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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 <sys/user.h>
36 #include <sys/param.h>
37
38 #ifdef HAVE_SYS_REG_H
39 # include <sys/reg.h>
40 #endif
41
42 #ifdef HAVE_LINUX_PTRACE_H
43 # undef PTRACE_SYSCALL
44 # ifdef HAVE_STRUCT_IA64_FPREG
45 #  define ia64_fpreg XXX_ia64_fpreg
46 # endif
47 # ifdef HAVE_STRUCT_PT_ALL_USER_REGS
48 #  define pt_all_user_regs XXX_pt_all_user_regs
49 # endif
50 # ifdef HAVE_STRUCT_PTRACE_PEEKSIGINFO_ARGS
51 #  define ptrace_peeksiginfo_args XXX_ptrace_peeksiginfo_args
52 # endif
53 # include <linux/ptrace.h>
54 # undef ptrace_peeksiginfo_args
55 # undef ia64_fpreg
56 # undef pt_all_user_regs
57 #endif
58
59 #if defined(SPARC64)
60 # undef PTRACE_GETREGS
61 # define PTRACE_GETREGS PTRACE_GETREGS64
62 # undef PTRACE_SETREGS
63 # define PTRACE_SETREGS PTRACE_SETREGS64
64 #endif
65
66 #if defined(IA64)
67 # include <asm/ptrace_offsets.h>
68 # include <asm/rse.h>
69 #endif
70
71 /* for struct iovec */
72 #include <sys/uio.h>
73 /* for NT_PRSTATUS */
74 #ifdef HAVE_ELF_H
75 # include <elf.h>
76 #endif
77
78 #if defined(AARCH64)
79 # include <asm/ptrace.h>
80 #endif
81
82 #if defined(XTENSA)
83 # include <asm/ptrace.h>
84 #endif
85
86 #ifndef NSIG
87 # warning: NSIG is not defined, using 32
88 # define NSIG 32
89 #endif
90
91 #include "syscall.h"
92
93 /* Define these shorthand notations to simplify the syscallent files. */
94 #define TD TRACE_DESC
95 #define TF TRACE_FILE
96 #define TI TRACE_IPC
97 #define TN TRACE_NETWORK
98 #define TP TRACE_PROCESS
99 #define TS TRACE_SIGNAL
100 #define TM TRACE_MEMORY
101 #define NF SYSCALL_NEVER_FAILS
102 #define MA MAX_ARGS
103 #define SI STACKTRACE_INVALIDATE_CACHE
104 #define SE STACKTRACE_CAPTURE_ON_ENTER
105
106 const struct_sysent sysent0[] = {
107 #include "syscallent.h"
108 };
109
110 #if SUPPORTED_PERSONALITIES > 1
111 static const struct_sysent sysent1[] = {
112 # include "syscallent1.h"
113 };
114 #endif
115
116 #if SUPPORTED_PERSONALITIES > 2
117 static const struct_sysent sysent2[] = {
118 # include "syscallent2.h"
119 };
120 #endif
121
122 /* Now undef them since short defines cause wicked namespace pollution. */
123 #undef TD
124 #undef TF
125 #undef TI
126 #undef TN
127 #undef TP
128 #undef TS
129 #undef TM
130 #undef NF
131 #undef MA
132 #undef SI
133 #undef SE
134
135 /*
136  * `ioctlent[012].h' files are automatically generated by the auxiliary
137  * program `ioctlsort', such that the list is sorted by the `code' field.
138  * This has the side-effect of resolving the _IO.. macros into
139  * plain integers, eliminating the need to include here everything
140  * in "/usr/include".
141  */
142
143 const char *const errnoent0[] = {
144 #include "errnoent.h"
145 };
146 const char *const signalent0[] = {
147 #include "signalent.h"
148 };
149 const struct_ioctlent ioctlent0[] = {
150 #include "ioctlent0.h"
151 };
152
153 #if SUPPORTED_PERSONALITIES > 1
154 static const char *const errnoent1[] = {
155 # include "errnoent1.h"
156 };
157 static const char *const signalent1[] = {
158 # include "signalent1.h"
159 };
160 static const struct_ioctlent ioctlent1[] = {
161 # include "ioctlent1.h"
162 };
163 #endif
164
165 #if SUPPORTED_PERSONALITIES > 2
166 static const char *const errnoent2[] = {
167 # include "errnoent2.h"
168 };
169 static const char *const signalent2[] = {
170 # include "signalent2.h"
171 };
172 static const struct_ioctlent ioctlent2[] = {
173 # include "ioctlent2.h"
174 };
175 #endif
176
177 enum {
178         nsyscalls0 = ARRAY_SIZE(sysent0)
179 #if SUPPORTED_PERSONALITIES > 1
180         , nsyscalls1 = ARRAY_SIZE(sysent1)
181 # if SUPPORTED_PERSONALITIES > 2
182         , nsyscalls2 = ARRAY_SIZE(sysent2)
183 # endif
184 #endif
185 };
186
187 enum {
188         nerrnos0 = ARRAY_SIZE(errnoent0)
189 #if SUPPORTED_PERSONALITIES > 1
190         , nerrnos1 = ARRAY_SIZE(errnoent1)
191 # if SUPPORTED_PERSONALITIES > 2
192         , nerrnos2 = ARRAY_SIZE(errnoent2)
193 # endif
194 #endif
195 };
196
197 enum {
198         nsignals0 = ARRAY_SIZE(signalent0)
199 #if SUPPORTED_PERSONALITIES > 1
200         , nsignals1 = ARRAY_SIZE(signalent1)
201 # if SUPPORTED_PERSONALITIES > 2
202         , nsignals2 = ARRAY_SIZE(signalent2)
203 # endif
204 #endif
205 };
206
207 enum {
208         nioctlents0 = ARRAY_SIZE(ioctlent0)
209 #if SUPPORTED_PERSONALITIES > 1
210         , nioctlents1 = ARRAY_SIZE(ioctlent1)
211 # if SUPPORTED_PERSONALITIES > 2
212         , nioctlents2 = ARRAY_SIZE(ioctlent2)
213 # endif
214 #endif
215 };
216
217 #if SUPPORTED_PERSONALITIES > 1
218 const struct_sysent *sysent = sysent0;
219 const char *const *errnoent = errnoent0;
220 const char *const *signalent = signalent0;
221 const struct_ioctlent *ioctlent = ioctlent0;
222 #endif
223 unsigned nsyscalls = nsyscalls0;
224 unsigned nerrnos = nerrnos0;
225 unsigned nsignals = nsignals0;
226 unsigned nioctlents = nioctlents0;
227
228 unsigned num_quals;
229 qualbits_t *qual_vec[SUPPORTED_PERSONALITIES];
230
231 static const unsigned nsyscall_vec[SUPPORTED_PERSONALITIES] = {
232         nsyscalls0,
233 #if SUPPORTED_PERSONALITIES > 1
234         nsyscalls1,
235 #endif
236 #if SUPPORTED_PERSONALITIES > 2
237         nsyscalls2,
238 #endif
239 };
240 static const struct_sysent *const sysent_vec[SUPPORTED_PERSONALITIES] = {
241         sysent0,
242 #if SUPPORTED_PERSONALITIES > 1
243         sysent1,
244 #endif
245 #if SUPPORTED_PERSONALITIES > 2
246         sysent2,
247 #endif
248 };
249
250 enum {
251         MAX_NSYSCALLS1 = (nsyscalls0
252 #if SUPPORTED_PERSONALITIES > 1
253                         > nsyscalls1 ? nsyscalls0 : nsyscalls1
254 #endif
255                         ),
256         MAX_NSYSCALLS2 = (MAX_NSYSCALLS1
257 #if SUPPORTED_PERSONALITIES > 2
258                         > nsyscalls2 ? MAX_NSYSCALLS1 : nsyscalls2
259 #endif
260                         ),
261         MAX_NSYSCALLS = MAX_NSYSCALLS2,
262         /* We are ready for arches with up to 255 signals,
263          * even though the largest known signo is on MIPS and it is 128.
264          * The number of existing syscalls on all arches is
265          * larger that 255 anyway, so it is just a pedantic matter.
266          */
267         MIN_QUALS = MAX_NSYSCALLS > 255 ? MAX_NSYSCALLS : 255
268 };
269
270 #if SUPPORTED_PERSONALITIES > 1
271 unsigned current_personality;
272
273 # ifndef current_wordsize
274 unsigned current_wordsize;
275 static const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
276         PERSONALITY0_WORDSIZE,
277         PERSONALITY1_WORDSIZE,
278 # if SUPPORTED_PERSONALITIES > 2
279         PERSONALITY2_WORDSIZE,
280 # endif
281 };
282 # endif
283
284 void
285 set_personality(int personality)
286 {
287         nsyscalls = nsyscall_vec[personality];
288         sysent = sysent_vec[personality];
289
290         switch (personality) {
291         case 0:
292                 errnoent = errnoent0;
293                 nerrnos = nerrnos0;
294                 ioctlent = ioctlent0;
295                 nioctlents = nioctlents0;
296                 signalent = signalent0;
297                 nsignals = nsignals0;
298                 break;
299
300         case 1:
301                 errnoent = errnoent1;
302                 nerrnos = nerrnos1;
303                 ioctlent = ioctlent1;
304                 nioctlents = nioctlents1;
305                 signalent = signalent1;
306                 nsignals = nsignals1;
307                 break;
308
309 # if SUPPORTED_PERSONALITIES > 2
310         case 2:
311                 errnoent = errnoent2;
312                 nerrnos = nerrnos2;
313                 ioctlent = ioctlent2;
314                 nioctlents = nioctlents2;
315                 signalent = signalent2;
316                 nsignals = nsignals2;
317                 break;
318 # endif
319         }
320
321         current_personality = personality;
322 # ifndef current_wordsize
323         current_wordsize = personality_wordsize[personality];
324 # endif
325 }
326
327 static void
328 update_personality(struct tcb *tcp, unsigned int personality)
329 {
330         if (personality == current_personality)
331                 return;
332         set_personality(personality);
333
334         if (personality == tcp->currpers)
335                 return;
336         tcp->currpers = personality;
337
338 # if defined(POWERPC64)
339         if (!qflag) {
340                 static const char *const names[] = {"64 bit", "32 bit"};
341                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
342                         tcp->pid, names[personality]);
343         }
344 # elif defined(X86_64)
345         if (!qflag) {
346                 static const char *const names[] = {"64 bit", "32 bit", "x32"};
347                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
348                         tcp->pid, names[personality]);
349         }
350 # elif defined(X32)
351         if (!qflag) {
352                 static const char *const names[] = {"x32", "32 bit"};
353                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
354                         tcp->pid, names[personality]);
355         }
356 # elif defined(AARCH64)
357         if (!qflag) {
358                 static const char *const names[] = {"32-bit", "AArch64"};
359                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
360                         tcp->pid, names[personality]);
361         }
362 # elif defined(TILE)
363         if (!qflag) {
364                 static const char *const names[] = {"64-bit", "32-bit"};
365                 fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
366                         tcp->pid, names[personality]);
367         }
368 # endif
369 }
370 #endif
371
372 static int qual_syscall(), qual_signal(), qual_desc();
373
374 static const struct qual_options {
375         unsigned int bitflag;
376         const char *option_name;
377         int (*qualify)(const char *, int, int);
378         const char *argument_name;
379 } qual_options[] = {
380         { QUAL_TRACE,   "trace",        qual_syscall,   "system call"   },
381         { QUAL_TRACE,   "t",            qual_syscall,   "system call"   },
382         { QUAL_ABBREV,  "abbrev",       qual_syscall,   "system call"   },
383         { QUAL_ABBREV,  "a",            qual_syscall,   "system call"   },
384         { QUAL_VERBOSE, "verbose",      qual_syscall,   "system call"   },
385         { QUAL_VERBOSE, "v",            qual_syscall,   "system call"   },
386         { QUAL_RAW,     "raw",          qual_syscall,   "system call"   },
387         { QUAL_RAW,     "x",            qual_syscall,   "system call"   },
388         { QUAL_SIGNAL,  "signal",       qual_signal,    "signal"        },
389         { QUAL_SIGNAL,  "signals",      qual_signal,    "signal"        },
390         { QUAL_SIGNAL,  "s",            qual_signal,    "signal"        },
391         { QUAL_READ,    "read",         qual_desc,      "descriptor"    },
392         { QUAL_READ,    "reads",        qual_desc,      "descriptor"    },
393         { QUAL_READ,    "r",            qual_desc,      "descriptor"    },
394         { QUAL_WRITE,   "write",        qual_desc,      "descriptor"    },
395         { QUAL_WRITE,   "writes",       qual_desc,      "descriptor"    },
396         { QUAL_WRITE,   "w",            qual_desc,      "descriptor"    },
397         { 0,            NULL,           NULL,           NULL            },
398 };
399
400 static void
401 reallocate_qual(const unsigned int n)
402 {
403         unsigned p;
404         qualbits_t *qp;
405         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
406                 qp = qual_vec[p] = realloc(qual_vec[p], n * sizeof(qualbits_t));
407                 if (!qp)
408                         die_out_of_memory();
409                 memset(&qp[num_quals], 0, (n - num_quals) * sizeof(qualbits_t));
410         }
411         num_quals = n;
412 }
413
414 static void
415 qualify_one(const unsigned int n, unsigned int bitflag, const int not, const int pers)
416 {
417         int p;
418
419         if (num_quals <= n)
420                 reallocate_qual(n + 1);
421
422         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
423                 if (pers == p || pers < 0) {
424                         if (not)
425                                 qual_vec[p][n] &= ~bitflag;
426                         else
427                                 qual_vec[p][n] |= bitflag;
428                 }
429         }
430 }
431
432 static int
433 qual_syscall(const char *s, const unsigned int bitflag, const int not)
434 {
435         int p;
436         unsigned int i;
437         int rc = -1;
438
439         if (*s >= '0' && *s <= '9') {
440                 i = string_to_uint(s);
441                 if (i >= MAX_NSYSCALLS)
442                         return -1;
443                 qualify_one(i, bitflag, not, -1);
444                 return 0;
445         }
446
447         for (p = 0; p < SUPPORTED_PERSONALITIES; p++) {
448                 for (i = 0; i < nsyscall_vec[p]; i++) {
449                         if (sysent_vec[p][i].sys_name
450                          && strcmp(s, sysent_vec[p][i].sys_name) == 0
451                         ) {
452                                 qualify_one(i, bitflag, not, p);
453                                 rc = 0;
454                         }
455                 }
456         }
457
458         return rc;
459 }
460
461 static int
462 qual_signal(const char *s, const unsigned int bitflag, const int not)
463 {
464         unsigned int i;
465
466         if (*s >= '0' && *s <= '9') {
467                 int signo = string_to_uint(s);
468                 if (signo < 0 || signo > 255)
469                         return -1;
470                 qualify_one(signo, bitflag, not, -1);
471                 return 0;
472         }
473         if (strncasecmp(s, "SIG", 3) == 0)
474                 s += 3;
475         for (i = 0; i <= NSIG; i++) {
476                 if (strcasecmp(s, signame(i) + 3) == 0) {
477                         qualify_one(i, bitflag, not, -1);
478                         return 0;
479                 }
480         }
481         return -1;
482 }
483
484 static int
485 qual_desc(const char *s, const unsigned int bitflag, const int not)
486 {
487         if (*s >= '0' && *s <= '9') {
488                 int desc = string_to_uint(s);
489                 if (desc < 0 || desc > 0x7fff) /* paranoia */
490                         return -1;
491                 qualify_one(desc, bitflag, not, -1);
492                 return 0;
493         }
494         return -1;
495 }
496
497 static int
498 lookup_class(const char *s)
499 {
500         if (strcmp(s, "file") == 0)
501                 return TRACE_FILE;
502         if (strcmp(s, "ipc") == 0)
503                 return TRACE_IPC;
504         if (strcmp(s, "network") == 0)
505                 return TRACE_NETWORK;
506         if (strcmp(s, "process") == 0)
507                 return TRACE_PROCESS;
508         if (strcmp(s, "signal") == 0)
509                 return TRACE_SIGNAL;
510         if (strcmp(s, "desc") == 0)
511                 return TRACE_DESC;
512         if (strcmp(s, "memory") == 0)
513                 return TRACE_MEMORY;
514         return -1;
515 }
516
517 void
518 qualify(const char *s)
519 {
520         const struct qual_options *opt;
521         char *copy;
522         const char *p;
523         int not;
524         unsigned int i;
525
526         if (num_quals == 0)
527                 reallocate_qual(MIN_QUALS);
528
529         opt = &qual_options[0];
530         for (i = 0; (p = qual_options[i].option_name); i++) {
531                 unsigned int len = strlen(p);
532                 if (strncmp(s, p, len) == 0 && s[len] == '=') {
533                         opt = &qual_options[i];
534                         s += len + 1;
535                         break;
536                 }
537         }
538         not = 0;
539         if (*s == '!') {
540                 not = 1;
541                 s++;
542         }
543         if (strcmp(s, "none") == 0) {
544                 not = 1 - not;
545                 s = "all";
546         }
547         if (strcmp(s, "all") == 0) {
548                 for (i = 0; i < num_quals; i++) {
549                         qualify_one(i, opt->bitflag, not, -1);
550                 }
551                 return;
552         }
553         for (i = 0; i < num_quals; i++) {
554                 qualify_one(i, opt->bitflag, !not, -1);
555         }
556         copy = strdup(s);
557         if (!copy)
558                 die_out_of_memory();
559         for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
560                 int n;
561                 if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
562                         unsigned pers;
563                         for (pers = 0; pers < SUPPORTED_PERSONALITIES; pers++) {
564                                 for (i = 0; i < nsyscall_vec[pers]; i++)
565                                         if (sysent_vec[pers][i].sys_flags & n)
566                                                 qualify_one(i, opt->bitflag, not, pers);
567                         }
568                         continue;
569                 }
570                 if (opt->qualify(p, opt->bitflag, not)) {
571                         error_msg_and_die("invalid %s '%s'",
572                                 opt->argument_name, p);
573                 }
574         }
575         free(copy);
576         return;
577 }
578
579 #ifdef SYS_socket_subcall
580 static void
581 decode_socket_subcall(struct tcb *tcp)
582 {
583         unsigned long addr;
584         unsigned int i, n, size;
585
586         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_socket_nsubcalls)
587                 return;
588
589         tcp->scno = SYS_socket_subcall + tcp->u_arg[0];
590         tcp->qual_flg = qual_flags[tcp->scno];
591         tcp->s_ent = &sysent[tcp->scno];
592         addr = tcp->u_arg[1];
593         size = current_wordsize;
594         n = tcp->s_ent->nargs;
595         for (i = 0; i < n; ++i) {
596                 if (size == sizeof(int)) {
597                         unsigned int arg;
598                         if (umove(tcp, addr, &arg) < 0)
599                                 arg = 0;
600                         tcp->u_arg[i] = arg;
601                 }
602                 else {
603                         unsigned long arg;
604                         if (umove(tcp, addr, &arg) < 0)
605                                 arg = 0;
606                         tcp->u_arg[i] = arg;
607                 }
608                 addr += size;
609         }
610 }
611 #endif
612
613 #ifdef SYS_ipc_subcall
614 static void
615 decode_ipc_subcall(struct tcb *tcp)
616 {
617         unsigned int i, n;
618
619         if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= SYS_ipc_nsubcalls)
620                 return;
621
622         tcp->scno = SYS_ipc_subcall + tcp->u_arg[0];
623         tcp->qual_flg = qual_flags[tcp->scno];
624         tcp->s_ent = &sysent[tcp->scno];
625         n = tcp->s_ent->nargs;
626         for (i = 0; i < n; i++)
627                 tcp->u_arg[i] = tcp->u_arg[i + 1];
628 }
629 #endif
630
631 int
632 printargs(struct tcb *tcp)
633 {
634         if (entering(tcp)) {
635                 int i;
636                 int n = tcp->s_ent->nargs;
637                 for (i = 0; i < n; i++)
638                         tprintf("%s%#lx", i ? ", " : "", tcp->u_arg[i]);
639         }
640         return 0;
641 }
642
643 int
644 printargs_lu(struct tcb *tcp)
645 {
646         if (entering(tcp)) {
647                 int i;
648                 int n = tcp->s_ent->nargs;
649                 for (i = 0; i < n; i++)
650                         tprintf("%s%lu", i ? ", " : "", tcp->u_arg[i]);
651         }
652         return 0;
653 }
654
655 int
656 printargs_ld(struct tcb *tcp)
657 {
658         if (entering(tcp)) {
659                 int i;
660                 int n = tcp->s_ent->nargs;
661                 for (i = 0; i < n; i++)
662                         tprintf("%s%ld", i ? ", " : "", tcp->u_arg[i]);
663         }
664         return 0;
665 }
666
667 #if defined(SPARC) || defined(SPARC64) || defined(IA64) || defined(SH)
668 long
669 getrval2(struct tcb *tcp)
670 {
671         long val;
672
673 # if defined(SPARC) || defined(SPARC64)
674         val = sparc_regs.u_regs[U_REG_O1];
675 # elif defined(SH)
676         if (upeek(tcp->pid, 4*(REG_REG0+1), &val) < 0)
677                 return -1;
678 # elif defined(IA64)
679         if (upeek(tcp->pid, PT_R9, &val) < 0)
680                 return -1;
681 # endif
682
683         return val;
684 }
685 #endif
686
687 #if defined(I386)
688 static struct user_regs_struct i386_regs;
689 /* Cast suppresses signedness warning (.esp is long, not unsigned long) */
690 uint32_t *const i386_esp_ptr = (uint32_t*)&i386_regs.esp;
691 # define ARCH_REGS_FOR_GETREGSET i386_regs
692 #elif defined(X86_64) || defined(X32)
693 /*
694  * On i386, pt_regs and user_regs_struct are the same,
695  * but on 64 bit x86, user_regs_struct has six more fields:
696  * fs_base, gs_base, ds, es, fs, gs.
697  * PTRACE_GETREGS fills them too, so struct pt_regs would overflow.
698  */
699 struct i386_user_regs_struct {
700         uint32_t ebx;
701         uint32_t ecx;
702         uint32_t edx;
703         uint32_t esi;
704         uint32_t edi;
705         uint32_t ebp;
706         uint32_t eax;
707         uint32_t xds;
708         uint32_t xes;
709         uint32_t xfs;
710         uint32_t xgs;
711         uint32_t orig_eax;
712         uint32_t eip;
713         uint32_t xcs;
714         uint32_t eflags;
715         uint32_t esp;
716         uint32_t xss;
717 };
718 static union {
719         struct user_regs_struct      x86_64_r;
720         struct i386_user_regs_struct i386_r;
721 } x86_regs_union;
722 # define x86_64_regs x86_regs_union.x86_64_r
723 # define i386_regs   x86_regs_union.i386_r
724 uint32_t *const i386_esp_ptr = &i386_regs.esp;
725 static struct iovec x86_io = {
726         .iov_base = &x86_regs_union
727 };
728 #elif defined(IA64)
729 bool ia64_ia32mode = 0; /* not static */
730 static long ia64_r8, ia64_r10;
731 #elif defined(POWERPC)
732 struct pt_regs ppc_regs;
733 #elif defined(M68K)
734 static long m68k_d0;
735 #elif defined(BFIN)
736 static long bfin_r0;
737 #elif defined(ARM)
738 struct pt_regs arm_regs; /* not static */
739 # define ARCH_REGS_FOR_GETREGSET arm_regs
740 #elif defined(AARCH64)
741 static union {
742         struct user_pt_regs aarch64_r;
743         struct arm_pt_regs  arm_r;
744 } arm_regs_union;
745 # define aarch64_regs arm_regs_union.aarch64_r
746 # define arm_regs     arm_regs_union.arm_r
747 static struct iovec aarch64_io = {
748         .iov_base = &arm_regs_union
749 };
750 #elif defined(ALPHA)
751 static long alpha_r0;
752 static long alpha_a3;
753 #elif defined(AVR32)
754 static struct pt_regs avr32_regs;
755 #elif defined(SPARC) || defined(SPARC64)
756 struct pt_regs sparc_regs; /* not static */
757 #elif defined(LINUX_MIPSN32)
758 static long long mips_a3;
759 static long long mips_r2;
760 #elif defined(MIPS)
761 static long mips_a3;
762 static long mips_r2;
763 #elif defined(S390) || defined(S390X)
764 static long s390_gpr2;
765 #elif defined(HPPA)
766 static long hppa_r28;
767 #elif defined(SH)
768 static long sh_r0;
769 #elif defined(SH64)
770 static long sh64_r9;
771 #elif defined(CRISV10) || defined(CRISV32)
772 static long cris_r10;
773 #elif defined(TILE)
774 struct pt_regs tile_regs;
775 #elif defined(MICROBLAZE)
776 static long microblaze_r3;
777 #elif defined(OR1K)
778 static struct user_regs_struct or1k_regs;
779 # define ARCH_REGS_FOR_GETREGSET or1k_regs
780 #elif defined(METAG)
781 static struct user_gp_regs metag_regs;
782 # define ARCH_REGS_FOR_GETREGSET metag_regs
783 #elif defined(XTENSA)
784 static long xtensa_a2;
785 # elif defined(ARC)
786 static struct user_regs_struct arc_regs;
787 # define ARCH_REGS_FOR_GETREGSET arc_regs
788 #endif
789
790 void
791 print_pc(struct tcb *tcp)
792 {
793 #define PRINTBADPC tprintf(sizeof(long) == 4 ? "[????????] " : \
794                            sizeof(long) == 8 ? "[????????????????] " : \
795                            NULL /* crash */)
796         if (get_regs_error) {
797                 PRINTBADPC;
798                 return;
799         }
800 #if defined(I386)
801         tprintf("[%08lx] ", i386_regs.eip);
802 #elif defined(S390) || defined(S390X)
803         long psw;
804         if (upeek(tcp->pid, PT_PSWADDR, &psw) < 0) {
805                 PRINTBADPC;
806                 return;
807         }
808 # ifdef S390
809         tprintf("[%08lx] ", psw);
810 # elif S390X
811         tprintf("[%016lx] ", psw);
812 # endif
813 #elif defined(X86_64) || defined(X32)
814         if (x86_io.iov_len == sizeof(i386_regs)) {
815                 tprintf("[%08x] ", (unsigned) i386_regs.eip);
816         } else {
817 # if defined(X86_64)
818                 tprintf("[%016lx] ", (unsigned long) x86_64_regs.rip);
819 # elif defined(X32)
820                 /* Note: this truncates 64-bit rip to 32 bits */
821                 tprintf("[%08lx] ", (unsigned long) x86_64_regs.rip);
822 # endif
823         }
824 #elif defined(IA64)
825         long ip;
826         if (upeek(tcp->pid, PT_B0, &ip) < 0) {
827                 PRINTBADPC;
828                 return;
829         }
830         tprintf("[%08lx] ", ip);
831 #elif defined(POWERPC)
832         long pc = ppc_regs.nip;
833 # ifdef POWERPC64
834         tprintf("[%016lx] ", pc);
835 # else
836         tprintf("[%08lx] ", pc);
837 # endif
838 #elif defined(M68K)
839         long pc;
840         if (upeek(tcp->pid, 4*PT_PC, &pc) < 0) {
841                 tprints("[????????] ");
842                 return;
843         }
844         tprintf("[%08lx] ", pc);
845 #elif defined(ALPHA)
846         long pc;
847         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
848                 tprints("[????????????????] ");
849                 return;
850         }
851         tprintf("[%08lx] ", pc);
852 #elif defined(SPARC)
853         tprintf("[%08lx] ", sparc_regs.pc);
854 #elif defined(SPARC64)
855         tprintf("[%08lx] ", sparc_regs.tpc);
856 #elif defined(HPPA)
857         long pc;
858         if (upeek(tcp->pid, PT_IAOQ0, &pc) < 0) {
859                 tprints("[????????] ");
860                 return;
861         }
862         tprintf("[%08lx] ", pc);
863 #elif defined(MIPS)
864         long pc;
865         if (upeek(tcp->pid, REG_EPC, &pc) < 0) {
866                 tprints("[????????] ");
867                 return;
868         }
869         tprintf("[%08lx] ", pc);
870 #elif defined(SH)
871         long pc;
872         if (upeek(tcp->pid, 4*REG_PC, &pc) < 0) {
873                 tprints("[????????] ");
874                 return;
875         }
876         tprintf("[%08lx] ", pc);
877 #elif defined(SH64)
878         long pc;
879         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
880                 tprints("[????????????????] ");
881                 return;
882         }
883         tprintf("[%08lx] ", pc);
884 #elif defined(ARM)
885         tprintf("[%08lx] ", arm_regs.ARM_pc);
886 #elif defined(AARCH64)
887         /* tprintf("[%016lx] ", aarch64_regs.regs[???]); */
888 #elif defined(AVR32)
889         tprintf("[%08lx] ", avr32_regs.pc);
890 #elif defined(BFIN)
891         long pc;
892         if (upeek(tcp->pid, PT_PC, &pc) < 0) {
893                 PRINTBADPC;
894                 return;
895         }
896         tprintf("[%08lx] ", pc);
897 #elif defined(CRISV10)
898         long pc;
899         if (upeek(tcp->pid, 4*PT_IRP, &pc) < 0) {
900                 PRINTBADPC;
901                 return;
902         }
903         tprintf("[%08lx] ", pc);
904 #elif defined(CRISV32)
905         long pc;
906         if (upeek(tcp->pid, 4*PT_ERP, &pc) < 0) {
907                 PRINTBADPC;
908                 return;
909         }
910         tprintf("[%08lx] ", pc);
911 #elif defined(TILE)
912 # ifdef _LP64
913         tprintf("[%016lx] ", (unsigned long) tile_regs.pc);
914 # else
915         tprintf("[%08lx] ", (unsigned long) tile_regs.pc);
916 # endif
917 #elif defined(OR1K)
918         tprintf("[%08lx] ", or1k_regs.pc);
919 #elif defined(METAG)
920         tprintf("[%08lx] ", metag_regs.pc);
921 #elif defined(XTENSA)
922         long pc;
923         if (upeek(tcp->pid, REG_PC, &pc) < 0) {
924                 PRINTBADPC;
925                 return;
926         }
927         tprintf("[%08lx] ", pc);
928 #elif defined(ARC)
929         tprintf("[%08lx] ", arc_regs.efa);
930 #endif /* architecture */
931 }
932
933 /*
934  * Shuffle syscall numbers so that we don't have huge gaps in syscall table.
935  * The shuffling should be an involution: shuffle_scno(shuffle_scno(n)) == n.
936  */
937 #if defined(ARM) || defined(AARCH64) /* So far only 32-bit ARM needs this */
938 static long
939 shuffle_scno(unsigned long scno)
940 {
941         if (scno < ARM_FIRST_SHUFFLED_SYSCALL)
942                 return scno;
943
944         /* __ARM_NR_cmpxchg? Swap with LAST_ORDINARY+1 */
945         if (scno == ARM_FIRST_SHUFFLED_SYSCALL)
946                 return 0x000ffff0;
947         if (scno == 0x000ffff0)
948                 return ARM_FIRST_SHUFFLED_SYSCALL;
949
950 #define ARM_SECOND_SHUFFLED_SYSCALL (ARM_FIRST_SHUFFLED_SYSCALL + 1)
951         /*
952          * Is it ARM specific syscall?
953          * Swap [0x000f0000, 0x000f0000 + LAST_SPECIAL] range
954          * with [SECOND_SHUFFLED, SECOND_SHUFFLED + LAST_SPECIAL] range.
955          */
956         if (scno >= 0x000f0000 &&
957             scno <= 0x000f0000 + ARM_LAST_SPECIAL_SYSCALL) {
958                 return scno - 0x000f0000 + ARM_SECOND_SHUFFLED_SYSCALL;
959         }
960         if (scno <= ARM_SECOND_SHUFFLED_SYSCALL + ARM_LAST_SPECIAL_SYSCALL) {
961                 return scno + 0x000f0000 - ARM_SECOND_SHUFFLED_SYSCALL;
962         }
963
964         return scno;
965 }
966 #else
967 # define shuffle_scno(scno) ((long)(scno))
968 #endif
969
970 static char*
971 undefined_scno_name(struct tcb *tcp)
972 {
973         static char buf[sizeof("syscall_%lu") + sizeof(long)*3];
974
975         sprintf(buf, "syscall_%lu", shuffle_scno(tcp->scno));
976         return buf;
977 }
978
979 #ifdef POWERPC
980 /*
981  * PTRACE_GETREGS was added to the PowerPC kernel in v2.6.23,
982  * we provide a slow fallback for old kernels.
983  */
984 static int powerpc_getregs_old(pid_t pid)
985 {
986         int i;
987         long r;
988
989         if (iflag) {
990                 r = upeek(pid, sizeof(long) * PT_NIP, (long *)&ppc_regs.nip);
991                 if (r)
992                         goto out;
993         }
994 #ifdef POWERPC64 /* else we never use it */
995         r = upeek(pid, sizeof(long) * PT_MSR, (long *)&ppc_regs.msr);
996         if (r)
997                 goto out;
998 #endif
999         r = upeek(pid, sizeof(long) * PT_CCR, (long *)&ppc_regs.ccr);
1000         if (r)
1001                 goto out;
1002         r = upeek(pid, sizeof(long) * PT_ORIG_R3, (long *)&ppc_regs.orig_gpr3);
1003         if (r)
1004                 goto out;
1005         for (i = 0; i <= 8; i++) {
1006                 r = upeek(pid, sizeof(long) * (PT_R0 + i),
1007                           (long *)&ppc_regs.gpr[i]);
1008                 if (r)
1009                         goto out;
1010         }
1011  out:
1012         return r;
1013 }
1014 #endif
1015
1016 #ifndef get_regs
1017 long get_regs_error;
1018
1019 #if defined(PTRACE_GETREGSET) && defined(NT_PRSTATUS)
1020 static void get_regset(pid_t pid)
1021 {
1022 /* constant iovec */
1023 # if defined(ARM) \
1024   || defined(I386) \
1025   || defined(METAG) \
1026   || defined(OR1K) \
1027   || defined(ARC)
1028         static struct iovec io = {
1029                 .iov_base = &ARCH_REGS_FOR_GETREGSET,
1030                 .iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
1031         };
1032         get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &io);
1033
1034 /* variable iovec */
1035 # elif defined(X86_64) || defined(X32)
1036         /* x86_io.iov_base = &x86_regs_union; - already is */
1037         x86_io.iov_len = sizeof(x86_regs_union);
1038         get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &x86_io);
1039 # elif defined(AARCH64)
1040         /* aarch64_io.iov_base = &arm_regs_union; - already is */
1041         aarch64_io.iov_len = sizeof(arm_regs_union);
1042         get_regs_error = ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, &aarch64_io);
1043 # else
1044 #  warning both PTRACE_GETREGSET and NT_PRSTATUS are available but not yet used
1045 # endif
1046 }
1047 #endif /* PTRACE_GETREGSET && NT_PRSTATUS */
1048
1049 void
1050 get_regs(pid_t pid)
1051 {
1052 /* PTRACE_GETREGSET only */
1053 # if defined(METAG) || defined(OR1K) || defined(X32) || defined(AARCH64) || defined(ARC)
1054         get_regset(pid);
1055
1056 /* PTRACE_GETREGS only */
1057 # elif defined(AVR32)
1058         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &avr32_regs);
1059 # elif defined(TILE)
1060         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &tile_regs);
1061 # elif defined(SPARC) || defined(SPARC64)
1062         get_regs_error = ptrace(PTRACE_GETREGS, pid, (char *)&sparc_regs, 0);
1063 # elif defined(POWERPC)
1064         static bool old_kernel = 0;
1065         if (old_kernel)
1066                 goto old;
1067         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, (long) &ppc_regs);
1068         if (get_regs_error && errno == EIO) {
1069                 old_kernel = 1;
1070  old:
1071                 get_regs_error = powerpc_getregs_old(pid);
1072         }
1073
1074 /* try PTRACE_GETREGSET first, fallback to PTRACE_GETREGS */
1075 # else
1076 #  if defined(PTRACE_GETREGSET) && defined(NT_PRSTATUS)
1077         static int getregset_support;
1078
1079         if (getregset_support >= 0) {
1080                 get_regset(pid);
1081                 if (getregset_support > 0)
1082                         return;
1083                 if (get_regs_error >= 0) {
1084                         getregset_support = 1;
1085                         return;
1086                 }
1087                 if (errno == EPERM || errno == ESRCH)
1088                         return;
1089                 getregset_support = -1;
1090         }
1091 #  endif /* PTRACE_GETREGSET && NT_PRSTATUS */
1092 #  if defined(ARM)
1093         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &arm_regs);
1094 #  elif defined(I386)
1095         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &i386_regs);
1096 #  elif defined(X86_64)
1097         /* Use old method, with unreliable heuristical detection of 32-bitness. */
1098         x86_io.iov_len = sizeof(x86_64_regs);
1099         get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &x86_64_regs);
1100         if (!get_regs_error && x86_64_regs.cs == 0x23) {
1101                 x86_io.iov_len = sizeof(i386_regs);
1102                 /*
1103                  * The order is important: i386_regs and x86_64_regs
1104                  * are overlaid in memory!
1105                  */
1106                 i386_regs.ebx = x86_64_regs.rbx;
1107                 i386_regs.ecx = x86_64_regs.rcx;
1108                 i386_regs.edx = x86_64_regs.rdx;
1109                 i386_regs.esi = x86_64_regs.rsi;
1110                 i386_regs.edi = x86_64_regs.rdi;
1111                 i386_regs.ebp = x86_64_regs.rbp;
1112                 i386_regs.eax = x86_64_regs.rax;
1113                 /* i386_regs.xds = x86_64_regs.ds; unused by strace */
1114                 /* i386_regs.xes = x86_64_regs.es; ditto... */
1115                 /* i386_regs.xfs = x86_64_regs.fs; */
1116                 /* i386_regs.xgs = x86_64_regs.gs; */
1117                 i386_regs.orig_eax = x86_64_regs.orig_rax;
1118                 i386_regs.eip = x86_64_regs.rip;
1119                 /* i386_regs.xcs = x86_64_regs.cs; */
1120                 /* i386_regs.eflags = x86_64_regs.eflags; */
1121                 i386_regs.esp = x86_64_regs.rsp;
1122                 /* i386_regs.xss = x86_64_regs.ss; */
1123         }
1124 #  else
1125 #   error unhandled architecture
1126 #  endif /* ARM || I386 || X86_64 */
1127 # endif
1128 }
1129 #endif /* !get_regs */
1130
1131 /* Returns:
1132  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1133  * 1: ok, continue in trace_syscall_entering().
1134  * other: error, trace_syscall_entering() should print error indicator
1135  *    ("????" etc) and bail out.
1136  */
1137 static int
1138 get_scno(struct tcb *tcp)
1139 {
1140         long scno = 0;
1141
1142 #if defined(S390) || defined(S390X)
1143         if (upeek(tcp->pid, PT_GPR2, &s390_gpr2) < 0)
1144                 return -1;
1145
1146         if (s390_gpr2 != -ENOSYS) {
1147                 /*
1148                  * Since kernel version 2.5.44 the scno gets passed in gpr2.
1149                  */
1150                 scno = s390_gpr2;
1151         } else {
1152                 /*
1153                  * Old style of "passing" the scno via the SVC instruction.
1154                  */
1155                 long psw;
1156                 long opcode, offset_reg, tmp;
1157                 void *svc_addr;
1158                 static const int gpr_offset[16] = {
1159                                 PT_GPR0,  PT_GPR1,  PT_ORIGGPR2, PT_GPR3,
1160                                 PT_GPR4,  PT_GPR5,  PT_GPR6,     PT_GPR7,
1161                                 PT_GPR8,  PT_GPR9,  PT_GPR10,    PT_GPR11,
1162                                 PT_GPR12, PT_GPR13, PT_GPR14,    PT_GPR15
1163                 };
1164
1165                 if (upeek(tcp->pid, PT_PSWADDR, &psw) < 0)
1166                         return -1;
1167                 errno = 0;
1168                 opcode = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)(psw - sizeof(long)), 0);
1169                 if (errno) {
1170                         perror_msg("peektext(psw-oneword)");
1171                         return -1;
1172                 }
1173
1174                 /*
1175                  *  We have to check if the SVC got executed directly or via an
1176                  *  EXECUTE instruction. In case of EXECUTE it is necessary to do
1177                  *  instruction decoding to derive the system call number.
1178                  *  Unfortunately the opcode sizes of EXECUTE and SVC are differently,
1179                  *  so that this doesn't work if a SVC opcode is part of an EXECUTE
1180                  *  opcode. Since there is no way to find out the opcode size this
1181                  *  is the best we can do...
1182                  */
1183                 if ((opcode & 0xff00) == 0x0a00) {
1184                         /* SVC opcode */
1185                         scno = opcode & 0xff;
1186                 }
1187                 else {
1188                         /* SVC got executed by EXECUTE instruction */
1189
1190                         /*
1191                          *  Do instruction decoding of EXECUTE. If you really want to
1192                          *  understand this, read the Principles of Operations.
1193                          */
1194                         svc_addr = (void *) (opcode & 0xfff);
1195
1196                         tmp = 0;
1197                         offset_reg = (opcode & 0x000f0000) >> 16;
1198                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1199                                 return -1;
1200                         svc_addr += tmp;
1201
1202                         tmp = 0;
1203                         offset_reg = (opcode & 0x0000f000) >> 12;
1204                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1205                                 return -1;
1206                         svc_addr += tmp;
1207
1208                         scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, svc_addr, 0);
1209                         if (errno)
1210                                 return -1;
1211 # if defined(S390X)
1212                         scno >>= 48;
1213 # else
1214                         scno >>= 16;
1215 # endif
1216                         tmp = 0;
1217                         offset_reg = (opcode & 0x00f00000) >> 20;
1218                         if (offset_reg && (upeek(tcp->pid, gpr_offset[offset_reg], &tmp) < 0))
1219                                 return -1;
1220
1221                         scno = (scno | tmp) & 0xff;
1222                 }
1223         }
1224 #elif defined(POWERPC)
1225         scno = ppc_regs.gpr[0];
1226 # ifdef POWERPC64
1227         unsigned int currpers;
1228
1229         /*
1230          * Check for 64/32 bit mode.
1231          * Embedded implementations covered by Book E extension of PPC use
1232          * bit 0 (CM) of 32-bit Machine state register (MSR).
1233          * Other implementations use bit 0 (SF) of 64-bit MSR.
1234          */
1235         currpers = (ppc_regs.msr & 0x8000000080000000) ? 0 : 1;
1236         update_personality(tcp, currpers);
1237 # endif
1238 #elif defined(AVR32)
1239         scno = avr32_regs.r8;
1240 #elif defined(BFIN)
1241         if (upeek(tcp->pid, PT_ORIG_P0, &scno))
1242                 return -1;
1243 #elif defined(I386)
1244         scno = i386_regs.orig_eax;
1245 #elif defined(X86_64) || defined(X32)
1246 # ifndef __X32_SYSCALL_BIT
1247 #  define __X32_SYSCALL_BIT     0x40000000
1248 # endif
1249         unsigned int currpers;
1250 # if 1
1251         /* GETREGSET of NT_PRSTATUS tells us regset size,
1252          * which unambiguously detects i386.
1253          *
1254          * Linux kernel distinguishes x86-64 and x32 processes
1255          * solely by looking at __X32_SYSCALL_BIT:
1256          * arch/x86/include/asm/compat.h::is_x32_task():
1257          * if (task_pt_regs(current)->orig_ax & __X32_SYSCALL_BIT)
1258          *         return true;
1259          */
1260         if (x86_io.iov_len == sizeof(i386_regs)) {
1261                 scno = i386_regs.orig_eax;
1262                 currpers = 1;
1263         } else {
1264                 scno = x86_64_regs.orig_rax;
1265                 currpers = 0;
1266                 if (scno & __X32_SYSCALL_BIT) {
1267                         /*
1268                          * Syscall number -1 requires special treatment:
1269                          * it might be a side effect of SECCOMP_RET_ERRNO
1270                          * filtering that sets orig_rax to -1
1271                          * in some versions of linux kernel.
1272                          * If that is the case, then
1273                          * __X32_SYSCALL_BIT logic does not apply.
1274                          */
1275                         if ((long long) x86_64_regs.orig_rax != -1) {
1276                                 scno -= __X32_SYSCALL_BIT;
1277                                 currpers = 2;
1278                         } else {
1279 #  ifdef X32
1280                                 currpers = 2;
1281 #  endif
1282                         }
1283                 }
1284         }
1285 # elif 0
1286         /* cs = 0x33 for long mode (native 64 bit and x32)
1287          * cs = 0x23 for compatibility mode (32 bit)
1288          * ds = 0x2b for x32 mode (x86-64 in 32 bit)
1289          */
1290         scno = x86_64_regs.orig_rax;
1291         switch (x86_64_regs.cs) {
1292                 case 0x23: currpers = 1; break;
1293                 case 0x33:
1294                         if (x86_64_regs.ds == 0x2b) {
1295                                 currpers = 2;
1296                                 scno &= ~__X32_SYSCALL_BIT;
1297                         } else
1298                                 currpers = 0;
1299                         break;
1300                 default:
1301                         fprintf(stderr, "Unknown value CS=0x%08X while "
1302                                  "detecting personality of process "
1303                                  "PID=%d\n", (int)x86_64_regs.cs, tcp->pid);
1304                         currpers = current_personality;
1305                         break;
1306         }
1307 # elif 0
1308         /* This version analyzes the opcode of a syscall instruction.
1309          * (int 0x80 on i386 vs. syscall on x86-64)
1310          * It works, but is too complicated, and strictly speaking, unreliable.
1311          */
1312         unsigned long call, rip = x86_64_regs.rip;
1313         /* sizeof(syscall) == sizeof(int 0x80) == 2 */
1314         rip -= 2;
1315         errno = 0;
1316         call = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)rip, (char *)0);
1317         if (errno)
1318                 fprintf(stderr, "ptrace_peektext failed: %s\n",
1319                                 strerror(errno));
1320         switch (call & 0xffff) {
1321                 /* x86-64: syscall = 0x0f 0x05 */
1322                 case 0x050f: currpers = 0; break;
1323                 /* i386: int 0x80 = 0xcd 0x80 */
1324                 case 0x80cd: currpers = 1; break;
1325                 default:
1326                         currpers = current_personality;
1327                         fprintf(stderr,
1328                                 "Unknown syscall opcode (0x%04X) while "
1329                                 "detecting personality of process "
1330                                 "PID=%d\n", (int)call, tcp->pid);
1331                         break;
1332         }
1333 # endif
1334
1335 # ifdef X32
1336         /* If we are built for a x32 system, then personality 0 is x32
1337          * (not x86_64), and stracing of x86_64 apps is not supported.
1338          * Stracing of i386 apps is still supported.
1339          */
1340         if (currpers == 0) {
1341                 fprintf(stderr, "syscall_%lu(...) in unsupported "
1342                                 "64-bit mode of process PID=%d\n",
1343                         scno, tcp->pid);
1344                 return 0;
1345         }
1346         currpers &= ~2; /* map 2,1 to 0,1 */
1347 # endif
1348         update_personality(tcp, currpers);
1349 #elif defined(IA64)
1350 #       define IA64_PSR_IS      ((long)1 << 34)
1351         long psr;
1352         if (upeek(tcp->pid, PT_CR_IPSR, &psr) >= 0)
1353                 ia64_ia32mode = ((psr & IA64_PSR_IS) != 0);
1354         if (ia64_ia32mode) {
1355                 if (upeek(tcp->pid, PT_R1, &scno) < 0)
1356                         return -1;
1357         } else {
1358                 if (upeek(tcp->pid, PT_R15, &scno) < 0)
1359                         return -1;
1360         }
1361 #elif defined(AARCH64)
1362         switch (aarch64_io.iov_len) {
1363                 case sizeof(aarch64_regs):
1364                         /* We are in 64-bit mode */
1365                         scno = aarch64_regs.regs[8];
1366                         update_personality(tcp, 1);
1367                         break;
1368                 case sizeof(arm_regs):
1369                         /* We are in 32-bit mode */
1370                         /* Note: we don't support OABI, unlike 32-bit ARM build */
1371                         scno = arm_regs.ARM_r7;
1372                         scno = shuffle_scno(scno);
1373                         update_personality(tcp, 0);
1374                         break;
1375         }
1376 #elif defined(ARM)
1377         if (arm_regs.ARM_ip != 0) {
1378                 /* It is not a syscall entry */
1379                 fprintf(stderr, "pid %d stray syscall exit\n", tcp->pid);
1380                 tcp->flags |= TCB_INSYSCALL;
1381                 return 0;
1382         }
1383         /* Note: we support only 32-bit CPUs, not 26-bit */
1384
1385 # if !defined(__ARM_EABI__) || ENABLE_ARM_OABI
1386         if (arm_regs.ARM_cpsr & 0x20)
1387                 /* Thumb mode */
1388                 goto scno_in_r7;
1389         /* ARM mode */
1390         /* Check EABI/OABI by examining SVC insn's low 24 bits */
1391         errno = 0;
1392         scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, (void *)(arm_regs.ARM_pc - 4), NULL);
1393         if (errno)
1394                 return -1;
1395         /* EABI syscall convention? */
1396         if ((unsigned long) scno != 0xef000000) {
1397                 /* No, it's OABI */
1398                 if ((scno & 0x0ff00000) != 0x0f900000) {
1399                         fprintf(stderr, "pid %d unknown syscall trap 0x%08lx\n",
1400                                 tcp->pid, scno);
1401                         return -1;
1402                 }
1403                 /* Fixup the syscall number */
1404                 scno &= 0x000fffff;
1405         } else {
1406  scno_in_r7:
1407                 scno = arm_regs.ARM_r7;
1408         }
1409 # else /* __ARM_EABI__ || !ENABLE_ARM_OABI */
1410         scno = arm_regs.ARM_r7;
1411 # endif
1412         scno = shuffle_scno(scno);
1413 #elif defined(M68K)
1414         if (upeek(tcp->pid, 4*PT_ORIG_D0, &scno) < 0)
1415                 return -1;
1416 #elif defined(LINUX_MIPSN32)
1417         unsigned long long regs[38];
1418
1419         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
1420                 return -1;
1421         mips_a3 = regs[REG_A3];
1422         mips_r2 = regs[REG_V0];
1423
1424         scno = mips_r2;
1425         if (!SCNO_IN_RANGE(scno)) {
1426                 if (mips_a3 == 0 || mips_a3 == -1) {
1427                         if (debug_flag)
1428                                 fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
1429                         return 0;
1430                 }
1431         }
1432 #elif defined(MIPS)
1433         if (upeek(tcp->pid, REG_A3, &mips_a3) < 0)
1434                 return -1;
1435         if (upeek(tcp->pid, REG_V0, &scno) < 0)
1436                 return -1;
1437
1438         if (!SCNO_IN_RANGE(scno)) {
1439                 if (mips_a3 == 0 || mips_a3 == -1) {
1440                         if (debug_flag)
1441                                 fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
1442                         return 0;
1443                 }
1444         }
1445 #elif defined(ALPHA)
1446         if (upeek(tcp->pid, REG_A3, &alpha_a3) < 0)
1447                 return -1;
1448         if (upeek(tcp->pid, REG_R0, &scno) < 0)
1449                 return -1;
1450
1451         /*
1452          * Do some sanity checks to figure out if it's
1453          * really a syscall entry
1454          */
1455         if (!SCNO_IN_RANGE(scno)) {
1456                 if (alpha_a3 == 0 || alpha_a3 == -1) {
1457                         if (debug_flag)
1458                                 fprintf(stderr, "stray syscall exit: r0 = %ld\n", scno);
1459                         return 0;
1460                 }
1461         }
1462 #elif defined(SPARC) || defined(SPARC64)
1463         /* Disassemble the syscall trap. */
1464         /* Retrieve the syscall trap instruction. */
1465         unsigned long trap;
1466         errno = 0;
1467 # if defined(SPARC64)
1468         trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)sparc_regs.tpc, 0);
1469         trap >>= 32;
1470 # else
1471         trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)sparc_regs.pc, 0);
1472 # endif
1473         if (errno)
1474                 return -1;
1475
1476         /* Disassemble the trap to see what personality to use. */
1477         switch (trap) {
1478         case 0x91d02010:
1479                 /* Linux/SPARC syscall trap. */
1480                 update_personality(tcp, 0);
1481                 break;
1482         case 0x91d0206d:
1483                 /* Linux/SPARC64 syscall trap. */
1484                 update_personality(tcp, 2);
1485                 break;
1486         case 0x91d02000:
1487                 /* SunOS syscall trap. (pers 1) */
1488                 fprintf(stderr, "syscall: SunOS no support\n");
1489                 return -1;
1490         case 0x91d02008:
1491                 /* Solaris 2.x syscall trap. (per 2) */
1492                 update_personality(tcp, 1);
1493                 break;
1494         case 0x91d02009:
1495                 /* NetBSD/FreeBSD syscall trap. */
1496                 fprintf(stderr, "syscall: NetBSD/FreeBSD not supported\n");
1497                 return -1;
1498         case 0x91d02027:
1499                 /* Solaris 2.x gettimeofday */
1500                 update_personality(tcp, 1);
1501                 break;
1502         default:
1503 # if defined(SPARC64)
1504                 fprintf(stderr, "syscall: unknown syscall trap %08lx %016lx\n", trap, sparc_regs.tpc);
1505 # else
1506                 fprintf(stderr, "syscall: unknown syscall trap %08lx %08lx\n", trap, sparc_regs.pc);
1507 # endif
1508                 return -1;
1509         }
1510
1511         /* Extract the system call number from the registers. */
1512         if (trap == 0x91d02027)
1513                 scno = 156;
1514         else
1515                 scno = sparc_regs.u_regs[U_REG_G1];
1516         if (scno == 0) {
1517                 scno = sparc_regs.u_regs[U_REG_O0];
1518                 memmove(&sparc_regs.u_regs[U_REG_O0], &sparc_regs.u_regs[U_REG_O1], 7*sizeof(sparc_regs.u_regs[0]));
1519         }
1520 #elif defined(HPPA)
1521         if (upeek(tcp->pid, PT_GR20, &scno) < 0)
1522                 return -1;
1523 #elif defined(SH)
1524         /*
1525          * In the new syscall ABI, the system call number is in R3.
1526          */
1527         if (upeek(tcp->pid, 4*(REG_REG0+3), &scno) < 0)
1528                 return -1;
1529
1530         if (scno < 0) {
1531                 /* Odd as it may seem, a glibc bug has been known to cause
1532                    glibc to issue bogus negative syscall numbers.  So for
1533                    our purposes, make strace print what it *should* have been */
1534                 long correct_scno = (scno & 0xff);
1535                 if (debug_flag)
1536                         fprintf(stderr,
1537                                 "Detected glibc bug: bogus system call"
1538                                 " number = %ld, correcting to %ld\n",
1539                                 scno,
1540                                 correct_scno);
1541                 scno = correct_scno;
1542         }
1543 #elif defined(SH64)
1544         if (upeek(tcp->pid, REG_SYSCALL, &scno) < 0)
1545                 return -1;
1546         scno &= 0xFFFF;
1547 #elif defined(CRISV10) || defined(CRISV32)
1548         if (upeek(tcp->pid, 4*PT_R9, &scno) < 0)
1549                 return -1;
1550 #elif defined(TILE)
1551         unsigned int currpers;
1552         scno = tile_regs.regs[10];
1553 # ifdef __tilepro__
1554         currpers = 1;
1555 # else
1556 #  ifndef PT_FLAGS_COMPAT
1557 #   define PT_FLAGS_COMPAT 0x10000  /* from Linux 3.8 on */
1558 #  endif
1559         if (tile_regs.flags & PT_FLAGS_COMPAT)
1560                 currpers = 1;
1561         else
1562                 currpers = 0;
1563 # endif
1564         update_personality(tcp, currpers);
1565 #elif defined(MICROBLAZE)
1566         if (upeek(tcp->pid, 0, &scno) < 0)
1567                 return -1;
1568 #elif defined(OR1K)
1569         scno = or1k_regs.gpr[11];
1570 #elif defined(METAG)
1571         scno = metag_regs.dx[0][1];     /* syscall number in D1Re0 (D1.0) */
1572 #elif defined(XTENSA)
1573         if (upeek(tcp->pid, SYSCALL_NR, &scno) < 0)
1574                 return -1;
1575 # elif defined(ARC)
1576         scno = arc_regs.scratch.r8;
1577 #endif
1578
1579         tcp->scno = scno;
1580         if (SCNO_IS_VALID(tcp->scno)) {
1581                 tcp->s_ent = &sysent[scno];
1582                 tcp->qual_flg = qual_flags[scno];
1583         } else {
1584                 static const struct_sysent unknown = {
1585                         .nargs = MAX_ARGS,
1586                         .sys_flags = 0,
1587                         .sys_func = printargs,
1588                         .sys_name = "unknown", /* not used */
1589                 };
1590                 tcp->s_ent = &unknown;
1591                 tcp->qual_flg = UNDEFINED_SCNO | QUAL_RAW | DEFAULT_QUAL_FLAGS;
1592         }
1593         return 1;
1594 }
1595
1596 /* Called at each syscall entry.
1597  * Returns:
1598  * 0: "ignore this ptrace stop", bail out of trace_syscall_entering() silently.
1599  * 1: ok, continue in trace_syscall_entering().
1600  * other: error, trace_syscall_entering() should print error indicator
1601  *    ("????" etc) and bail out.
1602  */
1603 static int
1604 syscall_fixup_on_sysenter(struct tcb *tcp)
1605 {
1606         /* A common case of "not a syscall entry" is post-execve SIGTRAP */
1607 #if defined(I386)
1608         /*
1609          * Syscall number -1 requires special treatment.
1610          * On X86, it might be a side effect of SECCOMP_RET_ERRNO filtering
1611          * that sets orig_eax to -1 in some versions of linux kernel.
1612          */
1613         if (i386_regs.orig_eax != -1 &&
1614             i386_regs.eax != -ENOSYS) {
1615                 if (debug_flag)
1616                         fprintf(stderr,
1617                                 "not a syscall entry (eax = %ld, orig_eax = %ld)\n",
1618                                 i386_regs.eax, i386_regs.orig_eax);
1619                 return 0;
1620         }
1621 #elif defined(X86_64) || defined(X32)
1622         /*
1623          * Syscall number -1 requires special treatment.
1624          * On X86_64/X32, it might be a side effect of SECCOMP_RET_ERRNO
1625          * filtering that sets orig_rax to -1 in some versions of linux kernel.
1626          */
1627         if (x86_io.iov_len == sizeof(i386_regs)) {
1628                 if ((int) i386_regs.orig_eax != -1 &&
1629                     (int) i386_regs.eax != -ENOSYS) {
1630                         if (debug_flag)
1631                                 fprintf(stderr,
1632                                         "not a syscall entry (eax = %d, orig_eax = %d)\n",
1633                                         (int) i386_regs.eax,
1634                                         (int) i386_regs.orig_eax);
1635                         return 0;
1636                 }
1637         } else {
1638                 if ((long long) x86_64_regs.orig_rax != -1 &&
1639                     (long long) x86_64_regs.rax != -ENOSYS) {
1640                         if (debug_flag)
1641                                 fprintf(stderr,
1642                                         "not a syscall entry (rax = %lld, orig_rax = %lld)\n",
1643                                         (long long) x86_64_regs.rax,
1644                                         (long long) x86_64_regs.orig_rax);
1645                         return 0;
1646                 }
1647         }
1648 #elif defined(M68K)
1649         /* TODO? Eliminate upeek's in arches below like we did in x86 */
1650         if (upeek(tcp->pid, 4*PT_D0, &m68k_d0) < 0)
1651                 return -1;
1652         if (m68k_d0 != -ENOSYS) {
1653                 if (debug_flag)
1654                         fprintf(stderr, "not a syscall entry (d0 = %ld)\n", m68k_d0);
1655                 return 0;
1656         }
1657 #elif defined(IA64)
1658         if (upeek(tcp->pid, PT_R10, &ia64_r10) < 0)
1659                 return -1;
1660         if (upeek(tcp->pid, PT_R8, &ia64_r8) < 0)
1661                 return -1;
1662         if (ia64_ia32mode && ia64_r8 != -ENOSYS) {
1663                 if (debug_flag)
1664                         fprintf(stderr, "not a syscall entry (r8 = %ld)\n", ia64_r8);
1665                 return 0;
1666         }
1667 #elif defined(CRISV10) || defined(CRISV32)
1668         if (upeek(tcp->pid, 4*PT_R10, &cris_r10) < 0)
1669                 return -1;
1670         if (cris_r10 != -ENOSYS) {
1671                 if (debug_flag)
1672                         fprintf(stderr, "not a syscall entry (r10 = %ld)\n", cris_r10);
1673                 return 0;
1674         }
1675 #elif defined(MICROBLAZE)
1676         if (upeek(tcp->pid, 3 * 4, &microblaze_r3) < 0)
1677                 return -1;
1678         if (microblaze_r3 != -ENOSYS) {
1679                 if (debug_flag)
1680                         fprintf(stderr, "not a syscall entry (r3 = %ld)\n", microblaze_r3);
1681                 return 0;
1682         }
1683 #endif
1684         return 1;
1685 }
1686
1687 static void
1688 internal_fork(struct tcb *tcp)
1689 {
1690 #if defined S390 || defined S390X || defined CRISV10 || defined CRISV32
1691 # define ARG_FLAGS      1
1692 #else
1693 # define ARG_FLAGS      0
1694 #endif
1695 #ifndef CLONE_UNTRACED
1696 # define CLONE_UNTRACED 0x00800000
1697 #endif
1698         if ((ptrace_setoptions
1699             & (PTRACE_O_TRACECLONE | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK))
1700            == (PTRACE_O_TRACECLONE | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK))
1701                 return;
1702
1703         if (!followfork)
1704                 return;
1705
1706         if (entering(tcp)) {
1707                 /*
1708                  * We won't see the new child if clone is called with
1709                  * CLONE_UNTRACED, so we keep the same logic with that option
1710                  * and don't trace it.
1711                  */
1712                 if ((tcp->s_ent->sys_func == sys_clone)
1713                  && (tcp->u_arg[ARG_FLAGS] & CLONE_UNTRACED)
1714                 )
1715                         return;
1716                 setbpt(tcp);
1717         } else {
1718                 if (tcp->flags & TCB_BPTSET)
1719                         clearbpt(tcp);
1720         }
1721 }
1722
1723 #if defined(TCB_WAITEXECVE)
1724 static void
1725 internal_exec(struct tcb *tcp)
1726 {
1727         /* Maybe we have post-execve SIGTRAP suppressed? */
1728         if (ptrace_setoptions & PTRACE_O_TRACEEXEC)
1729                 return; /* yes, no need to do anything */
1730
1731         if (exiting(tcp) && syserror(tcp))
1732                 /* Error in execve, no post-execve SIGTRAP expected */
1733                 tcp->flags &= ~TCB_WAITEXECVE;
1734         else
1735                 tcp->flags |= TCB_WAITEXECVE;
1736 }
1737 #endif
1738
1739 static void
1740 syscall_fixup_for_fork_exec(struct tcb *tcp)
1741 {
1742         /*
1743          * We must always trace a few critical system calls in order to
1744          * correctly support following forks in the presence of tracing
1745          * qualifiers.
1746          */
1747         int (*func)();
1748
1749         func = tcp->s_ent->sys_func;
1750
1751         if (   sys_fork == func
1752             || sys_clone == func
1753            ) {
1754                 internal_fork(tcp);
1755                 return;
1756         }
1757
1758 #if defined(TCB_WAITEXECVE)
1759         if (   sys_execve == func
1760 # if defined(SPARC) || defined(SPARC64)
1761             || sys_execv == func
1762 # endif
1763            ) {
1764                 internal_exec(tcp);
1765                 return;
1766         }
1767 #endif
1768 }
1769
1770 /* Return -1 on error or 1 on success (never 0!) */
1771 static int
1772 get_syscall_args(struct tcb *tcp)
1773 {
1774         int i, nargs;
1775
1776         nargs = tcp->s_ent->nargs;
1777
1778 #if defined(S390) || defined(S390X)
1779         for (i = 0; i < nargs; ++i)
1780                 if (upeek(tcp->pid, i==0 ? PT_ORIGGPR2 : PT_GPR2 + i*sizeof(long), &tcp->u_arg[i]) < 0)
1781                         return -1;
1782 #elif defined(ALPHA)
1783         for (i = 0; i < nargs; ++i)
1784                 if (upeek(tcp->pid, REG_A0+i, &tcp->u_arg[i]) < 0)
1785                         return -1;
1786 #elif defined(IA64)
1787         if (!ia64_ia32mode) {
1788                 unsigned long *out0, cfm, sof, sol;
1789                 long rbs_end;
1790                 /* be backwards compatible with kernel < 2.4.4... */
1791 #               ifndef PT_RBS_END
1792 #                 define PT_RBS_END     PT_AR_BSP
1793 #               endif
1794
1795                 if (upeek(tcp->pid, PT_RBS_END, &rbs_end) < 0)
1796                         return -1;
1797                 if (upeek(tcp->pid, PT_CFM, (long *) &cfm) < 0)
1798                         return -1;
1799
1800                 sof = (cfm >> 0) & 0x7f;
1801                 sol = (cfm >> 7) & 0x7f;
1802                 out0 = ia64_rse_skip_regs((unsigned long *) rbs_end, -sof + sol);
1803
1804                 for (i = 0; i < nargs; ++i) {
1805                         if (umoven(tcp, (unsigned long) ia64_rse_skip_regs(out0, i),
1806                                    sizeof(long), (char *) &tcp->u_arg[i]) < 0)
1807                                 return -1;
1808                 }
1809         } else {
1810                 static const int argreg[MAX_ARGS] = { PT_R11 /* EBX = out0 */,
1811                                                       PT_R9  /* ECX = out1 */,
1812                                                       PT_R10 /* EDX = out2 */,
1813                                                       PT_R14 /* ESI = out3 */,
1814                                                       PT_R15 /* EDI = out4 */,
1815                                                       PT_R13 /* EBP = out5 */};
1816
1817                 for (i = 0; i < nargs; ++i) {
1818                         if (upeek(tcp->pid, argreg[i], &tcp->u_arg[i]) < 0)
1819                                 return -1;
1820                         /* truncate away IVE sign-extension */
1821                         tcp->u_arg[i] &= 0xffffffff;
1822                 }
1823         }
1824 #elif defined(LINUX_MIPSN32) || defined(LINUX_MIPSN64)
1825         /* N32 and N64 both use up to six registers.  */
1826         unsigned long long regs[38];
1827
1828         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
1829                 return -1;
1830
1831         for (i = 0; i < nargs; ++i) {
1832                 tcp->u_arg[i] = regs[REG_A0 + i];
1833 # if defined(LINUX_MIPSN32)
1834                 tcp->ext_arg[i] = regs[REG_A0 + i];
1835 # endif
1836         }
1837 #elif defined(MIPS)
1838         if (nargs > 4) {
1839                 long sp;
1840
1841                 if (upeek(tcp->pid, REG_SP, &sp) < 0)
1842                         return -1;
1843                 for (i = 0; i < 4; ++i)
1844                         if (upeek(tcp->pid, REG_A0 + i, &tcp->u_arg[i]) < 0)
1845                                 return -1;
1846                 umoven(tcp, sp + 16, (nargs - 4) * sizeof(tcp->u_arg[0]),
1847                        (char *)(tcp->u_arg + 4));
1848         } else {
1849                 for (i = 0; i < nargs; ++i)
1850                         if (upeek(tcp->pid, REG_A0 + i, &tcp->u_arg[i]) < 0)
1851                                 return -1;
1852         }
1853 #elif defined(POWERPC)
1854         (void)i;
1855         (void)nargs;
1856         tcp->u_arg[0] = ppc_regs.orig_gpr3;
1857         tcp->u_arg[1] = ppc_regs.gpr[4];
1858         tcp->u_arg[2] = ppc_regs.gpr[5];
1859         tcp->u_arg[3] = ppc_regs.gpr[6];
1860         tcp->u_arg[4] = ppc_regs.gpr[7];
1861         tcp->u_arg[5] = ppc_regs.gpr[8];
1862 #elif defined(SPARC) || defined(SPARC64)
1863         for (i = 0; i < nargs; ++i)
1864                 tcp->u_arg[i] = sparc_regs.u_regs[U_REG_O0 + i];
1865 #elif defined(HPPA)
1866         for (i = 0; i < nargs; ++i)
1867                 if (upeek(tcp->pid, PT_GR26-4*i, &tcp->u_arg[i]) < 0)
1868                         return -1;
1869 #elif defined(ARM) || defined(AARCH64)
1870 # if defined(AARCH64)
1871         if (tcp->currpers == 1)
1872                 for (i = 0; i < nargs; ++i)
1873                         tcp->u_arg[i] = aarch64_regs.regs[i];
1874         else
1875 # endif
1876         for (i = 0; i < nargs; ++i)
1877                 tcp->u_arg[i] = arm_regs.uregs[i];
1878 #elif defined(AVR32)
1879         (void)i;
1880         (void)nargs;
1881         tcp->u_arg[0] = avr32_regs.r12;
1882         tcp->u_arg[1] = avr32_regs.r11;
1883         tcp->u_arg[2] = avr32_regs.r10;
1884         tcp->u_arg[3] = avr32_regs.r9;
1885         tcp->u_arg[4] = avr32_regs.r5;
1886         tcp->u_arg[5] = avr32_regs.r3;
1887 #elif defined(BFIN)
1888         static const int argreg[MAX_ARGS] = { PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5 };
1889
1890         for (i = 0; i < nargs; ++i)
1891                 if (upeek(tcp->pid, argreg[i], &tcp->u_arg[i]) < 0)
1892                         return -1;
1893 #elif defined(SH)
1894         static const int syscall_regs[MAX_ARGS] = {
1895                 4 * (REG_REG0+4), 4 * (REG_REG0+5), 4 * (REG_REG0+6),
1896                 4 * (REG_REG0+7), 4 * (REG_REG0  ), 4 * (REG_REG0+1)
1897         };
1898
1899         for (i = 0; i < nargs; ++i)
1900                 if (upeek(tcp->pid, syscall_regs[i], &tcp->u_arg[i]) < 0)
1901                         return -1;
1902 #elif defined(SH64)
1903         int i;
1904         /* Registers used by SH5 Linux system calls for parameters */
1905         static const int syscall_regs[MAX_ARGS] = { 2, 3, 4, 5, 6, 7 };
1906
1907         for (i = 0; i < nargs; ++i)
1908                 if (upeek(tcp->pid, REG_GENERAL(syscall_regs[i]), &tcp->u_arg[i]) < 0)
1909                         return -1;
1910 #elif defined(I386)
1911         (void)i;
1912         (void)nargs;
1913         tcp->u_arg[0] = i386_regs.ebx;
1914         tcp->u_arg[1] = i386_regs.ecx;
1915         tcp->u_arg[2] = i386_regs.edx;
1916         tcp->u_arg[3] = i386_regs.esi;
1917         tcp->u_arg[4] = i386_regs.edi;
1918         tcp->u_arg[5] = i386_regs.ebp;
1919 #elif defined(X86_64) || defined(X32)
1920         (void)i;
1921         (void)nargs;
1922         if (x86_io.iov_len != sizeof(i386_regs)) {
1923                 /* x86-64 or x32 ABI */
1924                 tcp->u_arg[0] = x86_64_regs.rdi;
1925                 tcp->u_arg[1] = x86_64_regs.rsi;
1926                 tcp->u_arg[2] = x86_64_regs.rdx;
1927                 tcp->u_arg[3] = x86_64_regs.r10;
1928                 tcp->u_arg[4] = x86_64_regs.r8;
1929                 tcp->u_arg[5] = x86_64_regs.r9;
1930 #  ifdef X32
1931                 tcp->ext_arg[0] = x86_64_regs.rdi;
1932                 tcp->ext_arg[1] = x86_64_regs.rsi;
1933                 tcp->ext_arg[2] = x86_64_regs.rdx;
1934                 tcp->ext_arg[3] = x86_64_regs.r10;
1935                 tcp->ext_arg[4] = x86_64_regs.r8;
1936                 tcp->ext_arg[5] = x86_64_regs.r9;
1937 #  endif
1938         } else {
1939                 /* i386 ABI */
1940                 /* Zero-extend from 32 bits */
1941                 /* Use widen_to_long(tcp->u_arg[N]) in syscall handlers
1942                  * if you need to use *sign-extended* parameter.
1943                  */
1944                 tcp->u_arg[0] = (long)(uint32_t)i386_regs.ebx;
1945                 tcp->u_arg[1] = (long)(uint32_t)i386_regs.ecx;
1946                 tcp->u_arg[2] = (long)(uint32_t)i386_regs.edx;
1947                 tcp->u_arg[3] = (long)(uint32_t)i386_regs.esi;
1948                 tcp->u_arg[4] = (long)(uint32_t)i386_regs.edi;
1949                 tcp->u_arg[5] = (long)(uint32_t)i386_regs.ebp;
1950         }
1951 #elif defined(MICROBLAZE)
1952         for (i = 0; i < nargs; ++i)
1953                 if (upeek(tcp->pid, (5 + i) * 4, &tcp->u_arg[i]) < 0)
1954                         return -1;
1955 #elif defined(CRISV10) || defined(CRISV32)
1956         static const int crisregs[MAX_ARGS] = {
1957                 4*PT_ORIG_R10, 4*PT_R11, 4*PT_R12,
1958                 4*PT_R13     , 4*PT_MOF, 4*PT_SRP
1959         };
1960
1961         for (i = 0; i < nargs; ++i)
1962                 if (upeek(tcp->pid, crisregs[i], &tcp->u_arg[i]) < 0)
1963                         return -1;
1964 #elif defined(TILE)
1965         for (i = 0; i < nargs; ++i)
1966                 tcp->u_arg[i] = tile_regs.regs[i];
1967 #elif defined(M68K)
1968         for (i = 0; i < nargs; ++i)
1969                 if (upeek(tcp->pid, (i < 5 ? i : i + 2)*4, &tcp->u_arg[i]) < 0)
1970                         return -1;
1971 #elif defined(OR1K)
1972         (void)nargs;
1973         for (i = 0; i < 6; ++i)
1974                 tcp->u_arg[i] = or1k_regs.gpr[3 + i];
1975 #elif defined(METAG)
1976         for (i = 0; i < nargs; i++)
1977                 /* arguments go backwards from D1Ar1 (D1.3) */
1978                 tcp->u_arg[i] = ((unsigned long *)&metag_regs.dx[3][1])[-i];
1979 #elif defined(XTENSA)
1980         /* arg0: a6, arg1: a3, arg2: a4, arg3: a5, arg4: a8, arg5: a9 */
1981         static const int xtensaregs[MAX_ARGS] = { 6, 3, 4, 5, 8, 9 };
1982         for (i = 0; i < nargs; ++i)
1983                 if (upeek(tcp->pid, REG_A_BASE + xtensaregs[i], &tcp->u_arg[i]) < 0)
1984                         return -1;
1985 # elif defined(ARC)
1986         long *arc_args = &arc_regs.scratch.r0;
1987         for (i = 0; i < nargs; ++i)
1988                 tcp->u_arg[i] = *arc_args--;
1989
1990 #else /* Other architecture (32bits specific) */
1991         for (i = 0; i < nargs; ++i)
1992                 if (upeek(tcp->pid, i*4, &tcp->u_arg[i]) < 0)
1993                         return -1;
1994 #endif
1995         return 1;
1996 }
1997
1998 static int
1999 trace_syscall_entering(struct tcb *tcp)
2000 {
2001         int res, scno_good;
2002
2003 #if defined TCB_WAITEXECVE
2004         if (tcp->flags & TCB_WAITEXECVE) {
2005                 /* This is the post-execve SIGTRAP. */
2006                 tcp->flags &= ~TCB_WAITEXECVE;
2007                 return 0;
2008         }
2009 #endif
2010
2011         scno_good = res = (get_regs_error ? -1 : get_scno(tcp));
2012         if (res == 0)
2013                 return res;
2014         if (res == 1) {
2015                 res = syscall_fixup_on_sysenter(tcp);
2016                 if (res == 0)
2017                         return res;
2018                 if (res == 1)
2019                         res = get_syscall_args(tcp);
2020         }
2021
2022         if (res != 1) {
2023                 printleader(tcp);
2024                 if (scno_good != 1)
2025                         tprints("????" /* anti-trigraph gap */ "(");
2026                 else if (tcp->qual_flg & UNDEFINED_SCNO)
2027                         tprintf("%s(", undefined_scno_name(tcp));
2028                 else
2029                         tprintf("%s(", tcp->s_ent->sys_name);
2030                 /*
2031                  * " <unavailable>" will be added later by the code which
2032                  * detects ptrace errors.
2033                  */
2034                 goto ret;
2035         }
2036
2037         if (   sys_execve == tcp->s_ent->sys_func
2038 # if defined(SPARC) || defined(SPARC64)
2039             || sys_execv == tcp->s_ent->sys_func
2040 # endif
2041            ) {
2042                 hide_log_until_execve = 0;
2043         }
2044
2045 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
2046         while (1) {
2047 # ifdef SYS_socket_subcall
2048                 if (tcp->s_ent->sys_func == sys_socketcall) {
2049                         decode_socket_subcall(tcp);
2050                         break;
2051                 }
2052 # endif
2053 # ifdef SYS_ipc_subcall
2054                 if (tcp->s_ent->sys_func == sys_ipc) {
2055                         decode_ipc_subcall(tcp);
2056                         break;
2057                 }
2058 # endif
2059                 break;
2060         }
2061 #endif
2062
2063         if (need_fork_exec_workarounds)
2064                 syscall_fixup_for_fork_exec(tcp);
2065
2066         if (!(tcp->qual_flg & QUAL_TRACE)
2067          || (tracing_paths && !pathtrace_match(tcp))
2068         ) {
2069                 tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
2070                 return 0;
2071         }
2072
2073         tcp->flags &= ~TCB_FILTERED;
2074
2075         if (cflag == CFLAG_ONLY_STATS || hide_log_until_execve) {
2076                 res = 0;
2077                 goto ret;
2078         }
2079
2080 #ifdef USE_LIBUNWIND
2081         if (stack_trace_enabled) {
2082                 if (tcp->s_ent->sys_flags & STACKTRACE_CAPTURE_ON_ENTER)
2083                         unwind_capture_stacktrace(tcp);
2084         }
2085 #endif
2086
2087         printleader(tcp);
2088         if (tcp->qual_flg & UNDEFINED_SCNO)
2089                 tprintf("%s(", undefined_scno_name(tcp));
2090         else
2091                 tprintf("%s(", tcp->s_ent->sys_name);
2092         if ((tcp->qual_flg & QUAL_RAW) && tcp->s_ent->sys_func != sys_exit)
2093                 res = printargs(tcp);
2094         else
2095                 res = tcp->s_ent->sys_func(tcp);
2096
2097         fflush(tcp->outf);
2098  ret:
2099         tcp->flags |= TCB_INSYSCALL;
2100         /* Measure the entrance time as late as possible to avoid errors. */
2101         if (Tflag || cflag)
2102                 gettimeofday(&tcp->etime, NULL);
2103         return res;
2104 }
2105
2106 /* Returns:
2107  * 1: ok, continue in trace_syscall_exiting().
2108  * -1: error, trace_syscall_exiting() should print error indicator
2109  *    ("????" etc) and bail out.
2110  */
2111 static int
2112 get_syscall_result(struct tcb *tcp)
2113 {
2114 #if defined(S390) || defined(S390X)
2115         if (upeek(tcp->pid, PT_GPR2, &s390_gpr2) < 0)
2116                 return -1;
2117 #elif defined(POWERPC)
2118         /* already done by get_regs */
2119 #elif defined(AVR32)
2120         /* already done by get_regs */
2121 #elif defined(BFIN)
2122         if (upeek(tcp->pid, PT_R0, &bfin_r0) < 0)
2123                 return -1;
2124 #elif defined(I386)
2125         /* already done by get_regs */
2126 #elif defined(X86_64) || defined(X32)
2127         /* already done by get_regs */
2128 #elif defined(IA64)
2129 #       define IA64_PSR_IS      ((long)1 << 34)
2130         long psr;
2131         if (upeek(tcp->pid, PT_CR_IPSR, &psr) >= 0)
2132                 ia64_ia32mode = ((psr & IA64_PSR_IS) != 0);
2133         if (upeek(tcp->pid, PT_R8, &ia64_r8) < 0)
2134                 return -1;
2135         if (upeek(tcp->pid, PT_R10, &ia64_r10) < 0)
2136                 return -1;
2137 #elif defined(ARM)
2138         /* already done by get_regs */
2139 #elif defined(AARCH64)
2140         /* register reading already done by get_regs */
2141
2142         /* Used to do this, but we did it on syscall entry already: */
2143         /* We are in 64-bit mode (personality 1) if register struct is aarch64_regs,
2144          * else it's personality 0.
2145          */
2146         /*update_personality(tcp, aarch64_io.iov_len == sizeof(aarch64_regs));*/
2147 #elif defined(M68K)
2148         if (upeek(tcp->pid, 4*PT_D0, &m68k_d0) < 0)
2149                 return -1;
2150 #elif defined(LINUX_MIPSN32)
2151         unsigned long long regs[38];
2152
2153         if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
2154                 return -1;
2155         mips_a3 = regs[REG_A3];
2156         mips_r2 = regs[REG_V0];
2157 #elif defined(MIPS)
2158         if (upeek(tcp->pid, REG_A3, &mips_a3) < 0)
2159                 return -1;
2160         if (upeek(tcp->pid, REG_V0, &mips_r2) < 0)
2161                 return -1;
2162 #elif defined(ALPHA)
2163         if (upeek(tcp->pid, REG_A3, &alpha_a3) < 0)
2164                 return -1;
2165         if (upeek(tcp->pid, REG_R0, &alpha_r0) < 0)
2166                 return -1;
2167 #elif defined(SPARC) || defined(SPARC64)
2168         /* already done by get_regs */
2169 #elif defined(HPPA)
2170         if (upeek(tcp->pid, PT_GR28, &hppa_r28) < 0)
2171                 return -1;
2172 #elif defined(SH)
2173         /* new syscall ABI returns result in R0 */
2174         if (upeek(tcp->pid, 4*REG_REG0, (long *)&sh_r0) < 0)
2175                 return -1;
2176 #elif defined(SH64)
2177         /* ABI defines result returned in r9 */
2178         if (upeek(tcp->pid, REG_GENERAL(9), (long *)&sh64_r9) < 0)
2179                 return -1;
2180 #elif defined(CRISV10) || defined(CRISV32)
2181         if (upeek(tcp->pid, 4*PT_R10, &cris_r10) < 0)
2182                 return -1;
2183 #elif defined(TILE)
2184         /* already done by get_regs */
2185 #elif defined(MICROBLAZE)
2186         if (upeek(tcp->pid, 3 * 4, &microblaze_r3) < 0)
2187                 return -1;
2188 #elif defined(OR1K)
2189         /* already done by get_regs */
2190 #elif defined(METAG)
2191         /* already done by get_regs */
2192 #elif defined(XTENSA)
2193         if (upeek(tcp->pid, REG_A_BASE + 2, &xtensa_a2) < 0)
2194                 return -1;
2195 #elif defined(ARC)
2196         /* already done by get_regs */
2197 #endif
2198         return 1;
2199 }
2200
2201 /* Called at each syscall exit */
2202 static void
2203 syscall_fixup_on_sysexit(struct tcb *tcp)
2204 {
2205 #if defined(S390) || defined(S390X)
2206         if ((tcp->flags & TCB_WAITEXECVE)
2207                  && (s390_gpr2 == -ENOSYS || s390_gpr2 == tcp->scno)) {
2208                 /*
2209                  * Return from execve.
2210                  * Fake a return value of zero.  We leave the TCB_WAITEXECVE
2211                  * flag set for the post-execve SIGTRAP to see and reset.
2212                  */
2213                 s390_gpr2 = 0;
2214         }
2215 #endif
2216 }
2217
2218 /*
2219  * Check the syscall return value register value for whether it is
2220  * a negated errno code indicating an error, or a success return value.
2221  */
2222 #ifndef X32
2223 static inline int
2224 is_negated_errno(unsigned long int val)
2225 {
2226         unsigned long int max = -(long int) nerrnos;
2227 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
2228         if (current_wordsize < sizeof(val)) {
2229                 val = (unsigned int) val;
2230                 max = (unsigned int) max;
2231         }
2232 #endif
2233         return val > max;
2234 }
2235
2236 #else /* X32 */
2237
2238 static inline int
2239 is_negated_errno(unsigned long long val)
2240 {
2241         unsigned long long max = -(long long) nerrnos;
2242         /*
2243          * current_wordsize is 4 even in personality 0 (native X32)
2244          * but truncation _must not_ be done in it.
2245          * can't check current_wordsize here!
2246          */
2247         if (current_personality != 0) {
2248                 val = (uint32_t) val;
2249                 max = (uint32_t) max;
2250         }
2251         return val > max;
2252 }
2253 #endif /* X32 */
2254
2255 /* Returns:
2256  * 1: ok, continue in trace_syscall_exiting().
2257  * -1: error, trace_syscall_exiting() should print error indicator
2258  *    ("????" etc) and bail out.
2259  */
2260 static void
2261 get_error(struct tcb *tcp)
2262 {
2263         int u_error = 0;
2264         int check_errno = 1;
2265         if (tcp->s_ent->sys_flags & SYSCALL_NEVER_FAILS) {
2266                 check_errno = 0;
2267         }
2268 #if defined(S390) || defined(S390X)
2269         if (check_errno && is_negated_errno(s390_gpr2)) {
2270                 tcp->u_rval = -1;
2271                 u_error = -s390_gpr2;
2272         }
2273         else {
2274                 tcp->u_rval = s390_gpr2;
2275         }
2276 #elif defined(I386)
2277         if (check_errno && is_negated_errno(i386_regs.eax)) {
2278                 tcp->u_rval = -1;
2279                 u_error = -i386_regs.eax;
2280         }
2281         else {
2282                 tcp->u_rval = i386_regs.eax;
2283         }
2284 #elif defined(X86_64)
2285         long rax;
2286         if (x86_io.iov_len == sizeof(i386_regs)) {
2287                 /* Sign extend from 32 bits */
2288                 rax = (int32_t)i386_regs.eax;
2289         } else {
2290                 rax = x86_64_regs.rax;
2291         }
2292         if (check_errno && is_negated_errno(rax)) {
2293                 tcp->u_rval = -1;
2294                 u_error = -rax;
2295         }
2296         else {
2297                 tcp->u_rval = rax;
2298         }
2299 #elif defined(X32)
2300         /* In X32, return value is 64-bit (llseek uses one).
2301          * Using merely "long rax" would not work.
2302          */
2303         long long rax;
2304         if (x86_io.iov_len == sizeof(i386_regs)) {
2305                 /* Sign extend from 32 bits */
2306                 rax = (int32_t)i386_regs.eax;
2307         } else {
2308                 rax = x86_64_regs.rax;
2309         }
2310         if (check_errno && is_negated_errno(rax)) {
2311                 tcp->u_rval = -1;
2312                 u_error = -rax;
2313         }
2314         else {
2315                 tcp->u_rval = rax; /* truncating */
2316                 tcp->u_lrval = rax;
2317         }
2318 #elif defined(IA64)
2319         if (ia64_ia32mode) {
2320                 int err;
2321
2322                 err = (int)ia64_r8;
2323                 if (check_errno && is_negated_errno(err)) {
2324                         tcp->u_rval = -1;
2325                         u_error = -err;
2326                 }
2327                 else {
2328                         tcp->u_rval = err;
2329                 }
2330         } else {
2331                 if (check_errno && ia64_r10) {
2332                         tcp->u_rval = -1;
2333                         u_error = ia64_r8;
2334                 } else {
2335                         tcp->u_rval = ia64_r8;
2336                 }
2337         }
2338 #elif defined(MIPS)
2339         if (check_errno && mips_a3) {
2340                 tcp->u_rval = -1;
2341                 u_error = mips_r2;
2342         } else {
2343                 tcp->u_rval = mips_r2;
2344 # if defined(LINUX_MIPSN32)
2345                 tcp->u_lrval = mips_r2;
2346 # endif
2347         }
2348 #elif defined(POWERPC)
2349         if (check_errno && (ppc_regs.ccr & 0x10000000)) {
2350                 tcp->u_rval = -1;
2351                 u_error = ppc_regs.gpr[3];
2352         }
2353         else {
2354                 tcp->u_rval = ppc_regs.gpr[3];
2355         }
2356 #elif defined(M68K)
2357         if (check_errno && is_negated_errno(m68k_d0)) {
2358                 tcp->u_rval = -1;
2359                 u_error = -m68k_d0;
2360         }
2361         else {
2362                 tcp->u_rval = m68k_d0;
2363         }
2364 #elif defined(ARM) || defined(AARCH64)
2365 # if defined(AARCH64)
2366         if (tcp->currpers == 1) {
2367                 if (check_errno && is_negated_errno(aarch64_regs.regs[0])) {
2368                         tcp->u_rval = -1;
2369                         u_error = -aarch64_regs.regs[0];
2370                 }
2371                 else {
2372                         tcp->u_rval = aarch64_regs.regs[0];
2373                 }
2374         }
2375         else
2376 # endif
2377         {
2378                 if (check_errno && is_negated_errno(arm_regs.ARM_r0)) {
2379                         tcp->u_rval = -1;
2380                         u_error = -arm_regs.ARM_r0;
2381                 }
2382                 else {
2383                         tcp->u_rval = arm_regs.ARM_r0;
2384                 }
2385         }
2386 #elif defined(AVR32)
2387         if (check_errno && avr32_regs.r12 && (unsigned) -avr32_regs.r12 < nerrnos) {
2388                 tcp->u_rval = -1;
2389                 u_error = -avr32_regs.r12;
2390         }
2391         else {
2392                 tcp->u_rval = avr32_regs.r12;
2393         }
2394 #elif defined(BFIN)
2395         if (check_errno && is_negated_errno(bfin_r0)) {
2396                 tcp->u_rval = -1;
2397                 u_error = -bfin_r0;
2398         } else {
2399                 tcp->u_rval = bfin_r0;
2400         }
2401 #elif defined(ALPHA)
2402         if (check_errno && alpha_a3) {
2403                 tcp->u_rval = -1;
2404                 u_error = alpha_r0;
2405         }
2406         else {
2407                 tcp->u_rval = alpha_r0;
2408         }
2409 #elif defined(SPARC)
2410         if (check_errno && sparc_regs.psr & PSR_C) {
2411                 tcp->u_rval = -1;
2412                 u_error = sparc_regs.u_regs[U_REG_O0];
2413         }
2414         else {
2415                 tcp->u_rval = sparc_regs.u_regs[U_REG_O0];
2416         }
2417 #elif defined(SPARC64)
2418         if (check_errno && sparc_regs.tstate & 0x1100000000UL) {
2419                 tcp->u_rval = -1;
2420                 u_error = sparc_regs.u_regs[U_REG_O0];
2421         }
2422         else {
2423                 tcp->u_rval = sparc_regs.u_regs[U_REG_O0];
2424         }
2425 #elif defined(HPPA)
2426         if (check_errno && is_negated_errno(hppa_r28)) {
2427                 tcp->u_rval = -1;
2428                 u_error = -hppa_r28;
2429         }
2430         else {
2431                 tcp->u_rval = hppa_r28;
2432         }
2433 #elif defined(SH)
2434         if (check_errno && is_negated_errno(sh_r0)) {
2435                 tcp->u_rval = -1;
2436                 u_error = -sh_r0;
2437         }
2438         else {
2439                 tcp->u_rval = sh_r0;
2440         }
2441 #elif defined(SH64)
2442         if (check_errno && is_negated_errno(sh64_r9)) {
2443                 tcp->u_rval = -1;
2444                 u_error = -sh64_r9;
2445         }
2446         else {
2447                 tcp->u_rval = sh64_r9;
2448         }
2449 #elif defined(METAG)
2450         /* result pointer in D0Re0 (D0.0) */
2451         if (check_errno && is_negated_errno(metag_regs.dx[0][0])) {
2452                 tcp->u_rval = -1;
2453                 u_error = -metag_regs.dx[0][0];
2454         }
2455         else {
2456                 tcp->u_rval = metag_regs.dx[0][0];
2457         }
2458 #elif defined(CRISV10) || defined(CRISV32)
2459         if (check_errno && cris_r10 && (unsigned) -cris_r10 < nerrnos) {
2460                 tcp->u_rval = -1;
2461                 u_error = -cris_r10;
2462         }
2463         else {
2464                 tcp->u_rval = cris_r10;
2465         }
2466 #elif defined(TILE)
2467         /*
2468          * The standard tile calling convention returns the value (or negative
2469          * errno) in r0, and zero (or positive errno) in r1.
2470          * Until at least kernel 3.8, however, the r1 value is not reflected
2471          * in ptregs at this point, so we use r0 here.
2472          */
2473         if (check_errno && is_negated_errno(tile_regs.regs[0])) {
2474                 tcp->u_rval = -1;
2475                 u_error = -tile_regs.regs[0];
2476         } else {
2477                 tcp->u_rval = tile_regs.regs[0];
2478         }
2479 #elif defined(MICROBLAZE)
2480         if (check_errno && is_negated_errno(microblaze_r3)) {
2481                 tcp->u_rval = -1;
2482                 u_error = -microblaze_r3;
2483         }
2484         else {
2485                 tcp->u_rval = microblaze_r3;
2486         }
2487 #elif defined(OR1K)
2488         if (check_errno && is_negated_errno(or1k_regs.gpr[11])) {
2489                 tcp->u_rval = -1;
2490                 u_error = -or1k_regs.gpr[11];
2491         }
2492         else {
2493                 tcp->u_rval = or1k_regs.gpr[11];
2494         }
2495 #elif defined(XTENSA)
2496         if (check_errno && is_negated_errno(xtensa_a2)) {
2497                 tcp->u_rval = -1;
2498                 u_error = -xtensa_a2;
2499         }
2500         else {
2501                 tcp->u_rval = xtensa_a2;
2502         }
2503 #elif defined(ARC)
2504         if (check_errno && is_negated_errno(arc_regs.scratch.r0)) {
2505                 tcp->u_rval = -1;
2506                 u_error = -arc_regs.scratch.r0;
2507         }
2508         else {
2509                 tcp->u_rval = arc_regs.scratch.r0;
2510         }
2511 #endif
2512         tcp->u_error = u_error;
2513 }
2514
2515 static void
2516 dumpio(struct tcb *tcp)
2517 {
2518         int (*func)();
2519
2520         if (syserror(tcp))
2521                 return;
2522         if ((unsigned long) tcp->u_arg[0] >= num_quals)
2523                 return;
2524         func = tcp->s_ent->sys_func;
2525         if (func == printargs)
2526                 return;
2527         if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
2528                 if (func == sys_read ||
2529                     func == sys_pread ||
2530                     func == sys_recv ||
2531                     func == sys_recvfrom) {
2532                         dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
2533                         return;
2534                 } else if (func == sys_readv) {
2535                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
2536                         return;
2537 #if HAVE_SENDMSG
2538                 } else if (func == sys_recvmsg) {
2539                         dumpiov_in_msghdr(tcp, tcp->u_arg[1]);
2540                         return;
2541                 } else if (func == sys_recvmmsg) {
2542                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
2543                         return;
2544 #endif
2545                 }
2546         }
2547         if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
2548                 if (func == sys_write ||
2549                     func == sys_pwrite ||
2550                     func == sys_send ||
2551                     func == sys_sendto)
2552                         dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
2553                 else if (func == sys_writev)
2554                         dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
2555 #if HAVE_SENDMSG
2556                 else if (func == sys_sendmsg)
2557                         dumpiov_in_msghdr(tcp, tcp->u_arg[1]);
2558                 else if (func == sys_sendmmsg)
2559                         dumpiov_in_mmsghdr(tcp, tcp->u_arg[1]);
2560 #endif
2561         }
2562 }
2563
2564 static int
2565 trace_syscall_exiting(struct tcb *tcp)
2566 {
2567         int sys_res;
2568         struct timeval tv;
2569         int res;
2570         long u_error;
2571
2572         /* Measure the exit time as early as possible to avoid errors. */
2573         if (Tflag || cflag)
2574                 gettimeofday(&tv, NULL);
2575
2576 #ifdef USE_LIBUNWIND
2577         if (stack_trace_enabled) {
2578                 if (tcp->s_ent->sys_flags & STACKTRACE_INVALIDATE_CACHE)
2579                         unwind_cache_invalidate(tcp);
2580         }
2581 #endif
2582
2583 #if SUPPORTED_PERSONALITIES > 1
2584         update_personality(tcp, tcp->currpers);
2585 #endif
2586         res = (get_regs_error ? -1 : get_syscall_result(tcp));
2587         if (res == 1) {
2588                 syscall_fixup_on_sysexit(tcp); /* never fails */
2589                 get_error(tcp); /* never fails */
2590                 if (need_fork_exec_workarounds)
2591                         syscall_fixup_for_fork_exec(tcp);
2592                 if (filtered(tcp) || hide_log_until_execve)
2593                         goto ret;
2594         }
2595
2596         if (cflag) {
2597                 count_syscall(tcp, &tv);
2598                 if (cflag == CFLAG_ONLY_STATS) {
2599                         goto ret;
2600                 }
2601         }
2602
2603         /* If not in -ff mode, and printing_tcp != tcp,
2604          * then the log currently does not end with output
2605          * of _our syscall entry_, but with something else.
2606          * We need to say which syscall's return is this.
2607          *
2608          * Forced reprinting via TCB_REPRINT is used only by
2609          * "strace -ff -oLOG test/threaded_execve" corner case.
2610          * It's the only case when -ff mode needs reprinting.
2611          */
2612         if ((followfork < 2 && printing_tcp != tcp) || (tcp->flags & TCB_REPRINT)) {
2613                 tcp->flags &= ~TCB_REPRINT;
2614                 printleader(tcp);
2615                 if (tcp->qual_flg & UNDEFINED_SCNO)
2616                         tprintf("<... %s resumed> ", undefined_scno_name(tcp));
2617                 else
2618                         tprintf("<... %s resumed> ", tcp->s_ent->sys_name);
2619         }
2620         printing_tcp = tcp;
2621
2622         if (res != 1) {
2623                 /* There was error in one of prior ptrace ops */
2624                 tprints(") ");
2625                 tabto();
2626                 tprints("= ? <unavailable>\n");
2627                 line_ended();
2628                 tcp->flags &= ~TCB_INSYSCALL;
2629                 return res;
2630         }
2631
2632         sys_res = 0;
2633         if (tcp->qual_flg & QUAL_RAW) {
2634                 /* sys_res = printargs(tcp); - but it's nop on sysexit */
2635         } else {
2636         /* FIXME: not_failing_only (IOW, option -z) is broken:
2637          * failure of syscall is known only after syscall return.
2638          * Thus we end up with something like this on, say, ENOENT:
2639          *     open("doesnt_exist", O_RDONLY <unfinished ...>
2640          *     {next syscall decode}
2641          * whereas the intended result is that open(...) line
2642          * is not shown at all.
2643          */
2644                 if (not_failing_only && tcp->u_error)
2645                         goto ret;       /* ignore failed syscalls */
2646                 sys_res = tcp->s_ent->sys_func(tcp);
2647         }
2648
2649         tprints(") ");
2650         tabto();
2651         u_error = tcp->u_error;
2652         if (tcp->qual_flg & QUAL_RAW) {
2653                 if (u_error)
2654                         tprintf("= -1 (errno %ld)", u_error);
2655                 else
2656                         tprintf("= %#lx", tcp->u_rval);
2657         }
2658         else if (!(sys_res & RVAL_NONE) && u_error) {
2659                 switch (u_error) {
2660                 /* Blocked signals do not interrupt any syscalls.
2661                  * In this case syscalls don't return ERESTARTfoo codes.
2662                  *
2663                  * Deadly signals set to SIG_DFL interrupt syscalls
2664                  * and kill the process regardless of which of the codes below
2665                  * is returned by the interrupted syscall.
2666                  * In some cases, kernel forces a kernel-generated deadly
2667                  * signal to be unblocked and set to SIG_DFL (and thus cause
2668                  * death) if it is blocked or SIG_IGNed: for example, SIGSEGV
2669                  * or SIGILL. (The alternative is to leave process spinning
2670                  * forever on the faulty instruction - not useful).
2671                  *
2672                  * SIG_IGNed signals and non-deadly signals set to SIG_DFL
2673                  * (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
2674                  * but kernel will always restart them.
2675                  */
2676                 case ERESTARTSYS:
2677                         /* Most common type of signal-interrupted syscall exit code.
2678                          * The system call will be restarted with the same arguments
2679                          * if SA_RESTART is set; otherwise, it will fail with EINTR.
2680                          */
2681                         tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
2682                         break;
2683                 case ERESTARTNOINTR:
2684                         /* Rare. For example, fork() returns this if interrupted.
2685                          * SA_RESTART is ignored (assumed set): the restart is unconditional.
2686                          */
2687                         tprints("= ? ERESTARTNOINTR (To be restarted)");
2688                         break;
2689                 case ERESTARTNOHAND:
2690                         /* pause(), rt_sigsuspend() etc use this code.
2691                          * SA_RESTART is ignored (assumed not set):
2692                          * syscall won't restart (will return EINTR instead)
2693                          * even after signal with SA_RESTART set. However,
2694                          * after SIG_IGN or SIG_DFL signal it will restart
2695                          * (thus the name "restart only if has no handler").
2696                          */
2697                         tprints("= ? ERESTARTNOHAND (To be restarted if no handler)");
2698                         break;
2699                 case ERESTART_RESTARTBLOCK:
2700                         /* Syscalls like nanosleep(), poll() which can't be
2701                          * restarted with their original arguments use this
2702                          * code. Kernel will execute restart_syscall() instead,
2703                          * which changes arguments before restarting syscall.
2704                          * SA_RESTART is ignored (assumed not set) similarly
2705                          * to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
2706                          * since restart data is saved in "restart block"
2707                          * in task struct, and if signal handler uses a syscall
2708                          * which in turn saves another such restart block,
2709                          * old data is lost and restart becomes impossible)
2710                          */
2711                         tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
2712                         break;
2713                 default:
2714                         if (u_error < 0)
2715                                 tprintf("= -1 E??? (errno %ld)", u_error);
2716                         else if ((unsigned long) u_error < nerrnos)
2717                                 tprintf("= -1 %s (%s)", errnoent[u_error],
2718                                         strerror(u_error));
2719                         else
2720                                 tprintf("= -1 ERRNO_%ld (%s)", u_error,
2721                                         strerror(u_error));
2722                         break;
2723                 }
2724                 if ((sys_res & RVAL_STR) && tcp->auxstr)
2725                         tprintf(" (%s)", tcp->auxstr);
2726         }
2727         else {
2728                 if (sys_res & RVAL_NONE)
2729                         tprints("= ?");
2730                 else {
2731                         switch (sys_res & RVAL_MASK) {
2732                         case RVAL_HEX:
2733                                 tprintf("= %#lx", tcp->u_rval);
2734                                 break;
2735                         case RVAL_OCTAL:
2736                                 tprintf("= %#lo", tcp->u_rval);
2737                                 break;
2738                         case RVAL_UDECIMAL:
2739                                 tprintf("= %lu", tcp->u_rval);
2740                                 break;
2741                         case RVAL_DECIMAL:
2742                                 tprintf("= %ld", tcp->u_rval);
2743                                 break;
2744                         case RVAL_FD:
2745                                 if (show_fd_path) {
2746                                         tprints("= ");
2747                                         printfd(tcp, tcp->u_rval);
2748                                 }
2749                                 else
2750                                         tprintf("= %ld", tcp->u_rval);
2751                                 break;
2752 #if defined(LINUX_MIPSN32) || defined(X32)
2753                         /*
2754                         case RVAL_LHEX:
2755                                 tprintf("= %#llx", tcp->u_lrval);
2756                                 break;
2757                         case RVAL_LOCTAL:
2758                                 tprintf("= %#llo", tcp->u_lrval);
2759                                 break;
2760                         */
2761                         case RVAL_LUDECIMAL:
2762                                 tprintf("= %llu", tcp->u_lrval);
2763                                 break;
2764                         /*
2765                         case RVAL_LDECIMAL:
2766                                 tprintf("= %lld", tcp->u_lrval);
2767                                 break;
2768                         */
2769 #endif
2770                         default:
2771                                 fprintf(stderr,
2772                                         "invalid rval format\n");
2773                                 break;
2774                         }
2775                 }
2776                 if ((sys_res & RVAL_STR) && tcp->auxstr)
2777                         tprintf(" (%s)", tcp->auxstr);
2778         }
2779         if (Tflag) {
2780                 tv_sub(&tv, &tv, &tcp->etime);
2781                 tprintf(" <%ld.%06ld>",
2782                         (long) tv.tv_sec, (long) tv.tv_usec);
2783         }
2784         tprints("\n");
2785         dumpio(tcp);
2786         line_ended();
2787
2788 #ifdef USE_LIBUNWIND
2789         if (stack_trace_enabled)
2790                 unwind_print_stacktrace(tcp);
2791 #endif
2792
2793  ret:
2794         tcp->flags &= ~TCB_INSYSCALL;
2795         return 0;
2796 }
2797
2798 int
2799 trace_syscall(struct tcb *tcp)
2800 {
2801         return exiting(tcp) ?
2802                 trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
2803 }