granicus.if.org Git - strace/blob - syscall.c

   1 /*
   2  * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
   3  * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
   4  * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
   5  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
   6  * Copyright (c) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
   7  *                     Linux for s390 port by D.J. Barrow
   8  *                    <barrow_dj@mail.yahoo.com,djbarrow@de.ibm.com>
   9  * Copyright (c) 1999-2018 The strace developers.
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. The name of the author may not be used to endorse or promote products
  21  *    derived from this software without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #include "defs.h"
  36 #include "mmap_cache.h"
  37 #include "native_defs.h"
  38 #include "ptrace.h"
  39 #include "nsig.h"
  40 #include "number_set.h"
  41 #include "delay.h"
  42 #include "retval.h"
  43 #include <limits.h>
  44
  45 /* for struct iovec */
  46 #include <sys/uio.h>
  47
  48 /* for __X32_SYSCALL_BIT */
  49 #include <asm/unistd.h>
  50
  51 #include "regs.h"
  52
  53 #if defined(SPARC64)
  54 # undef PTRACE_GETREGS
  55 # define PTRACE_GETREGS PTRACE_GETREGS64
  56 # undef PTRACE_SETREGS
  57 # define PTRACE_SETREGS PTRACE_SETREGS64
  58 #endif
  59
  60 #ifndef NT_PRSTATUS
  61 # define NT_PRSTATUS 1
  62 #endif
  63
  64 #include "syscall.h"
  65 #include "xstring.h"
  66
  67 /* Define these shorthand notations to simplify the syscallent files. */
  68 #include "sysent_shorthand_defs.h"
  69
  70 #define SEN(syscall_name) SEN_ ## syscall_name, SYS_FUNC_NAME(sys_ ## syscall_name)
  71
  72 const struct_sysent sysent0[] = {
  73 #include "syscallent.h"
  74 };
  75
  76 #if SUPPORTED_PERSONALITIES > 1
  77 # include PERSONALITY1_INCLUDE_FUNCS
  78 static const struct_sysent sysent1[] = {
  79 # include "syscallent1.h"
  80 };
  81 #endif
  82
  83 #if SUPPORTED_PERSONALITIES > 2
  84 # include PERSONALITY2_INCLUDE_FUNCS
  85 static const struct_sysent sysent2[] = {
  86 # include "syscallent2.h"
  87 };
  88 #endif
  89
  90 /* Now undef them since short defines cause wicked namespace pollution. */
  91 #include "sysent_shorthand_undefs.h"
  92
  93 /*
  94  * `ioctlent[012].h' files are automatically generated by the auxiliary
  95  * program `ioctlsort', such that the list is sorted by the `code' field.
  96  * This has the side-effect of resolving the _IO.. macros into
  97  * plain integers, eliminating the need to include here everything
  98  * in "/usr/include".
  99  */
 100
 101 const char *const errnoent0[] = {
 102 #include "errnoent.h"
 103 };
 104 const char *const signalent0[] = {
 105 #include "signalent.h"
 106 };
 107 const struct_ioctlent ioctlent0[] = {
 108 #include "ioctlent0.h"
 109 };
 110
 111 #if SUPPORTED_PERSONALITIES > 1
 112 static const char *const errnoent1[] = {
 113 # include "errnoent1.h"
 114 };
 115 static const char *const signalent1[] = {
 116 # include "signalent1.h"
 117 };
 118 static const struct_ioctlent ioctlent1[] = {
 119 # include "ioctlent1.h"
 120 };
 121 # include PERSONALITY0_INCLUDE_PRINTERS_DECLS
 122 static const struct_printers printers0 = {
 123 # include PERSONALITY0_INCLUDE_PRINTERS_DEFS
 124 };
 125 # include PERSONALITY1_INCLUDE_PRINTERS_DECLS
 126 static const struct_printers printers1 = {
 127 # include PERSONALITY1_INCLUDE_PRINTERS_DEFS
 128 };
 129 #endif
 130
 131 #if SUPPORTED_PERSONALITIES > 2
 132 static const char *const errnoent2[] = {
 133 # include "errnoent2.h"
 134 };
 135 static const char *const signalent2[] = {
 136 # include "signalent2.h"
 137 };
 138 static const struct_ioctlent ioctlent2[] = {
 139 # include "ioctlent2.h"
 140 };
 141 # include PERSONALITY2_INCLUDE_PRINTERS_DECLS
 142 static const struct_printers printers2 = {
 143 # include PERSONALITY2_INCLUDE_PRINTERS_DEFS
 144 };
 145 #endif
 146
 147 enum {
 148         nsyscalls0 = ARRAY_SIZE(sysent0)
 149 #if SUPPORTED_PERSONALITIES > 1
 150         , nsyscalls1 = ARRAY_SIZE(sysent1)
 151 # if SUPPORTED_PERSONALITIES > 2
 152         , nsyscalls2 = ARRAY_SIZE(sysent2)
 153 # endif
 154 #endif
 155 };
 156
 157 enum {
 158         nerrnos0 = ARRAY_SIZE(errnoent0)
 159 #if SUPPORTED_PERSONALITIES > 1
 160         , nerrnos1 = ARRAY_SIZE(errnoent1)
 161 # if SUPPORTED_PERSONALITIES > 2
 162         , nerrnos2 = ARRAY_SIZE(errnoent2)
 163 # endif
 164 #endif
 165 };
 166
 167 enum {
 168         nsignals0 = ARRAY_SIZE(signalent0)
 169 #if SUPPORTED_PERSONALITIES > 1
 170         , nsignals1 = ARRAY_SIZE(signalent1)
 171 # if SUPPORTED_PERSONALITIES > 2
 172         , nsignals2 = ARRAY_SIZE(signalent2)
 173 # endif
 174 #endif
 175 };
 176
 177 enum {
 178         nioctlents0 = ARRAY_SIZE(ioctlent0)
 179 #if SUPPORTED_PERSONALITIES > 1
 180         , nioctlents1 = ARRAY_SIZE(ioctlent1)
 181 # if SUPPORTED_PERSONALITIES > 2
 182         , nioctlents2 = ARRAY_SIZE(ioctlent2)
 183 # endif
 184 #endif
 185 };
 186
 187 #if SUPPORTED_PERSONALITIES > 1
 188 const struct_sysent *sysent = sysent0;
 189 const char *const *errnoent = errnoent0;
 190 const char *const *signalent = signalent0;
 191 const struct_ioctlent *ioctlent = ioctlent0;
 192 const struct_printers *printers = &printers0;
 193 #endif
 194
 195 unsigned nsyscalls = nsyscalls0;
 196 unsigned nerrnos = nerrnos0;
 197 unsigned nsignals = nsignals0;
 198 unsigned nioctlents = nioctlents0;
 199
 200 const unsigned int nsyscall_vec[SUPPORTED_PERSONALITIES] = {
 201         nsyscalls0,
 202 #if SUPPORTED_PERSONALITIES > 1
 203         nsyscalls1,
 204 #endif
 205 #if SUPPORTED_PERSONALITIES > 2
 206         nsyscalls2,
 207 #endif
 208 };
 209 const struct_sysent *const sysent_vec[SUPPORTED_PERSONALITIES] = {
 210         sysent0,
 211 #if SUPPORTED_PERSONALITIES > 1
 212         sysent1,
 213 #endif
 214 #if SUPPORTED_PERSONALITIES > 2
 215         sysent2,
 216 #endif
 217 };
 218
 219 const char *const personality_names[] =
 220 # if defined X86_64
 221         {"64 bit", "32 bit", "x32"}
 222 # elif defined X32
 223         {"x32", "32 bit"}
 224 # elif SUPPORTED_PERSONALITIES == 2
 225         {"64 bit", "32 bit"}
 226 # else
 227         {STRINGIFY_VAL(__WORDSIZE) " bit"}
 228 # endif
 229         ;
 230
 231 #if SUPPORTED_PERSONALITIES > 1
 232
 233 unsigned current_personality;
 234
 235 # ifndef current_wordsize
 236 unsigned current_wordsize = PERSONALITY0_WORDSIZE;
 237 static const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
 238         PERSONALITY0_WORDSIZE,
 239         PERSONALITY1_WORDSIZE,
 240 # if SUPPORTED_PERSONALITIES > 2
 241         PERSONALITY2_WORDSIZE,
 242 # endif
 243 };
 244 # endif
 245
 246 # ifndef current_klongsize
 247 unsigned current_klongsize = PERSONALITY0_KLONGSIZE;
 248 static const int personality_klongsize[SUPPORTED_PERSONALITIES] = {
 249         PERSONALITY0_KLONGSIZE,
 250         PERSONALITY1_KLONGSIZE,
 251 #  if SUPPORTED_PERSONALITIES > 2
 252         PERSONALITY2_KLONGSIZE,
 253 #  endif
 254 };
 255 # endif
 256
 257 void
 258 set_personality(unsigned int personality)
 259 {
 260         if (personality == current_personality)
 261                 return;
 262
 263         if (personality >= SUPPORTED_PERSONALITIES)
 264                 error_msg_and_die("Requested switch to unsupported personality "
 265                                   "%u", personality);
 266
 267         nsyscalls = nsyscall_vec[personality];
 268         sysent = sysent_vec[personality];
 269
 270         switch (personality) {
 271         case 0:
 272                 errnoent = errnoent0;
 273                 nerrnos = nerrnos0;
 274                 ioctlent = ioctlent0;
 275                 nioctlents = nioctlents0;
 276                 signalent = signalent0;
 277                 nsignals = nsignals0;
 278                 printers = &printers0;
 279                 break;
 280
 281         case 1:
 282                 errnoent = errnoent1;
 283                 nerrnos = nerrnos1;
 284                 ioctlent = ioctlent1;
 285                 nioctlents = nioctlents1;
 286                 signalent = signalent1;
 287                 nsignals = nsignals1;
 288                 printers = &printers1;
 289                 break;
 290
 291 # if SUPPORTED_PERSONALITIES > 2
 292         case 2:
 293                 errnoent = errnoent2;
 294                 nerrnos = nerrnos2;
 295                 ioctlent = ioctlent2;
 296                 nioctlents = nioctlents2;
 297                 signalent = signalent2;
 298                 nsignals = nsignals2;
 299                 printers = &printers2;
 300                 break;
 301 # endif
 302         }
 303
 304         current_personality = personality;
 305 # ifndef current_wordsize
 306         current_wordsize = personality_wordsize[personality];
 307 # endif
 308 # ifndef current_klongsize
 309         current_klongsize = personality_klongsize[personality];
 310 # endif
 311 }
 312
 313 static void
 314 update_personality(struct tcb *tcp, unsigned int personality)
 315 {
 316         static bool need_mpers_warning[] =
 317                 { false, !HAVE_PERSONALITY_1_MPERS, !HAVE_PERSONALITY_2_MPERS };
 318
 319         set_personality(personality);
 320
 321         if (personality == tcp->currpers)
 322                 return;
 323         tcp->currpers = personality;
 324
 325         if (!qflag) {
 326                 error_msg("[ Process PID=%d runs in %s mode. ]",
 327                           tcp->pid, personality_names[personality]);
 328         }
 329
 330         if (need_mpers_warning[personality]) {
 331                 error_msg("WARNING: Proper structure decoding for this "
 332                           "personality is not supported, please consider "
 333                           "building strace with mpers support enabled.");
 334                 need_mpers_warning[personality] = false;
 335         }
 336 }
 337 #endif
 338
 339 #ifdef SYS_socket_subcall
 340 static void
 341 decode_socket_subcall(struct tcb *tcp)
 342 {
 343         const int call = tcp->u_arg[0];
 344
 345         if (call < 1 || call >= SYS_socket_nsubcalls)
 346                 return;
 347
 348         const kernel_ulong_t scno = SYS_socket_subcall + call;
 349         const unsigned int nargs = sysent[scno].nargs;
 350         uint64_t buf[nargs];
 351
 352         if (umoven(tcp, tcp->u_arg[1], nargs * current_wordsize, buf) < 0)
 353                 return;
 354
 355         tcp->scno = scno;
 356         tcp->qual_flg = qual_flags(scno);
 357         tcp->s_ent = &sysent[scno];
 358
 359         unsigned int i;
 360         for (i = 0; i < nargs; ++i)
 361                 tcp->u_arg[i] = (sizeof(uint32_t) == current_wordsize)
 362                                 ? ((uint32_t *) (void *) buf)[i] : buf[i];
 363 }
 364 #endif /* SYS_socket_subcall */
 365
 366 #ifdef SYS_ipc_subcall
 367 static void
 368 decode_ipc_subcall(struct tcb *tcp)
 369 {
 370         unsigned int call = tcp->u_arg[0];
 371         const unsigned int version = call >> 16;
 372
 373         if (version) {
 374 # if defined S390 || defined S390X
 375                 return;
 376 # else
 377 #  ifdef SPARC64
 378                 if (current_wordsize == 8)
 379                         return;
 380 #  endif
 381                 set_tcb_priv_ulong(tcp, version);
 382                 call &= 0xffff;
 383 # endif
 384         }
 385
 386         switch (call) {
 387                 case  1: case  2: case  3: case  4:
 388                 case 11: case 12: case 13: case 14:
 389                 case 21: case 22: case 23: case 24:
 390                         break;
 391                 default:
 392                         return;
 393         }
 394
 395         tcp->scno = SYS_ipc_subcall + call;
 396         tcp->qual_flg = qual_flags(tcp->scno);
 397         tcp->s_ent = &sysent[tcp->scno];
 398
 399         const unsigned int n = tcp->s_ent->nargs;
 400         unsigned int i;
 401         for (i = 0; i < n; i++)
 402                 tcp->u_arg[i] = tcp->u_arg[i + 1];
 403 }
 404 #endif /* SYS_ipc_subcall */
 405
 406 #ifdef SYS_syscall_subcall
 407 static void
 408 decode_syscall_subcall(struct tcb *tcp)
 409 {
 410         if (!scno_is_valid(tcp->u_arg[0]))
 411                 return;
 412         tcp->scno = tcp->u_arg[0];
 413         tcp->qual_flg = qual_flags(tcp->scno);
 414         tcp->s_ent = &sysent[tcp->scno];
 415         memmove(&tcp->u_arg[0], &tcp->u_arg[1],
 416                 sizeof(tcp->u_arg) - sizeof(tcp->u_arg[0]));
 417 # ifdef LINUX_MIPSO32
 418         /*
 419          * Fetching the last arg of 7-arg syscalls (fadvise64_64
 420          * and sync_file_range) requires additional code,
 421          * see linux/mips/get_syscall_args.c
 422          */
 423         if (tcp->s_ent->nargs == MAX_ARGS) {
 424                 if (umoven(tcp,
 425                            mips_REG_SP + MAX_ARGS * sizeof(tcp->u_arg[0]),
 426                            sizeof(tcp->u_arg[0]),
 427                            &tcp->u_arg[MAX_ARGS - 1]) < 0)
 428                 tcp->u_arg[MAX_ARGS - 1] = 0;
 429         }
 430 # endif /* LINUX_MIPSO32 */
 431 }
 432 #endif /* SYS_syscall_subcall */
 433
 434 static void
 435 dumpio(struct tcb *tcp)
 436 {
 437         if (syserror(tcp))
 438                 return;
 439
 440         int fd = tcp->u_arg[0];
 441         if (fd < 0)
 442                 return;
 443
 444         if (is_number_in_set(fd, read_set)) {
 445                 switch (tcp->s_ent->sen) {
 446                 case SEN_read:
 447                 case SEN_pread:
 448                 case SEN_recv:
 449                 case SEN_recvfrom:
 450                 case SEN_mq_timedreceive:
 451                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
 452                         return;
 453                 case SEN_readv:
 454                 case SEN_preadv:
 455                 case SEN_preadv2:
 456                         dumpiov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1],
 457                                      tcp->u_rval);
 458                         return;
 459                 case SEN_recvmsg:
 460                         dumpiov_in_msghdr(tcp, tcp->u_arg[1], tcp->u_rval);
 461                         return;
 462                 case SEN_recvmmsg:
 463                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 464                         return;
 465                 }
 466         }
 467         if (is_number_in_set(fd, write_set)) {
 468                 switch (tcp->s_ent->sen) {
 469                 case SEN_write:
 470                 case SEN_pwrite:
 471                 case SEN_send:
 472                 case SEN_sendto:
 473                 case SEN_mq_timedsend:
 474                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
 475                         break;
 476                 case SEN_writev:
 477                 case SEN_pwritev:
 478                 case SEN_pwritev2:
 479                 case SEN_vmsplice:
 480                         dumpiov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1], -1);
 481                         break;
 482                 case SEN_sendmsg:
 483                         dumpiov_in_msghdr(tcp, tcp->u_arg[1], -1);
 484                         break;
 485                 case SEN_sendmmsg:
 486                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 487                         break;
 488                 }
 489         }
 490 }
 491
 492 const char *
 493 err_name(unsigned long err)
 494 {
 495         if ((err < nerrnos) && errnoent[err])
 496                 return errnoent[err];
 497
 498         return NULL;
 499 }
 500
 501 static long get_regs(struct tcb *);
 502 static int get_syscall_args(struct tcb *);
 503 static int get_syscall_result(struct tcb *);
 504 static int arch_get_scno(struct tcb *tcp);
 505 static int arch_set_scno(struct tcb *, kernel_ulong_t);
 506 static void get_error(struct tcb *, const bool);
 507 static int arch_set_error(struct tcb *);
 508 static int arch_set_success(struct tcb *);
 509
 510 struct inject_opts *inject_vec[SUPPORTED_PERSONALITIES];
 511
 512 static struct inject_opts *
 513 tcb_inject_opts(struct tcb *tcp)
 514 {
 515         return (scno_in_range(tcp->scno) && tcp->inject_vec[current_personality])
 516                ? &tcp->inject_vec[current_personality][tcp->scno] : NULL;
 517 }
 518
 519
 520 static long
 521 tamper_with_syscall_entering(struct tcb *tcp, unsigned int *signo)
 522 {
 523         if (!tcp->inject_vec[current_personality]) {
 524                 tcp->inject_vec[current_personality] =
 525                         xcalloc(nsyscalls, sizeof(**inject_vec));
 526                 memcpy(tcp->inject_vec[current_personality],
 527                        inject_vec[current_personality],
 528                        nsyscalls * sizeof(**inject_vec));
 529         }
 530
 531         struct inject_opts *opts = tcb_inject_opts(tcp);
 532
 533         if (!opts || opts->first == 0)
 534                 return 0;
 535
 536         --opts->first;
 537
 538         if (opts->first != 0)
 539                 return 0;
 540
 541         opts->first = opts->step;
 542
 543         if (!recovering(tcp)) {
 544                 if (opts->data.flags & INJECT_F_SIGNAL)
 545                         *signo = opts->data.signo;
 546                 if (opts->data.flags & (INJECT_F_ERROR | INJECT_F_RETVAL) &&
 547                     !arch_set_scno(tcp, -1))
 548                         tcp->flags |= TCB_TAMPERED;
 549                 if (opts->data.flags & INJECT_F_DELAY_ENTER)
 550                         delay_tcb(tcp, opts->data.delay_idx, true);
 551                 if (opts->data.flags & INJECT_F_DELAY_EXIT)
 552                         tcp->flags |= TCB_INJECT_DELAY_EXIT;
 553         }
 554
 555         return 0;
 556 }
 557
 558 static long
 559 tamper_with_syscall_exiting(struct tcb *tcp)
 560 {
 561         struct inject_opts *opts = tcb_inject_opts(tcp);
 562         if (!opts)
 563                 return 0;
 564
 565         if (inject_delay_exit(tcp))
 566                 delay_tcb(tcp, opts->data.delay_idx, false);
 567
 568         if (!syscall_tampered(tcp))
 569                 return 0;
 570
 571         if (!syserror(tcp)) {
 572                 error_msg("Failed to tamper with process %d: got no error "
 573                           "(return value %#" PRI_klx ")",
 574                           tcp->pid, tcp->u_rval);
 575
 576                 return 1;
 577         }
 578
 579         bool update_tcb = false;
 580
 581         if (opts->data.flags & INJECT_F_RETVAL) {
 582                 kernel_long_t inject_rval =
 583                         retval_get(opts->data.rval_idx);
 584                 kernel_long_t u_rval = tcp->u_rval;
 585
 586                 tcp->u_rval = inject_rval;
 587                 if (arch_set_success(tcp)) {
 588                         tcp->u_rval = u_rval;
 589                 } else {
 590                         update_tcb = true;
 591                         tcp->u_error = 0;
 592                 }
 593         } else {
 594                 unsigned long new_error = retval_get(opts->data.rval_idx);
 595
 596                 if (new_error != tcp->u_error && new_error <= MAX_ERRNO_VALUE) {
 597                         unsigned long u_error = tcp->u_error;
 598
 599                         tcp->u_error = new_error;
 600                         if (arch_set_error(tcp)) {
 601                                 tcp->u_error = u_error;
 602                         } else {
 603                                 update_tcb = true;
 604                         }
 605                 }
 606         }
 607
 608         if (update_tcb) {
 609                 tcp->u_error = 0;
 610                 get_error(tcp, !(tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS));
 611         }
 612
 613         return 0;
 614 }
 615
 616 /*
 617  * Returns:
 618  * 0: "ignore this ptrace stop", bail out silently.
 619  * 1: ok, decoded; call
 620  *    syscall_entering_finish(tcp, syscall_entering_trace(tcp, ...)).
 621  * other: error; call syscall_entering_finish(tcp, res), where res is the value
 622  *    returned.
 623  */
 624 int
 625 syscall_entering_decode(struct tcb *tcp)
 626 {
 627         int res = get_scno(tcp);
 628         if (res == 0)
 629                 return res;
 630         int scno_good = res;
 631         if (res != 1 || (res = get_syscall_args(tcp)) != 1) {
 632                 printleader(tcp);
 633                 tprintf("%s(", scno_good == 1 ? tcp->s_ent->sys_name : "????");
 634                 /*
 635                  * " <unavailable>" will be added later by the code which
 636                  * detects ptrace errors.
 637                  */
 638                 return res;
 639         }
 640
 641 #if defined SYS_ipc_subcall     \
 642  || defined SYS_socket_subcall  \
 643  || defined SYS_syscall_subcall
 644         for (;;) {
 645                 switch (tcp->s_ent->sen) {
 646 # ifdef SYS_ipc_subcall
 647                 case SEN_ipc:
 648                         decode_ipc_subcall(tcp);
 649                         break;
 650 # endif
 651 # ifdef SYS_socket_subcall
 652                 case SEN_socketcall:
 653                         decode_socket_subcall(tcp);
 654                         break;
 655 # endif
 656 # ifdef SYS_syscall_subcall
 657                 case SEN_syscall:
 658                         decode_syscall_subcall(tcp);
 659                         if (tcp->s_ent->sen != SEN_syscall)
 660                                 continue;
 661                         break;
 662 # endif
 663                 }
 664                 break;
 665         }
 666 #endif
 667
 668         return 1;
 669 }
 670
 671 int
 672 syscall_entering_trace(struct tcb *tcp, unsigned int *sig)
 673 {
 674         /* Restrain from fault injection while the trace executes strace code. */
 675         if (hide_log(tcp)) {
 676                 tcp->qual_flg &= ~QUAL_INJECT;
 677         }
 678
 679         switch (tcp->s_ent->sen) {
 680                 case SEN_execve:
 681                 case SEN_execveat:
 682 #if defined SPARC || defined SPARC64
 683                 case SEN_execv:
 684 #endif
 685                         tcp->flags &= ~TCB_HIDE_LOG;
 686                         break;
 687         }
 688
 689         if (!traced(tcp) || (tracing_paths && !pathtrace_match(tcp))) {
 690                 tcp->flags |= TCB_FILTERED;
 691                 return 0;
 692         }
 693
 694         tcp->flags &= ~TCB_FILTERED;
 695
 696         if (hide_log(tcp)) {
 697                 return 0;
 698         }
 699
 700         if (inject(tcp))
 701                 tamper_with_syscall_entering(tcp, sig);
 702
 703         if (cflag == CFLAG_ONLY_STATS) {
 704                 return 0;
 705         }
 706
 707 #ifdef USE_LIBUNWIND
 708         if (stack_trace_enabled) {
 709                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
 710                         unwind_capture_stacktrace(tcp);
 711         }
 712 #endif
 713
 714         printleader(tcp);
 715         tprintf("%s(", tcp->s_ent->sys_name);
 716         int res = raw(tcp) ? printargs(tcp) : tcp->s_ent->sys_func(tcp);
 717         fflush(tcp->outf);
 718         return res;
 719 }
 720
 721 void
 722 syscall_entering_finish(struct tcb *tcp, int res)
 723 {
 724         tcp->flags |= TCB_INSYSCALL;
 725         tcp->sys_func_rval = res;
 726         /* Measure the entrance time as late as possible to avoid errors. */
 727         if ((Tflag || cflag) && !filtered(tcp))
 728                 clock_gettime(CLOCK_MONOTONIC, &tcp->etime);
 729 }
 730
 731 /* Returns:
 732  * 0: "bail out".
 733  * 1: ok.
 734  * -1: error in one of ptrace ops.
 735  *
 736  * If not 0, call syscall_exiting_trace(tcp, res), where res is the return
 737  *    value. Anyway, call syscall_exiting_finish(tcp) then.
 738  */
 739 int
 740 syscall_exiting_decode(struct tcb *tcp, struct timespec *pts)
 741 {
 742         /* Measure the exit time as early as possible to avoid errors. */
 743         if ((Tflag || cflag) && !(filtered(tcp) || hide_log(tcp)))
 744                 clock_gettime(CLOCK_MONOTONIC, pts);
 745
 746         if (mmap_cache_is_enabled()) {
 747                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
 748                         mmap_cache_invalidate(tcp);
 749         }
 750
 751         if (filtered(tcp) || hide_log(tcp))
 752                 return 0;
 753
 754 #if SUPPORTED_PERSONALITIES > 1
 755         update_personality(tcp, tcp->currpers);
 756 #endif
 757
 758         return get_syscall_result(tcp);
 759 }
 760
 761 int
 762 syscall_exiting_trace(struct tcb *tcp, struct timespec *ts, int res)
 763 {
 764         if (syscall_tampered(tcp) || inject_delay_exit(tcp))
 765                 tamper_with_syscall_exiting(tcp);
 766
 767         if (cflag) {
 768                 count_syscall(tcp, ts);
 769                 if (cflag == CFLAG_ONLY_STATS) {
 770                         return 0;
 771                 }
 772         }
 773
 774         /* If not in -ff mode, and printing_tcp != tcp,
 775          * then the log currently does not end with output
 776          * of _our syscall entry_, but with something else.
 777          * We need to say which syscall's return is this.
 778          *
 779          * Forced reprinting via TCB_REPRINT is used only by
 780          * "strace -ff -oLOG test/threaded_execve" corner case.
 781          * It's the only case when -ff mode needs reprinting.
 782          */
 783         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
 784                 tcp->flags &= ~TCB_REPRINT;
 785                 printleader(tcp);
 786                 tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
 787         }
 788         printing_tcp = tcp;
 789
 790         tcp->s_prev_ent = NULL;
 791         if (res != 1) {
 792                 /* There was error in one of prior ptrace ops */
 793                 tprints(") ");
 794                 tabto();
 795                 tprints("= ? <unavailable>\n");
 796                 line_ended();
 797                 return res;
 798         }
 799         tcp->s_prev_ent = tcp->s_ent;
 800
 801         int sys_res = 0;
 802         if (raw(tcp)) {
 803                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
 804         } else {
 805         /* FIXME: not_failing_only (IOW, option -z) is broken:
 806          * failure of syscall is known only after syscall return.
 807          * Thus we end up with something like this on, say, ENOENT:
 808          *     open("does_not_exist", O_RDONLY <unfinished ...>
 809          *     {next syscall decode}
 810          * whereas the intended result is that open(...) line
 811          * is not shown at all.
 812          */
 813                 if (not_failing_only && tcp->u_error)
 814                         return 0;       /* ignore failed syscalls */
 815                 if (tcp->sys_func_rval & RVAL_DECODED)
 816                         sys_res = tcp->sys_func_rval;
 817                 else
 818                         sys_res = tcp->s_ent->sys_func(tcp);
 819         }
 820
 821         tprints(") ");
 822         tabto();
 823         unsigned long u_error = tcp->u_error;
 824
 825         if (raw(tcp)) {
 826                 if (u_error) {
 827                         tprintf("= -1 (errno %lu)", u_error);
 828                 } else {
 829                         tprintf("= %#" PRI_klx, tcp->u_rval);
 830                 }
 831                 if (syscall_tampered(tcp))
 832                         tprints(" (INJECTED)");
 833         } else if (!(sys_res & RVAL_NONE) && u_error) {
 834                 const char *u_error_str;
 835
 836                 switch (u_error) {
 837                 /* Blocked signals do not interrupt any syscalls.
 838                  * In this case syscalls don't return ERESTARTfoo codes.
 839                  *
 840                  * Deadly signals set to SIG_DFL interrupt syscalls
 841                  * and kill the process regardless of which of the codes below
 842                  * is returned by the interrupted syscall.
 843                  * In some cases, kernel forces a kernel-generated deadly
 844                  * signal to be unblocked and set to SIG_DFL (and thus cause
 845                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
 846                  * or SIGILL. (The alternative is to leave process spinning
 847                  * forever on the faulty instruction - not useful).
 848                  *
 849                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
 850                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
 851                  * but kernel will always restart them.
 852                  */
 853                 case ERESTARTSYS:
 854                         /* Most common type of signal-interrupted syscall exit code.
 855                          * The system call will be restarted with the same arguments
 856                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
 857                          */
 858                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
 859                         break;
 860                 case ERESTARTNOINTR:
 861                         /* Rare. For example, fork() returns this if interrupted.
 862                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
 863                          */
 864                         tprints("= ? ERESTARTNOINTR (To be restarted)");
 865                         break;
 866                 case ERESTARTNOHAND:
 867                         /* pause(), rt_sigsuspend() etc use this code.
 868                          * SA_RESTART is ignored (assumed not set):
 869                          * syscall won't restart (will return EINTR instead)
 870                          * even after signal with SA_RESTART set. However,
 871                          * after SIG_IGN or SIG_DFL signal it will restart
 872                          * (thus the name "restart only if has no handler").
 873                          */
 874                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
 875                         break;
 876                 case ERESTART_RESTARTBLOCK:
 877                         /* Syscalls like nanosleep(), poll() which can't be
 878                          * restarted with their original arguments use this
 879                          * code. Kernel will execute restart_syscall() instead,
 880                          * which changes arguments before restarting syscall.
 881                          * SA_RESTART is ignored (assumed not set) similarly
 882                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
 883                          * since restart data is saved in "restart block"
 884                          * in task struct, and if signal handler uses a syscall
 885                          * which in turn saves another such restart block,
 886                          * old data is lost and restart becomes impossible)
 887                          */
 888                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
 889                         break;
 890                 default:
 891                         u_error_str = err_name(u_error);
 892                         if (u_error_str)
 893                                 tprintf("= %" PRI_kld " %s (%s)", tcp->u_rval,
 894                                         u_error_str, strerror(u_error));
 895                         else
 896                                 tprintf("= %" PRI_kld " %lu (%s)", tcp->u_rval,
 897                                         u_error, strerror(u_error));
 898                         break;
 899                 }
 900                 if (syscall_tampered(tcp))
 901                         tprints(" (INJECTED)");
 902                 if ((sys_res & RVAL_STR) && tcp->auxstr)
 903                         tprintf(" (%s)", tcp->auxstr);
 904         } else {
 905                 if (sys_res & RVAL_NONE)
 906                         tprints("= ?");
 907                 else {
 908                         switch (sys_res & RVAL_MASK) {
 909                         case RVAL_HEX:
 910 #if ANY_WORDSIZE_LESS_THAN_KERNEL_LONG
 911                                 if (current_klongsize < sizeof(tcp->u_rval)) {
 912                                         tprintf("= %#x",
 913                                                 (unsigned int) tcp->u_rval);
 914                                 } else
 915 #endif
 916                                 {
 917                                         tprintf("= %#" PRI_klx, tcp->u_rval);
 918                                 }
 919                                 break;
 920                         case RVAL_OCTAL:
 921                                 tprints("= ");
 922                                 print_numeric_long_umask(tcp->u_rval);
 923                                 break;
 924                         case RVAL_UDECIMAL:
 925 #if ANY_WORDSIZE_LESS_THAN_KERNEL_LONG
 926                                 if (current_klongsize < sizeof(tcp->u_rval)) {
 927                                         tprintf("= %u",
 928                                                 (unsigned int) tcp->u_rval);
 929                                 } else
 930 #endif
 931                                 {
 932                                         tprintf("= %" PRI_klu, tcp->u_rval);
 933                                 }
 934                                 break;
 935                         case RVAL_FD:
 936                                 if (show_fd_path) {
 937                                         tprints("= ");
 938                                         printfd(tcp, tcp->u_rval);
 939                                 } else
 940                                         tprintf("= %" PRI_kld, tcp->u_rval);
 941                                 break;
 942                         default:
 943                                 error_msg("invalid rval format");
 944                                 break;
 945                         }
 946                 }
 947                 if ((sys_res & RVAL_STR) && tcp->auxstr)
 948                         tprintf(" (%s)", tcp->auxstr);
 949                 if (syscall_tampered(tcp))
 950                         tprints(" (INJECTED)");
 951         }
 952         if (Tflag) {
 953                 ts_sub(ts, ts, &tcp->etime);
 954                 tprintf(" <%ld.%06ld>",
 955                         (long) ts->tv_sec, (long) ts->tv_nsec / 1000);
 956         }
 957         tprints("\n");
 958         dumpio(tcp);
 959         line_ended();
 960
 961 #ifdef USE_LIBUNWIND
 962         if (stack_trace_enabled)
 963                 unwind_print_stacktrace(tcp);
 964 #endif
 965         return 0;
 966 }
 967
 968 void
 969 syscall_exiting_finish(struct tcb *tcp)
 970 {
 971         tcp->flags &= ~(TCB_INSYSCALL | TCB_TAMPERED | TCB_INJECT_DELAY_EXIT);
 972         tcp->sys_func_rval = 0;
 973         free_tcb_priv_data(tcp);
 974 }
 975
 976 bool
 977 is_erestart(struct tcb *tcp)
 978 {
 979         switch (tcp->u_error) {
 980                 case ERESTARTSYS:
 981                 case ERESTARTNOINTR:
 982                 case ERESTARTNOHAND:
 983                 case ERESTART_RESTARTBLOCK:
 984                         return true;
 985                 default:
 986                         return false;
 987         }
 988 }
 989
 990 static unsigned long saved_u_error;
 991
 992 void
 993 temporarily_clear_syserror(struct tcb *tcp)
 994 {
 995         saved_u_error = tcp->u_error;
 996         tcp->u_error = 0;
 997 }
 998
 999 void
1000 restore_cleared_syserror(struct tcb *tcp)
1001 {
1002         tcp->u_error = saved_u_error;
1003 }
1004
1005 #include "arch_regs.c"
1006
1007 #if HAVE_ARCH_GETRVAL2
1008 # include "arch_getrval2.c"
1009 #endif
1010
1011 void
1012 print_pc(struct tcb *tcp)
1013 {
1014 #if defined ARCH_PC_REG
1015 # define ARCH_GET_PC 0
1016 #elif defined ARCH_PC_PEEK_ADDR
1017         kernel_ulong_t pc;
1018 # define ARCH_PC_REG pc
1019 # define ARCH_GET_PC upeek(tcp, ARCH_PC_PEEK_ADDR, &pc)
1020 #else
1021 # error Neither ARCH_PC_REG nor ARCH_PC_PEEK_ADDR is defined
1022 #endif
1023         if (get_regs(tcp) < 0 || ARCH_GET_PC)
1024                 tprints(current_wordsize == 4 ? "[????????] "
1025                                               : "[????????????????] ");
1026         else
1027                 tprintf(current_wordsize == 4
1028                         ? "[%08" PRI_klx "] " : "[%016" PRI_klx "] ",
1029                         (kernel_ulong_t) ARCH_PC_REG);
1030 }
1031
1032 #include "getregs_old.h"
1033
1034 #undef ptrace_getregset_or_getregs
1035 #undef ptrace_setregset_or_setregs
1036 #ifdef ARCH_REGS_FOR_GETREGSET
1037
1038 # define ptrace_getregset_or_getregs ptrace_getregset
1039 static long
1040 ptrace_getregset(pid_t pid)
1041 {
1042 # ifdef ARCH_IOVEC_FOR_GETREGSET
1043         /* variable iovec */
1044         ARCH_IOVEC_FOR_GETREGSET.iov_len = sizeof(ARCH_REGS_FOR_GETREGSET);
1045         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS,
1046                       &ARCH_IOVEC_FOR_GETREGSET);
1047 # else
1048         /* constant iovec */
1049         static struct iovec io = {
1050                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1051                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1052         };
1053         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1054
1055 # endif
1056 }
1057
1058 # ifndef HAVE_GETREGS_OLD
1059 #  define ptrace_setregset_or_setregs ptrace_setregset
1060 static int
1061 ptrace_setregset(pid_t pid)
1062 {
1063 #  ifdef ARCH_IOVEC_FOR_GETREGSET
1064         /* variable iovec */
1065         return ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS,
1066                       &ARCH_IOVEC_FOR_GETREGSET);
1067 #  else
1068         /* constant iovec */
1069         static struct iovec io = {
1070                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1071                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1072         };
1073         return ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS, &io);
1074 #  endif
1075 }
1076 # endif /* !HAVE_GETREGS_OLD */
1077
1078 #elif defined ARCH_REGS_FOR_GETREGS
1079
1080 # define ptrace_getregset_or_getregs ptrace_getregs
1081 static long
1082 ptrace_getregs(pid_t pid)
1083 {
1084 # if defined SPARC || defined SPARC64
1085         /* SPARC systems have the meaning of data and addr reversed */
1086         return ptrace(PTRACE_GETREGS, pid, (void *) &ARCH_REGS_FOR_GETREGS, 0);
1087 # else
1088         return ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1089 # endif
1090 }
1091
1092 # ifndef HAVE_GETREGS_OLD
1093 #  define ptrace_setregset_or_setregs ptrace_setregs
1094 static int
1095 ptrace_setregs(pid_t pid)
1096 {
1097 #  if defined SPARC || defined SPARC64
1098         /* SPARC systems have the meaning of data and addr reversed */
1099         return ptrace(PTRACE_SETREGS, pid, (void *) &ARCH_REGS_FOR_GETREGS, 0);
1100 #  else
1101         return ptrace(PTRACE_SETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1102 #  endif
1103 }
1104 # endif /* !HAVE_GETREGS_OLD */
1105
1106 #endif /* ARCH_REGS_FOR_GETREGSET || ARCH_REGS_FOR_GETREGS */
1107
1108 #ifdef ptrace_getregset_or_getregs
1109 static long get_regs_error;
1110 #endif
1111
1112 void
1113 clear_regs(struct tcb *tcp)
1114 {
1115 #ifdef ptrace_getregset_or_getregs
1116         get_regs_error = -1;
1117 #endif
1118 }
1119
1120 static long
1121 get_regs(struct tcb *const tcp)
1122 {
1123 #ifdef ptrace_getregset_or_getregs
1124
1125         if (get_regs_error != -1)
1126                 return get_regs_error;
1127
1128 # ifdef HAVE_GETREGS_OLD
1129         /*
1130          * Try PTRACE_GETREGSET/PTRACE_GETREGS first,
1131          * fallback to getregs_old.
1132          */
1133         static int use_getregs_old;
1134         if (use_getregs_old < 0) {
1135                 return get_regs_error = ptrace_getregset_or_getregs(tcp->pid);
1136         } else if (use_getregs_old == 0) {
1137                 get_regs_error = ptrace_getregset_or_getregs(tcp->pid);
1138                 if (get_regs_error >= 0) {
1139                         use_getregs_old = -1;
1140                         return get_regs_error;
1141                 }
1142                 if (errno == EPERM || errno == ESRCH)
1143                         return get_regs_error;
1144                 use_getregs_old = 1;
1145         }
1146         return get_regs_error = getregs_old(tcp);
1147 # else /* !HAVE_GETREGS_OLD */
1148         /* Assume that PTRACE_GETREGSET/PTRACE_GETREGS works. */
1149         get_regs_error = ptrace_getregset_or_getregs(tcp->pid);
1150
1151 #  if defined ARCH_PERSONALITY_0_IOV_SIZE
1152         if (get_regs_error)
1153                 return get_regs_error;
1154
1155         switch (ARCH_IOVEC_FOR_GETREGSET.iov_len) {
1156         case ARCH_PERSONALITY_0_IOV_SIZE:
1157                 update_personality(tcp, 0);
1158                 break;
1159         case ARCH_PERSONALITY_1_IOV_SIZE:
1160                 update_personality(tcp, 1);
1161                 break;
1162         default: {
1163                 static bool printed = false;
1164
1165                 if (!printed) {
1166                         error_msg("Unsupported regset size returned by "
1167                                   "PTRACE_GETREGSET: %zu",
1168                                   ARCH_IOVEC_FOR_GETREGSET.iov_len);
1169
1170                         printed = true;
1171                 }
1172
1173                 update_personality(tcp, 0);
1174         }
1175         }
1176 #  endif /* ARCH_PERSONALITY_0_IOV_SIZE */
1177
1178         return get_regs_error;
1179
1180 # endif /* !HAVE_GETREGS_OLD */
1181
1182 #else /* !ptrace_getregset_or_getregs */
1183
1184 # warning get_regs is not implemented for this architecture yet
1185         return 0;
1186
1187 #endif /* !ptrace_getregset_or_getregs */
1188 }
1189
1190 #ifdef ptrace_setregset_or_setregs
1191 static int
1192 set_regs(pid_t pid)
1193 {
1194         return ptrace_setregset_or_setregs(pid);
1195 }
1196 #endif /* ptrace_setregset_or_setregs */
1197
1198 struct sysent_buf {
1199         struct tcb *tcp;
1200         struct_sysent ent;
1201         char buf[sizeof("syscall_0x") + sizeof(kernel_ulong_t) * 2];
1202 };
1203
1204 static void
1205 free_sysent_buf(void *ptr)
1206 {
1207         struct sysent_buf *s = ptr;
1208         s->tcp->s_prev_ent = s->tcp->s_ent = NULL;
1209         free(ptr);
1210 }
1211
1212 /*
1213  * Returns:
1214  * 0: "ignore this ptrace stop", syscall_entering_decode() should return a "bail
1215  *    out silently" code.
1216  * 1: ok, continue in syscall_entering_decode().
1217  * other: error, syscall_entering_decode() should print error indicator
1218  *    ("????" etc) and return an appropriate code.
1219  */
1220 int
1221 get_scno(struct tcb *tcp)
1222 {
1223         if (get_regs(tcp) < 0)
1224                 return -1;
1225
1226         int rc = arch_get_scno(tcp);
1227         if (rc != 1)
1228                 return rc;
1229
1230         tcp->scno = shuffle_scno(tcp->scno);
1231
1232         if (scno_is_valid(tcp->scno)) {
1233                 tcp->s_ent = &sysent[tcp->scno];
1234                 tcp->qual_flg = qual_flags(tcp->scno);
1235         } else {
1236                 struct sysent_buf *s = xcalloc(1, sizeof(*s));
1237
1238                 s->tcp = tcp;
1239                 s->ent.nargs = MAX_ARGS;
1240                 s->ent.sen = SEN_printargs;
1241                 s->ent.sys_func = printargs;
1242                 s->ent.sys_name = s->buf;
1243                 xsprintf(s->buf, "syscall_%#" PRI_klx, shuffle_scno(tcp->scno));
1244
1245                 tcp->s_ent = &s->ent;
1246                 tcp->qual_flg = QUAL_RAW | DEFAULT_QUAL_FLAGS;
1247
1248                 set_tcb_priv_data(tcp, s, free_sysent_buf);
1249
1250                 debug_msg("pid %d invalid syscall %#" PRI_klx,
1251                           tcp->pid, shuffle_scno(tcp->scno));
1252         }
1253
1254         /*
1255          * We refrain from argument decoding during recovering
1256          * as tracee memory mappings has changed and the registers
1257          * are very likely pointing to garbage already.
1258          */
1259         if (recovering(tcp))
1260                 tcp->qual_flg |= QUAL_RAW;
1261
1262         return 1;
1263 }
1264
1265 #ifdef ptrace_getregset_or_getregs
1266 # define get_syscall_result_regs get_regs
1267 #else
1268 static int get_syscall_result_regs(struct tcb *);
1269 #endif
1270
1271 /* Returns:
1272  * 1: ok, continue in syscall_exiting_trace().
1273  * -1: error, syscall_exiting_trace() should print error indicator
1274  *    ("????" etc) and bail out.
1275  */
1276 static int
1277 get_syscall_result(struct tcb *tcp)
1278 {
1279         if (get_syscall_result_regs(tcp) < 0)
1280                 return -1;
1281         tcp->u_error = 0;
1282         get_error(tcp,
1283                   !(tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS)
1284                         || syscall_tampered(tcp));
1285
1286         return 1;
1287 }
1288
1289 #include "get_scno.c"
1290 #include "set_scno.c"
1291 #include "get_syscall_args.c"
1292 #ifndef ptrace_getregset_or_getregs
1293 # include "get_syscall_result.c"
1294 #endif
1295 #include "get_error.c"
1296 #include "set_error.c"
1297 #ifdef HAVE_GETREGS_OLD
1298 # include "getregs_old.c"
1299 #endif
1300 #include "shuffle_scno.c"
1301
1302 const char *
1303 syscall_name(kernel_ulong_t scno)
1304 {
1305         return scno_is_valid(scno) ? sysent[scno].sys_name : NULL;
1306 }