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  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. The name of the author may not be used to endorse or promote products
  20  *    derived from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include "defs.h"
  35 #include "native_defs.h"
  36 #include "nsig.h"
  37 #include <sys/param.h>
  38
  39 /* for struct iovec */
  40 #include <sys/uio.h>
  41
  42 /* for __X32_SYSCALL_BIT */
  43 #include <asm/unistd.h>
  44
  45 #include "regs.h"
  46 #include "ptrace.h"
  47
  48 #if defined(SPARC64)
  49 # undef PTRACE_GETREGS
  50 # define PTRACE_GETREGS PTRACE_GETREGS64
  51 # undef PTRACE_SETREGS
  52 # define PTRACE_SETREGS PTRACE_SETREGS64
  53 #endif
  54
  55 #if defined SPARC64
  56 # include <asm/psrcompat.h>
  57 #elif defined SPARC
  58 # include <asm/psr.h>
  59 #endif
  60
  61 #ifdef IA64
  62 # include <asm/rse.h>
  63 #endif
  64
  65 #ifndef NT_PRSTATUS
  66 # define NT_PRSTATUS 1
  67 #endif
  68
  69 #include "syscall.h"
  70
  71 /* Define these shorthand notations to simplify the syscallent files. */
  72 #define TD TRACE_DESC
  73 #define TF TRACE_FILE
  74 #define TI TRACE_IPC
  75 #define TN TRACE_NETWORK
  76 #define TP TRACE_PROCESS
  77 #define TS TRACE_SIGNAL
  78 #define TM TRACE_MEMORY
  79 #define TST TRACE_STAT
  80 #define TLST TRACE_LSTAT
  81 #define TFST TRACE_FSTAT
  82 #define TSTA TRACE_STAT_LIKE
  83 #define TSF TRACE_STATFS
  84 #define TFSF TRACE_FSTATFS
  85 #define TSFA TRACE_STATFS_LIKE
  86 #define NF SYSCALL_NEVER_FAILS
  87 #define MA MAX_ARGS
  88 #define SI STACKTRACE_INVALIDATE_CACHE
  89 #define SE STACKTRACE_CAPTURE_ON_ENTER
  90 #define CST COMPAT_SYSCALL_TYPES
  91
  92 #define SEN(syscall_name) SEN_ ## syscall_name, SYS_FUNC_NAME(sys_ ## syscall_name)
  93
  94 const struct_sysent sysent0[] = {
  95 #include "syscallent.h"
  96 };
  97
  98 #if SUPPORTED_PERSONALITIES > 1
  99 # include PERSONALITY1_INCLUDE_FUNCS
 100 static const struct_sysent sysent1[] = {
 101 # include "syscallent1.h"
 102 };
 103 #endif
 104
 105 #if SUPPORTED_PERSONALITIES > 2
 106 # include PERSONALITY2_INCLUDE_FUNCS
 107 static const struct_sysent sysent2[] = {
 108 # include "syscallent2.h"
 109 };
 110 #endif
 111
 112 /* Now undef them since short defines cause wicked namespace pollution. */
 113 #undef SEN
 114 #undef TD
 115 #undef TF
 116 #undef TI
 117 #undef TN
 118 #undef TP
 119 #undef TS
 120 #undef TM
 121 #undef TST
 122 #undef TLST
 123 #undef TFST
 124 #undef TSTA
 125 #undef TSF
 126 #undef TFSF
 127 #undef TSFA
 128 #undef NF
 129 #undef MA
 130 #undef SI
 131 #undef SE
 132 #undef CST
 133
 134 /*
 135  * `ioctlent[012].h' files are automatically generated by the auxiliary
 136  * program `ioctlsort', such that the list is sorted by the `code' field.
 137  * This has the side-effect of resolving the _IO.. macros into
 138  * plain integers, eliminating the need to include here everything
 139  * in "/usr/include".
 140  */
 141
 142 const char *const errnoent0[] = {
 143 #include "errnoent.h"
 144 };
 145 const char *const signalent0[] = {
 146 #include "signalent.h"
 147 };
 148 const struct_ioctlent ioctlent0[] = {
 149 #include "ioctlent0.h"
 150 };
 151
 152 #if SUPPORTED_PERSONALITIES > 1
 153 static const char *const errnoent1[] = {
 154 # include "errnoent1.h"
 155 };
 156 static const char *const signalent1[] = {
 157 # include "signalent1.h"
 158 };
 159 static const struct_ioctlent ioctlent1[] = {
 160 # include "ioctlent1.h"
 161 };
 162 # include PERSONALITY0_INCLUDE_PRINTERS_DECLS
 163 static const struct_printers printers0 = {
 164 # include PERSONALITY0_INCLUDE_PRINTERS_DEFS
 165 };
 166 # include PERSONALITY1_INCLUDE_PRINTERS_DECLS
 167 static const struct_printers printers1 = {
 168 # include PERSONALITY1_INCLUDE_PRINTERS_DEFS
 169 };
 170 #endif
 171
 172 #if SUPPORTED_PERSONALITIES > 2
 173 static const char *const errnoent2[] = {
 174 # include "errnoent2.h"
 175 };
 176 static const char *const signalent2[] = {
 177 # include "signalent2.h"
 178 };
 179 static const struct_ioctlent ioctlent2[] = {
 180 # include "ioctlent2.h"
 181 };
 182 # include PERSONALITY2_INCLUDE_PRINTERS_DECLS
 183 static const struct_printers printers2 = {
 184 # include PERSONALITY2_INCLUDE_PRINTERS_DEFS
 185 };
 186 #endif
 187
 188 enum {
 189         nsyscalls0 = ARRAY_SIZE(sysent0)
 190 #if SUPPORTED_PERSONALITIES > 1
 191         , nsyscalls1 = ARRAY_SIZE(sysent1)
 192 # if SUPPORTED_PERSONALITIES > 2
 193         , nsyscalls2 = ARRAY_SIZE(sysent2)
 194 # endif
 195 #endif
 196 };
 197
 198 enum {
 199         nerrnos0 = ARRAY_SIZE(errnoent0)
 200 #if SUPPORTED_PERSONALITIES > 1
 201         , nerrnos1 = ARRAY_SIZE(errnoent1)
 202 # if SUPPORTED_PERSONALITIES > 2
 203         , nerrnos2 = ARRAY_SIZE(errnoent2)
 204 # endif
 205 #endif
 206 };
 207
 208 enum {
 209         nsignals0 = ARRAY_SIZE(signalent0)
 210 #if SUPPORTED_PERSONALITIES > 1
 211         , nsignals1 = ARRAY_SIZE(signalent1)
 212 # if SUPPORTED_PERSONALITIES > 2
 213         , nsignals2 = ARRAY_SIZE(signalent2)
 214 # endif
 215 #endif
 216 };
 217
 218 enum {
 219         nioctlents0 = ARRAY_SIZE(ioctlent0)
 220 #if SUPPORTED_PERSONALITIES > 1
 221         , nioctlents1 = ARRAY_SIZE(ioctlent1)
 222 # if SUPPORTED_PERSONALITIES > 2
 223         , nioctlents2 = ARRAY_SIZE(ioctlent2)
 224 # endif
 225 #endif
 226 };
 227
 228 #if SUPPORTED_PERSONALITIES > 1
 229 const struct_sysent *sysent = sysent0;
 230 const char *const *errnoent = errnoent0;
 231 const char *const *signalent = signalent0;
 232 const struct_ioctlent *ioctlent = ioctlent0;
 233 const struct_printers *printers = &printers0;
 234 #endif
 235
 236 unsigned nsyscalls = nsyscalls0;
 237 unsigned nerrnos = nerrnos0;
 238 unsigned nsignals = nsignals0;
 239 unsigned nioctlents = nioctlents0;
 240
 241 const unsigned int nsyscall_vec[SUPPORTED_PERSONALITIES] = {
 242         nsyscalls0,
 243 #if SUPPORTED_PERSONALITIES > 1
 244         nsyscalls1,
 245 #endif
 246 #if SUPPORTED_PERSONALITIES > 2
 247         nsyscalls2,
 248 #endif
 249 };
 250 const struct_sysent *const sysent_vec[SUPPORTED_PERSONALITIES] = {
 251         sysent0,
 252 #if SUPPORTED_PERSONALITIES > 1
 253         sysent1,
 254 #endif
 255 #if SUPPORTED_PERSONALITIES > 2
 256         sysent2,
 257 #endif
 258 };
 259
 260 #if SUPPORTED_PERSONALITIES > 1
 261 unsigned current_personality;
 262
 263 # ifndef current_wordsize
 264 unsigned current_wordsize;
 265 static const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
 266         PERSONALITY0_WORDSIZE,
 267         PERSONALITY1_WORDSIZE,
 268 # if SUPPORTED_PERSONALITIES > 2
 269         PERSONALITY2_WORDSIZE,
 270 # endif
 271 };
 272 # endif
 273
 274 # ifndef current_klongsize
 275 unsigned current_klongsize;
 276 static const int personality_klongsize[SUPPORTED_PERSONALITIES] = {
 277         PERSONALITY0_KLONGSIZE,
 278         PERSONALITY1_KLONGSIZE,
 279 #  if SUPPORTED_PERSONALITIES > 2
 280         PERSONALITY2_KLONGSIZE,
 281 #  endif
 282 };
 283 # endif
 284
 285 void
 286 set_personality(int personality)
 287 {
 288         nsyscalls = nsyscall_vec[personality];
 289         sysent = sysent_vec[personality];
 290
 291         switch (personality) {
 292         case 0:
 293                 errnoent = errnoent0;
 294                 nerrnos = nerrnos0;
 295                 ioctlent = ioctlent0;
 296                 nioctlents = nioctlents0;
 297                 signalent = signalent0;
 298                 nsignals = nsignals0;
 299                 printers = &printers0;
 300                 break;
 301
 302         case 1:
 303                 errnoent = errnoent1;
 304                 nerrnos = nerrnos1;
 305                 ioctlent = ioctlent1;
 306                 nioctlents = nioctlents1;
 307                 signalent = signalent1;
 308                 nsignals = nsignals1;
 309                 printers = &printers1;
 310                 break;
 311
 312 # if SUPPORTED_PERSONALITIES > 2
 313         case 2:
 314                 errnoent = errnoent2;
 315                 nerrnos = nerrnos2;
 316                 ioctlent = ioctlent2;
 317                 nioctlents = nioctlents2;
 318                 signalent = signalent2;
 319                 nsignals = nsignals2;
 320                 printers = &printers2;
 321                 break;
 322 # endif
 323         }
 324
 325         current_personality = personality;
 326 # ifndef current_wordsize
 327         current_wordsize = personality_wordsize[personality];
 328 # endif
 329 # ifndef current_klongsize
 330         current_klongsize = personality_klongsize[personality];
 331 # endif
 332 }
 333
 334 static void
 335 update_personality(struct tcb *tcp, unsigned int personality)
 336 {
 337         if (personality == current_personality)
 338                 return;
 339         set_personality(personality);
 340
 341         if (personality == tcp->currpers)
 342                 return;
 343         tcp->currpers = personality;
 344
 345 # undef PERSONALITY_NAMES
 346 # if defined POWERPC64
 347 #  define PERSONALITY_NAMES {"64 bit", "32 bit"}
 348 # elif defined X86_64
 349 #  define PERSONALITY_NAMES {"64 bit", "32 bit", "x32"}
 350 # elif defined X32
 351 #  define PERSONALITY_NAMES {"x32", "32 bit"}
 352 # elif defined AARCH64
 353 #  define PERSONALITY_NAMES {"64 bit", "32 bit"}
 354 # elif defined TILE
 355 #  define PERSONALITY_NAMES {"64-bit", "32-bit"}
 356 # endif
 357 # ifdef PERSONALITY_NAMES
 358         if (!qflag) {
 359                 static const char *const names[] = PERSONALITY_NAMES;
 360                 error_msg("[ Process PID=%d runs in %s mode. ]",
 361                           tcp->pid, names[personality]);
 362         }
 363 # endif
 364 }
 365 #endif
 366
 367 #ifdef SYS_socket_subcall
 368 static void
 369 decode_socket_subcall(struct tcb *tcp)
 370 {
 371         const int call = tcp->u_arg[0];
 372
 373         if (call < 1 || call >= SYS_socket_nsubcalls)
 374                 return;
 375
 376         const kernel_ulong_t scno = SYS_socket_subcall + call;
 377         const unsigned int nargs = sysent[scno].nargs;
 378         uint64_t buf[nargs];
 379
 380         if (umoven(tcp, tcp->u_arg[1], nargs * current_wordsize, buf) < 0)
 381                 return;
 382
 383         tcp->scno = scno;
 384         tcp->qual_flg = qual_flags(scno);
 385         tcp->s_ent = &sysent[scno];
 386
 387         unsigned int i;
 388         for (i = 0; i < nargs; ++i)
 389                 tcp->u_arg[i] = (sizeof(uint32_t) == current_wordsize)
 390                                 ? ((uint32_t *) (void *) buf)[i] : buf[i];
 391 }
 392 #endif
 393
 394 #ifdef SYS_ipc_subcall
 395 static void
 396 decode_ipc_subcall(struct tcb *tcp)
 397 {
 398         unsigned int call = tcp->u_arg[0];
 399         const unsigned int version = call >> 16;
 400
 401         if (version) {
 402 # if defined S390 || defined S390X
 403                 return;
 404 # else
 405 #  ifdef SPARC64
 406                 if (current_wordsize == 8)
 407                         return;
 408 #  endif
 409                 set_tcb_priv_ulong(tcp, version);
 410                 call &= 0xffff;
 411 # endif
 412         }
 413
 414         switch (call) {
 415                 case  1: case  2: case  3: case  4:
 416                 case 11: case 12: case 13: case 14:
 417                 case 21: case 22: case 23: case 24:
 418                         break;
 419                 default:
 420                         return;
 421         }
 422
 423         tcp->scno = SYS_ipc_subcall + call;
 424         tcp->qual_flg = qual_flags(tcp->scno);
 425         tcp->s_ent = &sysent[tcp->scno];
 426
 427         const unsigned int n = tcp->s_ent->nargs;
 428         unsigned int i;
 429         for (i = 0; i < n; i++)
 430                 tcp->u_arg[i] = tcp->u_arg[i + 1];
 431 }
 432 #endif
 433
 434 #ifdef LINUX_MIPSO32
 435 static void
 436 decode_mips_subcall(struct tcb *tcp)
 437 {
 438         if (!scno_is_valid(tcp->u_arg[0]))
 439                 return;
 440         tcp->scno = tcp->u_arg[0];
 441         tcp->qual_flg = qual_flags(tcp->scno);
 442         tcp->s_ent = &sysent[tcp->scno];
 443         memmove(&tcp->u_arg[0], &tcp->u_arg[1],
 444                 sizeof(tcp->u_arg) - sizeof(tcp->u_arg[0]));
 445         /*
 446          * Fetching the last arg of 7-arg syscalls (fadvise64_64
 447          * and sync_file_range) requires additional code,
 448          * see linux/mips/get_syscall_args.c
 449          */
 450         if (tcp->s_ent->nargs == MAX_ARGS) {
 451                 if (umoven(tcp,
 452                            mips_REG_SP + MAX_ARGS * sizeof(tcp->u_arg[0]),
 453                            sizeof(tcp->u_arg[0]),
 454                            &tcp->u_arg[MAX_ARGS - 1]) < 0)
 455                 tcp->u_arg[MAX_ARGS - 1] = 0;
 456         }
 457 }
 458 #endif /* LINUX_MIPSO32 */
 459
 460 static void
 461 dumpio(struct tcb *tcp)
 462 {
 463         if (syserror(tcp))
 464                 return;
 465
 466         int fd = tcp->u_arg[0];
 467         if (fd < 0)
 468                 return;
 469
 470         if (is_number_in_set(fd, &read_set)) {
 471                 switch (tcp->s_ent->sen) {
 472                 case SEN_read:
 473                 case SEN_pread:
 474                 case SEN_recv:
 475                 case SEN_recvfrom:
 476                 case SEN_mq_timedreceive:
 477                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
 478                         return;
 479                 case SEN_readv:
 480                 case SEN_preadv:
 481                 case SEN_preadv2:
 482                         dumpiov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1],
 483                                      tcp->u_rval);
 484                         return;
 485                 case SEN_recvmsg:
 486                         dumpiov_in_msghdr(tcp, tcp->u_arg[1], tcp->u_rval);
 487                         return;
 488                 case SEN_recvmmsg:
 489                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 490                         return;
 491                 }
 492         }
 493         if (is_number_in_set(fd, &write_set)) {
 494                 switch (tcp->s_ent->sen) {
 495                 case SEN_write:
 496                 case SEN_pwrite:
 497                 case SEN_send:
 498                 case SEN_sendto:
 499                 case SEN_mq_timedsend:
 500                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
 501                         break;
 502                 case SEN_writev:
 503                 case SEN_pwritev:
 504                 case SEN_pwritev2:
 505                 case SEN_vmsplice:
 506                         dumpiov_upto(tcp, tcp->u_arg[2], tcp->u_arg[1], -1);
 507                         break;
 508                 case SEN_sendmsg:
 509                         dumpiov_in_msghdr(tcp, tcp->u_arg[1], -1);
 510                         break;
 511                 case SEN_sendmmsg:
 512                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
 513                         break;
 514                 }
 515         }
 516 }
 517
 518 /*
 519  * Shuffle syscall numbers so that we don't have huge gaps in syscall table.
 520  * The shuffling should be an involution: shuffle_scno(shuffle_scno(n)) == n.
 521  */
 522 static kernel_ulong_t
 523 shuffle_scno(kernel_ulong_t scno)
 524 {
 525 #if defined(ARM) || defined(AARCH64) /* So far only 32-bit ARM needs this */
 526         if (scno < ARM_FIRST_SHUFFLED_SYSCALL)
 527                 return scno;
 528
 529         /* __ARM_NR_cmpxchg? Swap with LAST_ORDINARY+1 */
 530         if (scno == ARM_FIRST_SHUFFLED_SYSCALL)
 531                 return 0x000ffff0;
 532         if (scno == 0x000ffff0)
 533                 return ARM_FIRST_SHUFFLED_SYSCALL;
 534
 535 # define ARM_SECOND_SHUFFLED_SYSCALL (ARM_FIRST_SHUFFLED_SYSCALL + 1)
 536         /*
 537          * Is it ARM specific syscall?
 538          * Swap [0x000f0000, 0x000f0000 + LAST_SPECIAL] range
 539          * with [SECOND_SHUFFLED, SECOND_SHUFFLED + LAST_SPECIAL] range.
 540          */
 541         if (scno >= 0x000f0000 &&
 542             scno <= 0x000f0000 + ARM_LAST_SPECIAL_SYSCALL) {
 543                 return scno - 0x000f0000 + ARM_SECOND_SHUFFLED_SYSCALL;
 544         }
 545         if (scno <= ARM_SECOND_SHUFFLED_SYSCALL + ARM_LAST_SPECIAL_SYSCALL) {
 546                 return scno + 0x000f0000 - ARM_SECOND_SHUFFLED_SYSCALL;
 547         }
 548 #endif /* ARM || AARCH64 */
 549
 550         return scno;
 551 }
 552
 553 const char *
 554 err_name(unsigned long err)
 555 {
 556         if ((err < nerrnos) && errnoent[err])
 557                 return errnoent[err];
 558
 559         return NULL;
 560 }
 561
 562 static long get_regs_error;
 563
 564 void
 565 clear_regs(void)
 566 {
 567         get_regs_error = -1;
 568 }
 569
 570 static void get_regs(pid_t pid);
 571 static int get_syscall_args(struct tcb *);
 572 static int get_syscall_result(struct tcb *);
 573 static int arch_get_scno(struct tcb *tcp);
 574 static int arch_set_scno(struct tcb *, kernel_ulong_t);
 575 static void get_error(struct tcb *, const bool);
 576 static int arch_set_error(struct tcb *);
 577 static int arch_set_success(struct tcb *);
 578
 579 struct inject_opts *inject_vec[SUPPORTED_PERSONALITIES];
 580
 581 static struct inject_opts *
 582 tcb_inject_opts(struct tcb *tcp)
 583 {
 584         return (scno_in_range(tcp->scno) && tcp->inject_vec[current_personality])
 585                ? &tcp->inject_vec[current_personality][tcp->scno] : NULL;
 586 }
 587
 588
 589 static long
 590 tamper_with_syscall_entering(struct tcb *tcp, unsigned int *signo)
 591 {
 592         if (!tcp->inject_vec[current_personality]) {
 593                 tcp->inject_vec[current_personality] =
 594                         xcalloc(nsyscalls, sizeof(**inject_vec));
 595                 memcpy(tcp->inject_vec[current_personality],
 596                        inject_vec[current_personality],
 597                        nsyscalls * sizeof(**inject_vec));
 598         }
 599
 600         struct inject_opts *opts = tcb_inject_opts(tcp);
 601
 602         if (!opts || opts->first == 0)
 603                 return 0;
 604
 605         --opts->first;
 606
 607         if (opts->first != 0)
 608                 return 0;
 609
 610         opts->first = opts->step;
 611
 612         if (opts->signo > 0)
 613                 *signo = opts->signo;
 614         if (opts->rval != INJECT_OPTS_RVAL_DEFAULT && !arch_set_scno(tcp, -1))
 615                 tcp->flags |= TCB_TAMPERED;
 616
 617         return 0;
 618 }
 619
 620 static long
 621 tamper_with_syscall_exiting(struct tcb *tcp)
 622 {
 623         struct inject_opts *opts = tcb_inject_opts(tcp);
 624
 625         if (!opts)
 626                 return 0;
 627
 628         if (opts->rval >= 0) {
 629                 kernel_long_t u_rval = tcp->u_rval;
 630
 631                 tcp->u_rval = opts->rval;
 632                 if (arch_set_success(tcp)) {
 633                         tcp->u_rval = u_rval;
 634                 } else {
 635                         tcp->u_error = 0;
 636                 }
 637         } else {
 638                 unsigned long new_error = -opts->rval;
 639
 640                 if (new_error != tcp->u_error && new_error <= MAX_ERRNO_VALUE) {
 641                         unsigned long u_error = tcp->u_error;
 642
 643                         tcp->u_error = new_error;
 644                         if (arch_set_error(tcp)) {
 645                                 tcp->u_error = u_error;
 646                         }
 647                 }
 648         }
 649
 650         return 0;
 651 }
 652
 653 static int
 654 trace_syscall_entering(struct tcb *tcp, unsigned int *sig)
 655 {
 656         int res = get_scno(tcp);
 657         if (res == 0)
 658                 return res;
 659
 660         int scno_good = res;
 661         if (res == 1)
 662                 res = get_syscall_args(tcp);
 663
 664         if (res != 1) {
 665                 printleader(tcp);
 666                 tprintf("%s(", scno_good == 1 ? tcp->s_ent->sys_name : "????");
 667                 /*
 668                  * " <unavailable>" will be added later by the code which
 669                  * detects ptrace errors.
 670                  */
 671                 goto ret;
 672         }
 673
 674 #ifdef LINUX_MIPSO32
 675         if (SEN_syscall == tcp->s_ent->sen)
 676                 decode_mips_subcall(tcp);
 677 #endif
 678
 679 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
 680         switch (tcp->s_ent->sen) {
 681 # ifdef SYS_socket_subcall
 682                 case SEN_socketcall:
 683                         decode_socket_subcall(tcp);
 684                         break;
 685 # endif
 686 # ifdef SYS_ipc_subcall
 687                 case SEN_ipc:
 688                         decode_ipc_subcall(tcp);
 689                         break;
 690 # endif
 691         }
 692 #endif
 693
 694         /* Restrain from fault injection while the trace executes strace code. */
 695         if (hide_log(tcp)) {
 696                 tcp->qual_flg &= ~QUAL_INJECT;
 697         }
 698
 699         switch (tcp->s_ent->sen) {
 700                 case SEN_execve:
 701                 case SEN_execveat:
 702 #if defined SPARC || defined SPARC64
 703                 case SEN_execv:
 704 #endif
 705                         tcp->flags &= ~TCB_HIDE_LOG;
 706                         break;
 707         }
 708
 709         if (!(tcp->qual_flg & QUAL_TRACE)
 710          || (tracing_paths && !pathtrace_match(tcp))
 711         ) {
 712                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
 713                 tcp->sys_func_rval = 0;
 714                 return 0;
 715         }
 716
 717         tcp->flags &= ~TCB_FILTERED;
 718
 719         if (hide_log(tcp)) {
 720                 res = 0;
 721                 goto ret;
 722         }
 723
 724         if (tcp->qual_flg & QUAL_INJECT)
 725                 tamper_with_syscall_entering(tcp, sig);
 726
 727         if (cflag == CFLAG_ONLY_STATS) {
 728                 res = 0;
 729                 goto ret;
 730         }
 731
 732 #ifdef USE_LIBUNWIND
 733         if (stack_trace_enabled) {
 734                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
 735                         unwind_capture_stacktrace(tcp);
 736         }
 737 #endif
 738
 739         printleader(tcp);
 740         tprintf("%s(", tcp->s_ent->sys_name);
 741         if (tcp->qual_flg & QUAL_RAW)
 742                 res = printargs(tcp);
 743         else
 744                 res = tcp->s_ent->sys_func(tcp);
 745
 746         fflush(tcp->outf);
 747  ret:
 748         tcp->flags |= TCB_INSYSCALL;
 749         tcp->sys_func_rval = res;
 750         /* Measure the entrance time as late as possible to avoid errors. */
 751         if (Tflag || cflag)
 752                 gettimeofday(&tcp->etime, NULL);
 753         return res;
 754 }
 755
 756 static bool
 757 syscall_tampered(struct tcb *tcp)
 758 {
 759         return tcp->flags & TCB_TAMPERED;
 760 }
 761
 762 static int
 763 trace_syscall_exiting(struct tcb *tcp)
 764 {
 765         struct timeval tv;
 766
 767         /* Measure the exit time as early as possible to avoid errors. */
 768         if ((Tflag || cflag) && !(filtered(tcp) || hide_log(tcp)))
 769                 gettimeofday(&tv, NULL);
 770
 771 #ifdef USE_LIBUNWIND
 772         if (stack_trace_enabled) {
 773                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
 774                         unwind_cache_invalidate(tcp);
 775         }
 776 #endif
 777
 778         if (filtered(tcp) || hide_log(tcp))
 779                 goto ret;
 780
 781         get_regs(tcp->pid);
 782 #if SUPPORTED_PERSONALITIES > 1
 783         update_personality(tcp, tcp->currpers);
 784 #endif
 785         int res = (get_regs_error ? -1 : get_syscall_result(tcp));
 786
 787         if (syserror(tcp) && syscall_tampered(tcp))
 788                 tamper_with_syscall_exiting(tcp);
 789
 790         if (cflag) {
 791                 count_syscall(tcp, &tv);
 792                 if (cflag == CFLAG_ONLY_STATS) {
 793                         goto ret;
 794                 }
 795         }
 796
 797         /* If not in -ff mode, and printing_tcp != tcp,
 798          * then the log currently does not end with output
 799          * of _our syscall entry_, but with something else.
 800          * We need to say which syscall's return is this.
 801          *
 802          * Forced reprinting via TCB_REPRINT is used only by
 803          * "strace -ff -oLOG test/threaded_execve" corner case.
 804          * It's the only case when -ff mode needs reprinting.
 805          */
 806         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
 807                 tcp->flags &= ~TCB_REPRINT;
 808                 printleader(tcp);
 809                 tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
 810         }
 811         printing_tcp = tcp;
 812
 813         tcp->s_prev_ent = NULL;
 814         if (res != 1) {
 815                 /* There was error in one of prior ptrace ops */
 816                 tprints(") ");
 817                 tabto();
 818                 tprints("= ? <unavailable>\n");
 819                 line_ended();
 820                 tcp->flags &= ~(TCB_INSYSCALL | TCB_TAMPERED);
 821                 tcp->sys_func_rval = 0;
 822                 free_tcb_priv_data(tcp);
 823                 return res;
 824         }
 825         tcp->s_prev_ent = tcp->s_ent;
 826
 827         int sys_res = 0;
 828         if (tcp->qual_flg & QUAL_RAW) {
 829                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
 830         } else {
 831         /* FIXME: not_failing_only (IOW, option -z) is broken:
 832          * failure of syscall is known only after syscall return.
 833          * Thus we end up with something like this on, say, ENOENT:
 834          *     open("doesnt_exist", O_RDONLY <unfinished ...>
 835          *     {next syscall decode}
 836          * whereas the intended result is that open(...) line
 837          * is not shown at all.
 838          */
 839                 if (not_failing_only && tcp->u_error)
 840                         goto ret;       /* ignore failed syscalls */
 841                 if (tcp->sys_func_rval & RVAL_DECODED)
 842                         sys_res = tcp->sys_func_rval;
 843                 else
 844                         sys_res = tcp->s_ent->sys_func(tcp);
 845         }
 846
 847         tprints(") ");
 848         tabto();
 849         unsigned long u_error = tcp->u_error;
 850
 851         if (tcp->qual_flg & QUAL_RAW) {
 852                 if (u_error) {
 853                         tprintf("= -1 (errno %lu)", u_error);
 854                 } else {
 855                         tprintf("= %#" PRI_klx, tcp->u_rval);
 856                 }
 857                 if (syscall_tampered(tcp))
 858                         tprints(" (INJECTED)");
 859         }
 860         else if (!(sys_res & RVAL_NONE) && u_error) {
 861                 const char *u_error_str;
 862
 863                 switch (u_error) {
 864                 /* Blocked signals do not interrupt any syscalls.
 865                  * In this case syscalls don't return ERESTARTfoo codes.
 866                  *
 867                  * Deadly signals set to SIG_DFL interrupt syscalls
 868                  * and kill the process regardless of which of the codes below
 869                  * is returned by the interrupted syscall.
 870                  * In some cases, kernel forces a kernel-generated deadly
 871                  * signal to be unblocked and set to SIG_DFL (and thus cause
 872                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
 873                  * or SIGILL. (The alternative is to leave process spinning
 874                  * forever on the faulty instruction - not useful).
 875                  *
 876                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
 877                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
 878                  * but kernel will always restart them.
 879                  */
 880                 case ERESTARTSYS:
 881                         /* Most common type of signal-interrupted syscall exit code.
 882                          * The system call will be restarted with the same arguments
 883                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
 884                          */
 885                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
 886                         break;
 887                 case ERESTARTNOINTR:
 888                         /* Rare. For example, fork() returns this if interrupted.
 889                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
 890                          */
 891                         tprints("= ? ERESTARTNOINTR (To be restarted)");
 892                         break;
 893                 case ERESTARTNOHAND:
 894                         /* pause(), rt_sigsuspend() etc use this code.
 895                          * SA_RESTART is ignored (assumed not set):
 896                          * syscall won't restart (will return EINTR instead)
 897                          * even after signal with SA_RESTART set. However,
 898                          * after SIG_IGN or SIG_DFL signal it will restart
 899                          * (thus the name "restart only if has no handler").
 900                          */
 901                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
 902                         break;
 903                 case ERESTART_RESTARTBLOCK:
 904                         /* Syscalls like nanosleep(), poll() which can't be
 905                          * restarted with their original arguments use this
 906                          * code. Kernel will execute restart_syscall() instead,
 907                          * which changes arguments before restarting syscall.
 908                          * SA_RESTART is ignored (assumed not set) similarly
 909                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
 910                          * since restart data is saved in "restart block"
 911                          * in task struct, and if signal handler uses a syscall
 912                          * which in turn saves another such restart block,
 913                          * old data is lost and restart becomes impossible)
 914                          */
 915                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
 916                         break;
 917                 default:
 918                         u_error_str = err_name(u_error);
 919                         if (u_error_str)
 920                                 tprintf("= -1 %s (%s)",
 921                                         u_error_str, strerror(u_error));
 922                         else
 923                                 tprintf("= -1 %lu (%s)",
 924                                         u_error, strerror(u_error));
 925                         break;
 926                 }
 927                 if (syscall_tampered(tcp))
 928                         tprints(" (INJECTED)");
 929                 if ((sys_res & RVAL_STR) && tcp->auxstr)
 930                         tprintf(" (%s)", tcp->auxstr);
 931         }
 932         else {
 933                 if (sys_res & RVAL_NONE)
 934                         tprints("= ?");
 935                 else {
 936                         switch (sys_res & RVAL_MASK) {
 937                         case RVAL_HEX:
 938 #if ANY_WORDSIZE_LESS_THAN_KERNEL_LONG
 939                                 if (current_wordsize < sizeof(tcp->u_rval)) {
 940                                         tprintf("= %#x",
 941                                                 (unsigned int) tcp->u_rval);
 942                                 } else
 943 #endif
 944                                 {
 945                                         tprintf("= %#" PRI_klx, tcp->u_rval);
 946                                 }
 947                                 break;
 948                         case RVAL_OCTAL:
 949                                 tprints("= ");
 950                                 print_numeric_long_umask(tcp->u_rval);
 951                                 break;
 952                         case RVAL_UDECIMAL:
 953 #if ANY_WORDSIZE_LESS_THAN_KERNEL_LONG
 954                                 if (current_wordsize < sizeof(tcp->u_rval)) {
 955                                         tprintf("= %u",
 956                                                 (unsigned int) tcp->u_rval);
 957                                 } else
 958 #endif
 959                                 {
 960                                         tprintf("= %" PRI_klu, tcp->u_rval);
 961                                 }
 962                                 break;
 963                         case RVAL_DECIMAL:
 964                                 tprintf("= %" PRI_kld, tcp->u_rval);
 965                                 break;
 966                         case RVAL_FD:
 967                                 if (show_fd_path) {
 968                                         tprints("= ");
 969                                         printfd(tcp, tcp->u_rval);
 970                                 }
 971                                 else
 972                                         tprintf("= %" PRI_kld, tcp->u_rval);
 973                                 break;
 974                         default:
 975                                 error_msg("invalid rval format");
 976                                 break;
 977                         }
 978                 }
 979                 if ((sys_res & RVAL_STR) && tcp->auxstr)
 980                         tprintf(" (%s)", tcp->auxstr);
 981                 if (syscall_tampered(tcp))
 982                         tprints(" (INJECTED)");
 983         }
 984         if (Tflag) {
 985                 tv_sub(&tv, &tv, &tcp->etime);
 986                 tprintf(" <%ld.%06ld>",
 987                         (long) tv.tv_sec, (long) tv.tv_usec);
 988         }
 989         tprints("\n");
 990         dumpio(tcp);
 991         line_ended();
 992
 993 #ifdef USE_LIBUNWIND
 994         if (stack_trace_enabled)
 995                 unwind_print_stacktrace(tcp);
 996 #endif
 997
 998  ret:
 999         tcp->flags &= ~(TCB_INSYSCALL | TCB_TAMPERED);
1000         tcp->sys_func_rval = 0;
1001         free_tcb_priv_data(tcp);
1002         return 0;
1003 }
1004
1005 int
1006 trace_syscall(struct tcb *tcp, unsigned int *signo)
1007 {
1008         return exiting(tcp) ?
1009                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp, signo);
1010 }
1011
1012 bool
1013 is_erestart(struct tcb *tcp)
1014 {
1015         switch (tcp->u_error) {
1016                 case ERESTARTSYS:
1017                 case ERESTARTNOINTR:
1018                 case ERESTARTNOHAND:
1019                 case ERESTART_RESTARTBLOCK:
1020                         return true;
1021                 default:
1022                         return false;
1023         }
1024 }
1025
1026 static unsigned long saved_u_error;
1027
1028 void
1029 temporarily_clear_syserror(struct tcb *tcp)
1030 {
1031         saved_u_error = tcp->u_error;
1032         tcp->u_error = 0;
1033 }
1034
1035 void
1036 restore_cleared_syserror(struct tcb *tcp)
1037 {
1038         tcp->u_error = saved_u_error;
1039 }
1040
1041 /*
1042  * Check the syscall return value register value for whether it is
1043  * a negated errno code indicating an error, or a success return value.
1044  */
1045 static inline bool
1046 is_negated_errno(kernel_ulong_t val)
1047 {
1048         /* Linux kernel defines MAX_ERRNO to 4095. */
1049         kernel_ulong_t max = -(kernel_long_t) 4095;
1050
1051 #ifndef current_klongsize
1052         if (current_klongsize < sizeof(val)) {
1053                 val = (uint32_t) val;
1054                 max = (uint32_t) max;
1055         }
1056 #endif /* !current_klongsize */
1057
1058         return val >= max;
1059 }
1060
1061 #include "arch_regs.c"
1062
1063 #ifdef HAVE_GETRVAL2
1064 # include "arch_getrval2.c"
1065 #endif
1066
1067 void
1068 print_pc(struct tcb *tcp)
1069 {
1070 #if defined ARCH_PC_REG
1071 # define ARCH_GET_PC 0
1072 #elif defined ARCH_PC_PEEK_ADDR
1073         kernel_ulong_t pc;
1074 # define ARCH_PC_REG pc
1075 # define ARCH_GET_PC upeek(tcp->pid, ARCH_PC_PEEK_ADDR, &pc)
1076 #else
1077 # error Neither ARCH_PC_REG nor ARCH_PC_PEEK_ADDR is defined
1078 #endif
1079         get_regs(tcp->pid);
1080         if (get_regs_error || ARCH_GET_PC)
1081                 tprints(current_wordsize == 4 ? "[????????] "
1082                                               : "[????????????????] ");
1083         else
1084                 tprintf(current_wordsize == 4
1085                         ? "[%08" PRI_klx "] " : "[%016" PRI_klx "] ",
1086                         (kernel_ulong_t) ARCH_PC_REG);
1087 }
1088
1089 #include "getregs_old.h"
1090
1091 #undef ptrace_getregset_or_getregs
1092 #undef ptrace_setregset_or_setregs
1093 #ifdef ARCH_REGS_FOR_GETREGSET
1094
1095 # define ptrace_getregset_or_getregs ptrace_getregset
1096 static long
1097 ptrace_getregset(pid_t pid)
1098 {
1099 # ifdef ARCH_IOVEC_FOR_GETREGSET
1100         /* variable iovec */
1101         ARCH_IOVEC_FOR_GETREGSET.iov_len = sizeof(ARCH_REGS_FOR_GETREGSET);
1102         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS,
1103                       &ARCH_IOVEC_FOR_GETREGSET);
1104 # else
1105         /* constant iovec */
1106         static struct iovec io = {
1107                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1108                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1109         };
1110         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1111
1112 # endif
1113 }
1114
1115 # ifndef HAVE_GETREGS_OLD
1116 #  define ptrace_setregset_or_setregs ptrace_setregset
1117 static int
1118 ptrace_setregset(pid_t pid)
1119 {
1120 #  ifdef ARCH_IOVEC_FOR_GETREGSET
1121         /* variable iovec */
1122         return ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS,
1123                       &ARCH_IOVEC_FOR_GETREGSET);
1124 #  else
1125         /* constant iovec */
1126         static struct iovec io = {
1127                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1128                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1129         };
1130         return ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS, &io);
1131 #  endif
1132 }
1133 # endif /* !HAVE_GETREGS_OLD */
1134
1135 #elif defined ARCH_REGS_FOR_GETREGS
1136
1137 # define ptrace_getregset_or_getregs ptrace_getregs
1138 static long
1139 ptrace_getregs(pid_t pid)
1140 {
1141 # if defined SPARC || defined SPARC64
1142         /* SPARC systems have the meaning of data and addr reversed */
1143         return ptrace(PTRACE_GETREGS, pid, (void *) &ARCH_REGS_FOR_GETREGS, 0);
1144 # else
1145         return ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1146 # endif
1147 }
1148
1149 # ifndef HAVE_GETREGS_OLD
1150 #  define ptrace_setregset_or_setregs ptrace_setregs
1151 static int
1152 ptrace_setregs(pid_t pid)
1153 {
1154 #  if defined SPARC || defined SPARC64
1155         /* SPARC systems have the meaning of data and addr reversed */
1156         return ptrace(PTRACE_SETREGS, pid, (void *) &ARCH_REGS_FOR_GETREGS, 0);
1157 #  else
1158         return ptrace(PTRACE_SETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1159 #  endif
1160 }
1161 # endif /* !HAVE_GETREGS_OLD */
1162
1163 #endif /* ARCH_REGS_FOR_GETREGSET || ARCH_REGS_FOR_GETREGS */
1164
1165 static void
1166 get_regs(pid_t pid)
1167 {
1168 #undef USE_GET_SYSCALL_RESULT_REGS
1169 #ifdef ptrace_getregset_or_getregs
1170
1171         if (get_regs_error != -1)
1172                 return;
1173
1174 # ifdef HAVE_GETREGS_OLD
1175         /*
1176          * Try PTRACE_GETREGSET/PTRACE_GETREGS first,
1177          * fallback to getregs_old.
1178          */
1179         static int use_getregs_old;
1180         if (use_getregs_old < 0) {
1181                 get_regs_error = ptrace_getregset_or_getregs(pid);
1182                 return;
1183         } else if (use_getregs_old == 0) {
1184                 get_regs_error = ptrace_getregset_or_getregs(pid);
1185                 if (get_regs_error >= 0) {
1186                         use_getregs_old = -1;
1187                         return;
1188                 }
1189                 if (errno == EPERM || errno == ESRCH)
1190                         return;
1191                 use_getregs_old = 1;
1192         }
1193         get_regs_error = getregs_old(pid);
1194 # else /* !HAVE_GETREGS_OLD */
1195         /* Assume that PTRACE_GETREGSET/PTRACE_GETREGS works. */
1196         get_regs_error = ptrace_getregset_or_getregs(pid);
1197 # endif /* !HAVE_GETREGS_OLD */
1198
1199 #else /* !ptrace_getregset_or_getregs */
1200
1201 # define USE_GET_SYSCALL_RESULT_REGS 1
1202 # warning get_regs is not implemented for this architecture yet
1203         get_regs_error = 0;
1204
1205 #endif /* !ptrace_getregset_or_getregs */
1206 }
1207
1208 #ifdef ptrace_setregset_or_setregs
1209 static int
1210 set_regs(pid_t pid)
1211 {
1212         return ptrace_setregset_or_setregs(pid);
1213 }
1214 #endif /* ptrace_setregset_or_setregs */
1215
1216 struct sysent_buf {
1217         struct tcb *tcp;
1218         struct_sysent ent;
1219         char buf[sizeof("syscall_%lu") + sizeof(kernel_ulong_t) * 3];
1220 };
1221
1222 static void
1223 free_sysent_buf(void *ptr)
1224 {
1225         struct sysent_buf *s = ptr;
1226         s->tcp->s_prev_ent = s->tcp->s_ent = NULL;
1227         free(ptr);
1228 }
1229
1230 /*
1231  * Returns:
1232  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1233  * 1: ok, continue in trace_syscall_entering().
1234  * other: error, trace_syscall_entering() should print error indicator
1235  *    ("????" etc) and bail out.
1236  */
1237 int
1238 get_scno(struct tcb *tcp)
1239 {
1240         get_regs(tcp->pid);
1241
1242         if (get_regs_error)
1243                 return -1;
1244
1245         int rc = arch_get_scno(tcp);
1246         if (rc != 1)
1247                 return rc;
1248
1249         if (scno_is_valid(tcp->scno)) {
1250                 tcp->s_ent = &sysent[tcp->scno];
1251                 tcp->qual_flg = qual_flags(tcp->scno);
1252         } else {
1253                 struct sysent_buf *s = xcalloc(1, sizeof(*s));
1254
1255                 s->tcp = tcp;
1256                 s->ent.nargs = MAX_ARGS;
1257                 s->ent.sen = SEN_printargs;
1258                 s->ent.sys_func = printargs;
1259                 s->ent.sys_name = s->buf;
1260                 sprintf(s->buf, "syscall_%" PRI_klu, shuffle_scno(tcp->scno));
1261
1262                 tcp->s_ent = &s->ent;
1263                 tcp->qual_flg = QUAL_RAW | DEFAULT_QUAL_FLAGS;
1264
1265                 set_tcb_priv_data(tcp, s, free_sysent_buf);
1266
1267                 if (debug_flag)
1268                         error_msg("pid %d invalid syscall %" PRI_kld,
1269                                   tcp->pid, tcp->scno);
1270         }
1271         return 1;
1272 }
1273
1274 #ifdef USE_GET_SYSCALL_RESULT_REGS
1275 static int get_syscall_result_regs(struct tcb *);
1276 #endif
1277
1278 /* Returns:
1279  * 1: ok, continue in trace_syscall_exiting().
1280  * -1: error, trace_syscall_exiting() should print error indicator
1281  *    ("????" etc) and bail out.
1282  */
1283 static int
1284 get_syscall_result(struct tcb *tcp)
1285 {
1286 #ifdef USE_GET_SYSCALL_RESULT_REGS
1287         if (get_syscall_result_regs(tcp))
1288                 return -1;
1289 #endif
1290         tcp->u_error = 0;
1291         get_error(tcp, !(tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS));
1292
1293         return 1;
1294 }
1295
1296 #include "get_scno.c"
1297 #include "set_scno.c"
1298 #include "get_syscall_args.c"
1299 #ifdef USE_GET_SYSCALL_RESULT_REGS
1300 # include "get_syscall_result.c"
1301 #endif
1302 #include "get_error.c"
1303 #include "set_error.c"
1304 #ifdef HAVE_GETREGS_OLD
1305 # include "getregs_old.c"
1306 #endif
1307
1308 const char *
1309 syscall_name(kernel_ulong_t scno)
1310 {
1311 #if defined X32_PERSONALITY_NUMBER && defined __X32_SYSCALL_BIT
1312         if (current_personality == X32_PERSONALITY_NUMBER)
1313                 scno &= ~__X32_SYSCALL_BIT;
1314 #endif
1315         return scno_is_valid(scno) ? sysent[scno].sys_name: NULL;
1316 }