1 /* 2 * arch/s390/kernel/ptrace.c 3 * 4 * S390 version 5 * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation 6 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), 7 * Martin Schwidefsky (schwidefsky@de.ibm.com) 8 * 9 * Based on PowerPC version 10 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 11 * 12 * Derived from "arch/m68k/kernel/ptrace.c" 13 * Copyright (C) 1994 by Hamish Macdonald 14 * Taken from linux/kernel/ptrace.c and modified for M680x0. 15 * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds 16 * 17 * Modified by Cort Dougan (cort@cs.nmt.edu) 18 * 19 * 20 * This file is subject to the terms and conditions of the GNU General 21 * Public License. See the file README.legal in the main directory of 22 * this archive for more details. 23 */ 24 25 #include <linux/kernel.h> 26 #include <linux/sched.h> 27 #include <linux/mm.h> 28 #include <linux/smp.h> 29 #include <linux/errno.h> 30 #include <linux/ptrace.h> 31 #include <linux/user.h> 32 #include <linux/security.h> 33 #include <linux/audit.h> 34 #include <linux/signal.h> 35 #include <linux/elf.h> 36 #include <linux/regset.h> 37 #include <linux/tracehook.h> 38 #include <linux/seccomp.h> 39 #include <trace/syscall.h> 40 #include <asm/compat.h> 41 #include <asm/segment.h> 42 #include <asm/page.h> 43 #include <asm/pgtable.h> 44 #include <asm/pgalloc.h> 45 #include <asm/system.h> 46 #include <asm/uaccess.h> 47 #include <asm/unistd.h> 48 #include "entry.h" 49 50 #ifdef CONFIG_COMPAT 51 #include "compat_ptrace.h" 52 #endif 53 54 #define CREATE_TRACE_POINTS 55 #include <trace/events/syscalls.h> 56 57 enum s390_regset { 58 REGSET_GENERAL, 59 REGSET_FP, 60 REGSET_LAST_BREAK, 61 REGSET_GENERAL_EXTENDED, 62 }; 63 64 static void 65 FixPerRegisters(struct task_struct *task) 66 { 67 struct pt_regs *regs; 68 per_struct *per_info; 69 per_cr_words cr_words; 70 71 regs = task_pt_regs(task); 72 per_info = (per_struct *) &task->thread.per_info; 73 per_info->control_regs.bits.em_instruction_fetch = 74 per_info->single_step | per_info->instruction_fetch; 75 76 if (per_info->single_step) { 77 per_info->control_regs.bits.starting_addr = 0; 78 #ifdef CONFIG_COMPAT 79 if (is_compat_task()) 80 per_info->control_regs.bits.ending_addr = 0x7fffffffUL; 81 else 82 #endif 83 per_info->control_regs.bits.ending_addr = PSW_ADDR_INSN; 84 } else { 85 per_info->control_regs.bits.starting_addr = 86 per_info->starting_addr; 87 per_info->control_regs.bits.ending_addr = 88 per_info->ending_addr; 89 } 90 /* 91 * if any of the control reg tracing bits are on 92 * we switch on per in the psw 93 */ 94 if (per_info->control_regs.words.cr[0] & PER_EM_MASK) 95 regs->psw.mask |= PSW_MASK_PER; 96 else 97 regs->psw.mask &= ~PSW_MASK_PER; 98 99 if (per_info->control_regs.bits.em_storage_alteration) 100 per_info->control_regs.bits.storage_alt_space_ctl = 1; 101 else 102 per_info->control_regs.bits.storage_alt_space_ctl = 0; 103 104 if (task == current) { 105 __ctl_store(cr_words, 9, 11); 106 if (memcmp(&cr_words, &per_info->control_regs.words, 107 sizeof(cr_words)) != 0) 108 __ctl_load(per_info->control_regs.words, 9, 11); 109 } 110 } 111 112 void user_enable_single_step(struct task_struct *task) 113 { 114 task->thread.per_info.single_step = 1; 115 FixPerRegisters(task); 116 } 117 118 void user_disable_single_step(struct task_struct *task) 119 { 120 task->thread.per_info.single_step = 0; 121 FixPerRegisters(task); 122 } 123 124 /* 125 * Called by kernel/ptrace.c when detaching.. 126 * 127 * Make sure single step bits etc are not set. 128 */ 129 void 130 ptrace_disable(struct task_struct *child) 131 { 132 /* make sure the single step bit is not set. */ 133 user_disable_single_step(child); 134 } 135 136 #ifndef CONFIG_64BIT 137 # define __ADDR_MASK 3 138 #else 139 # define __ADDR_MASK 7 140 #endif 141 142 /* 143 * Read the word at offset addr from the user area of a process. The 144 * trouble here is that the information is littered over different 145 * locations. The process registers are found on the kernel stack, 146 * the floating point stuff and the trace settings are stored in 147 * the task structure. In addition the different structures in 148 * struct user contain pad bytes that should be read as zeroes. 149 * Lovely... 150 */ 151 static unsigned long __peek_user(struct task_struct *child, addr_t addr) 152 { 153 struct user *dummy = NULL; 154 addr_t offset, tmp; 155 156 if (addr < (addr_t) &dummy->regs.acrs) { 157 /* 158 * psw and gprs are stored on the stack 159 */ 160 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr); 161 if (addr == (addr_t) &dummy->regs.psw.mask) 162 /* Remove per bit from user psw. */ 163 tmp &= ~PSW_MASK_PER; 164 165 } else if (addr < (addr_t) &dummy->regs.orig_gpr2) { 166 /* 167 * access registers are stored in the thread structure 168 */ 169 offset = addr - (addr_t) &dummy->regs.acrs; 170 #ifdef CONFIG_64BIT 171 /* 172 * Very special case: old & broken 64 bit gdb reading 173 * from acrs[15]. Result is a 64 bit value. Read the 174 * 32 bit acrs[15] value and shift it by 32. Sick... 175 */ 176 if (addr == (addr_t) &dummy->regs.acrs[15]) 177 tmp = ((unsigned long) child->thread.acrs[15]) << 32; 178 else 179 #endif 180 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset); 181 182 } else if (addr == (addr_t) &dummy->regs.orig_gpr2) { 183 /* 184 * orig_gpr2 is stored on the kernel stack 185 */ 186 tmp = (addr_t) task_pt_regs(child)->orig_gpr2; 187 188 } else if (addr < (addr_t) &dummy->regs.fp_regs) { 189 /* 190 * prevent reads of padding hole between 191 * orig_gpr2 and fp_regs on s390. 192 */ 193 tmp = 0; 194 195 } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) { 196 /* 197 * floating point regs. are stored in the thread structure 198 */ 199 offset = addr - (addr_t) &dummy->regs.fp_regs; 200 tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset); 201 if (addr == (addr_t) &dummy->regs.fp_regs.fpc) 202 tmp &= (unsigned long) FPC_VALID_MASK 203 << (BITS_PER_LONG - 32); 204 205 } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) { 206 /* 207 * per_info is found in the thread structure 208 */ 209 offset = addr - (addr_t) &dummy->regs.per_info; 210 tmp = *(addr_t *)((addr_t) &child->thread.per_info + offset); 211 212 } else 213 tmp = 0; 214 215 return tmp; 216 } 217 218 static int 219 peek_user(struct task_struct *child, addr_t addr, addr_t data) 220 { 221 addr_t tmp, mask; 222 223 /* 224 * Stupid gdb peeks/pokes the access registers in 64 bit with 225 * an alignment of 4. Programmers from hell... 226 */ 227 mask = __ADDR_MASK; 228 #ifdef CONFIG_64BIT 229 if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs && 230 addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2) 231 mask = 3; 232 #endif 233 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK) 234 return -EIO; 235 236 tmp = __peek_user(child, addr); 237 return put_user(tmp, (addr_t __user *) data); 238 } 239 240 /* 241 * Write a word to the user area of a process at location addr. This 242 * operation does have an additional problem compared to peek_user. 243 * Stores to the program status word and on the floating point 244 * control register needs to get checked for validity. 245 */ 246 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data) 247 { 248 struct user *dummy = NULL; 249 addr_t offset; 250 251 if (addr < (addr_t) &dummy->regs.acrs) { 252 /* 253 * psw and gprs are stored on the stack 254 */ 255 if (addr == (addr_t) &dummy->regs.psw.mask && 256 #ifdef CONFIG_COMPAT 257 data != PSW_MASK_MERGE(psw_user32_bits, data) && 258 #endif 259 data != PSW_MASK_MERGE(psw_user_bits, data)) 260 /* Invalid psw mask. */ 261 return -EINVAL; 262 #ifndef CONFIG_64BIT 263 if (addr == (addr_t) &dummy->regs.psw.addr) 264 /* I'd like to reject addresses without the 265 high order bit but older gdb's rely on it */ 266 data |= PSW_ADDR_AMODE; 267 #endif 268 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data; 269 270 } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) { 271 /* 272 * access registers are stored in the thread structure 273 */ 274 offset = addr - (addr_t) &dummy->regs.acrs; 275 #ifdef CONFIG_64BIT 276 /* 277 * Very special case: old & broken 64 bit gdb writing 278 * to acrs[15] with a 64 bit value. Ignore the lower 279 * half of the value and write the upper 32 bit to 280 * acrs[15]. Sick... 281 */ 282 if (addr == (addr_t) &dummy->regs.acrs[15]) 283 child->thread.acrs[15] = (unsigned int) (data >> 32); 284 else 285 #endif 286 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data; 287 288 } else if (addr == (addr_t) &dummy->regs.orig_gpr2) { 289 /* 290 * orig_gpr2 is stored on the kernel stack 291 */ 292 task_pt_regs(child)->orig_gpr2 = data; 293 294 } else if (addr < (addr_t) &dummy->regs.fp_regs) { 295 /* 296 * prevent writes of padding hole between 297 * orig_gpr2 and fp_regs on s390. 298 */ 299 return 0; 300 301 } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) { 302 /* 303 * floating point regs. are stored in the thread structure 304 */ 305 if (addr == (addr_t) &dummy->regs.fp_regs.fpc && 306 (data & ~((unsigned long) FPC_VALID_MASK 307 << (BITS_PER_LONG - 32))) != 0) 308 return -EINVAL; 309 offset = addr - (addr_t) &dummy->regs.fp_regs; 310 *(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data; 311 312 } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) { 313 /* 314 * per_info is found in the thread structure 315 */ 316 offset = addr - (addr_t) &dummy->regs.per_info; 317 *(addr_t *)((addr_t) &child->thread.per_info + offset) = data; 318 319 } 320 321 FixPerRegisters(child); 322 return 0; 323 } 324 325 static int 326 poke_user(struct task_struct *child, addr_t addr, addr_t data) 327 { 328 addr_t mask; 329 330 /* 331 * Stupid gdb peeks/pokes the access registers in 64 bit with 332 * an alignment of 4. Programmers from hell indeed... 333 */ 334 mask = __ADDR_MASK; 335 #ifdef CONFIG_64BIT 336 if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs && 337 addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2) 338 mask = 3; 339 #endif 340 if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK) 341 return -EIO; 342 343 return __poke_user(child, addr, data); 344 } 345 346 long arch_ptrace(struct task_struct *child, long request, long addr, long data) 347 { 348 ptrace_area parea; 349 int copied, ret; 350 351 switch (request) { 352 case PTRACE_PEEKUSR: 353 /* read the word at location addr in the USER area. */ 354 return peek_user(child, addr, data); 355 356 case PTRACE_POKEUSR: 357 /* write the word at location addr in the USER area */ 358 return poke_user(child, addr, data); 359 360 case PTRACE_PEEKUSR_AREA: 361 case PTRACE_POKEUSR_AREA: 362 if (copy_from_user(&parea, (void __force __user *) addr, 363 sizeof(parea))) 364 return -EFAULT; 365 addr = parea.kernel_addr; 366 data = parea.process_addr; 367 copied = 0; 368 while (copied < parea.len) { 369 if (request == PTRACE_PEEKUSR_AREA) 370 ret = peek_user(child, addr, data); 371 else { 372 addr_t utmp; 373 if (get_user(utmp, 374 (addr_t __force __user *) data)) 375 return -EFAULT; 376 ret = poke_user(child, addr, utmp); 377 } 378 if (ret) 379 return ret; 380 addr += sizeof(unsigned long); 381 data += sizeof(unsigned long); 382 copied += sizeof(unsigned long); 383 } 384 return 0; 385 case PTRACE_GET_LAST_BREAK: 386 put_user(task_thread_info(child)->last_break, 387 (unsigned long __user *) data); 388 return 0; 389 default: 390 /* Removing high order bit from addr (only for 31 bit). */ 391 addr &= PSW_ADDR_INSN; 392 return ptrace_request(child, request, addr, data); 393 } 394 } 395 396 #ifdef CONFIG_COMPAT 397 /* 398 * Now the fun part starts... a 31 bit program running in the 399 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT, 400 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy 401 * to handle, the difference to the 64 bit versions of the requests 402 * is that the access is done in multiples of 4 byte instead of 403 * 8 bytes (sizeof(unsigned long) on 31/64 bit). 404 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA, 405 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program 406 * is a 31 bit program too, the content of struct user can be 407 * emulated. A 31 bit program peeking into the struct user of 408 * a 64 bit program is a no-no. 409 */ 410 411 /* 412 * Same as peek_user but for a 31 bit program. 413 */ 414 static u32 __peek_user_compat(struct task_struct *child, addr_t addr) 415 { 416 struct user32 *dummy32 = NULL; 417 per_struct32 *dummy_per32 = NULL; 418 addr_t offset; 419 __u32 tmp; 420 421 if (addr < (addr_t) &dummy32->regs.acrs) { 422 /* 423 * psw and gprs are stored on the stack 424 */ 425 if (addr == (addr_t) &dummy32->regs.psw.mask) { 426 /* Fake a 31 bit psw mask. */ 427 tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32); 428 tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp); 429 } else if (addr == (addr_t) &dummy32->regs.psw.addr) { 430 /* Fake a 31 bit psw address. */ 431 tmp = (__u32) task_pt_regs(child)->psw.addr | 432 PSW32_ADDR_AMODE31; 433 } else { 434 /* gpr 0-15 */ 435 tmp = *(__u32 *)((addr_t) &task_pt_regs(child)->psw + 436 addr*2 + 4); 437 } 438 } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) { 439 /* 440 * access registers are stored in the thread structure 441 */ 442 offset = addr - (addr_t) &dummy32->regs.acrs; 443 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset); 444 445 } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) { 446 /* 447 * orig_gpr2 is stored on the kernel stack 448 */ 449 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4); 450 451 } else if (addr < (addr_t) &dummy32->regs.fp_regs) { 452 /* 453 * prevent reads of padding hole between 454 * orig_gpr2 and fp_regs on s390. 455 */ 456 tmp = 0; 457 458 } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) { 459 /* 460 * floating point regs. are stored in the thread structure 461 */ 462 offset = addr - (addr_t) &dummy32->regs.fp_regs; 463 tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset); 464 465 } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) { 466 /* 467 * per_info is found in the thread structure 468 */ 469 offset = addr - (addr_t) &dummy32->regs.per_info; 470 /* This is magic. See per_struct and per_struct32. */ 471 if ((offset >= (addr_t) &dummy_per32->control_regs && 472 offset < (addr_t) (&dummy_per32->control_regs + 1)) || 473 (offset >= (addr_t) &dummy_per32->starting_addr && 474 offset <= (addr_t) &dummy_per32->ending_addr) || 475 offset == (addr_t) &dummy_per32->lowcore.words.address) 476 offset = offset*2 + 4; 477 else 478 offset = offset*2; 479 tmp = *(__u32 *)((addr_t) &child->thread.per_info + offset); 480 481 } else 482 tmp = 0; 483 484 return tmp; 485 } 486 487 static int peek_user_compat(struct task_struct *child, 488 addr_t addr, addr_t data) 489 { 490 __u32 tmp; 491 492 if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3) 493 return -EIO; 494 495 tmp = __peek_user_compat(child, addr); 496 return put_user(tmp, (__u32 __user *) data); 497 } 498 499 /* 500 * Same as poke_user but for a 31 bit program. 501 */ 502 static int __poke_user_compat(struct task_struct *child, 503 addr_t addr, addr_t data) 504 { 505 struct user32 *dummy32 = NULL; 506 per_struct32 *dummy_per32 = NULL; 507 __u32 tmp = (__u32) data; 508 addr_t offset; 509 510 if (addr < (addr_t) &dummy32->regs.acrs) { 511 /* 512 * psw, gprs, acrs and orig_gpr2 are stored on the stack 513 */ 514 if (addr == (addr_t) &dummy32->regs.psw.mask) { 515 /* Build a 64 bit psw mask from 31 bit mask. */ 516 if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp)) 517 /* Invalid psw mask. */ 518 return -EINVAL; 519 task_pt_regs(child)->psw.mask = 520 PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32); 521 } else if (addr == (addr_t) &dummy32->regs.psw.addr) { 522 /* Build a 64 bit psw address from 31 bit address. */ 523 task_pt_regs(child)->psw.addr = 524 (__u64) tmp & PSW32_ADDR_INSN; 525 } else { 526 /* gpr 0-15 */ 527 *(__u32*)((addr_t) &task_pt_regs(child)->psw 528 + addr*2 + 4) = tmp; 529 } 530 } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) { 531 /* 532 * access registers are stored in the thread structure 533 */ 534 offset = addr - (addr_t) &dummy32->regs.acrs; 535 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp; 536 537 } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) { 538 /* 539 * orig_gpr2 is stored on the kernel stack 540 */ 541 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp; 542 543 } else if (addr < (addr_t) &dummy32->regs.fp_regs) { 544 /* 545 * prevent writess of padding hole between 546 * orig_gpr2 and fp_regs on s390. 547 */ 548 return 0; 549 550 } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) { 551 /* 552 * floating point regs. are stored in the thread structure 553 */ 554 if (addr == (addr_t) &dummy32->regs.fp_regs.fpc && 555 (tmp & ~FPC_VALID_MASK) != 0) 556 /* Invalid floating point control. */ 557 return -EINVAL; 558 offset = addr - (addr_t) &dummy32->regs.fp_regs; 559 *(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp; 560 561 } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) { 562 /* 563 * per_info is found in the thread structure. 564 */ 565 offset = addr - (addr_t) &dummy32->regs.per_info; 566 /* 567 * This is magic. See per_struct and per_struct32. 568 * By incident the offsets in per_struct are exactly 569 * twice the offsets in per_struct32 for all fields. 570 * The 8 byte fields need special handling though, 571 * because the second half (bytes 4-7) is needed and 572 * not the first half. 573 */ 574 if ((offset >= (addr_t) &dummy_per32->control_regs && 575 offset < (addr_t) (&dummy_per32->control_regs + 1)) || 576 (offset >= (addr_t) &dummy_per32->starting_addr && 577 offset <= (addr_t) &dummy_per32->ending_addr) || 578 offset == (addr_t) &dummy_per32->lowcore.words.address) 579 offset = offset*2 + 4; 580 else 581 offset = offset*2; 582 *(__u32 *)((addr_t) &child->thread.per_info + offset) = tmp; 583 584 } 585 586 FixPerRegisters(child); 587 return 0; 588 } 589 590 static int poke_user_compat(struct task_struct *child, 591 addr_t addr, addr_t data) 592 { 593 if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user32) - 3) 594 return -EIO; 595 596 return __poke_user_compat(child, addr, data); 597 } 598 599 long compat_arch_ptrace(struct task_struct *child, compat_long_t request, 600 compat_ulong_t caddr, compat_ulong_t cdata) 601 { 602 unsigned long addr = caddr; 603 unsigned long data = cdata; 604 ptrace_area_emu31 parea; 605 int copied, ret; 606 607 switch (request) { 608 case PTRACE_PEEKUSR: 609 /* read the word at location addr in the USER area. */ 610 return peek_user_compat(child, addr, data); 611 612 case PTRACE_POKEUSR: 613 /* write the word at location addr in the USER area */ 614 return poke_user_compat(child, addr, data); 615 616 case PTRACE_PEEKUSR_AREA: 617 case PTRACE_POKEUSR_AREA: 618 if (copy_from_user(&parea, (void __force __user *) addr, 619 sizeof(parea))) 620 return -EFAULT; 621 addr = parea.kernel_addr; 622 data = parea.process_addr; 623 copied = 0; 624 while (copied < parea.len) { 625 if (request == PTRACE_PEEKUSR_AREA) 626 ret = peek_user_compat(child, addr, data); 627 else { 628 __u32 utmp; 629 if (get_user(utmp, 630 (__u32 __force __user *) data)) 631 return -EFAULT; 632 ret = poke_user_compat(child, addr, utmp); 633 } 634 if (ret) 635 return ret; 636 addr += sizeof(unsigned int); 637 data += sizeof(unsigned int); 638 copied += sizeof(unsigned int); 639 } 640 return 0; 641 case PTRACE_GET_LAST_BREAK: 642 put_user(task_thread_info(child)->last_break, 643 (unsigned int __user *) data); 644 return 0; 645 } 646 return compat_ptrace_request(child, request, addr, data); 647 } 648 #endif 649 650 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) 651 { 652 long ret = 0; 653 654 /* Do the secure computing check first. */ 655 secure_computing(regs->gprs[2]); 656 657 /* 658 * The sysc_tracesys code in entry.S stored the system 659 * call number to gprs[2]. 660 */ 661 if (test_thread_flag(TIF_SYSCALL_TRACE) && 662 (tracehook_report_syscall_entry(regs) || 663 regs->gprs[2] >= NR_syscalls)) { 664 /* 665 * Tracing decided this syscall should not happen or the 666 * debugger stored an invalid system call number. Skip 667 * the system call and the system call restart handling. 668 */ 669 regs->svcnr = 0; 670 ret = -1; 671 } 672 673 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) 674 trace_sys_enter(regs, regs->gprs[2]); 675 676 if (unlikely(current->audit_context)) 677 audit_syscall_entry(is_compat_task() ? 678 AUDIT_ARCH_S390 : AUDIT_ARCH_S390X, 679 regs->gprs[2], regs->orig_gpr2, 680 regs->gprs[3], regs->gprs[4], 681 regs->gprs[5]); 682 return ret ?: regs->gprs[2]; 683 } 684 685 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs) 686 { 687 if (unlikely(current->audit_context)) 688 audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]), 689 regs->gprs[2]); 690 691 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) 692 trace_sys_exit(regs, regs->gprs[2]); 693 694 if (test_thread_flag(TIF_SYSCALL_TRACE)) 695 tracehook_report_syscall_exit(regs, 0); 696 } 697 698 /* 699 * user_regset definitions. 700 */ 701 702 static int s390_regs_get(struct task_struct *target, 703 const struct user_regset *regset, 704 unsigned int pos, unsigned int count, 705 void *kbuf, void __user *ubuf) 706 { 707 if (target == current) 708 save_access_regs(target->thread.acrs); 709 710 if (kbuf) { 711 unsigned long *k = kbuf; 712 while (count > 0) { 713 *k++ = __peek_user(target, pos); 714 count -= sizeof(*k); 715 pos += sizeof(*k); 716 } 717 } else { 718 unsigned long __user *u = ubuf; 719 while (count > 0) { 720 if (__put_user(__peek_user(target, pos), u++)) 721 return -EFAULT; 722 count -= sizeof(*u); 723 pos += sizeof(*u); 724 } 725 } 726 return 0; 727 } 728 729 static int s390_regs_set(struct task_struct *target, 730 const struct user_regset *regset, 731 unsigned int pos, unsigned int count, 732 const void *kbuf, const void __user *ubuf) 733 { 734 int rc = 0; 735 736 if (target == current) 737 save_access_regs(target->thread.acrs); 738 739 if (kbuf) { 740 const unsigned long *k = kbuf; 741 while (count > 0 && !rc) { 742 rc = __poke_user(target, pos, *k++); 743 count -= sizeof(*k); 744 pos += sizeof(*k); 745 } 746 } else { 747 const unsigned long __user *u = ubuf; 748 while (count > 0 && !rc) { 749 unsigned long word; 750 rc = __get_user(word, u++); 751 if (rc) 752 break; 753 rc = __poke_user(target, pos, word); 754 count -= sizeof(*u); 755 pos += sizeof(*u); 756 } 757 } 758 759 if (rc == 0 && target == current) 760 restore_access_regs(target->thread.acrs); 761 762 return rc; 763 } 764 765 static int s390_fpregs_get(struct task_struct *target, 766 const struct user_regset *regset, unsigned int pos, 767 unsigned int count, void *kbuf, void __user *ubuf) 768 { 769 if (target == current) 770 save_fp_regs(&target->thread.fp_regs); 771 772 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, 773 &target->thread.fp_regs, 0, -1); 774 } 775 776 static int s390_fpregs_set(struct task_struct *target, 777 const struct user_regset *regset, unsigned int pos, 778 unsigned int count, const void *kbuf, 779 const void __user *ubuf) 780 { 781 int rc = 0; 782 783 if (target == current) 784 save_fp_regs(&target->thread.fp_regs); 785 786 /* If setting FPC, must validate it first. */ 787 if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) { 788 u32 fpc[2] = { target->thread.fp_regs.fpc, 0 }; 789 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc, 790 0, offsetof(s390_fp_regs, fprs)); 791 if (rc) 792 return rc; 793 if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0) 794 return -EINVAL; 795 target->thread.fp_regs.fpc = fpc[0]; 796 } 797 798 if (rc == 0 && count > 0) 799 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, 800 target->thread.fp_regs.fprs, 801 offsetof(s390_fp_regs, fprs), -1); 802 803 if (rc == 0 && target == current) 804 restore_fp_regs(&target->thread.fp_regs); 805 806 return rc; 807 } 808 809 #ifdef CONFIG_64BIT 810 811 static int s390_last_break_get(struct task_struct *target, 812 const struct user_regset *regset, 813 unsigned int pos, unsigned int count, 814 void *kbuf, void __user *ubuf) 815 { 816 if (count > 0) { 817 if (kbuf) { 818 unsigned long *k = kbuf; 819 *k = task_thread_info(target)->last_break; 820 } else { 821 unsigned long __user *u = ubuf; 822 if (__put_user(task_thread_info(target)->last_break, u)) 823 return -EFAULT; 824 } 825 } 826 return 0; 827 } 828 829 #endif 830 831 static const struct user_regset s390_regsets[] = { 832 [REGSET_GENERAL] = { 833 .core_note_type = NT_PRSTATUS, 834 .n = sizeof(s390_regs) / sizeof(long), 835 .size = sizeof(long), 836 .align = sizeof(long), 837 .get = s390_regs_get, 838 .set = s390_regs_set, 839 }, 840 [REGSET_FP] = { 841 .core_note_type = NT_PRFPREG, 842 .n = sizeof(s390_fp_regs) / sizeof(long), 843 .size = sizeof(long), 844 .align = sizeof(long), 845 .get = s390_fpregs_get, 846 .set = s390_fpregs_set, 847 }, 848 #ifdef CONFIG_64BIT 849 [REGSET_LAST_BREAK] = { 850 .core_note_type = NT_S390_LAST_BREAK, 851 .n = 1, 852 .size = sizeof(long), 853 .align = sizeof(long), 854 .get = s390_last_break_get, 855 }, 856 #endif 857 }; 858 859 static const struct user_regset_view user_s390_view = { 860 .name = UTS_MACHINE, 861 .e_machine = EM_S390, 862 .regsets = s390_regsets, 863 .n = ARRAY_SIZE(s390_regsets) 864 }; 865 866 #ifdef CONFIG_COMPAT 867 static int s390_compat_regs_get(struct task_struct *target, 868 const struct user_regset *regset, 869 unsigned int pos, unsigned int count, 870 void *kbuf, void __user *ubuf) 871 { 872 if (target == current) 873 save_access_regs(target->thread.acrs); 874 875 if (kbuf) { 876 compat_ulong_t *k = kbuf; 877 while (count > 0) { 878 *k++ = __peek_user_compat(target, pos); 879 count -= sizeof(*k); 880 pos += sizeof(*k); 881 } 882 } else { 883 compat_ulong_t __user *u = ubuf; 884 while (count > 0) { 885 if (__put_user(__peek_user_compat(target, pos), u++)) 886 return -EFAULT; 887 count -= sizeof(*u); 888 pos += sizeof(*u); 889 } 890 } 891 return 0; 892 } 893 894 static int s390_compat_regs_set(struct task_struct *target, 895 const struct user_regset *regset, 896 unsigned int pos, unsigned int count, 897 const void *kbuf, const void __user *ubuf) 898 { 899 int rc = 0; 900 901 if (target == current) 902 save_access_regs(target->thread.acrs); 903 904 if (kbuf) { 905 const compat_ulong_t *k = kbuf; 906 while (count > 0 && !rc) { 907 rc = __poke_user_compat(target, pos, *k++); 908 count -= sizeof(*k); 909 pos += sizeof(*k); 910 } 911 } else { 912 const compat_ulong_t __user *u = ubuf; 913 while (count > 0 && !rc) { 914 compat_ulong_t word; 915 rc = __get_user(word, u++); 916 if (rc) 917 break; 918 rc = __poke_user_compat(target, pos, word); 919 count -= sizeof(*u); 920 pos += sizeof(*u); 921 } 922 } 923 924 if (rc == 0 && target == current) 925 restore_access_regs(target->thread.acrs); 926 927 return rc; 928 } 929 930 static int s390_compat_regs_high_get(struct task_struct *target, 931 const struct user_regset *regset, 932 unsigned int pos, unsigned int count, 933 void *kbuf, void __user *ubuf) 934 { 935 compat_ulong_t *gprs_high; 936 937 gprs_high = (compat_ulong_t *) 938 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)]; 939 if (kbuf) { 940 compat_ulong_t *k = kbuf; 941 while (count > 0) { 942 *k++ = *gprs_high; 943 gprs_high += 2; 944 count -= sizeof(*k); 945 } 946 } else { 947 compat_ulong_t __user *u = ubuf; 948 while (count > 0) { 949 if (__put_user(*gprs_high, u++)) 950 return -EFAULT; 951 gprs_high += 2; 952 count -= sizeof(*u); 953 } 954 } 955 return 0; 956 } 957 958 static int s390_compat_regs_high_set(struct task_struct *target, 959 const struct user_regset *regset, 960 unsigned int pos, unsigned int count, 961 const void *kbuf, const void __user *ubuf) 962 { 963 compat_ulong_t *gprs_high; 964 int rc = 0; 965 966 gprs_high = (compat_ulong_t *) 967 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)]; 968 if (kbuf) { 969 const compat_ulong_t *k = kbuf; 970 while (count > 0) { 971 *gprs_high = *k++; 972 *gprs_high += 2; 973 count -= sizeof(*k); 974 } 975 } else { 976 const compat_ulong_t __user *u = ubuf; 977 while (count > 0 && !rc) { 978 unsigned long word; 979 rc = __get_user(word, u++); 980 if (rc) 981 break; 982 *gprs_high = word; 983 *gprs_high += 2; 984 count -= sizeof(*u); 985 } 986 } 987 988 return rc; 989 } 990 991 static int s390_compat_last_break_get(struct task_struct *target, 992 const struct user_regset *regset, 993 unsigned int pos, unsigned int count, 994 void *kbuf, void __user *ubuf) 995 { 996 compat_ulong_t last_break; 997 998 if (count > 0) { 999 last_break = task_thread_info(target)->last_break; 1000 if (kbuf) { 1001 unsigned long *k = kbuf; 1002 *k = last_break; 1003 } else { 1004 unsigned long __user *u = ubuf; 1005 if (__put_user(last_break, u)) 1006 return -EFAULT; 1007 } 1008 } 1009 return 0; 1010 } 1011 1012 static const struct user_regset s390_compat_regsets[] = { 1013 [REGSET_GENERAL] = { 1014 .core_note_type = NT_PRSTATUS, 1015 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t), 1016 .size = sizeof(compat_long_t), 1017 .align = sizeof(compat_long_t), 1018 .get = s390_compat_regs_get, 1019 .set = s390_compat_regs_set, 1020 }, 1021 [REGSET_FP] = { 1022 .core_note_type = NT_PRFPREG, 1023 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t), 1024 .size = sizeof(compat_long_t), 1025 .align = sizeof(compat_long_t), 1026 .get = s390_fpregs_get, 1027 .set = s390_fpregs_set, 1028 }, 1029 [REGSET_LAST_BREAK] = { 1030 .core_note_type = NT_S390_LAST_BREAK, 1031 .n = 1, 1032 .size = sizeof(long), 1033 .align = sizeof(long), 1034 .get = s390_compat_last_break_get, 1035 }, 1036 [REGSET_GENERAL_EXTENDED] = { 1037 .core_note_type = NT_S390_HIGH_GPRS, 1038 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t), 1039 .size = sizeof(compat_long_t), 1040 .align = sizeof(compat_long_t), 1041 .get = s390_compat_regs_high_get, 1042 .set = s390_compat_regs_high_set, 1043 }, 1044 }; 1045 1046 static const struct user_regset_view user_s390_compat_view = { 1047 .name = "s390", 1048 .e_machine = EM_S390, 1049 .regsets = s390_compat_regsets, 1050 .n = ARRAY_SIZE(s390_compat_regsets) 1051 }; 1052 #endif 1053 1054 const struct user_regset_view *task_user_regset_view(struct task_struct *task) 1055 { 1056 #ifdef CONFIG_COMPAT 1057 if (test_tsk_thread_flag(task, TIF_31BIT)) 1058 return &user_s390_compat_view; 1059 #endif 1060 return &user_s390_view; 1061 } 1062 1063 static const char *gpr_names[NUM_GPRS] = { 1064 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", 1065 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15", 1066 }; 1067 1068 unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset) 1069 { 1070 if (offset >= NUM_GPRS) 1071 return 0; 1072 return regs->gprs[offset]; 1073 } 1074 1075 int regs_query_register_offset(const char *name) 1076 { 1077 unsigned long offset; 1078 1079 if (!name || *name != 'r') 1080 return -EINVAL; 1081 if (strict_strtoul(name + 1, 10, &offset)) 1082 return -EINVAL; 1083 if (offset >= NUM_GPRS) 1084 return -EINVAL; 1085 return offset; 1086 } 1087 1088 const char *regs_query_register_name(unsigned int offset) 1089 { 1090 if (offset >= NUM_GPRS) 1091 return NULL; 1092 return gpr_names[offset]; 1093 } 1094 1095 static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) 1096 { 1097 unsigned long ksp = kernel_stack_pointer(regs); 1098 1099 return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1)); 1100 } 1101 1102 /** 1103 * regs_get_kernel_stack_nth() - get Nth entry of the stack 1104 * @regs:pt_regs which contains kernel stack pointer. 1105 * @n:stack entry number. 1106 * 1107 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which 1108 * is specifined by @regs. If the @n th entry is NOT in the kernel stack, 1109 * this returns 0. 1110 */ 1111 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) 1112 { 1113 unsigned long addr; 1114 1115 addr = kernel_stack_pointer(regs) + n * sizeof(long); 1116 if (!regs_within_kernel_stack(regs, addr)) 1117 return 0; 1118 return *(unsigned long *)addr; 1119 } 1120