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