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 <sys/param.h>
  37 #include <signal.h>
  38
  39 /* for struct iovec */
  40 #include <sys/uio.h>
  41
  42 #include "regs.h"
  43 #include "ptrace.h"
  44
  45 #if defined(SPARC64)
  46 # undef PTRACE_GETREGS
  47 # define PTRACE_GETREGS PTRACE_GETREGS64
  48 # undef PTRACE_SETREGS
  49 # define PTRACE_SETREGS PTRACE_SETREGS64
  50 #endif
  51
  52 #if defined SPARC64
  53 # include <asm/psrcompat.h>
  54 #elif defined SPARC
  55 # include <asm/psr.h>
  56 #endif
  57
  58 #ifdef IA64
  59 # include <asm/rse.h>
  60 #endif
  61
  62 #ifndef NT_PRSTATUS
  63 # define NT_PRSTATUS 1
  64 #endif
  65
  66 #ifndef NSIG
  67 # warning: NSIG is not defined, using 32
  68 # define NSIG 32
  69 #endif
  70
  71 #include "syscall.h"
  72
  73 /* Define these shorthand notations to simplify the syscallent files. */
  74 #define TD TRACE_DESC
  75 #define TF TRACE_FILE
  76 #define TI TRACE_IPC
  77 #define TN TRACE_NETWORK
  78 #define TP TRACE_PROCESS
  79 #define TS TRACE_SIGNAL
  80 #define TM TRACE_MEMORY
  81 #define NF SYSCALL_NEVER_FAILS
  82 #define MA MAX_ARGS
  83 #define SI STACKTRACE_INVALIDATE_CACHE
  84 #define SE STACKTRACE_CAPTURE_ON_ENTER
  85 #define CST COMPAT_SYSCALL_TYPES
  86
  87 #define SEN(syscall_name) SEN_ ## syscall_name, SYS_FUNC_NAME(sys_ ## syscall_name)
  88
  89 const struct_sysent sysent0[] = {
  90 #include "syscallent.h"
  91 };
  92
  93 #if SUPPORTED_PERSONALITIES > 1
  94 # include PERSONALITY1_INCLUDE_FUNCS
  95 static const struct_sysent sysent1[] = {
  96 # include "syscallent1.h"
  97 };
  98 #endif
  99
 100 #if SUPPORTED_PERSONALITIES > 2
 101 # include PERSONALITY2_INCLUDE_FUNCS
 102 static const struct_sysent sysent2[] = {
 103 # include "syscallent2.h"
 104 };
 105 #endif
 106
 107 /* Now undef them since short defines cause wicked namespace pollution. */
 108 #undef SEN
 109 #undef TD
 110 #undef TF
 111 #undef TI
 112 #undef TN
 113 #undef TP
 114 #undef TS
 115 #undef TM
 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_scno_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], -1UL);
 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_scno_t
 511 shuffle_scno(kernel_scno_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 int get_syscall_args(struct tcb *);
 559 static int get_syscall_result(struct tcb *);
 560 static int arch_get_scno(struct tcb *tcp);
 561 static int arch_set_scno(struct tcb *, kernel_scno_t);
 562 static void get_error(struct tcb *, const bool);
 563 static int arch_set_error(struct tcb *);
 564
 565 struct fault_opts *fault_vec[SUPPORTED_PERSONALITIES];
 566
 567 static struct fault_opts *
 568 tcb_fault_opts(struct tcb *tcp)
 569 {
 570         return (scno_in_range(tcp->scno) && tcp->fault_vec[current_personality])
 571                ? &tcp->fault_vec[current_personality][tcp->scno] : NULL;
 572 }
 573
 574
 575 static long
 576 inject_syscall_fault_entering(struct tcb *tcp)
 577 {
 578         if (!tcp->fault_vec[current_personality]) {
 579                 tcp->fault_vec[current_personality] =
 580                         xcalloc(nsyscalls, sizeof(**fault_vec));
 581                 memcpy(tcp->fault_vec[current_personality],
 582                        fault_vec[current_personality],
 583                        nsyscalls * sizeof(**fault_vec));
 584         }
 585
 586         struct fault_opts *opts = tcb_fault_opts(tcp);
 587
 588         if (!opts || opts->first == 0)
 589                 return 0;
 590
 591         --opts->first;
 592
 593         if (opts->first != 0)
 594                 return 0;
 595
 596         opts->first = opts->step;
 597
 598         if (!arch_set_scno(tcp, -1))
 599                 tcp->flags |= TCB_FAULT_INJ;
 600
 601         return 0;
 602 }
 603
 604 static long
 605 update_syscall_fault_exiting(struct tcb *tcp)
 606 {
 607         struct fault_opts *opts = tcb_fault_opts(tcp);
 608
 609         if (opts && opts->err && tcp->u_error != opts->err) {
 610                 unsigned long u_error = tcp->u_error;
 611                 tcp->u_error = opts->err;
 612                 if (arch_set_error(tcp))
 613                         tcp->u_error = u_error;
 614         }
 615
 616         return 0;
 617 }
 618
 619 static int
 620 trace_syscall_entering(struct tcb *tcp)
 621 {
 622         int res, scno_good;
 623
 624         scno_good = res = get_scno(tcp);
 625         if (res == 0)
 626                 return res;
 627         if (res == 1)
 628                 res = get_syscall_args(tcp);
 629
 630         if (res != 1) {
 631                 printleader(tcp);
 632                 tprintf("%s(", scno_good == 1 ? tcp->s_ent->sys_name : "????");
 633                 /*
 634                  * " <unavailable>" will be added later by the code which
 635                  * detects ptrace errors.
 636                  */
 637                 goto ret;
 638         }
 639
 640 #ifdef LINUX_MIPSO32
 641         if (SEN_syscall == tcp->s_ent->sen)
 642                 decode_mips_subcall(tcp);
 643 #endif
 644
 645 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
 646         switch (tcp->s_ent->sen) {
 647 # ifdef SYS_socket_subcall
 648                 case SEN_socketcall:
 649                         decode_socket_subcall(tcp);
 650                         break;
 651 # endif
 652 # ifdef SYS_ipc_subcall
 653                 case SEN_ipc:
 654                         decode_ipc_subcall(tcp);
 655                         break;
 656 # endif
 657         }
 658 #endif
 659
 660         /* Restrain from fault injection while the trace executes strace code. */
 661         if (hide_log(tcp)) {
 662                 tcp->qual_flg &= ~QUAL_FAULT;
 663         }
 664
 665         switch (tcp->s_ent->sen) {
 666                 case SEN_execve:
 667                 case SEN_execveat:
 668 #if defined SPARC || defined SPARC64
 669                 case SEN_execv:
 670 #endif
 671                         tcp->flags &= ~TCB_HIDE_LOG;
 672                         break;
 673         }
 674
 675         if (!(tcp->qual_flg & QUAL_TRACE)
 676          || (tracing_paths && !pathtrace_match(tcp))
 677         ) {
 678                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
 679                 tcp->sys_func_rval = 0;
 680                 return 0;
 681         }
 682
 683         tcp->flags &= ~TCB_FILTERED;
 684
 685         if (hide_log(tcp)) {
 686                 res = 0;
 687                 goto ret;
 688         }
 689
 690         if (tcp->qual_flg & QUAL_FAULT)
 691                 inject_syscall_fault_entering(tcp);
 692
 693         if (cflag == CFLAG_ONLY_STATS) {
 694                 res = 0;
 695                 goto ret;
 696         }
 697
 698 #ifdef USE_LIBUNWIND
 699         if (stack_trace_enabled) {
 700                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
 701                         unwind_capture_stacktrace(tcp);
 702         }
 703 #endif
 704
 705         printleader(tcp);
 706         tprintf("%s(", tcp->s_ent->sys_name);
 707         if (tcp->qual_flg & QUAL_RAW)
 708                 res = printargs(tcp);
 709         else
 710                 res = tcp->s_ent->sys_func(tcp);
 711
 712         fflush(tcp->outf);
 713  ret:
 714         tcp->flags |= TCB_INSYSCALL;
 715         tcp->sys_func_rval = res;
 716         /* Measure the entrance time as late as possible to avoid errors. */
 717         if (Tflag || cflag)
 718                 gettimeofday(&tcp->etime, NULL);
 719         return res;
 720 }
 721
 722 static bool
 723 syscall_fault_injected(struct tcb *tcp)
 724 {
 725         return tcp->flags & TCB_FAULT_INJ;
 726 }
 727
 728 static int
 729 trace_syscall_exiting(struct tcb *tcp)
 730 {
 731         int sys_res;
 732         struct timeval tv;
 733         int res;
 734         unsigned long u_error;
 735         const char *u_error_str;
 736
 737         /* Measure the exit time as early as possible to avoid errors. */
 738         if (Tflag || cflag)
 739                 gettimeofday(&tv, NULL);
 740
 741 #ifdef USE_LIBUNWIND
 742         if (stack_trace_enabled) {
 743                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
 744                         unwind_cache_invalidate(tcp);
 745         }
 746 #endif
 747
 748 #if SUPPORTED_PERSONALITIES > 1
 749         update_personality(tcp, tcp->currpers);
 750 #endif
 751         res = (get_regs_error ? -1 : get_syscall_result(tcp));
 752         if (filtered(tcp) || hide_log(tcp))
 753                 goto ret;
 754
 755         if (syserror(tcp) && syscall_fault_injected(tcp))
 756                 update_syscall_fault_exiting(tcp);
 757
 758         if (cflag) {
 759                 count_syscall(tcp, &tv);
 760                 if (cflag == CFLAG_ONLY_STATS) {
 761                         goto ret;
 762                 }
 763         }
 764
 765         /* If not in -ff mode, and printing_tcp != tcp,
 766          * then the log currently does not end with output
 767          * of _our syscall entry_, but with something else.
 768          * We need to say which syscall's return is this.
 769          *
 770          * Forced reprinting via TCB_REPRINT is used only by
 771          * "strace -ff -oLOG test/threaded_execve" corner case.
 772          * It's the only case when -ff mode needs reprinting.
 773          */
 774         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
 775                 tcp->flags &= ~TCB_REPRINT;
 776                 printleader(tcp);
 777                 tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
 778         }
 779         printing_tcp = tcp;
 780
 781         tcp->s_prev_ent = NULL;
 782         if (res != 1) {
 783                 /* There was error in one of prior ptrace ops */
 784                 tprints(") ");
 785                 tabto();
 786                 tprints("= ? <unavailable>\n");
 787                 line_ended();
 788                 tcp->flags &= ~(TCB_INSYSCALL | TCB_FAULT_INJ);
 789                 tcp->sys_func_rval = 0;
 790                 free_tcb_priv_data(tcp);
 791                 return res;
 792         }
 793         tcp->s_prev_ent = tcp->s_ent;
 794
 795         sys_res = 0;
 796         if (tcp->qual_flg & QUAL_RAW) {
 797                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
 798         } else {
 799         /* FIXME: not_failing_only (IOW, option -z) is broken:
 800          * failure of syscall is known only after syscall return.
 801          * Thus we end up with something like this on, say, ENOENT:
 802          *     open("doesnt_exist", O_RDONLY <unfinished ...>
 803          *     {next syscall decode}
 804          * whereas the intended result is that open(...) line
 805          * is not shown at all.
 806          */
 807                 if (not_failing_only && tcp->u_error)
 808                         goto ret;       /* ignore failed syscalls */
 809                 if (tcp->sys_func_rval & RVAL_DECODED)
 810                         sys_res = tcp->sys_func_rval;
 811                 else
 812                         sys_res = tcp->s_ent->sys_func(tcp);
 813         }
 814
 815         tprints(") ");
 816         tabto();
 817         u_error = tcp->u_error;
 818
 819         if (tcp->qual_flg & QUAL_RAW) {
 820                 if (u_error) {
 821                         tprintf("= -1 (errno %lu)", u_error);
 822                         if (syscall_fault_injected(tcp))
 823                                 tprints(" (INJECTED)");
 824                 } else {
 825                         tprintf("= %#lx", tcp->u_rval);
 826                 }
 827         }
 828         else if (!(sys_res & RVAL_NONE) && u_error) {
 829                 switch (u_error) {
 830                 /* Blocked signals do not interrupt any syscalls.
 831                  * In this case syscalls don't return ERESTARTfoo codes.
 832                  *
 833                  * Deadly signals set to SIG_DFL interrupt syscalls
 834                  * and kill the process regardless of which of the codes below
 835                  * is returned by the interrupted syscall.
 836                  * In some cases, kernel forces a kernel-generated deadly
 837                  * signal to be unblocked and set to SIG_DFL (and thus cause
 838                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
 839                  * or SIGILL. (The alternative is to leave process spinning
 840                  * forever on the faulty instruction - not useful).
 841                  *
 842                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
 843                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
 844                  * but kernel will always restart them.
 845                  */
 846                 case ERESTARTSYS:
 847                         /* Most common type of signal-interrupted syscall exit code.
 848                          * The system call will be restarted with the same arguments
 849                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
 850                          */
 851                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
 852                         break;
 853                 case ERESTARTNOINTR:
 854                         /* Rare. For example, fork() returns this if interrupted.
 855                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
 856                          */
 857                         tprints("= ? ERESTARTNOINTR (To be restarted)");
 858                         break;
 859                 case ERESTARTNOHAND:
 860                         /* pause(), rt_sigsuspend() etc use this code.
 861                          * SA_RESTART is ignored (assumed not set):
 862                          * syscall won't restart (will return EINTR instead)
 863                          * even after signal with SA_RESTART set. However,
 864                          * after SIG_IGN or SIG_DFL signal it will restart
 865                          * (thus the name "restart only if has no handler").
 866                          */
 867                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
 868                         break;
 869                 case ERESTART_RESTARTBLOCK:
 870                         /* Syscalls like nanosleep(), poll() which can't be
 871                          * restarted with their original arguments use this
 872                          * code. Kernel will execute restart_syscall() instead,
 873                          * which changes arguments before restarting syscall.
 874                          * SA_RESTART is ignored (assumed not set) similarly
 875                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
 876                          * since restart data is saved in "restart block"
 877                          * in task struct, and if signal handler uses a syscall
 878                          * which in turn saves another such restart block,
 879                          * old data is lost and restart becomes impossible)
 880                          */
 881                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
 882                         break;
 883                 default:
 884                         u_error_str = err_name(u_error);
 885                         if (u_error_str)
 886                                 tprintf("= -1 %s (%s)",
 887                                         u_error_str, strerror(u_error));
 888                         else
 889                                 tprintf("= -1 %lu (%s)",
 890                                         u_error, strerror(u_error));
 891                         break;
 892                 }
 893                 if (syscall_fault_injected(tcp))
 894                         tprintf(" (INJECTED)");
 895                 if ((sys_res & RVAL_STR) && tcp->auxstr)
 896                         tprintf(" (%s)", tcp->auxstr);
 897         }
 898         else {
 899                 if (sys_res & RVAL_NONE)
 900                         tprints("= ?");
 901                 else {
 902                         switch (sys_res & RVAL_MASK) {
 903                         case RVAL_HEX:
 904 #if SUPPORTED_PERSONALITIES > 1
 905                                 if (current_wordsize < sizeof(long))
 906                                         tprintf("= %#x",
 907                                                 (unsigned int) tcp->u_rval);
 908                                 else
 909 #endif
 910                                         tprintf("= %#lx", tcp->u_rval);
 911                                 break;
 912                         case RVAL_OCTAL:
 913                                 tprints("= ");
 914                                 print_numeric_long_umask(tcp->u_rval);
 915                                 break;
 916                         case RVAL_UDECIMAL:
 917 #if SUPPORTED_PERSONALITIES > 1
 918                                 if (current_wordsize < sizeof(long))
 919                                         tprintf("= %u",
 920                                                 (unsigned int) tcp->u_rval);
 921                                 else
 922 #endif
 923                                         tprintf("= %lu", tcp->u_rval);
 924                                 break;
 925                         case RVAL_DECIMAL:
 926                                 tprintf("= %ld", tcp->u_rval);
 927                                 break;
 928                         case RVAL_FD:
 929                                 if (show_fd_path) {
 930                                         tprints("= ");
 931                                         printfd(tcp, tcp->u_rval);
 932                                 }
 933                                 else
 934                                         tprintf("= %ld", tcp->u_rval);
 935                                 break;
 936 #if HAVE_STRUCT_TCB_EXT_ARG
 937                         /*
 938                         case RVAL_LHEX:
 939                                 tprintf("= %#llx", tcp->u_lrval);
 940                                 break;
 941                         case RVAL_LOCTAL:
 942                                 tprintf("= %#llo", tcp->u_lrval);
 943                                 break;
 944                         */
 945                         case RVAL_LUDECIMAL:
 946                                 tprintf("= %llu", tcp->u_lrval);
 947                                 break;
 948                         /*
 949                         case RVAL_LDECIMAL:
 950                                 tprintf("= %lld", tcp->u_lrval);
 951                                 break;
 952                         */
 953 #endif /* HAVE_STRUCT_TCB_EXT_ARG */
 954                         default:
 955                                 error_msg("invalid rval format");
 956                                 break;
 957                         }
 958                 }
 959                 if ((sys_res & RVAL_STR) && tcp->auxstr)
 960                         tprintf(" (%s)", tcp->auxstr);
 961         }
 962         if (Tflag) {
 963                 tv_sub(&tv, &tv, &tcp->etime);
 964                 tprintf(" <%ld.%06ld>",
 965                         (long) tv.tv_sec, (long) tv.tv_usec);
 966         }
 967         tprints("\n");
 968         dumpio(tcp);
 969         line_ended();
 970
 971 #ifdef USE_LIBUNWIND
 972         if (stack_trace_enabled)
 973                 unwind_print_stacktrace(tcp);
 974 #endif
 975
 976  ret:
 977         tcp->flags &= ~(TCB_INSYSCALL | TCB_FAULT_INJ);
 978         tcp->sys_func_rval = 0;
 979         free_tcb_priv_data(tcp);
 980         return 0;
 981 }
 982
 983 int
 984 trace_syscall(struct tcb *tcp)
 985 {
 986         return exiting(tcp) ?
 987                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
 988 }
 989
 990 bool
 991 is_erestart(struct tcb *tcp)
 992 {
 993         switch (tcp->u_error) {
 994                 case ERESTARTSYS:
 995                 case ERESTARTNOINTR:
 996                 case ERESTARTNOHAND:
 997                 case ERESTART_RESTARTBLOCK:
 998                         return true;
 999                 default:
1000                         return false;
1001         }
1002 }
1003
1004 static unsigned long saved_u_error;
1005
1006 void
1007 temporarily_clear_syserror(struct tcb *tcp)
1008 {
1009         saved_u_error = tcp->u_error;
1010         tcp->u_error = 0;
1011 }
1012
1013 void
1014 restore_cleared_syserror(struct tcb *tcp)
1015 {
1016         tcp->u_error = saved_u_error;
1017 }
1018
1019 /*
1020  * Check the syscall return value register value for whether it is
1021  * a negated errno code indicating an error, or a success return value.
1022  */
1023 static inline bool
1024 is_negated_errno(kernel_ulong_t val)
1025 {
1026         /* Linux kernel defines MAX_ERRNO to 4095. */
1027         kernel_ulong_t max = -(kernel_long_t) 4095;
1028
1029 #ifndef current_klongsize
1030         if (current_klongsize < sizeof(val)) {
1031                 val = (uint32_t) val;
1032                 max = (uint32_t) max;
1033         }
1034 #endif /* !current_klongsize */
1035
1036         return val >= max;
1037 }
1038
1039 #include "arch_regs.c"
1040
1041 #ifdef HAVE_GETRVAL2
1042 # include "arch_getrval2.c"
1043 #endif
1044
1045 void
1046 print_pc(struct tcb *tcp)
1047 {
1048 #if defined ARCH_PC_REG
1049 # define ARCH_GET_PC 0
1050 #elif defined ARCH_PC_PEEK_ADDR
1051         long pc;
1052 # define ARCH_PC_REG pc
1053 # define ARCH_GET_PC upeek(tcp->pid, ARCH_PC_PEEK_ADDR, &pc)
1054 #else
1055 # error Neither ARCH_PC_REG nor ARCH_PC_PEEK_ADDR is defined
1056 #endif
1057         if (get_regs_error || ARCH_GET_PC)
1058                 tprints(current_wordsize == 4 ? "[????????] "
1059                                               : "[????????????????] ");
1060         else
1061                 tprintf(current_wordsize == 4 ? "[%08lx] " : "[%016lx] ",
1062                         (unsigned long) ARCH_PC_REG);
1063 }
1064
1065 #include "getregs_old.h"
1066
1067 #undef ptrace_getregset_or_getregs
1068 #undef ptrace_setregset_or_setregs
1069 #ifdef ARCH_REGS_FOR_GETREGSET
1070
1071 # define ptrace_getregset_or_getregs ptrace_getregset
1072 static long
1073 ptrace_getregset(pid_t pid)
1074 {
1075 # ifdef ARCH_IOVEC_FOR_GETREGSET
1076         /* variable iovec */
1077         ARCH_IOVEC_FOR_GETREGSET.iov_len = sizeof(ARCH_REGS_FOR_GETREGSET);
1078         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS,
1079                       &ARCH_IOVEC_FOR_GETREGSET);
1080 # else
1081         /* constant iovec */
1082         static struct iovec io = {
1083                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1084                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1085         };
1086         return ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1087
1088 # endif
1089 }
1090
1091 # ifndef HAVE_GETREGS_OLD
1092 #  define ptrace_setregset_or_setregs ptrace_setregset
1093 static int
1094 ptrace_setregset(pid_t pid)
1095 {
1096 #  ifdef ARCH_IOVEC_FOR_GETREGSET
1097         /* variable iovec */
1098         return ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS,
1099                       &ARCH_IOVEC_FOR_GETREGSET);
1100 #  else
1101         /* constant iovec */
1102         static struct iovec io = {
1103                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1104                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1105         };
1106         return ptrace(PTRACE_SETREGSET, pid, NT_PRSTATUS, &io);
1107 #  endif
1108 }
1109 # endif /* !HAVE_GETREGS_OLD */
1110
1111 #elif defined ARCH_REGS_FOR_GETREGS
1112
1113 # define ptrace_getregset_or_getregs ptrace_getregs
1114 static long
1115 ptrace_getregs(pid_t pid)
1116 {
1117 # if defined SPARC || defined SPARC64
1118         /* SPARC systems have the meaning of data and addr reversed */
1119         return ptrace(PTRACE_GETREGS, pid, (void *) &ARCH_REGS_FOR_GETREGS, 0);
1120 # else
1121         return ptrace(PTRACE_GETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1122 # endif
1123 }
1124
1125 # ifndef HAVE_GETREGS_OLD
1126 #  define ptrace_setregset_or_setregs ptrace_setregs
1127 static int
1128 ptrace_setregs(pid_t pid)
1129 {
1130 #  if defined SPARC || defined SPARC64
1131         /* SPARC systems have the meaning of data and addr reversed */
1132         return ptrace(PTRACE_SETREGS, pid, (void *) &ARCH_REGS_FOR_GETREGS, 0);
1133 #  else
1134         return ptrace(PTRACE_SETREGS, pid, NULL, &ARCH_REGS_FOR_GETREGS);
1135 #  endif
1136 }
1137 # endif /* !HAVE_GETREGS_OLD */
1138
1139 #endif /* ARCH_REGS_FOR_GETREGSET || ARCH_REGS_FOR_GETREGS */
1140
1141 void
1142 get_regs(pid_t pid)
1143 {
1144 #undef USE_GET_SYSCALL_RESULT_REGS
1145 #ifdef ptrace_getregset_or_getregs
1146
1147 # ifdef HAVE_GETREGS_OLD
1148         /*
1149          * Try PTRACE_GETREGSET/PTRACE_GETREGS first,
1150          * fallback to getregs_old.
1151          */
1152         static int use_getregs_old;
1153         if (use_getregs_old < 0) {
1154                 get_regs_error = ptrace_getregset_or_getregs(pid);
1155                 return;
1156         } else if (use_getregs_old == 0) {
1157                 get_regs_error = ptrace_getregset_or_getregs(pid);
1158                 if (get_regs_error >= 0) {
1159                         use_getregs_old = -1;
1160                         return;
1161                 }
1162                 if (errno == EPERM || errno == ESRCH)
1163                         return;
1164                 use_getregs_old = 1;
1165         }
1166         get_regs_error = getregs_old(pid);
1167 # else /* !HAVE_GETREGS_OLD */
1168         /* Assume that PTRACE_GETREGSET/PTRACE_GETREGS works. */
1169         get_regs_error = ptrace_getregset_or_getregs(pid);
1170 # endif /* !HAVE_GETREGS_OLD */
1171
1172 #else /* !ptrace_getregset_or_getregs */
1173
1174 # define USE_GET_SYSCALL_RESULT_REGS 1
1175 # warning get_regs is not implemented for this architecture yet
1176         get_regs_error = 0;
1177
1178 #endif /* !ptrace_getregset_or_getregs */
1179 }
1180
1181 #ifdef ptrace_setregset_or_setregs
1182 static int
1183 set_regs(pid_t pid)
1184 {
1185         return ptrace_setregset_or_setregs(pid);
1186 }
1187 #endif /* ptrace_setregset_or_setregs */
1188
1189 struct sysent_buf {
1190         struct tcb *tcp;
1191         struct_sysent ent;
1192         char buf[sizeof("syscall_%lu") + sizeof(long) * 3];
1193 };
1194
1195 static void
1196 free_sysent_buf(void *ptr)
1197 {
1198         struct sysent_buf *s = ptr;
1199         s->tcp->s_prev_ent = s->tcp->s_ent = NULL;
1200         free(ptr);
1201 }
1202
1203 /*
1204  * Returns:
1205  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1206  * 1: ok, continue in trace_syscall_entering().
1207  * other: error, trace_syscall_entering() should print error indicator
1208  *    ("????" etc) and bail out.
1209  */
1210 int
1211 get_scno(struct tcb *tcp)
1212 {
1213         if (get_regs_error)
1214                 return -1;
1215
1216         int rc = arch_get_scno(tcp);
1217         if (rc != 1)
1218                 return rc;
1219
1220         if (scno_is_valid(tcp->scno)) {
1221                 tcp->s_ent = &sysent[tcp->scno];
1222                 tcp->qual_flg = qual_flags(tcp->scno);
1223         } else {
1224                 struct sysent_buf *s = xcalloc(1, sizeof(*s));
1225
1226                 s->tcp = tcp;
1227                 s->ent.nargs = MAX_ARGS;
1228                 s->ent.sen = SEN_printargs;
1229                 s->ent.sys_func = printargs;
1230                 s->ent.sys_name = s->buf;
1231                 sprintf(s->buf, "syscall_%lu", shuffle_scno(tcp->scno));
1232
1233                 tcp->s_ent = &s->ent;
1234                 tcp->qual_flg = QUAL_RAW | DEFAULT_QUAL_FLAGS;
1235
1236                 set_tcb_priv_data(tcp, s, free_sysent_buf);
1237
1238                 if (debug_flag)
1239                         error_msg("pid %d invalid syscall %ld", tcp->pid, tcp->scno);
1240         }
1241         return 1;
1242 }
1243
1244 #ifdef USE_GET_SYSCALL_RESULT_REGS
1245 static int get_syscall_result_regs(struct tcb *);
1246 #endif
1247
1248 /* Returns:
1249  * 1: ok, continue in trace_syscall_exiting().
1250  * -1: error, trace_syscall_exiting() should print error indicator
1251  *    ("????" etc) and bail out.
1252  */
1253 static int
1254 get_syscall_result(struct tcb *tcp)
1255 {
1256 #ifdef USE_GET_SYSCALL_RESULT_REGS
1257         if (get_syscall_result_regs(tcp))
1258                 return -1;
1259 #endif
1260         tcp->u_error = 0;
1261         get_error(tcp, !(tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS));
1262
1263         return 1;
1264 }
1265
1266 #include "get_scno.c"
1267 #include "set_scno.c"
1268 #include "get_syscall_args.c"
1269 #ifdef USE_GET_SYSCALL_RESULT_REGS
1270 # include "get_syscall_result.c"
1271 #endif
1272 #include "get_error.c"
1273 #include "set_error.c"
1274 #ifdef HAVE_GETREGS_OLD
1275 # include "getregs_old.c"
1276 #endif
1277
1278 const char *
1279 syscall_name(kernel_scno_t scno)
1280 {
1281 #if defined X32_PERSONALITY_NUMBER && defined __X32_SYSCALL_BIT
1282         if (current_personality == X32_PERSONALITY_NUMBER)
1283                 scno &= ~__X32_SYSCALL_BIT;
1284 #endif
1285         return scno_is_valid(scno) ? sysent[scno].sys_name: NULL;
1286 }