.acrs) { 592 struct pt_regs *regs = task_pt_regs(child); 593 /* 594 * psw, gprs, acrs and orig_gpr2 are stored on the stack 595 */ 596 if (addr == (addr_t) &dummy32->regs.psw.mask) { 597 /* Build a 64 bit psw mask from 31 bit mask. */ 598 if ((tmp & ~PSW32_MASK_USER) != psw32_user_bits) 599 /* Invalid psw mask. */ 600 return -EINVAL; 601 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) | 602 (regs->psw.mask & PSW_MASK_BA) | 603 (__u64)(tmp & PSW32_MASK_USER) << 32; 604 } else if (addr == (addr_t) &dummy32->regs.psw.addr) { 605 /* Build a 64 bit psw address from 31 bit address. */ 606 regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN; 607 /* Transfer 31 bit amode bit to psw mask. */ 608 regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) | 609 (__u64)(tmp & PSW32_ADDR_AMODE); 610 } else { 611 /* gpr 0-15 */ 612 *(__u32*)((addr_t) ®s->psw + addr*2 + 4) = tmp; 613 } 614 } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) { 615 /* 616 * access registers are stored in the thread structure 617 */ 618 offset = addr - (addr_t) &dummy32->regs.acrs; 619 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp; 620 621 } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) { 622 /* 623 * orig_gpr2 is stored on the kernel stack 624 */ 625 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp; 626 627 } else if (addr < (addr_t) &dummy32->regs.fp_regs) { 628 /* 629 * prevent writess of padding hole between 630 * orig_gpr2 and fp_regs on s390. 631 */ 632 return 0; 633 634 } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) { 635 /* 636 * floating point regs. are stored in the thread structure 637 */ 638 if (addr == (addr_t) &dummy32->regs.fp_regs.fpc && 639 (tmp & ~FPC_VALID_MASK) != 0) 640 /* Invalid floating point control. */ 641 return -EINVAL; 642 offset = addr - (addr_t) &dummy32->regs.fp_regs; 643 *(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp; 644 645 } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) { 646 /* 647 * Handle access to the per_info structure. 648 */ 649 addr -= (addr_t) &dummy32->regs.per_info; 650 __poke_user_per_compat(child, addr, data); 651 } 652 653 return 0; 654 } 655 656 static int poke_user_compat(struct task_struct *child, 657 addr_t addr, addr_t data) 658 { 659 if (!is_compat_task() || (addr & 3) || 660 addr > sizeof(struct compat_user) - 3) 661 return -EIO; 662 663 return __poke_user_compat(child, addr, data); 664 } 665 666 long compat_arch_ptrace(struct task_struct *child, compat_long_t request, 667 compat_ulong_t caddr, compat_ulong_t cdata) 668 { 669 unsigned long addr = caddr; 670 unsigned long data = cdata; 671 compat_ptrace_area parea; 672 int copied, ret; 673 674 switch (request) { 675 case PTRACE_PEEKUSR: 676 /* read the word at location addr in the USER area. */ 677 return peek_user_compat(child, addr, data); 678 679 case PTRACE_POKEUSR: 680 /* write the word at location addr in the USER area */ 681 return poke_user_compat(child, addr, data); 682 683 case PTRACE_PEEKUSR_AREA: 684 case PTRACE_POKEUSR_AREA: 685 if (copy_from_user(&parea, (void __force __user *) addr, 686 sizeof(parea))) 687 return -EFAULT; 688 addr = parea.kernel_addr; 689 data = parea.process_addr; 690 copied = 0; 691 while (copied < parea.len) { 692 if (request == PTRACE_PEEKUSR_AREA) 693 ret = peek_user_compat(child, addr, data); 694 else { 695 __u32 utmp; 696 if (get_user(utmp, 697 (__u32 __force __user *) data)) 698 return -EFAULT; 699 ret = poke_user_compat(child, addr, utmp); 700 } 701 if (ret) 702 return ret; 703 addr += sizeof(unsigned int); 704 data += sizeof(unsigned int); 705 copied += sizeof(unsigned int); 706 } 707 return 0; 708 case PTRACE_GET_LAST_BREAK: 709 put_user(task_thread_info(child)->last_break, 710 (unsigned int __user *) data); 711 return 0; 712 } 713 return compat_ptrace_request(child, request, addr, data); 714 } 715 #endif 716 717 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) 718 { 719 long ret = 0; 720 721 /* Do the secure computing check first. */ 722 if (secure_computing(regs->gprs[2])) { 723 /* seccomp failures shouldn't expose any additional code. */ 724 ret = -1; 725 goto out; 726 } 727 728 /* 729 * The sysc_tracesys code in entry.S stored the system 730 * call number to gprs[2]. 731 */ 732 if (test_thread_flag(TIF_SYSCALL_TRACE) && 733 (tracehook_report_syscall_entry(regs) || 734 regs->gprs[2] >= NR_syscalls)) { 735 /* 736 * Tracing decided this syscall should not happen or the 737 * debugger stored an invalid system call number. Skip 738 * the system call and the system call restart handling. 739 */ 740 clear_thread_flag(TIF_SYSCALL); 741 ret = -1; 742 } 743 744 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) 745 trace_sys_enter(regs, regs->gprs[2]); 746 747 audit_syscall_entry(is_compat_task() ? 748 AUDIT_ARCH_S390 : AUDIT_ARCH_S390X, 749 regs->gprs[2], regs->orig_gpr2, 750 regs->gprs[3], regs->gprs[4], 751 regs->gprs[5]); 752 out: 753 return ret ?: regs->gprs[2]; 754 } 755 756 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs) 757 { 758 audit_syscall_exit(regs); 759 760 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) 761 trace_sys_exit(regs, regs->gprs[2]); 762 763 if (test_thread_flag(TIF_SYSCALL_TRACE)) 764 tracehook_report_syscall_exit(regs, 0); 765 } 766 767 /* 768 * user_regset definitions. 769 */ 770 771 static int s390_regs_get(struct task_struct *target, 772 const struct user_regset *regset, 773 unsigned int pos, unsigned int count, 774 void *kbuf, void __user *ubuf) 775 { 776 if (target == current) 777 save_access_regs(target->thread.acrs); 778 779 if (kbuf) { 780 unsigned long *k = kbuf; 781 while (count > 0) { 782 *k++ = __peek_user(target, pos); 783 count -= sizeof(*k); 784 pos += sizeof(*k); 785 } 786 } else { 787 unsigned long __user *u = ubuf; 788 while (count > 0) { 789 if (__put_user(__peek_user(target, pos), u++)) 790 return -EFAULT; 791 count -= sizeof(*u); 792 pos += sizeof(*u); 793 } 794 } 795 return 0; 796 } 797 798 static int s390_regs_set(struct task_struct *target, 799 const struct user_regset *regset, 800 unsigned int pos, unsigned int count, 801 const void *kbuf, const void __user *ubuf) 802 { 803 int rc = 0; 804 805 if (target == current) 806 save_access_regs(target->thread.acrs); 807 808 if (kbuf) { 809 const unsigned long *k = kbuf; 810 while (count > 0 && !rc) { 811 rc = __poke_user(target, pos, *k++); 812 count -= sizeof(*k); 813 pos += sizeof(*k); 814 } 815 } else { 816 const unsigned long __user *u = ubuf; 817 while (count > 0 && !rc) { 818 unsigned long word; 819 rc = __get_user(word, u++); 820 if (rc) 821 break; 822 rc = __poke_user(target, pos, word); 823 count -= sizeof(*u); 824 pos += sizeof(*u); 825 } 826 } 827 828 if (rc == 0 && target == current) 829 restore_access_regs(target->thread.acrs); 830 831 return rc; 832 } 833 834 static int s390_fpregs_get(struct task_struct *target, 835 const struct user_regset *regset, unsigned int pos, 836 unsigned int count, void *kbuf, void __user *ubuf) 837 { 838 if (target == current) 839 save_fp_regs(&target->thread.fp_regs); 840 841 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, 842 &target->thread.fp_regs, 0, -1); 843 } 844 845 static int s390_fpregs_set(struct task_struct *target, 846 const struct user_regset *regset, unsigned int pos, 847 unsigned int count, const void *kbuf, 848 const void __user *ubuf) 849 { 850 int rc = 0; 851 852 if (target == current) 853 save_fp_regs(&target->thread.fp_regs); 854 855 /* If setting FPC, must validate it first. */ 856 if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) { 857 u32 fpc[2] = { target->thread.fp_regs.fpc, 0 }; 858 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc, 859 0, offsetof(s390_fp_regs, fprs)); 860 if (rc) 861 return rc; 862 if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0) 863 return -EINVAL; 864 target->thread.fp_regs.fpc = fpc[0]; 865 } 866 867 if (rc == 0 && count > 0) 868 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, 869 target->thread.fp_regs.fprs, 870 offsetof(s390_fp_regs, fprs), -1); 871 872 if (rc == 0 && target == current) 873 restore_fp_regs(&target->thread.fp_regs); 874 875 return rc; 876 } 877 878 #ifdef CONFIG_64BIT 879 880 static int s390_last_break_get(struct task_struct *target, 881 const struct user_regset *regset, 882 unsigned int pos, unsigned int count, 883 void *kbuf, void __user *ubuf) 884 { 885 if (count > 0) { 886 if (kbuf) { 887 unsigned long *k = kbuf; 888 *k = task_thread_info(target)->last_break; 889 } else { 890 unsigned long __user *u = ubuf; 891 if (__put_user(task_thread_info(target)->last_break, u)) 892 return -EFAULT; 893 } 894 } 895 return 0; 896 } 897 898 static int s390_last_break_set(struct task_struct *target, 899 const struct user_regset *regset, 900 unsigned int pos, unsigned int count, 901 const void *kbuf, const void __user *ubuf) 902 { 903 return 0; 904 } 905 906 #endif 907 908 static int s390_system_call_get(struct task_struct *target, 909 const struct user_regset *regset, 910 unsigned int pos, unsigned int count, 911 void *kbuf, void __user *ubuf) 912 { 913 unsigned int *data = &task_thread_info(target)->system_call; 914 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, 915 data, 0, sizeof(unsigned int)); 916 } 917 918 static int s390_system_call_set(struct task_struct *target, 919 const struct user_regset *regset, 920 unsigned int pos, unsigned int count, 921 const void *kbuf, const void __user *ubuf) 922 { 923 unsigned int *data = &task_thread_info(target)->system_call; 924 return user_regset_copyin(&pos, &count, &kbuf, &ubuf, 925 data, 0, sizeof(unsigned int)); 926 } 927 928 static const struct user_regset s390_regsets[] = { 929 [REGSET_GENERAL] = { 930 .core_note_type = NT_PRSTATUS, 931 .n = sizeof(s390_regs) / sizeof(long), 932 .size = sizeof(long), 933 .align = sizeof(long), 934 .get = s390_regs_get, 935 .set = s390_regs_set, 936 }, 937 [REGSET_FP] = { 938 .core_note_type = NT_PRFPREG, 939 .n = sizeof(s390_fp_regs) / sizeof(long), 940 .size = sizeof(long), 941 .align = sizeof(long), 942 .get = s390_fpregs_get, 943 .set = s390_fpregs_set, 944 }, 945 #ifdef CONFIG_64BIT 946 [REGSET_LAST_BREAK] = { 947 .core_note_type = NT_S390_LAST_BREAK, 948 .n = 1, 949 .size = sizeof(long), 950 .align = sizeof(long), 951 .get = s390_last_break_get, 952 .set = s390_last_break_set, 953 }, 954 #endif 955 [REGSET_SYSTEM_CALL] = { 956 .core_note_type = NT_S390_SYSTEM_CALL, 957 .n = 1, 958 .size = sizeof(unsigned int), 959 .align = sizeof(unsigned int), 960 .get = s390_system_call_get, 961 .set = s390_system_call_set, 962 }, 963 }; 964 965 static const struct user_regset_view user_s390_view = { 966 .name = UTS_MACHINE, 967 .e_machine = EM_S390, 968 .regsets = s390_regsets, 969 .n = ARRAY_SIZE(s390_regsets) 970 }; 971 972 #ifdef CONFIG_COMPAT 973 static int s390_compat_regs_get(struct task_struct *target, 974 const struct user_regset *regset, 975 unsigned int pos, unsigned int count, 976 void *kbuf, void __user *ubuf) 977 { 978 if (target == current) 979 save_access_regs(target->thread.acrs); 980 981 if (kbuf) { 982 compat_ulong_t *k = kbuf; 983 while (count > 0) { 984 *k++ = __peek_user_compat(target, pos); 985 count -= sizeof(*k); 986 pos += sizeof(*k); 987 } 988 } else { 989 compat_ulong_t __user *u = ubuf; 990 while (count > 0) { 991 if (__put_user(__peek_user_compat(target, pos), u++)) 992 return -EFAULT; 993 count -= sizeof(*u); 994 pos += sizeof(*u); 995 } 996 } 997 return 0; 998 } 999 1000 static int s390_compat_regs_set(struct task_struct *target, 1001 const struct user_regset *regset, 1002 unsigned int pos, unsigned int count, 1003 const void *kbuf, const void __user *ubuf) 1004 { 1005 int rc = 0; 1006 1007 if (target == current) 1008 save_access_regs(target->thread.acrs); 1009 1010 if (kbuf) { 1011 const compat_ulong_t *k = kbuf; 1012 while (count > 0 && !rc) { 1013 rc = __poke_user_compat(target, pos, *k++); 1014 count -= sizeof(*k); 1015 pos += sizeof(*k); 1016 } 1017 } else { 1018 const compat_ulong_t __user *u = ubuf; 1019 while (count > 0 && !rc) { 1020 compat_ulong_t word; 1021 rc = __get_user(word, u++); 1022 if (rc) 1023 break; 1024 rc = __poke_user_compat(target, pos, word); 1025 count -= sizeof(*u); 1026 pos += sizeof(*u); 1027 } 1028 } 1029 1030 if (rc == 0 && target == current) 1031 restore_access_regs(target->thread.acrs); 1032 1033 return rc; 1034 } 1035 1036 static int s390_compat_regs_high_get(struct task_struct *target, 1037 const struct user_regset *regset, 1038 unsigned int pos, unsigned int count, 1039 void *kbuf, void __user *ubuf) 1040 { 1041 compat_ulong_t *gprs_high; 1042 1043 gprs_high = (compat_ulong_t *) 1044 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)]; 1045 if (kbuf) { 1046 compat_ulong_t *k = kbuf; 1047 while (count > 0) { 1048 *k++ = *gprs_high; 1049 gprs_high += 2; 1050 count -= sizeof(*k); 1051 } 1052 } else { 1053 compat_ulong_t __user *u = ubuf; 1054 while (count > 0) { 1055 if (__put_user(*gprs_high, u++)) 1056 return -EFAULT; 1057 gprs_high += 2; 1058 count -= sizeof(*u); 1059 } 1060 } 1061 return 0; 1062 } 1063 1064 static int s390_compat_regs_high_set(struct task_struct *target, 1065 const struct user_regset *regset, 1066 unsigned int pos, unsigned int count, 1067 const void *kbuf, const void __user *ubuf) 1068 { 1069 compat_ulong_t *gprs_high; 1070 int rc = 0; 1071 1072 gprs_high = (compat_ulong_t *) 1073 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)]; 1074 if (kbuf) { 1075 const compat_ulong_t *k = kbuf; 1076 while (count > 0) { 1077 *gprs_high = *k++; 1078 *gprs_high += 2; 1079 count -= sizeof(*k); 1080 } 1081 } else { 1082 const compat_ulong_t __user *u = ubuf; 1083 while (count > 0 && !rc) { 1084 unsigned long word; 1085 rc = __get_user(word, u++); 1086 if (rc) 1087 break; 1088 *gprs_high = word; 1089 *gprs_high += 2; 1090 count -= sizeof(*u); 1091 } 1092 } 1093 1094 return rc; 1095 } 1096 1097 static int s390_compat_last_break_get(struct task_struct *target, 1098 const struct user_regset *regset, 1099 unsigned int pos, unsigned int count, 1100 void *kbuf, void __user *ubuf) 1101 { 1102 compat_ulong_t last_break; 1103 1104 if (count > 0) { 1105 last_break = task_thread_info(target)->last_break; 1106 if (kbuf) { 1107 unsigned long *k = kbuf; 1108 *k = last_break; 1109 } else { 1110 unsigned long __user *u = ubuf; 1111 if (__put_user(last_break, u)) 1112 return -EFAULT; 1113 } 1114 } 1115 return 0; 1116 } 1117 1118 static int s390_compat_last_break_set(struct task_struct *target, 1119 const struct user_regset *regset, 1120 unsigned int pos, unsigned int count, 1121 const void *kbuf, const void __user *ubuf) 1122 { 1123 return 0; 1124 } 1125 1126 static const struct user_regset s390_compat_regsets[] = { 1127 [REGSET_GENERAL] = { 1128 .core_note_type = NT_PRSTATUS, 1129 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t), 1130 .size = sizeof(compat_long_t), 1131 .align = sizeof(compat_long_t), 1132 .get = s390_compat_regs_get, 1133 .set = s390_compat_regs_set, 1134 }, 1135 [REGSET_FP] = { 1136 .core_note_type = NT_PRFPREG, 1137 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t), 1138 .size = sizeof(compat_long_t), 1139 .align = sizeof(compat_long_t), 1140 .get = s390_fpregs_get, 1141 .set = s390_fpregs_set, 1142 }, 1143 [REGSET_LAST_BREAK] = { 1144 .core_note_type = NT_S390_LAST_BREAK, 1145 .n = 1, 1146 .size = sizeof(long), 1147 .align = sizeof(long), 1148 .get = s390_compat_last_break_get, 1149 .set = s390_compat_last_break_set, 1150 }, 1151 [REGSET_SYSTEM_CALL] = { 1152 .core_note_type = NT_S390_SYSTEM_CALL, 1153 .n = 1, 1154 .size = sizeof(compat_uint_t), 1155 .align = sizeof(compat_uint_t), 1156 .get = s390_system_call_get, 1157 .set = s390_system_call_set, 1158 }, 1159 [REGSET_GENERAL_EXTENDED] = { 1160 .core_note_type = NT_S390_HIGH_GPRS, 1161 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t), 1162 .size = sizeof(compat_long_t), 1163 .align = sizeof(compat_long_t), 1164 .get = s390_compat_regs_high_get, 1165 .set = s390_compat_regs_high_set, 1166 }, 1167 }; 1168 1169 static const struct user_regset_view user_s390_compat_view = { 1170 .name = "s390", 1171 .e_machine = EM_S390, 1172 .regsets = s390_compat_regsets, 1173 .n = ARRAY_SIZE(s390_compat_regsets) 1174 }; 1175 #endif 1176 1177 const struct user_regset_view *task_user_regset_view(struct task_struct *task) 1178 { 1179 #ifdef CONFIG_COMPAT 1180 if (test_tsk_thread_flag(task, TIF_31BIT)) 1181 return &user_s390_compat_view; 1182 #endif 1183 return &user_s390_view; 1184 } 1185 1186 static const char *gpr_names[NUM_GPRS] = { 1187 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", 1188 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15", 1189 }; 1190 1191 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset) 1192 { 1193 if (offset >= NUM_GPRS) 1194 return 0; 1195 return regs->gprs[offset]; 1196 } 1197 1198 int regs_query_register_offset(const char *name) 1199 { 1200 unsigned long offset; 1201 1202 if (!name || *name != 'r') 1203 return -EINVAL; 1204 if (strict_strtoul(name + 1, 10, &offset)) 1205 return -EINVAL; 1206 if (offset >= NUM_GPRS) 1207 return -EINVAL; 1208 return offset; 1209 } 1210 1211 const char *regs_query_register_name(unsigned int offset) 1212 { 1213 if (offset >= NUM_GPRS) 1214 return NULL; 1215 return gpr_names[offset]; 1216 } 1217 1218 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) 1219 { 1220 unsigned long ksp = kernel_stack_pointer(regs); 1221 1222 return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1)); 1223 } 1224 1225 /** 1226 * regs_get_kernel_stack_nth() - get Nth entry of the stack 1227 * @regs:pt_regs which contains kernel stack pointer. 1228 * @n:stack entry number. 1229 * 1230 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which 1231 * is specifined by @regs. If the @n th entry is NOT in the kernel stack, 1232 * this returns 0. 1233 */ 1234 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) 1235 { 1236 unsigned long addr; 1237 1238 addr = kernel_stack_pointer(regs) + n * sizeof(long); 1239 if (!regs_within_kernel_stack(regs, addr)) 1240 return 0; 1241 return *(unsigned long *)addr; 1242 } 1243