glebfm/strace
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
fe585656f8
strace/syscall.c
Denys Vlasenko fe585656f8 Make ERESTARTxyz messages more descriptive 
There is widespread confusion about exact meaning
of ERESTARTxyz codes. Before this change, we were showing
all four of them the same: as "(To be restarted)".

This change prints better explanations for these codes,
and contains verbose comments which explain *why* we display
codes that way - or else someone confused
is bound to come later and mangle them again.
New messages are:

ERESTARTSYS (To be restarted if SA_RESTART is set)
ERESTARTNOINTR (To be restarted)
ERESTARTNOHAND (Interrupted by signal)
ERESTART_RESTARTBLOCK (Interrupted by signal)

* syscall.c (trace_syscall_exiting): Make ERESTARTxyz messages
more descriptive.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
2012-01-12 11:26:34 +01:00

2543 lines
61 KiB
C
Raw Blame History

/*
* Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
* Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
* Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
* Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
* Copyright (c) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Linux for s390 port by D.J. Barrow
* <barrow_dj@mail.yahoo.com,djbarrow@de.ibm.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id$
*/
#include "defs.h"
#include <signal.h>
#include <time.h>
#include <errno.h>
#include <sys/user.h>
#include <sys/syscall.h>
#include <sys/param.h>
#ifdef HAVE_SYS_REG_H
#include <sys/reg.h>
#ifndef PTRACE_PEEKUSR
# define PTRACE_PEEKUSR PTRACE_PEEKUSER
#endif
#elif defined(HAVE_LINUX_PTRACE_H)
#undef PTRACE_SYSCALL
# ifdef HAVE_STRUCT_IA64_FPREG
# define ia64_fpreg XXX_ia64_fpreg
# endif
# ifdef HAVE_STRUCT_PT_ALL_USER_REGS
# define pt_all_user_regs XXX_pt_all_user_regs
# endif
#include <linux/ptrace.h>
# undef ia64_fpreg
# undef pt_all_user_regs
#endif
#if defined (LINUX) && defined (SPARC64)
# undef PTRACE_GETREGS
# define PTRACE_GETREGS PTRACE_GETREGS64
# undef PTRACE_SETREGS
# define PTRACE_SETREGS PTRACE_SETREGS64
#endif /* LINUX && SPARC64 */
#if defined(LINUX) && defined(IA64)
# include <asm/ptrace_offsets.h>
# include <asm/rse.h>
#endif
#define NR_SYSCALL_BASE 0
#ifdef LINUX
#ifndef ERESTARTSYS
#define ERESTARTSYS 512
#endif
#ifndef ERESTARTNOINTR
#define ERESTARTNOINTR 513
#endif
#ifndef ERESTARTNOHAND
#define ERESTARTNOHAND 514 /* restart if no handler.. */
#endif
#ifndef ENOIOCTLCMD
#define ENOIOCTLCMD 515 /* No ioctl command */
#endif
#ifndef ERESTART_RESTARTBLOCK
#define ERESTART_RESTARTBLOCK 516 /* restart by calling sys_restart_syscall */
#endif
#ifndef NSIG
#warning: NSIG is not defined, using 32
#define NSIG 32
#endif
#ifdef ARM
/* Ugh. Is this really correct? ARM has no RT signals?! */
#undef NSIG
#define NSIG 32
#undef NR_SYSCALL_BASE
#define NR_SYSCALL_BASE __NR_SYSCALL_BASE
#endif
#endif /* LINUX */
#include "syscall.h"
/* Define these shorthand notations to simplify the syscallent files. */
#define TD TRACE_DESC
#define TF TRACE_FILE
#define TI TRACE_IPC
#define TN TRACE_NETWORK
#define TP TRACE_PROCESS
#define TS TRACE_SIGNAL
#define NF SYSCALL_NEVER_FAILS
#define MA MAX_ARGS
static const struct sysent sysent0[] = {
#include "syscallent.h"
};
#if SUPPORTED_PERSONALITIES >= 2
static const struct sysent sysent1[] = {
#include "syscallent1.h"
};
#endif
#if SUPPORTED_PERSONALITIES >= 3
static const struct sysent sysent2[] = {
#include "syscallent2.h"
};
#endif
/* Now undef them since short defines cause wicked namespace pollution. */
#undef TD
#undef TF
#undef TI
#undef TN
#undef TP
#undef TS
#undef NF
#undef MA
/*
* `ioctlent.h' may be generated from `ioctlent.raw' by the auxiliary
* program `ioctlsort', such that the list is sorted by the `code' field.
* This has the side-effect of resolving the _IO.. macros into
* plain integers, eliminating the need to include here everything
* in "/usr/include".
*/
static const char *const errnoent0[] = {
#include "errnoent.h"
};
static const char *const signalent0[] = {
#include "signalent.h"
};
static const struct ioctlent ioctlent0[] = {
#include "ioctlent.h"
};
enum { nsyscalls0 = ARRAY_SIZE(sysent0) };
enum { nerrnos0 = ARRAY_SIZE(errnoent0) };
enum { nsignals0 = ARRAY_SIZE(signalent0) };
enum { nioctlents0 = ARRAY_SIZE(ioctlent0) };
int qual_flags0[MAX_QUALS];
#if SUPPORTED_PERSONALITIES >= 2
static const char *const errnoent1[] = {
#include "errnoent1.h"
};
static const char *const signalent1[] = {
#include "signalent1.h"
};
static const struct ioctlent ioctlent1[] = {
#include "ioctlent1.h"
};
enum { nsyscalls1 = ARRAY_SIZE(sysent1) };
enum { nerrnos1 = ARRAY_SIZE(errnoent1) };
enum { nsignals1 = ARRAY_SIZE(signalent1) };
enum { nioctlents1 = ARRAY_SIZE(ioctlent1) };
int qual_flags1[MAX_QUALS];
#endif
#if SUPPORTED_PERSONALITIES >= 3
static const char *const errnoent2[] = {
#include "errnoent2.h"
};
static const char *const signalent2[] = {
#include "signalent2.h"
};
static const struct ioctlent ioctlent2[] = {
#include "ioctlent2.h"
};
enum { nsyscalls2 = ARRAY_SIZE(sysent2) };
enum { nerrnos2 = ARRAY_SIZE(errnoent2) };
enum { nsignals2 = ARRAY_SIZE(signalent2) };
enum { nioctlents2 = ARRAY_SIZE(ioctlent2) };
int qual_flags2[MAX_QUALS];
#endif
const struct sysent *sysent;
const char *const *errnoent;
const char *const *signalent;
const struct ioctlent *ioctlent;
unsigned nsyscalls;
unsigned nerrnos;
unsigned nsignals;
unsigned nioctlents;
int *qual_flags;
int current_personality;
#ifndef PERSONALITY0_WORDSIZE
# define PERSONALITY0_WORDSIZE sizeof(long)
#endif
const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
PERSONALITY0_WORDSIZE,
#if SUPPORTED_PERSONALITIES > 1
PERSONALITY1_WORDSIZE,
#endif
#if SUPPORTED_PERSONALITIES > 2
PERSONALITY2_WORDSIZE,
#endif
};
void
set_personality(int personality)
{
switch (personality) {
case 0:
errnoent = errnoent0;
nerrnos = nerrnos0;
sysent = sysent0;
nsyscalls = nsyscalls0;
ioctlent = ioctlent0;
nioctlents = nioctlents0;
signalent = signalent0;
nsignals = nsignals0;
qual_flags = qual_flags0;
break;
#if SUPPORTED_PERSONALITIES >= 2
case 1:
errnoent = errnoent1;
nerrnos = nerrnos1;
sysent = sysent1;
nsyscalls = nsyscalls1;
ioctlent = ioctlent1;
nioctlents = nioctlents1;
signalent = signalent1;
nsignals = nsignals1;
qual_flags = qual_flags1;
break;
#endif
#if SUPPORTED_PERSONALITIES >= 3
case 2:
errnoent = errnoent2;
nerrnos = nerrnos2;
sysent = sysent2;
nsyscalls = nsyscalls2;
ioctlent = ioctlent2;
nioctlents = nioctlents2;
signalent = signalent2;
nsignals = nsignals2;
qual_flags = qual_flags2;
break;
#endif
}
current_personality = personality;
}
#if SUPPORTED_PERSONALITIES > 1
static void
update_personality(struct tcb *tcp, int personality)
{
if (personality == current_personality)
return;
set_personality(personality);
if (personality == tcp->currpers)
return;
tcp->currpers = personality;
#if defined(POWERPC64) || defined(X86_64)
if (!qflag) {
static const char *const names[] = {"64 bit", "32 bit"};
fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
tcp->pid, names[personality]);
}
#endif
}
#endif
static int qual_syscall(), qual_signal(), qual_fault(), qual_desc();
static const struct qual_options {
int bitflag;
const char *option_name;
int (*qualify)(const char *, int, int);
const char *argument_name;
} qual_options[] = {
{ QUAL_TRACE, "trace", qual_syscall, "system call" },
{ QUAL_TRACE, "t", qual_syscall, "system call" },
{ QUAL_ABBREV, "abbrev", qual_syscall, "system call" },
{ QUAL_ABBREV, "a", qual_syscall, "system call" },
{ QUAL_VERBOSE, "verbose", qual_syscall, "system call" },
{ QUAL_VERBOSE, "v", qual_syscall, "system call" },
{ QUAL_RAW, "raw", qual_syscall, "system call" },
{ QUAL_RAW, "x", qual_syscall, "system call" },
{ QUAL_SIGNAL, "signal", qual_signal, "signal" },
{ QUAL_SIGNAL, "signals", qual_signal, "signal" },
{ QUAL_SIGNAL, "s", qual_signal, "signal" },
{ QUAL_FAULT, "fault", qual_fault, "fault" },
{ QUAL_FAULT, "faults", qual_fault, "fault" },
{ QUAL_FAULT, "m", qual_fault, "fault" },
{ QUAL_READ, "read", qual_desc, "descriptor" },
{ QUAL_READ, "reads", qual_desc, "descriptor" },
{ QUAL_READ, "r", qual_desc, "descriptor" },
{ QUAL_WRITE, "write", qual_desc, "descriptor" },
{ QUAL_WRITE, "writes", qual_desc, "descriptor" },
{ QUAL_WRITE, "w", qual_desc, "descriptor" },
{ 0, NULL, NULL, NULL },
};
static void
qualify_one(int n, int bitflag, int not, int pers)
{
if (pers == 0 || pers < 0) {
if (not)
qual_flags0[n] &= ~bitflag;
else
qual_flags0[n] |= bitflag;
}
#if SUPPORTED_PERSONALITIES >= 2
if (pers == 1 || pers < 0) {
if (not)
qual_flags1[n] &= ~bitflag;
else
qual_flags1[n] |= bitflag;
}
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
if (pers == 2 || pers < 0) {
if (not)
qual_flags2[n] &= ~bitflag;
else
qual_flags2[n] |= bitflag;
}
#endif /* SUPPORTED_PERSONALITIES >= 3 */
}
static int
qual_syscall(const char *s, int bitflag, int not)
{
int i;
int rc = -1;
if (isdigit((unsigned char)*s)) {
int i = atoi(s);
if (i < 0 || i >= MAX_QUALS)
return -1;
qualify_one(i, bitflag, not, -1);
return 0;
}
for (i = 0; i < nsyscalls0; i++)
if (strcmp(s, sysent0[i].sys_name) == 0) {
qualify_one(i, bitflag, not, 0);
rc = 0;
}
#if SUPPORTED_PERSONALITIES >= 2
for (i = 0; i < nsyscalls1; i++)
if (strcmp(s, sysent1[i].sys_name) == 0) {
qualify_one(i, bitflag, not, 1);
rc = 0;
}
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
for (i = 0; i < nsyscalls2; i++)
if (strcmp(s, sysent2[i].sys_name) == 0) {
qualify_one(i, bitflag, not, 2);
rc = 0;
}
#endif /* SUPPORTED_PERSONALITIES >= 3 */
return rc;
}
static int
qual_signal(const char *s, int bitflag, int not)
{
int i;
char buf[32];
if (isdigit((unsigned char)*s)) {
int signo = atoi(s);
if (signo < 0 || signo >= MAX_QUALS)
return -1;
qualify_one(signo, bitflag, not, -1);
return 0;
}
if (strlen(s) >= sizeof buf)
return -1;
strcpy(buf, s);
s = buf;
if (strncasecmp(s, "SIG", 3) == 0)
s += 3;
for (i = 0; i <= NSIG; i++)
if (strcasecmp(s, signame(i) + 3) == 0) {
qualify_one(i, bitflag, not, -1);
return 0;
}
return -1;
}
static int
qual_fault(const char *s, int bitflag, int not)
{
return -1;
}
static int
qual_desc(const char *s, int bitflag, int not)
{
if (isdigit((unsigned char)*s)) {
int desc = atoi(s);
if (desc < 0 || desc >= MAX_QUALS)
return -1;
qualify_one(desc, bitflag, not, -1);
return 0;
}
return -1;
}
static int
lookup_class(const char *s)
{
if (strcmp(s, "file") == 0)
return TRACE_FILE;
if (strcmp(s, "ipc") == 0)
return TRACE_IPC;
if (strcmp(s, "network") == 0)
return TRACE_NETWORK;
if (strcmp(s, "process") == 0)
return TRACE_PROCESS;
if (strcmp(s, "signal") == 0)
return TRACE_SIGNAL;
if (strcmp(s, "desc") == 0)
return TRACE_DESC;
return -1;
}
void
qualify(const char *s)
{
const struct qual_options *opt;
int not;
char *copy;
const char *p;
int i, n;
opt = &qual_options[0];
for (i = 0; (p = qual_options[i].option_name); i++) {
n = strlen(p);
if (strncmp(s, p, n) == 0 && s[n] == '=') {
opt = &qual_options[i];
s += n + 1;
break;
}
}
not = 0;
if (*s == '!') {
not = 1;
s++;
}
if (strcmp(s, "none") == 0) {
not = 1 - not;
s = "all";
}
if (strcmp(s, "all") == 0) {
for (i = 0; i < MAX_QUALS; i++) {
qualify_one(i, opt->bitflag, not, -1);
}
return;
}
for (i = 0; i < MAX_QUALS; i++) {
qualify_one(i, opt->bitflag, !not, -1);
}
copy = strdup(s);
if (!copy)
die_out_of_memory();
for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
for (i = 0; i < nsyscalls0; i++)
if (sysent0[i].sys_flags & n)
qualify_one(i, opt->bitflag, not, 0);
#if SUPPORTED_PERSONALITIES >= 2
for (i = 0; i < nsyscalls1; i++)
if (sysent1[i].sys_flags & n)
qualify_one(i, opt->bitflag, not, 1);
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
for (i = 0; i < nsyscalls2; i++)
if (sysent2[i].sys_flags & n)
qualify_one(i, opt->bitflag, not, 2);
#endif /* SUPPORTED_PERSONALITIES >= 3 */
continue;
}
if (opt->qualify(p, opt->bitflag, not)) {
fprintf(stderr, "strace: invalid %s `%s'\n",
opt->argument_name, p);
exit(1);
}
}
free(copy);
return;
}
#ifndef FREEBSD
enum subcall_style { shift_style, deref_style, mask_style, door_style };
#else /* FREEBSD */
enum subcall_style { shift_style, deref_style, mask_style, door_style, table_style };
struct subcall {
int call;
int nsubcalls;
int subcalls[5];
};
static const struct subcall subcalls_table[] = {
{ SYS_shmsys, 5, { SYS_shmat, SYS_shmctl, SYS_shmdt, SYS_shmget, SYS_shmctl } },
#ifdef SYS_semconfig
{ SYS_semsys, 4, { SYS___semctl, SYS_semget, SYS_semop, SYS_semconfig } },
#else
{ SYS_semsys, 3, { SYS___semctl, SYS_semget, SYS_semop } },
#endif
{ SYS_msgsys, 4, { SYS_msgctl, SYS_msgget, SYS_msgsnd, SYS_msgrcv } },
};
#endif /* FREEBSD */
#if !(defined(LINUX) && ( defined(ALPHA) || defined(MIPS) || defined(__ARM_EABI__) ))
static void
decode_subcall(struct tcb *tcp, int subcall, int nsubcalls, enum subcall_style style)
{
unsigned long addr, mask;
int i, n;
int size = personality_wordsize[current_personality];
switch (style) {
case shift_style:
if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= nsubcalls)
return;
tcp->scno = subcall + tcp->u_arg[0];
tcp->u_nargs = n = sysent[tcp->scno].nargs;
for (i = 0; i < n; i++)
tcp->u_arg[i] = tcp->u_arg[i + 1];
break;
case deref_style:
if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= nsubcalls)
return;
tcp->scno = subcall + tcp->u_arg[0];
addr = tcp->u_arg[1];
tcp->u_nargs = n = sysent[tcp->scno].nargs;
for (i = 0; i < n; i++) {
if (size == sizeof(int)) {
unsigned int arg;
if (umove(tcp, addr, &arg) < 0)
arg = 0;
tcp->u_arg[i] = arg;
}
else if (size == sizeof(long)) {
unsigned long arg;
if (umove(tcp, addr, &arg) < 0)
arg = 0;
tcp->u_arg[i] = arg;
}
else
abort();
addr += size;
}
break;
case mask_style:
mask = (tcp->u_arg[0] >> 8) & 0xff;
for (i = 0; mask; i++)
mask >>= 1;
if (i >= nsubcalls)
return;
tcp->u_arg[0] &= 0xff;
tcp->scno = subcall + i;
tcp->u_nargs = sysent[tcp->scno].nargs;
break;
case door_style:
/*
* Oh, yuck. The call code is the *sixth* argument.
* (don't you mean the *last* argument? - JH)
*/
if (tcp->u_arg[5] < 0 || tcp->u_arg[5] >= nsubcalls)
return;
tcp->scno = subcall + tcp->u_arg[5];
tcp->u_nargs = sysent[tcp->scno].nargs;
break;
#ifdef FREEBSD
case table_style:
for (i = 0; i < ARRAY_SIZE(subcalls_table); i++)
if (subcalls_table[i].call == tcp->scno) break;
if (i < ARRAY_SIZE(subcalls_table) &&
tcp->u_arg[0] >= 0 && tcp->u_arg[0] < subcalls_table[i].nsubcalls) {
tcp->scno = subcalls_table[i].subcalls[tcp->u_arg[0]];
for (i = 0; i < tcp->u_nargs; i++)
tcp->u_arg[i] = tcp->u_arg[i + 1];
}
break;
#endif /* FREEBSD */
}
}
#endif
int
printargs(struct tcb *tcp)
{
if (entering(tcp)) {
int i;
for (i = 0; i < tcp->u_nargs; i++)
tprintf("%s%#lx", i ? ", " : "", tcp->u_arg[i]);
}
return 0;
}
long
getrval2(struct tcb *tcp)
{
long val = -1;
#ifdef LINUX
#if defined (SPARC) || defined (SPARC64)
struct pt_regs regs;
if (ptrace(PTRACE_GETREGS, tcp->pid, (char *)&regs, 0) < 0)
return -1;
val = regs.u_regs[U_REG_O1];
#elif defined(SH)
if (upeek(tcp, 4*(REG_REG0+1), &val) < 0)
return -1;
#elif defined(IA64)
if (upeek(tcp, PT_R9, &val) < 0)
return -1;
#endif
#endif /* LINUX */
#ifdef SUNOS4
if (upeek(tcp, uoff(u_rval2), &val) < 0)
return -1;
#endif /* SUNOS4 */
#ifdef SVR4
#ifdef SPARC
val = tcp->status.PR_REG[R_O1];
#endif /* SPARC */
#ifdef I386
val = tcp->status.PR_REG[EDX];
#endif /* I386 */
#ifdef X86_64
val = tcp->status.PR_REG[RDX];
#endif /* X86_64 */
#ifdef MIPS
val = tcp->status.PR_REG[CTX_V1];
#endif /* MIPS */
#endif /* SVR4 */
#ifdef FREEBSD
struct reg regs;
pread(tcp->pfd_reg, &regs, sizeof(regs), 0);
val = regs.r_edx;
#endif
return val;
}
#ifdef SUNOS4
/*
* Apparently, indirect system calls have already be converted by ptrace(2),
* so if you see "indir" this program has gone astray.
*/
int
sys_indir(struct tcb *tcp)
{
int i, nargs;
long scno;
if (entering(tcp)) {
scno = tcp->u_arg[0];
if (!SCNO_IN_RANGE(scno)) {
fprintf(stderr, "Bogus syscall: %ld\n", scno);
return 0;
}
nargs = sysent[scno].nargs;
tprints(sysent[scno].sys_name);
for (i = 0; i < nargs; i++)
tprintf(", %#lx", tcp->u_arg[i+1]);
}
return 0;
}
#endif /* SUNOS4 */
int
is_restart_error(struct tcb *tcp)
{
#ifdef LINUX
if (!syserror(tcp))
return 0;
switch (tcp->u_error) {
case ERESTARTSYS:
case ERESTARTNOINTR:
case ERESTARTNOHAND:
case ERESTART_RESTARTBLOCK:
return 1;
default:
break;
}
#endif /* LINUX */
return 0;
}
struct tcb *tcp_last = NULL;
#ifdef LINUX
# if defined(I386)
struct pt_regs i386_regs;
# elif defined(X86_64)
struct pt_regs x86_64_regs;
# elif defined (IA64)
long r8, r10, psr; /* TODO: make static? */
long ia32 = 0; /* not static */
# elif defined (POWERPC)
static long result;
# elif defined (M68K)
static long d0;
# elif defined(BFIN)
static long r0;
# elif defined (ARM)
static struct pt_regs regs;
# elif defined (ALPHA)
static long r0;
static long a3;
# elif defined(AVR32)
static struct pt_regs regs;
# elif defined (SPARC) || defined (SPARC64)
static struct pt_regs regs;
static unsigned long trap;
# elif defined(LINUX_MIPSN32)
static long long a3;
static long long r2;
# elif defined(MIPS)
static long a3;
static long r2;
# elif defined(S390) || defined(S390X)
static long gpr2;
static long pc;
static long syscall_mode;
# elif defined(HPPA)
static long r28;
# elif defined(SH)
static long r0;
# elif defined(SH64)
static long r9;
# elif defined(CRISV10) || defined(CRISV32)
static long r10;
# elif defined(MICROBLAZE)
static long r3;
# endif
#endif /* LINUX */
#ifdef FREEBSD
struct reg regs; /* TODO: make static? */
#endif /* FREEBSD */
/* Returns:
* 0: "ignore this ptrace stop", bail out of trace_syscall() silently.
* 1: ok, continue in trace_syscall().
* other: error, trace_syscall() should print error indicator
* ("????" etc) and bail out.
*/
#ifndef USE_PROCFS
static
#endif
int
get_scno(struct tcb *tcp)
{
long scno = 0;
#ifdef LINUX
# if defined(S390) || defined(S390X)
if (upeek(tcp, PT_GPR2, &syscall_mode) < 0)
return -1;
if (syscall_mode != -ENOSYS) {
/*
* Since kernel version 2.5.44 the scno gets passed in gpr2.
*/
scno = syscall_mode;
} else {
/*
* Old style of "passing" the scno via the SVC instruction.
*/
long opcode, offset_reg, tmp;
void *svc_addr;
static const int gpr_offset[16] = {
PT_GPR0, PT_GPR1, PT_ORIGGPR2, PT_GPR3,
PT_GPR4, PT_GPR5, PT_GPR6, PT_GPR7,
PT_GPR8, PT_GPR9, PT_GPR10, PT_GPR11,
PT_GPR12, PT_GPR13, PT_GPR14, PT_GPR15
};
if (upeek(tcp, PT_PSWADDR, &pc) < 0)
return -1;
errno = 0;
opcode = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)(pc-sizeof(long)), 0);
if (errno) {
perror("peektext(pc-oneword)");
return -1;
}
/*
* We have to check if the SVC got executed directly or via an
* EXECUTE instruction. In case of EXECUTE it is necessary to do
* instruction decoding to derive the system call number.
* Unfortunately the opcode sizes of EXECUTE and SVC are differently,
* so that this doesn't work if a SVC opcode is part of an EXECUTE
* opcode. Since there is no way to find out the opcode size this
* is the best we can do...
*/
if ((opcode & 0xff00) == 0x0a00) {
/* SVC opcode */
scno = opcode & 0xff;
}
else {
/* SVC got executed by EXECUTE instruction */
/*
* Do instruction decoding of EXECUTE. If you really want to
* understand this, read the Principles of Operations.
*/
svc_addr = (void *) (opcode & 0xfff);
tmp = 0;
offset_reg = (opcode & 0x000f0000) >> 16;
if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
return -1;
svc_addr += tmp;
tmp = 0;
offset_reg = (opcode & 0x0000f000) >> 12;
if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
return -1;
svc_addr += tmp;
scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, svc_addr, 0);
if (errno)
return -1;
# if defined(S390X)
scno >>= 48;
# else
scno >>= 16;
# endif
tmp = 0;
offset_reg = (opcode & 0x00f00000) >> 20;
if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
return -1;
scno = (scno | tmp) & 0xff;
}
}
# elif defined (POWERPC)
if (upeek(tcp, sizeof(unsigned long)*PT_R0, &scno) < 0)
return -1;
# ifdef POWERPC64
/* TODO: speed up strace by not doing this at every syscall.
* We only need to do it after execve.
*/
int currpers;
long val;
int pid = tcp->pid;
/* Check for 64/32 bit mode. */
if (upeek(tcp, sizeof(unsigned long)*PT_MSR, &val) < 0)
return -1;
/* SF is bit 0 of MSR */
if (val < 0)
currpers = 0;
else
currpers = 1;
update_personality(tcp, currpers);
# endif
# elif defined(AVR32)
/* Read complete register set in one go. */
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, &regs) < 0)
return -1;
scno = regs.r8;
# elif defined(BFIN)
if (upeek(tcp, PT_ORIG_P0, &scno))
return -1;
# elif defined (I386)
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &i386_regs) < 0)
return -1;
scno = i386_regs.orig_eax;
# elif defined (X86_64)
int currpers;
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &x86_64_regs) < 0)
return -1;
scno = x86_64_regs.orig_rax;
/* Check CS register value. On x86-64 linux it is:
* 0x33 for long mode (64 bit)
* 0x23 for compatibility mode (32 bit)
*/
switch (x86_64_regs.cs) {
case 0x23: currpers = 1; break;
case 0x33: currpers = 0; break;
default:
fprintf(stderr, "Unknown value CS=0x%08X while "
"detecting personality of process "
"PID=%d\n", (int)x86_64_regs.cs, tcp->pid);
currpers = current_personality;
break;
}
# if 0
/* This version analyzes the opcode of a syscall instruction.
* (int 0x80 on i386 vs. syscall on x86-64)
* It works, but is too complicated.
*/
unsigned long val, rip, i;
rip = x86_64_regs.rip;
/* sizeof(syscall) == sizeof(int 0x80) == 2 */
rip -= 2;
errno = 0;
call = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)rip, (char *)0);
if (errno)
fprintf(stderr, "ptrace_peektext failed: %s\n",
strerror(errno));
switch (call & 0xffff) {
/* x86-64: syscall = 0x0f 0x05 */
case 0x050f: currpers = 0; break;
/* i386: int 0x80 = 0xcd 0x80 */
case 0x80cd: currpers = 1; break;
default:
currpers = current_personality;
fprintf(stderr,
"Unknown syscall opcode (0x%04X) while "
"detecting personality of process "
"PID=%d\n", (int)call, tcp->pid);
break;
}
# endif
update_personality(tcp, currpers);
# elif defined(IA64)
# define IA64_PSR_IS ((long)1 << 34)
if (upeek(tcp, PT_CR_IPSR, &psr) >= 0)
ia32 = (psr & IA64_PSR_IS) != 0;
if (ia32) {
if (upeek(tcp, PT_R1, &scno) < 0)
return -1;
} else {
if (upeek(tcp, PT_R15, &scno) < 0)
return -1;
}
# elif defined (ARM)
/* Read complete register set in one go. */
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (void *)&regs) == -1)
return -1;
/*
* We only need to grab the syscall number on syscall entry.
*/
if (regs.ARM_ip == 0) {
/*
* Note: we only deal with only 32-bit CPUs here.
*/
if (regs.ARM_cpsr & 0x20) {
/*
* Get the Thumb-mode system call number
*/
scno = regs.ARM_r7;
} else {
/*
* Get the ARM-mode system call number
*/
errno = 0;
scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, (void *)(regs.ARM_pc - 4), NULL);
if (errno)
return -1;
/* Handle the EABI syscall convention. We do not
bother converting structures between the two
ABIs, but basic functionality should work even
if strace and the traced program have different
ABIs. */
if (scno == 0xef000000) {
scno = regs.ARM_r7;
} else {
if ((scno & 0x0ff00000) != 0x0f900000) {
fprintf(stderr, "syscall: unknown syscall trap 0x%08lx\n",
scno);
return -1;
}
/*
* Fixup the syscall number
*/
scno &= 0x000fffff;
}
}
if (scno & 0x0f0000) {
/*
* Handle ARM specific syscall
*/
update_personality(tcp, 1);
scno &= 0x0000ffff;
} else
update_personality(tcp, 0);
} else {
fprintf(stderr, "pid %d stray syscall entry\n", tcp->pid);
tcp->flags |= TCB_INSYSCALL;
}
# elif defined (M68K)
if (upeek(tcp, 4*PT_ORIG_D0, &scno) < 0)
return -1;
# elif defined (LINUX_MIPSN32)
unsigned long long regs[38];
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
return -1;
a3 = regs[REG_A3];
r2 = regs[REG_V0];
scno = r2;
if (!SCNO_IN_RANGE(scno)) {
if (a3 == 0 || a3 == -1) {
if (debug)
fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
return 0;
}
}
# elif defined (MIPS)
if (upeek(tcp, REG_A3, &a3) < 0)
return -1;
if (upeek(tcp, REG_V0, &scno) < 0)
return -1;
if (!SCNO_IN_RANGE(scno)) {
if (a3 == 0 || a3 == -1) {
if (debug)
fprintf(stderr, "stray syscall exit: v0 = %ld\n", scno);
return 0;
}
}
# elif defined (ALPHA)
if (upeek(tcp, REG_A3, &a3) < 0)
return -1;
if (upeek(tcp, REG_R0, &scno) < 0)
return -1;
/*
* Do some sanity checks to figure out if it's
* really a syscall entry
*/
if (!SCNO_IN_RANGE(scno)) {
if (a3 == 0 || a3 == -1) {
if (debug)
fprintf(stderr, "stray syscall exit: r0 = %ld\n", scno);
return 0;
}
}
# elif defined (SPARC) || defined (SPARC64)
/* Everything we need is in the current register set. */
if (ptrace(PTRACE_GETREGS, tcp->pid, (char *)&regs, 0) < 0)
return -1;
/* Disassemble the syscall trap. */
/* Retrieve the syscall trap instruction. */
errno = 0;
# if defined(SPARC64)
trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)regs.tpc, 0);
trap >>= 32;
# else
trap = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)regs.pc, 0);
# endif
if (errno)
return -1;
/* Disassemble the trap to see what personality to use. */
switch (trap) {
case 0x91d02010:
/* Linux/SPARC syscall trap. */
update_personality(tcp, 0);
break;
case 0x91d0206d:
/* Linux/SPARC64 syscall trap. */
update_personality(tcp, 2);
break;
case 0x91d02000:
/* SunOS syscall trap. (pers 1) */
fprintf(stderr, "syscall: SunOS no support\n");
return -1;
case 0x91d02008:
/* Solaris 2.x syscall trap. (per 2) */
update_personality(tcp, 1);
break;
case 0x91d02009:
/* NetBSD/FreeBSD syscall trap. */
fprintf(stderr, "syscall: NetBSD/FreeBSD not supported\n");
return -1;
case 0x91d02027:
/* Solaris 2.x gettimeofday */
update_personality(tcp, 1);
break;
default:
# if defined (SPARC64)
fprintf(stderr, "syscall: unknown syscall trap %08lx %016lx\n", trap, regs.tpc);
# else
fprintf(stderr, "syscall: unknown syscall trap %08lx %08lx\n", trap, regs.pc);
# endif
return -1;
}
/* Extract the system call number from the registers. */
if (trap == 0x91d02027)
scno = 156;
else
scno = regs.u_regs[U_REG_G1];
if (scno == 0) {
scno = regs.u_regs[U_REG_O0];
memmove(&regs.u_regs[U_REG_O0], &regs.u_regs[U_REG_O1], 7*sizeof(regs.u_regs[0]));
}
# elif defined(HPPA)
if (upeek(tcp, PT_GR20, &scno) < 0)
return -1;
# elif defined(SH)
/*
* In the new syscall ABI, the system call number is in R3.
*/
if (upeek(tcp, 4*(REG_REG0+3), &scno) < 0)
return -1;
if (scno < 0) {
/* Odd as it may seem, a glibc bug has been known to cause
glibc to issue bogus negative syscall numbers. So for
our purposes, make strace print what it *should* have been */
long correct_scno = (scno & 0xff);
if (debug)
fprintf(stderr,
"Detected glibc bug: bogus system call"
" number = %ld, correcting to %ld\n",
scno,
correct_scno);
scno = correct_scno;
}
# elif defined(SH64)
if (upeek(tcp, REG_SYSCALL, &scno) < 0)
return -1;
scno &= 0xFFFF;
# elif defined(CRISV10) || defined(CRISV32)
if (upeek(tcp, 4*PT_R9, &scno) < 0)
return -1;
# elif defined(TILE)
if (upeek(tcp, PTREGS_OFFSET_REG(10), &scno) < 0)
return -1;
# elif defined(MICROBLAZE)
if (upeek(tcp, 0, &scno) < 0)
return -1;
# endif
#endif /* LINUX */
#ifdef SUNOS4
if (upeek(tcp, uoff(u_arg[7]), &scno) < 0)
return -1;
#elif defined(SH)
/* new syscall ABI returns result in R0 */
if (upeek(tcp, 4*REG_REG0, (long *)&r0) < 0)
return -1;
#elif defined(SH64)
/* ABI defines result returned in r9 */
if (upeek(tcp, REG_GENERAL(9), (long *)&r9) < 0)
return -1;
#endif
#ifdef USE_PROCFS
# ifdef HAVE_PR_SYSCALL
scno = tcp->status.PR_SYSCALL;
# else
# ifndef FREEBSD
scno = tcp->status.PR_WHAT;
# else
if (pread(tcp->pfd_reg, &regs, sizeof(regs), 0) < 0) {
perror("pread");
return -1;
}
switch (regs.r_eax) {
case SYS_syscall:
case SYS___syscall:
pread(tcp->pfd, &scno, sizeof(scno), regs.r_esp + sizeof(int));
break;
default:
scno = regs.r_eax;
break;
}
# endif /* FREEBSD */
# endif /* !HAVE_PR_SYSCALL */
#endif /* USE_PROCFS */
tcp->scno = scno;
return 1;
}
long
known_scno(struct tcb *tcp)
{
long scno = tcp->scno;
#if SUPPORTED_PERSONALITIES > 1
if (SCNO_IN_RANGE(scno) && sysent[scno].native_scno != 0)
scno = sysent[scno].native_scno;
else
#endif
scno += NR_SYSCALL_BASE;
return scno;
}
/* Called at each syscall entry.
* Returns:
* 0: "ignore this ptrace stop", bail out of trace_syscall() silently.
* 1: ok, continue in trace_syscall().
* other: error, trace_syscall() should print error indicator
* ("????" etc) and bail out.
*/
static int
syscall_fixup_on_sysenter(struct tcb *tcp)
{
#ifdef USE_PROCFS
int scno = known_scno(tcp);
if (tcp->status.PR_WHY != PR_SYSENTRY) {
if (
scno == SYS_fork
#ifdef SYS_vfork
|| scno == SYS_vfork
#endif
#ifdef SYS_fork1
|| scno == SYS_fork1
#endif
#ifdef SYS_forkall
|| scno == SYS_forkall
#endif
#ifdef SYS_rfork1
|| scno == SYS_rfork1
#endif
#ifdef SYS_rforkall
|| scno == SYS_rforkall
#endif
) {
/* We are returning in the child, fake it. */
tcp->status.PR_WHY = PR_SYSENTRY;
trace_syscall(tcp);
tcp->status.PR_WHY = PR_SYSEXIT;
}
else {
fprintf(stderr, "syscall: missing entry\n");
tcp->flags |= TCB_INSYSCALL;
}
}
#endif /* USE_PROCFS */
#ifdef SUNOS4
if (scno == 0) {
fprintf(stderr, "syscall: missing entry\n");
tcp->flags |= TCB_INSYSCALL;
}
#endif
#ifdef LINUX
/* A common case of "not a syscall entry" is post-execve SIGTRAP */
#if defined (I386)
if (i386_regs.eax != -ENOSYS) {
if (debug)
fprintf(stderr, "not a syscall entry (eax = %ld)\n", i386_regs.eax);
return 0;
}
#elif defined (X86_64)
{
long rax = x86_64_regs.rax;
if (current_personality == 1)
rax = (int)rax; /* sign extend from 32 bits */
if (rax != -ENOSYS) {
if (debug)
fprintf(stderr, "not a syscall entry (rax = %ld)\n", rax);
return 0;
}
}
#elif defined (S390) || defined (S390X)
/* TODO: we already fetched PT_GPR2 in get_scno
* and stored it in syscall_mode, reuse it here
* instead of re-fetching?
*/
if (upeek(tcp, PT_GPR2, &gpr2) < 0)
return -1;
if (syscall_mode != -ENOSYS)
syscall_mode = tcp->scno;
if (gpr2 != syscall_mode) {
if (debug)
fprintf(stderr, "not a syscall entry (gpr2 = %ld)\n", gpr2);
return 0;
}
#elif defined (M68K)
/* TODO? Eliminate upeek's in arches below like we did in x86 */
if (upeek(tcp, 4*PT_D0, &d0) < 0)
return -1;
if (d0 != -ENOSYS) {
if (debug)
fprintf(stderr, "not a syscall entry (d0 = %ld)\n", d0);
return 0;
}
#elif defined(IA64)
if (upeek(tcp, PT_R10, &r10) < 0)
return -1;
if (upeek(tcp, PT_R8, &r8) < 0)
return -1;
if (ia32 && r8 != -ENOSYS) {
if (debug)
fprintf(stderr, "not a syscall entry (r8 = %ld)\n", r8);
return 0;
}
#elif defined(CRISV10) || defined(CRISV32)
if (upeek(tcp, 4*PT_R10, &r10) < 0)
return -1;
if (r10 != -ENOSYS) {
if (debug)
fprintf(stderr, "not a syscall entry (r10 = %ld)\n", r10);
return 0;
}
#elif defined(MICROBLAZE)
if (upeek(tcp, 3 * 4, &r3) < 0)
return -1;
if (r3 != -ENOSYS) {
if (debug)
fprintf(stderr, "not a syscall entry (r3 = %ld)\n", r3);
return 0;
}
#endif
#endif /* LINUX */
return 1;
}
static int
internal_syscall(struct tcb *tcp)
{
/*
* We must always trace a few critical system calls in order to
* correctly support following forks in the presence of tracing
* qualifiers.
*/
int (*func)();
if (!SCNO_IN_RANGE(tcp->scno))
return 0;
func = sysent[tcp->scno].sys_func;
if ( sys_fork == func
#if defined(FREEBSD) || defined(LINUX) || defined(SUNOS4)
|| sys_vfork == func
#endif
#ifdef LINUX
|| sys_clone == func
#endif
#if UNIXWARE > 2
|| sys_rfork == func
#endif
)
return internal_fork(tcp);
#if defined SUNOS4 || (defined LINUX && defined TCB_WAITEXECVE)
if ( sys_execve == func
# if defined(SPARC) || defined(SPARC64) || defined(SUNOS4)
|| sys_execv == func
# endif
# if UNIXWARE > 2
|| sys_rexecve == func
# endif
)
return internal_exec(tcp);
#endif
return 0;
}
static int
syscall_enter(struct tcb *tcp)
{
#ifdef LINUX
int i, nargs;
if (SCNO_IN_RANGE(tcp->scno))
nargs = tcp->u_nargs = sysent[tcp->scno].nargs;
else
nargs = tcp->u_nargs = MAX_ARGS;
# if defined(S390) || defined(S390X)
for (i = 0; i < nargs; ++i)
if (upeek(tcp, i==0 ? PT_ORIGGPR2 : PT_GPR2 + i*sizeof(long), &tcp->u_arg[i]) < 0)
return -1;
# elif defined(ALPHA)
for (i = 0; i < nargs; ++i)
if (upeek(tcp, REG_A0+i, &tcp->u_arg[i]) < 0)
return -1;
# elif defined(IA64)
if (!ia32) {
unsigned long *out0, cfm, sof, sol;
long rbs_end;
/* be backwards compatible with kernel < 2.4.4... */
# ifndef PT_RBS_END
# define PT_RBS_END PT_AR_BSP
# endif
if (upeek(tcp, PT_RBS_END, &rbs_end) < 0)
return -1;
if (upeek(tcp, PT_CFM, (long *) &cfm) < 0)
return -1;
sof = (cfm >> 0) & 0x7f;
sol = (cfm >> 7) & 0x7f;
out0 = ia64_rse_skip_regs((unsigned long *) rbs_end, -sof + sol);
for (i = 0; i < nargs; ++i) {
if (umoven(tcp, (unsigned long) ia64_rse_skip_regs(out0, i),
sizeof(long), (char *) &tcp->u_arg[i]) < 0)
return -1;
}
} else {
static const int argreg[MAX_ARGS] = { PT_R11 /* EBX = out0 */,
PT_R9 /* ECX = out1 */,
PT_R10 /* EDX = out2 */,
PT_R14 /* ESI = out3 */,
PT_R15 /* EDI = out4 */,
PT_R13 /* EBP = out5 */};
for (i = 0; i < nargs; ++i) {
if (upeek(tcp, argreg[i], &tcp->u_arg[i]) < 0)
return -1;
/* truncate away IVE sign-extension */
tcp->u_arg[i] &= 0xffffffff;
}
}
# elif defined(LINUX_MIPSN32) || defined(LINUX_MIPSN64)
/* N32 and N64 both use up to six registers. */
unsigned long long regs[38];
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
return -1;
for (i = 0; i < nargs; ++i) {
tcp->u_arg[i] = regs[REG_A0 + i];
# if defined(LINUX_MIPSN32)
tcp->ext_arg[i] = regs[REG_A0 + i];
# endif
}
# elif defined(MIPS)
if (nargs > 4) {
long sp;
if (upeek(tcp, REG_SP, &sp) < 0)
return -1;
for (i = 0; i < 4; ++i)
if (upeek(tcp, REG_A0 + i, &tcp->u_arg[i]) < 0)
return -1;
umoven(tcp, sp + 16, (nargs - 4) * sizeof(tcp->u_arg[0]),
(char *)(tcp->u_arg + 4));
} else {
for (i = 0; i < nargs; ++i)
if (upeek(tcp, REG_A0 + i, &tcp->u_arg[i]) < 0)
return -1;
}
# elif defined(POWERPC)
# ifndef PT_ORIG_R3
# define PT_ORIG_R3 34
# endif
for (i = 0; i < nargs; ++i) {
if (upeek(tcp, (i==0) ?
(sizeof(unsigned long) * PT_ORIG_R3) :
((i+PT_R3) * sizeof(unsigned long)),
&tcp->u_arg[i]) < 0)
return -1;
}
# elif defined(SPARC) || defined(SPARC64)
for (i = 0; i < nargs; ++i)
tcp->u_arg[i] = regs.u_regs[U_REG_O0 + i];
# elif defined(HPPA)
for (i = 0; i < nargs; ++i)
if (upeek(tcp, PT_GR26-4*i, &tcp->u_arg[i]) < 0)
return -1;
# elif defined(ARM)
for (i = 0; i < nargs; ++i)
tcp->u_arg[i] = regs.uregs[i];
# elif defined(AVR32)
(void)i;
(void)nargs;
tcp->u_arg[0] = regs.r12;
tcp->u_arg[1] = regs.r11;
tcp->u_arg[2] = regs.r10;
tcp->u_arg[3] = regs.r9;
tcp->u_arg[4] = regs.r5;
tcp->u_arg[5] = regs.r3;
# elif defined(BFIN)
static const int argreg[MAX_ARGS] = { PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5 };
for (i = 0; i < nargs; ++i)
if (upeek(tcp, argreg[i], &tcp->u_arg[i]) < 0)
return -1;
# elif defined(SH)
static const int syscall_regs[MAX_ARGS] = {
4 * (REG_REG0+4), 4 * (REG_REG0+5), 4 * (REG_REG0+6),
4 * (REG_REG0+7), 4 * (REG_REG0 ), 4 * (REG_REG0+1)
};
for (i = 0; i < nargs; ++i)
if (upeek(tcp, syscall_regs[i], &tcp->u_arg[i]) < 0)
return -1;
# elif defined(SH64)
int i;
/* Registers used by SH5 Linux system calls for parameters */
static const int syscall_regs[MAX_ARGS] = { 2, 3, 4, 5, 6, 7 };
for (i = 0; i < nargs; ++i)
if (upeek(tcp, REG_GENERAL(syscall_regs[i]), &tcp->u_arg[i]) < 0)
return -1;
# elif defined(X86_64)
(void)i;
(void)nargs;
if (current_personality == 0) { /* x86-64 ABI */
tcp->u_arg[0] = x86_64_regs.rdi;
tcp->u_arg[1] = x86_64_regs.rsi;
tcp->u_arg[2] = x86_64_regs.rdx;
tcp->u_arg[3] = x86_64_regs.r10;
tcp->u_arg[4] = x86_64_regs.r8;
tcp->u_arg[5] = x86_64_regs.r9;
} else { /* i386 ABI */
/* Sign-extend lower 32 bits */
tcp->u_arg[0] = (long)(int)x86_64_regs.rbx;
tcp->u_arg[1] = (long)(int)x86_64_regs.rcx;
tcp->u_arg[2] = (long)(int)x86_64_regs.rdx;
tcp->u_arg[3] = (long)(int)x86_64_regs.rsi;
tcp->u_arg[4] = (long)(int)x86_64_regs.rdi;
tcp->u_arg[5] = (long)(int)x86_64_regs.rbp;
}
# elif defined(MICROBLAZE)
for (i = 0; i < nargs; ++i)
if (upeek(tcp, (5 + i) * 4, &tcp->u_arg[i]) < 0)
return -1;
# elif defined(CRISV10) || defined(CRISV32)
static const int crisregs[MAX_ARGS] = {
4*PT_ORIG_R10, 4*PT_R11, 4*PT_R12,
4*PT_R13 , 4*PT_MOF, 4*PT_SRP
};
for (i = 0; i < nargs; ++i)
if (upeek(tcp, crisregs[i], &tcp->u_arg[i]) < 0)
return -1;
# elif defined(TILE)
for (i = 0; i < nargs; ++i)
if (upeek(tcp, PTREGS_OFFSET_REG(i), &tcp->u_arg[i]) < 0)
return -1;
# elif defined(M68K)
for (i = 0; i < nargs; ++i)
if (upeek(tcp, (i < 5 ? i : i + 2)*4, &tcp->u_arg[i]) < 0)
return -1;
# elif defined(I386)
(void)i;
(void)nargs;
tcp->u_arg[0] = i386_regs.ebx;
tcp->u_arg[1] = i386_regs.ecx;
tcp->u_arg[2] = i386_regs.edx;
tcp->u_arg[3] = i386_regs.esi;
tcp->u_arg[4] = i386_regs.edi;
tcp->u_arg[5] = i386_regs.ebp;
# else /* Other architecture (32bits specific) */
for (i = 0; i < nargs; ++i)
if (upeek(tcp, i*4, &tcp->u_arg[i]) < 0)
return -1;
# endif
#endif /* LINUX */
#ifdef SUNOS4
int i, nargs;
if (SCNO_IN_RANGE(tcp->scno))
nargs = tcp->u_nargs = sysent[tcp->scno].nargs;
else
nargs = tcp->u_nargs = MAX_ARGS;
for (i = 0; i < nargs; i++) {
struct user *u;
if (upeek(tcp, uoff(u_arg[0]) +
(i * sizeof(u->u_arg[0])), &tcp->u_arg[i]) < 0)
return -1;
}
#endif /* SUNOS4 */
#ifdef SVR4
# ifdef MIPS
/*
* SGI is broken: even though it has pr_sysarg, it doesn't
* set them on system call entry. Get a clue.
*/
if (SCNO_IN_RANGE(tcp->scno))
tcp->u_nargs = sysent[tcp->scno].nargs;
else
tcp->u_nargs = tcp->status.pr_nsysarg;
if (tcp->u_nargs > 4) {
memcpy(tcp->u_arg, &tcp->status.pr_reg[CTX_A0],
4 * sizeof(tcp->u_arg[0]));
umoven(tcp, tcp->status.pr_reg[CTX_SP] + 16,
(tcp->u_nargs - 4) * sizeof(tcp->u_arg[0]), (char *) (tcp->u_arg + 4));
}
else {
memcpy(tcp->u_arg, &tcp->status.pr_reg[CTX_A0],
tcp->u_nargs * sizeof(tcp->u_arg[0]));
}
# elif UNIXWARE >= 2
/*
* Like SGI, UnixWare doesn't set pr_sysarg until system call exit
*/
if (SCNO_IN_RANGE(tcp->scno))
tcp->u_nargs = sysent[tcp->scno].nargs;
else
tcp->u_nargs = tcp->status.pr_lwp.pr_nsysarg;
umoven(tcp, tcp->status.PR_REG[UESP] + 4,
tcp->u_nargs * sizeof(tcp->u_arg[0]), (char *) tcp->u_arg);
# elif defined(HAVE_PR_SYSCALL)
int i;
if (SCNO_IN_RANGE(tcp->scno))
tcp->u_nargs = sysent[tcp->scno].nargs;
else
tcp->u_nargs = tcp->status.pr_nsysarg;
for (i = 0; i < tcp->u_nargs; i++)
tcp->u_arg[i] = tcp->status.pr_sysarg[i];
# elif defined(I386)
if (SCNO_IN_RANGE(tcp->scno))
tcp->u_nargs = sysent[tcp->scno].nargs;
else
tcp->u_nargs = 5;
if (tcp->u_nargs > 0)
umoven(tcp, tcp->status.PR_REG[UESP] + 4,
tcp->u_nargs * sizeof(tcp->u_arg[0]), (char *) tcp->u_arg);
# else
I DONT KNOW WHAT TO DO
# endif
#endif /* SVR4 */
#ifdef FREEBSD
if (SCNO_IN_RANGE(tcp->scno) &&
sysent[tcp->scno].nargs > tcp->status.val)
tcp->u_nargs = sysent[tcp->scno].nargs;
else
tcp->u_nargs = tcp->status.val;
if (tcp->u_nargs < 0)
tcp->u_nargs = 0;
if (tcp->u_nargs > MAX_ARGS)
tcp->u_nargs = MAX_ARGS;
switch (regs.r_eax) {
case SYS___syscall:
pread(tcp->pfd, &tcp->u_arg, tcp->u_nargs * sizeof(unsigned long),
regs.r_esp + sizeof(int) + sizeof(quad_t));
break;
case SYS_syscall:
pread(tcp->pfd, &tcp->u_arg, tcp->u_nargs * sizeof(unsigned long),
regs.r_esp + 2 * sizeof(int));
break;
default:
pread(tcp->pfd, &tcp->u_arg, tcp->u_nargs * sizeof(unsigned long),
regs.r_esp + sizeof(int));
break;
}
#endif /* FREEBSD */
return 1;
}
static int
trace_syscall_entering(struct tcb *tcp)
{
int res, scno_good;
#if defined TCB_WAITEXECVE
if (tcp->flags & TCB_WAITEXECVE) {
/* This is the post-execve SIGTRAP. */
tcp->flags &= ~TCB_WAITEXECVE;
return 0;
}
#endif
scno_good = res = get_scno(tcp);
if (res == 0)
return res;
if (res == 1)
res = syscall_fixup_on_sysenter(tcp);
if (res == 0)
return res;
if (res == 1)
res = syscall_enter(tcp);
if (res == 0)
return res;
if (res != 1) {
printleader(tcp);
tcp->flags &= ~TCB_REPRINT;
tcp_last = tcp;
if (scno_good != 1)
tprintf("????" /* anti-trigraph gap */ "(");
else if (!SCNO_IN_RANGE(tcp->scno))
tprintf("syscall_%lu(", tcp->scno);
else
tprintf("%s(", sysent[tcp->scno].sys_name);
/*
* " <unavailable>" will be added later by the code which
* detects ptrace errors.
*/
goto ret;
}
switch (known_scno(tcp)) {
#ifdef SYS_socket_subcall
case SYS_socketcall:
decode_subcall(tcp, SYS_socket_subcall,
SYS_socket_nsubcalls, deref_style);
break;
#endif
#ifdef SYS_ipc_subcall
case SYS_ipc:
decode_subcall(tcp, SYS_ipc_subcall,
SYS_ipc_nsubcalls, shift_style);
break;
#endif
#ifdef SVR4
#ifdef SYS_pgrpsys_subcall
case SYS_pgrpsys:
decode_subcall(tcp, SYS_pgrpsys_subcall,
SYS_pgrpsys_nsubcalls, shift_style);
break;
#endif /* SYS_pgrpsys_subcall */
#ifdef SYS_sigcall_subcall
case SYS_sigcall:
decode_subcall(tcp, SYS_sigcall_subcall,
SYS_sigcall_nsubcalls, mask_style);
break;
#endif /* SYS_sigcall_subcall */
case SYS_msgsys:
decode_subcall(tcp, SYS_msgsys_subcall,
SYS_msgsys_nsubcalls, shift_style);
break;
case SYS_shmsys:
decode_subcall(tcp, SYS_shmsys_subcall,
SYS_shmsys_nsubcalls, shift_style);
break;
case SYS_semsys:
decode_subcall(tcp, SYS_semsys_subcall,
SYS_semsys_nsubcalls, shift_style);
break;
case SYS_sysfs:
decode_subcall(tcp, SYS_sysfs_subcall,
SYS_sysfs_nsubcalls, shift_style);
break;
case SYS_spcall:
decode_subcall(tcp, SYS_spcall_subcall,
SYS_spcall_nsubcalls, shift_style);
break;
#ifdef SYS_context_subcall
case SYS_context:
decode_subcall(tcp, SYS_context_subcall,
SYS_context_nsubcalls, shift_style);
break;
#endif /* SYS_context_subcall */
#ifdef SYS_door_subcall
case SYS_door:
decode_subcall(tcp, SYS_door_subcall,
SYS_door_nsubcalls, door_style);
break;
#endif /* SYS_door_subcall */
#ifdef SYS_kaio_subcall
case SYS_kaio:
decode_subcall(tcp, SYS_kaio_subcall,
SYS_kaio_nsubcalls, shift_style);
break;
#endif
#endif /* SVR4 */
#ifdef FREEBSD
case SYS_msgsys:
case SYS_shmsys:
case SYS_semsys:
decode_subcall(tcp, 0, 0, table_style);
break;
#endif
#ifdef SUNOS4
case SYS_semsys:
decode_subcall(tcp, SYS_semsys_subcall,
SYS_semsys_nsubcalls, shift_style);
break;
case SYS_msgsys:
decode_subcall(tcp, SYS_msgsys_subcall,
SYS_msgsys_nsubcalls, shift_style);
break;
case SYS_shmsys:
decode_subcall(tcp, SYS_shmsys_subcall,
SYS_shmsys_nsubcalls, shift_style);
break;
#endif
}
internal_syscall(tcp);
if ((SCNO_IN_RANGE(tcp->scno) &&
!(qual_flags[tcp->scno] & QUAL_TRACE)) ||
(tracing_paths && !pathtrace_match(tcp))) {
tcp->flags |= TCB_INSYSCALL | TCB_FILTERED;
return 0;
}
tcp->flags &= ~TCB_FILTERED;
if (cflag == CFLAG_ONLY_STATS) {
res = 0;
goto ret;
}
printleader(tcp);
tcp->flags &= ~TCB_REPRINT;
tcp_last = tcp;
if (!SCNO_IN_RANGE(tcp->scno))
tprintf("syscall_%lu(", tcp->scno);
else
tprintf("%s(", sysent[tcp->scno].sys_name);
if (!SCNO_IN_RANGE(tcp->scno) ||
((qual_flags[tcp->scno] & QUAL_RAW) &&
sysent[tcp->scno].sys_func != sys_exit))
res = printargs(tcp);
else
res = (*sysent[tcp->scno].sys_func)(tcp);
if (fflush(tcp->outf) == EOF)
return -1;
ret:
tcp->flags |= TCB_INSYSCALL;
/* Measure the entrance time as late as possible to avoid errors. */
if (dtime || cflag)
gettimeofday(&tcp->etime, NULL);
return res;
}
/* Returns:
* 0: "ignore this ptrace stop", bail out of trace_syscall() silently.
* 1: ok, continue in trace_syscall().
* other: error, trace_syscall() should print error indicator
* ("????" etc) and bail out.
*/
static int
get_syscall_result(struct tcb *tcp)
{
#ifdef LINUX
# if defined(S390) || defined(S390X)
if (upeek(tcp, PT_GPR2, &gpr2) < 0)
return -1;
# elif defined (POWERPC)
# define SO_MASK 0x10000000
{
long flags;
if (upeek(tcp, sizeof(unsigned long)*PT_CCR, &flags) < 0)
return -1;
if (upeek(tcp, sizeof(unsigned long)*PT_R3, &result) < 0)
return -1;
if (flags & SO_MASK)
result = -result;
}
# elif defined(AVR32)
/* Read complete register set in one go. */
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, &regs) < 0)
return -1;
# elif defined(BFIN)
if (upeek(tcp, PT_R0, &r0) < 0)
return -1;
# elif defined (I386)
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &i386_regs) < 0)
return -1;
# elif defined (X86_64)
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &x86_64_regs) < 0)
return -1;
# elif defined(IA64)
# define IA64_PSR_IS ((long)1 << 34)
if (upeek(tcp, PT_CR_IPSR, &psr) >= 0)
ia32 = (psr & IA64_PSR_IS) != 0;
if (upeek(tcp, PT_R8, &r8) < 0)
return -1;
if (upeek(tcp, PT_R10, &r10) < 0)
return -1;
# elif defined (ARM)
/* Read complete register set in one go. */
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (void *)&regs) == -1)
return -1;
# elif defined (M68K)
if (upeek(tcp, 4*PT_D0, &d0) < 0)
return -1;
# elif defined (LINUX_MIPSN32)
unsigned long long regs[38];
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (long) &regs) < 0)
return -1;
a3 = regs[REG_A3];
r2 = regs[REG_V0];
# elif defined (MIPS)
if (upeek(tcp, REG_A3, &a3) < 0)
return -1;
if (upeek(tcp, REG_V0, &r2) < 0)
return -1;
# elif defined (ALPHA)
if (upeek(tcp, REG_A3, &a3) < 0)
return -1;
if (upeek(tcp, REG_R0, &r0) < 0)
return -1;
# elif defined (SPARC) || defined (SPARC64)
/* Everything we need is in the current register set. */
if (ptrace(PTRACE_GETREGS, tcp->pid, (char *)&regs, 0) < 0)
return -1;
# elif defined(HPPA)
if (upeek(tcp, PT_GR28, &r28) < 0)
return -1;
# elif defined(SH)
# elif defined(SH64)
# elif defined(CRISV10) || defined(CRISV32)
if (upeek(tcp, 4*PT_R10, &r10) < 0)
return -1;
# elif defined(TILE)
# elif defined(MICROBLAZE)
if (upeek(tcp, 3 * 4, &r3) < 0)
return -1;
# endif
#endif /* LINUX */
#ifdef SUNOS4
#elif defined(SH)
/* new syscall ABI returns result in R0 */
if (upeek(tcp, 4*REG_REG0, (long *)&r0) < 0)
return -1;
#elif defined(SH64)
/* ABI defines result returned in r9 */
if (upeek(tcp, REG_GENERAL(9), (long *)&r9) < 0)
return -1;
#endif
#ifdef USE_PROCFS
# ifndef HAVE_PR_SYSCALL
# ifdef FREEBSD
if (pread(tcp->pfd_reg, &regs, sizeof(regs), 0) < 0) {
perror("pread");
return -1;
}
# endif /* FREEBSD */
# endif /* !HAVE_PR_SYSCALL */
#endif /* USE_PROCFS */
return 1;
}
/* Called at each syscall exit.
* Returns:
* 0: "ignore this ptrace stop", bail out of trace_syscall() silently.
* 1: ok, continue in trace_syscall().
* other: error, trace_syscall() should print error indicator
* ("????" etc) and bail out.
*/
static int
syscall_fixup_on_sysexit(struct tcb *tcp)
{
#ifdef USE_PROCFS
if (tcp->status.PR_WHY != PR_SYSEXIT) {
fprintf(stderr, "syscall: missing exit\n");
tcp->flags &= ~TCB_INSYSCALL;
}
#endif /* USE_PROCFS */
#ifdef SUNOS4
{
int scno = known_scno(tcp);
if (scno != 0) {
if (debug) {
/*
* This happens when a signal handler
* for a signal which interrupted a
* a system call makes another system call.
*/
fprintf(stderr, "syscall: missing exit\n");
}
tcp->flags &= ~TCB_INSYSCALL;
}
}
#endif /* SUNOS4 */
#ifdef LINUX
# if defined (S390) || defined (S390X)
if (syscall_mode != -ENOSYS)
syscall_mode = tcp->scno;
if ((tcp->flags & TCB_WAITEXECVE)
&& (gpr2 == -ENOSYS || gpr2 == tcp->scno)) {
/*
* Return from execve.
* Fake a return value of zero. We leave the TCB_WAITEXECVE
* flag set for the post-execve SIGTRAP to see and reset.
*/
gpr2 = 0;
}
# endif
#endif /* LINUX */
return 1;
}
#ifdef LINUX
/*
* Check the syscall return value register value for whether it is
* a negated errno code indicating an error, or a success return value.
*/
static inline int
is_negated_errno(unsigned long int val)
{
unsigned long int max = -(long int) nerrnos;
# if SUPPORTED_PERSONALITIES > 1
if (personality_wordsize[current_personality] < sizeof(val)) {
val = (unsigned int) val;
max = (unsigned int) max;
}
# endif
return val > max;
}
#endif
static int
get_error(struct tcb *tcp)
{
int u_error = 0;
#ifdef LINUX
int check_errno = 1;
if (SCNO_IN_RANGE(tcp->scno) &&
sysent[tcp->scno].sys_flags & SYSCALL_NEVER_FAILS) {
check_errno = 0;
}
# if defined(S390) || defined(S390X)
if (check_errno && is_negated_errno(gpr2)) {
tcp->u_rval = -1;
u_error = -gpr2;
}
else {
tcp->u_rval = gpr2;
}
# elif defined(I386)
if (check_errno && is_negated_errno(i386_regs.eax)) {
tcp->u_rval = -1;
u_error = -i386_regs.eax;
}
else {
tcp->u_rval = i386_regs.eax;
}
# elif defined(X86_64)
if (check_errno && is_negated_errno(x86_64_regs.rax)) {
tcp->u_rval = -1;
u_error = -x86_64_regs.rax;
}
else {
tcp->u_rval = x86_64_regs.rax;
}
# elif defined(IA64)
if (ia32) {
int err;
err = (int)r8;
if (check_errno && is_negated_errno(err)) {
tcp->u_rval = -1;
u_error = -err;
}
else {
tcp->u_rval = err;
}
} else {
if (check_errno && r10) {
tcp->u_rval = -1;
u_error = r8;
} else {
tcp->u_rval = r8;
}
}
# elif defined(MIPS)
if (check_errno && a3) {
tcp->u_rval = -1;
u_error = r2;
} else {
tcp->u_rval = r2;
}
# elif defined(POWERPC)
if (check_errno && is_negated_errno(result)) {
tcp->u_rval = -1;
u_error = -result;
}
else {
tcp->u_rval = result;
}
# elif defined(M68K)
if (check_errno && is_negated_errno(d0)) {
tcp->u_rval = -1;
u_error = -d0;
}
else {
tcp->u_rval = d0;
}
# elif defined(ARM)
if (check_errno && is_negated_errno(regs.ARM_r0)) {
tcp->u_rval = -1;
u_error = -regs.ARM_r0;
}
else {
tcp->u_rval = regs.ARM_r0;
}
# elif defined(AVR32)
if (check_errno && regs.r12 && (unsigned) -regs.r12 < nerrnos) {
tcp->u_rval = -1;
u_error = -regs.r12;
}
else {
tcp->u_rval = regs.r12;
}
# elif defined(BFIN)
if (check_errno && is_negated_errno(r0)) {
tcp->u_rval = -1;
u_error = -r0;
} else {
tcp->u_rval = r0;
}
# elif defined(ALPHA)
if (check_errno && a3) {
tcp->u_rval = -1;
u_error = r0;
}
else {
tcp->u_rval = r0;
}
# elif defined(SPARC)
if (check_errno && regs.psr & PSR_C) {
tcp->u_rval = -1;
u_error = regs.u_regs[U_REG_O0];
}
else {
tcp->u_rval = regs.u_regs[U_REG_O0];
}
# elif defined(SPARC64)
if (check_errno && regs.tstate & 0x1100000000UL) {
tcp->u_rval = -1;
u_error = regs.u_regs[U_REG_O0];
}
else {
tcp->u_rval = regs.u_regs[U_REG_O0];
}
# elif defined(HPPA)
if (check_errno && is_negated_errno(r28)) {
tcp->u_rval = -1;
u_error = -r28;
}
else {
tcp->u_rval = r28;
}
# elif defined(SH)
if (check_errno && is_negated_errno(r0)) {
tcp->u_rval = -1;
u_error = -r0;
}
else {
tcp->u_rval = r0;
}
# elif defined(SH64)
if (check_errno && is_negated_errno(r9)) {
tcp->u_rval = -1;
u_error = -r9;
}
else {
tcp->u_rval = r9;
}
# elif defined(CRISV10) || defined(CRISV32)
if (check_errno && r10 && (unsigned) -r10 < nerrnos) {
tcp->u_rval = -1;
u_error = -r10;
}
else {
tcp->u_rval = r10;
}
# elif defined(TILE)
long rval;
if (upeek(tcp, PTREGS_OFFSET_REG(0), &rval) < 0)
return -1;
if (check_errno && rval < 0 && rval > -nerrnos) {
tcp->u_rval = -1;
u_error = -rval;
}
else {
tcp->u_rval = rval;
}
# elif defined(MICROBLAZE)
if (check_errno && is_negated_errno(r3)) {
tcp->u_rval = -1;
u_error = -r3;
}
else {
tcp->u_rval = r3;
}
# endif
#endif /* LINUX */
#ifdef SUNOS4
/* get error code from user struct */
if (upeek(tcp, uoff(u_error), &u_error) < 0)
return -1;
u_error >>= 24; /* u_error is a char */
/* get system call return value */
if (upeek(tcp, uoff(u_rval1), &tcp->u_rval) < 0)
return -1;
#endif /* SUNOS4 */
#ifdef SVR4
# ifdef SPARC
/* Judicious guessing goes a long way. */
if (tcp->status.pr_reg[R_PSR] & 0x100000) {
tcp->u_rval = -1;
u_error = tcp->status.pr_reg[R_O0];
}
else {
tcp->u_rval = tcp->status.pr_reg[R_O0];
}
# endif /* SPARC */
# ifdef I386
if (tcp->status.PR_REG[EFL] & 0x1) {
tcp->u_rval = -1;
u_error = tcp->status.PR_REG[EAX];
}
else {
tcp->u_rval = tcp->status.PR_REG[EAX];
# ifdef HAVE_LONG_LONG
tcp->u_lrval =
((unsigned long long) tcp->status.PR_REG[EDX] << 32) +
tcp->status.PR_REG[EAX];
# endif
}
# endif /* I386 */
# ifdef X86_64
if (tcp->status.PR_REG[EFLAGS] & 0x1) {
tcp->u_rval = -1;
u_error = tcp->status.PR_REG[RAX];
}
else {
tcp->u_rval = tcp->status.PR_REG[RAX];
}
# endif /* X86_64 */
# ifdef MIPS
if (tcp->status.pr_reg[CTX_A3]) {
tcp->u_rval = -1;
u_error = tcp->status.pr_reg[CTX_V0];
}
else {
tcp->u_rval = tcp->status.pr_reg[CTX_V0];
}
# endif /* MIPS */
#endif /* SVR4 */
#ifdef FREEBSD
if (regs.r_eflags & PSL_C) {
tcp->u_rval = -1;
u_error = regs.r_eax;
} else {
tcp->u_rval = regs.r_eax;
tcp->u_lrval =
((unsigned long long) regs.r_edx << 32) + regs.r_eax;
}
#endif /* FREEBSD */
tcp->u_error = u_error;
return 1;
}
static void
dumpio(struct tcb *tcp)
{
if (syserror(tcp))
return;
if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= MAX_QUALS)
return;
if (!SCNO_IN_RANGE(tcp->scno))
return;
if (sysent[tcp->scno].sys_func == printargs)
return;
if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
if (sysent[tcp->scno].sys_func == sys_read ||
sysent[tcp->scno].sys_func == sys_pread ||
sysent[tcp->scno].sys_func == sys_pread64 ||
sysent[tcp->scno].sys_func == sys_recv ||
sysent[tcp->scno].sys_func == sys_recvfrom)
dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
else if (sysent[tcp->scno].sys_func == sys_readv)
dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
return;
}
if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
if (sysent[tcp->scno].sys_func == sys_write ||
sysent[tcp->scno].sys_func == sys_pwrite ||
sysent[tcp->scno].sys_func == sys_pwrite64 ||
sysent[tcp->scno].sys_func == sys_send ||
sysent[tcp->scno].sys_func == sys_sendto)
dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
else if (sysent[tcp->scno].sys_func == sys_writev)
dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
return;
}
}
static int
trace_syscall_exiting(struct tcb *tcp)
{
int sys_res;
struct timeval tv;
int res;
long u_error;
/* Measure the exit time as early as possible to avoid errors. */
if (dtime || cflag)
gettimeofday(&tv, NULL);
#if SUPPORTED_PERSONALITIES > 1
update_personality(tcp, tcp->currpers);
#endif
res = get_syscall_result(tcp);
if (res == 0)
return res;
if (res == 1)
res = syscall_fixup_on_sysexit(tcp);
if (res == 0)
return res;
if (res == 1)
res = get_error(tcp);
if (res == 0)
return res;
if (res == 1)
internal_syscall(tcp);
if (res == 1 && filtered(tcp)) {
goto ret;
}
if (tcp->flags & TCB_REPRINT) {
printleader(tcp);
if (!SCNO_IN_RANGE(tcp->scno))
tprintf("<... syscall_%lu resumed> ", tcp->scno);
else
tprintf("<... %s resumed> ", sysent[tcp->scno].sys_name);
}
if (cflag) {
struct timeval t = tv;
count_syscall(tcp, &t);
if (cflag == CFLAG_ONLY_STATS) {
goto ret;
}
}
if (res != 1) {
tprints(") ");
tabto();
tprints("= ? <unavailable>");
printtrailer();
tcp->flags &= ~TCB_INSYSCALL;
return res;
}
if (!SCNO_IN_RANGE(tcp->scno)
|| (qual_flags[tcp->scno] & QUAL_RAW))
sys_res = printargs(tcp);
else {
/* FIXME: not_failing_only (IOW, option -z) is broken:
* failure of syscall is known only after syscall return.
* Thus we end up with something like this on, say, ENOENT:
* open("doesnt_exist", O_RDONLY <unfinished ...>
* {next syscall decode}
* whereas the intended result is that open(...) line
* is not shown at all.
*/
if (not_failing_only && tcp->u_error)
goto ret; /* ignore failed syscalls */
sys_res = (*sysent[tcp->scno].sys_func)(tcp);
}
tprints(") ");
tabto();
u_error = tcp->u_error;
if (!SCNO_IN_RANGE(tcp->scno) ||
qual_flags[tcp->scno] & QUAL_RAW) {
if (u_error)
tprintf("= -1 (errno %ld)", u_error);
else
tprintf("= %#lx", tcp->u_rval);
}
else if (!(sys_res & RVAL_NONE) && u_error) {
switch (u_error) {
#ifdef LINUX
/* Blocked signals do not interrupt any syscalls.
* In this case syscalls don't return ERESTARTfoo codes.
*
* Deadly signals set to SIG_DFL interrupt syscalls
* and kill the process regardless of which of the codes below
* is returned by the interrupted syscall.
* In some cases, kernel forces a kernel-generated deadly
* signal to be unblocked and set to SIG_DFL (and thus cause
* death) if it is blocked or SIG_IGNed: for example, SIGSEGV
* or SIGILL. (The alternative is to leave process spinning
* forever on the faulty instruction - not useful).
*
* SIG_IGNed signals and non-deadly signals set to SIG_DFL
* (for example, SIGCHLD, SIGWINCH) interrupt syscalls,
* but kernel will always restart them.
*/
case ERESTARTSYS:
/* Most common type of signal-interrupted syscall exit code.
* The system call will be restarted with the same arguments
* if SA_RESTART is set; otherwise, it will fail with EINTR.
*/
tprints("= ? ERESTARTSYS (To be restarted if SA_RESTART is set)");
break;
case ERESTARTNOINTR:
/* Rare. For example, fork() returns this if interrupted.
* SA_RESTART is ignored (assumed set): the restart is unconditional.
*/
tprints("= ? ERESTARTNOINTR (To be restarted)");
break;
case ERESTARTNOHAND:
/* pause(), rt_sigsuspend() etc use this code.
* SA_RESTART is ignored (assumed not set):
* syscall won't restart (will return EINTR instead)
* even after signal with SA_RESTART set.
* However, after SIG_IGN or SIG_DFL signal it will.
*/
tprints("= ? ERESTARTNOHAND (Interrupted by signal)");
break;
case ERESTART_RESTARTBLOCK:
/* Syscalls like nanosleep(), poll() which can't be
* restarted with their original arguments use this
* code. Kernel will execute restart_syscall() instead,
* which changes arguments before restarting syscall.
* SA_RESTART is ignored (assumed not set) similarly
* to ERESTARTNOHAND. (Kernel can't honor SA_RESTART
* since restart data is saved in "restart block"
* in task struct, and if signal handler uses a syscall
* which in turn saves another such restart block,
* old data is lost and restart becomes impossible)
*/
tprints("= ? ERESTART_RESTARTBLOCK (Interrupted by signal)");
break;
#endif /* LINUX */
default:
if (u_error < 0)
tprintf("= -1 E??? (errno %ld)", u_error);
else if (u_error < nerrnos)
tprintf("= -1 %s (%s)", errnoent[u_error],
strerror(u_error));
else
tprintf("= -1 ERRNO_%ld (%s)", u_error,
strerror(u_error));
break;
}
if ((sys_res & RVAL_STR) && tcp->auxstr)
tprintf(" (%s)", tcp->auxstr);
}
else {
if (sys_res & RVAL_NONE)
tprints("= ?");
else {
switch (sys_res & RVAL_MASK) {
case RVAL_HEX:
tprintf("= %#lx", tcp->u_rval);
break;
case RVAL_OCTAL:
tprintf("= %#lo", tcp->u_rval);
break;
case RVAL_UDECIMAL:
tprintf("= %lu", tcp->u_rval);
break;
case RVAL_DECIMAL:
tprintf("= %ld", tcp->u_rval);
break;
#ifdef HAVE_LONG_LONG
case RVAL_LHEX:
tprintf("= %#llx", tcp->u_lrval);
break;
case RVAL_LOCTAL:
tprintf("= %#llo", tcp->u_lrval);
break;
case RVAL_LUDECIMAL:
tprintf("= %llu", tcp->u_lrval);
break;
case RVAL_LDECIMAL:
tprintf("= %lld", tcp->u_lrval);
break;
#endif
default:
fprintf(stderr,
"invalid rval format\n");
break;
}
}
if ((sys_res & RVAL_STR) && tcp->auxstr)
tprintf(" (%s)", tcp->auxstr);
}
if (dtime) {
tv_sub(&tv, &tv, &tcp->etime);
tprintf(" <%ld.%06ld>",
(long) tv.tv_sec, (long) tv.tv_usec);
}
printtrailer();
dumpio(tcp);
if (fflush(tcp->outf) == EOF)
return -1;
ret:
tcp->flags &= ~TCB_INSYSCALL;
return 0;
}
int
trace_syscall(struct tcb *tcp)
{
return exiting(tcp) ?
trace_syscall_exiting(tcp) : trace_syscall_entering(tcp);
}
Reference in New Issue View Git Blame Copy Permalink