Dmitry V. Levin
7488ce9e23
The result of this check is going to be used by subsequent commits. * ptrace_syscall_info.c: New file. * ptrace_syscall_info.h: Likewise. * Makefile.am (strace_SOURCES): Add them. * strace.c: Include "ptrace_syscall_info.h". (init): Call test_ptrace_get_syscall_info.
2722 lines
65 KiB
C
2722 lines
65 KiB
C
/*
|
|
* 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) 1999-2018 The strace developers.
|
|
* All rights reserved.
|
|
*
|
|
* SPDX-License-Identifier: LGPL-2.1-or-later
|
|
*/
|
|
|
|
#include "defs.h"
|
|
#include <stdarg.h>
|
|
#include <limits.h>
|
|
#include <fcntl.h>
|
|
#include "ptrace.h"
|
|
#include <signal.h>
|
|
#include <sys/resource.h>
|
|
#include <sys/wait.h>
|
|
#include <sys/stat.h>
|
|
#ifdef HAVE_PATHS_H
|
|
# include <paths.h>
|
|
#endif
|
|
#include <pwd.h>
|
|
#include <grp.h>
|
|
#include <dirent.h>
|
|
#include <locale.h>
|
|
#include <sys/utsname.h>
|
|
#ifdef HAVE_PRCTL
|
|
# include <sys/prctl.h>
|
|
#endif
|
|
#include <asm/unistd.h>
|
|
|
|
#include "kill_save_errno.h"
|
|
#include "largefile_wrappers.h"
|
|
#include "mmap_cache.h"
|
|
#include "number_set.h"
|
|
#include "ptrace_syscall_info.h"
|
|
#include "scno.h"
|
|
#include "printsiginfo.h"
|
|
#include "trace_event.h"
|
|
#include "xstring.h"
|
|
#include "delay.h"
|
|
|
|
/* In some libc, these aren't declared. Do it ourself: */
|
|
extern char **environ;
|
|
extern int optind;
|
|
extern char *optarg;
|
|
|
|
#ifdef ENABLE_STACKTRACE
|
|
/* if this is true do the stack trace for every system call */
|
|
bool stack_trace_enabled;
|
|
#endif
|
|
|
|
#define my_tkill(tid, sig) syscall(__NR_tkill, (tid), (sig))
|
|
|
|
/* Glue for systems without a MMU that cannot provide fork() */
|
|
#if !defined(HAVE_FORK)
|
|
# undef NOMMU_SYSTEM
|
|
# define NOMMU_SYSTEM 1
|
|
#endif
|
|
#if NOMMU_SYSTEM
|
|
# define fork() vfork()
|
|
#endif
|
|
|
|
const unsigned int syscall_trap_sig = SIGTRAP | 0x80;
|
|
|
|
cflag_t cflag = CFLAG_NONE;
|
|
unsigned int followfork;
|
|
unsigned int ptrace_setoptions = PTRACE_O_TRACESYSGOOD | PTRACE_O_TRACEEXEC
|
|
| PTRACE_O_TRACEEXIT;
|
|
unsigned int xflag;
|
|
bool debug_flag;
|
|
bool Tflag;
|
|
bool iflag;
|
|
bool count_wallclock;
|
|
unsigned int qflag;
|
|
static unsigned int tflag;
|
|
static bool rflag;
|
|
static bool print_pid_pfx;
|
|
|
|
/* -I n */
|
|
enum {
|
|
INTR_NOT_SET = 0,
|
|
INTR_ANYWHERE = 1, /* don't block/ignore any signals */
|
|
INTR_WHILE_WAIT = 2, /* block fatal signals while decoding syscall. default */
|
|
INTR_NEVER = 3, /* block fatal signals. default if '-o FILE PROG' */
|
|
INTR_BLOCK_TSTP_TOO = 4, /* block fatal signals and SIGTSTP (^Z) */
|
|
NUM_INTR_OPTS
|
|
};
|
|
static int opt_intr;
|
|
/* We play with signal mask only if this mode is active: */
|
|
#define interactive (opt_intr == INTR_WHILE_WAIT)
|
|
|
|
/*
|
|
* daemonized_tracer supports -D option.
|
|
* With this option, strace forks twice.
|
|
* Unlike normal case, with -D *grandparent* process exec's,
|
|
* becoming a traced process. Child exits (this prevents traced process
|
|
* from having children it doesn't expect to have), and grandchild
|
|
* attaches to grandparent similarly to strace -p PID.
|
|
* This allows for more transparent interaction in cases
|
|
* when process and its parent are communicating via signals,
|
|
* wait() etc. Without -D, strace process gets lodged in between,
|
|
* disrupting parent<->child link.
|
|
*/
|
|
static bool daemonized_tracer;
|
|
|
|
static int post_attach_sigstop = TCB_IGNORE_ONE_SIGSTOP;
|
|
#define use_seize (post_attach_sigstop == 0)
|
|
|
|
/* Sometimes we want to print only succeeding syscalls. */
|
|
bool not_failing_only;
|
|
|
|
/* Show path associated with fd arguments */
|
|
unsigned int show_fd_path;
|
|
|
|
static bool detach_on_execve;
|
|
|
|
static int exit_code;
|
|
static int strace_child;
|
|
static int strace_tracer_pid;
|
|
|
|
static const char *username;
|
|
static uid_t run_uid;
|
|
static gid_t run_gid;
|
|
|
|
unsigned int max_strlen = DEFAULT_STRLEN;
|
|
static int acolumn = DEFAULT_ACOLUMN;
|
|
static char *acolumn_spaces;
|
|
|
|
/* Default output style for xlat entities */
|
|
enum xlat_style xlat_verbosity = XLAT_STYLE_ABBREV;
|
|
|
|
static const char *outfname;
|
|
/* If -ff, points to stderr. Else, it's our common output log */
|
|
static FILE *shared_log;
|
|
static bool open_append;
|
|
|
|
struct tcb *printing_tcp;
|
|
static struct tcb *current_tcp;
|
|
|
|
struct tcb_wait_data {
|
|
enum trace_event te; /**< Event passed to dispatch_event() */
|
|
int status; /**< status, returned by wait4() */
|
|
siginfo_t si; /**< siginfo, returned by PTRACE_GETSIGINFO */
|
|
};
|
|
|
|
static struct tcb **tcbtab;
|
|
static unsigned int nprocs;
|
|
static size_t tcbtabsize;
|
|
|
|
#ifndef HAVE_PROGRAM_INVOCATION_NAME
|
|
char *program_invocation_name;
|
|
#endif
|
|
|
|
unsigned os_release; /* generated from uname()'s u.release */
|
|
|
|
static void detach(struct tcb *tcp);
|
|
static void cleanup(void);
|
|
static void interrupt(int sig);
|
|
|
|
#ifdef HAVE_SIG_ATOMIC_T
|
|
static volatile sig_atomic_t interrupted, restart_failed;
|
|
#else
|
|
static volatile int interrupted, restart_failed;
|
|
#endif
|
|
|
|
static sigset_t timer_set;
|
|
static void timer_sighandler(int);
|
|
|
|
#ifndef HAVE_STRERROR
|
|
|
|
#if !HAVE_DECL_SYS_ERRLIST
|
|
extern int sys_nerr;
|
|
extern char *sys_errlist[];
|
|
#endif
|
|
|
|
const char *
|
|
strerror(int err_no)
|
|
{
|
|
static char buf[sizeof("Unknown error %d") + sizeof(int)*3];
|
|
|
|
if (err_no < 1 || err_no >= sys_nerr) {
|
|
xsprintf(buf, "Unknown error %d", err_no);
|
|
return buf;
|
|
}
|
|
return sys_errlist[err_no];
|
|
}
|
|
|
|
#endif /* HAVE_STERRROR */
|
|
|
|
static void
|
|
print_version(void)
|
|
{
|
|
static const char features[] =
|
|
#ifdef ENABLE_STACKTRACE
|
|
" stack-trace=" USE_UNWINDER
|
|
#endif
|
|
#ifdef USE_DEMANGLE
|
|
" stack-demangle"
|
|
#endif
|
|
#if SUPPORTED_PERSONALITIES > 1
|
|
# if defined HAVE_M32_MPERS
|
|
" m32-mpers"
|
|
# else
|
|
" no-m32-mpers"
|
|
# endif
|
|
#endif /* SUPPORTED_PERSONALITIES > 1 */
|
|
#if SUPPORTED_PERSONALITIES > 2
|
|
# if defined HAVE_MX32_MPERS
|
|
" mx32-mpers"
|
|
# else
|
|
" no-mx32-mpers"
|
|
# endif
|
|
#endif /* SUPPORTED_PERSONALITIES > 2 */
|
|
"";
|
|
|
|
printf("%s -- version %s\n"
|
|
"Copyright (c) 1991-%s The strace developers <%s>.\n"
|
|
"This is free software; see the source for copying conditions. There is NO\n"
|
|
"warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n",
|
|
PACKAGE_NAME, PACKAGE_VERSION, COPYRIGHT_YEAR, PACKAGE_URL);
|
|
printf("\nOptional features enabled:%s\n",
|
|
features[0] ? features : " (none)");
|
|
}
|
|
|
|
static void
|
|
usage(void)
|
|
{
|
|
printf("\
|
|
usage: strace [-CdffhiqrtttTvVwxxy] [-I n] [-e expr]...\n\
|
|
[-a column] [-o file] [-s strsize] [-P path]...\n\
|
|
-p pid... / [-D] [-E var=val]... [-u username] PROG [ARGS]\n\
|
|
or: strace -c[dfw] [-I n] [-e expr]... [-O overhead] [-S sortby]\n\
|
|
-p pid... / [-D] [-E var=val]... [-u username] PROG [ARGS]\n\
|
|
\n\
|
|
Output format:\n\
|
|
-a column alignment COLUMN for printing syscall results (default %d)\n\
|
|
-i print instruction pointer at time of syscall\n\
|
|
"
|
|
#ifdef ENABLE_STACKTRACE
|
|
"\
|
|
-k obtain stack trace between each syscall\n\
|
|
"
|
|
#endif
|
|
"\
|
|
-o file send trace output to FILE instead of stderr\n\
|
|
-q suppress messages about attaching, detaching, etc.\n\
|
|
-r print relative timestamp\n\
|
|
-s strsize limit length of print strings to STRSIZE chars (default %d)\n\
|
|
-t print absolute timestamp\n\
|
|
-tt print absolute timestamp with usecs\n\
|
|
-T print time spent in each syscall\n\
|
|
-x print non-ascii strings in hex\n\
|
|
-xx print all strings in hex\n\
|
|
-X format set the format for printing of named constants and flags\n\
|
|
-y print paths associated with file descriptor arguments\n\
|
|
-yy print protocol specific information associated with socket file descriptors\n\
|
|
\n\
|
|
Statistics:\n\
|
|
-c count time, calls, and errors for each syscall and report summary\n\
|
|
-C like -c but also print regular output\n\
|
|
-O overhead set overhead for tracing syscalls to OVERHEAD usecs\n\
|
|
-S sortby sort syscall counts by: time, calls, name, nothing (default %s)\n\
|
|
-w summarise syscall latency (default is system time)\n\
|
|
\n\
|
|
Filtering:\n\
|
|
-e expr a qualifying expression: option=[!]all or option=[!]val1[,val2]...\n\
|
|
options: trace, abbrev, verbose, raw, signal, read, write, fault, inject, kvm"
|
|
"\n\
|
|
-P path trace accesses to path\n\
|
|
\n\
|
|
Tracing:\n\
|
|
-b execve detach on execve syscall\n\
|
|
-D run tracer process as a detached grandchild, not as parent\n\
|
|
-f follow forks\n\
|
|
-ff follow forks with output into separate files\n\
|
|
-I interruptible\n\
|
|
1: no signals are blocked\n\
|
|
2: fatal signals are blocked while decoding syscall (default)\n\
|
|
3: fatal signals are always blocked (default if '-o FILE PROG')\n\
|
|
4: fatal signals and SIGTSTP (^Z) are always blocked\n\
|
|
(useful to make 'strace -o FILE PROG' not stop on ^Z)\n\
|
|
\n\
|
|
Startup:\n\
|
|
-E var remove var from the environment for command\n\
|
|
-E var=val put var=val in the environment for command\n\
|
|
-p pid trace process with process id PID, may be repeated\n\
|
|
-u username run command as username handling setuid and/or setgid\n\
|
|
\n\
|
|
Miscellaneous:\n\
|
|
-d enable debug output to stderr\n\
|
|
-v verbose mode: print unabbreviated argv, stat, termios, etc. args\n\
|
|
-h print help message\n\
|
|
-V print version\n\
|
|
"
|
|
/* ancient, no one should use it
|
|
-F -- attempt to follow vforks (deprecated, use -f)\n\
|
|
*/
|
|
/* this is broken, so don't document it
|
|
-z -- print only succeeding syscalls\n\
|
|
*/
|
|
, DEFAULT_ACOLUMN, DEFAULT_STRLEN, DEFAULT_SORTBY);
|
|
exit(0);
|
|
}
|
|
|
|
void ATTRIBUTE_NORETURN
|
|
die(void)
|
|
{
|
|
if (strace_tracer_pid == getpid()) {
|
|
cflag = 0;
|
|
cleanup();
|
|
exit(1);
|
|
}
|
|
|
|
_exit(1);
|
|
}
|
|
|
|
static void
|
|
error_opt_arg(int opt, const char *arg)
|
|
{
|
|
error_msg_and_help("invalid -%c argument: '%s'", opt, arg);
|
|
}
|
|
|
|
static const char *ptrace_attach_cmd;
|
|
|
|
static int
|
|
ptrace_attach_or_seize(int pid)
|
|
{
|
|
int r;
|
|
if (!use_seize)
|
|
return ptrace_attach_cmd = "PTRACE_ATTACH",
|
|
ptrace(PTRACE_ATTACH, pid, 0L, 0L);
|
|
r = ptrace(PTRACE_SEIZE, pid, 0L, (unsigned long) ptrace_setoptions);
|
|
if (r)
|
|
return ptrace_attach_cmd = "PTRACE_SEIZE", r;
|
|
r = ptrace(PTRACE_INTERRUPT, pid, 0L, 0L);
|
|
return ptrace_attach_cmd = "PTRACE_INTERRUPT", r;
|
|
}
|
|
|
|
/*
|
|
* Used when we want to unblock stopped traced process.
|
|
* Should be only used with PTRACE_CONT, PTRACE_DETACH and PTRACE_SYSCALL.
|
|
* Returns 0 on success or if error was ESRCH
|
|
* (presumably process was killed while we talk to it).
|
|
* Otherwise prints error message and returns -1.
|
|
*/
|
|
static int
|
|
ptrace_restart(const unsigned int op, struct tcb *const tcp, unsigned int sig)
|
|
{
|
|
int err;
|
|
const char *msg;
|
|
|
|
errno = 0;
|
|
ptrace(op, tcp->pid, 0L, (unsigned long) sig);
|
|
err = errno;
|
|
if (!err)
|
|
return 0;
|
|
|
|
switch (op) {
|
|
case PTRACE_CONT:
|
|
msg = "CONT";
|
|
break;
|
|
case PTRACE_DETACH:
|
|
msg = "DETACH";
|
|
break;
|
|
case PTRACE_LISTEN:
|
|
msg = "LISTEN";
|
|
break;
|
|
default:
|
|
msg = "SYSCALL";
|
|
}
|
|
|
|
/*
|
|
* Why curcol != 0? Otherwise sometimes we get this:
|
|
*
|
|
* 10252 kill(10253, SIGKILL) = 0
|
|
* <ptrace(SYSCALL,10252):No such process>10253 ...next decode...
|
|
*
|
|
* 10252 died after we retrieved syscall exit data,
|
|
* but before we tried to restart it. Log looks ugly.
|
|
*/
|
|
if (current_tcp && current_tcp->curcol != 0) {
|
|
tprintf(" <ptrace(%s):%s>\n", msg, strerror(err));
|
|
line_ended();
|
|
}
|
|
if (err == ESRCH)
|
|
return 0;
|
|
errno = err;
|
|
perror_msg("ptrace(PTRACE_%s,pid:%d,sig:%u)", msg, tcp->pid, sig);
|
|
return -1;
|
|
}
|
|
|
|
static void
|
|
set_cloexec_flag(int fd)
|
|
{
|
|
int flags, newflags;
|
|
|
|
flags = fcntl(fd, F_GETFD);
|
|
if (flags < 0) {
|
|
/* Can happen only if fd is bad.
|
|
* Should never happen: if it does, we have a bug
|
|
* in the caller. Therefore we just abort
|
|
* instead of propagating the error.
|
|
*/
|
|
perror_msg_and_die("fcntl(%d, F_GETFD)", fd);
|
|
}
|
|
|
|
newflags = flags | FD_CLOEXEC;
|
|
if (flags == newflags)
|
|
return;
|
|
|
|
if (fcntl(fd, F_SETFD, newflags)) /* never fails */
|
|
perror_msg_and_die("fcntl(%d, F_SETFD, %#x)", fd, newflags);
|
|
}
|
|
|
|
/*
|
|
* When strace is setuid executable, we have to swap uids
|
|
* before and after filesystem and process management operations.
|
|
*/
|
|
static void
|
|
swap_uid(void)
|
|
{
|
|
int euid = geteuid(), uid = getuid();
|
|
|
|
if (euid != uid && setreuid(euid, uid) < 0) {
|
|
perror_msg_and_die("setreuid");
|
|
}
|
|
}
|
|
|
|
static FILE *
|
|
strace_fopen(const char *path)
|
|
{
|
|
FILE *fp;
|
|
|
|
swap_uid();
|
|
fp = fopen_stream(path, open_append ? "a" : "w");
|
|
if (!fp)
|
|
perror_msg_and_die("Can't fopen '%s'", path);
|
|
swap_uid();
|
|
set_cloexec_flag(fileno(fp));
|
|
return fp;
|
|
}
|
|
|
|
static int popen_pid;
|
|
|
|
#ifndef _PATH_BSHELL
|
|
# define _PATH_BSHELL "/bin/sh"
|
|
#endif
|
|
|
|
/*
|
|
* We cannot use standard popen(3) here because we have to distinguish
|
|
* popen child process from other processes we trace, and standard popen(3)
|
|
* does not export its child's pid.
|
|
*/
|
|
static FILE *
|
|
strace_popen(const char *command)
|
|
{
|
|
FILE *fp;
|
|
int pid;
|
|
int fds[2];
|
|
|
|
swap_uid();
|
|
if (pipe(fds) < 0)
|
|
perror_msg_and_die("pipe");
|
|
|
|
set_cloexec_flag(fds[1]); /* never fails */
|
|
|
|
pid = vfork();
|
|
if (pid < 0)
|
|
perror_msg_and_die("vfork");
|
|
|
|
if (pid == 0) {
|
|
/* child */
|
|
close(fds[1]);
|
|
if (fds[0] != 0) {
|
|
if (dup2(fds[0], 0))
|
|
perror_msg_and_die("dup2");
|
|
close(fds[0]);
|
|
}
|
|
execl(_PATH_BSHELL, "sh", "-c", command, NULL);
|
|
perror_msg_and_die("Can't execute '%s'", _PATH_BSHELL);
|
|
}
|
|
|
|
/* parent */
|
|
popen_pid = pid;
|
|
close(fds[0]);
|
|
swap_uid();
|
|
fp = fdopen(fds[1], "w");
|
|
if (!fp)
|
|
perror_msg_and_die("fdopen");
|
|
return fp;
|
|
}
|
|
|
|
static void
|
|
outf_perror(const struct tcb * const tcp)
|
|
{
|
|
if (tcp->outf == stderr)
|
|
return;
|
|
|
|
/* This is ugly, but we don't store separate file names */
|
|
if (followfork >= 2)
|
|
perror_msg("%s.%u", outfname, tcp->pid);
|
|
else
|
|
perror_msg("%s", outfname);
|
|
}
|
|
|
|
ATTRIBUTE_FORMAT((printf, 1, 0))
|
|
static void
|
|
tvprintf(const char *const fmt, va_list args)
|
|
{
|
|
if (current_tcp) {
|
|
int n = vfprintf(current_tcp->outf, fmt, args);
|
|
if (n < 0) {
|
|
/* very unlikely due to vfprintf buffering */
|
|
outf_perror(current_tcp);
|
|
} else
|
|
current_tcp->curcol += n;
|
|
}
|
|
}
|
|
|
|
void
|
|
tprintf(const char *fmt, ...)
|
|
{
|
|
va_list args;
|
|
va_start(args, fmt);
|
|
tvprintf(fmt, args);
|
|
va_end(args);
|
|
}
|
|
|
|
#ifndef HAVE_FPUTS_UNLOCKED
|
|
# define fputs_unlocked fputs
|
|
#endif
|
|
|
|
void
|
|
tprints(const char *str)
|
|
{
|
|
if (current_tcp) {
|
|
int n = fputs_unlocked(str, current_tcp->outf);
|
|
if (n >= 0) {
|
|
current_tcp->curcol += strlen(str);
|
|
return;
|
|
}
|
|
/* very unlikely due to fputs_unlocked buffering */
|
|
outf_perror(current_tcp);
|
|
}
|
|
}
|
|
|
|
void
|
|
tprints_comment(const char *const str)
|
|
{
|
|
if (str && *str)
|
|
tprintf(" /* %s */", str);
|
|
}
|
|
|
|
void
|
|
tprintf_comment(const char *fmt, ...)
|
|
{
|
|
if (!fmt || !*fmt)
|
|
return;
|
|
|
|
va_list args;
|
|
va_start(args, fmt);
|
|
tprints(" /* ");
|
|
tvprintf(fmt, args);
|
|
tprints(" */");
|
|
va_end(args);
|
|
}
|
|
|
|
static void
|
|
flush_tcp_output(const struct tcb *const tcp)
|
|
{
|
|
if (fflush(tcp->outf))
|
|
outf_perror(tcp);
|
|
}
|
|
|
|
void
|
|
line_ended(void)
|
|
{
|
|
if (current_tcp) {
|
|
current_tcp->curcol = 0;
|
|
flush_tcp_output(current_tcp);
|
|
}
|
|
if (printing_tcp) {
|
|
printing_tcp->curcol = 0;
|
|
printing_tcp = NULL;
|
|
}
|
|
}
|
|
|
|
void
|
|
set_current_tcp(const struct tcb *tcp)
|
|
{
|
|
current_tcp = (struct tcb *) tcp;
|
|
|
|
/* Sync current_personality and stuff */
|
|
if (current_tcp)
|
|
set_personality(current_tcp->currpers);
|
|
}
|
|
|
|
void
|
|
printleader(struct tcb *tcp)
|
|
{
|
|
/* If -ff, "previous tcb we printed" is always the same as current,
|
|
* because we have per-tcb output files.
|
|
*/
|
|
if (followfork >= 2)
|
|
printing_tcp = tcp;
|
|
|
|
if (printing_tcp) {
|
|
set_current_tcp(printing_tcp);
|
|
if (printing_tcp->curcol != 0 && (followfork < 2 || printing_tcp == tcp)) {
|
|
/*
|
|
* case 1: we have a shared log (i.e. not -ff), and last line
|
|
* wasn't finished (same or different tcb, doesn't matter).
|
|
* case 2: split log, we are the same tcb, but our last line
|
|
* didn't finish ("SIGKILL nuked us after syscall entry" etc).
|
|
*/
|
|
tprints(" <unfinished ...>\n");
|
|
printing_tcp->curcol = 0;
|
|
}
|
|
}
|
|
|
|
printing_tcp = tcp;
|
|
set_current_tcp(tcp);
|
|
current_tcp->curcol = 0;
|
|
|
|
if (print_pid_pfx)
|
|
tprintf("%-5d ", tcp->pid);
|
|
else if (nprocs > 1 && !outfname)
|
|
tprintf("[pid %5u] ", tcp->pid);
|
|
|
|
if (tflag) {
|
|
struct timespec ts;
|
|
clock_gettime(CLOCK_REALTIME, &ts);
|
|
|
|
if (tflag > 2) {
|
|
tprintf("%lld.%06ld ",
|
|
(long long) ts.tv_sec, (long) ts.tv_nsec / 1000);
|
|
} else {
|
|
time_t local = ts.tv_sec;
|
|
char str[MAX(sizeof("HH:MM:SS"), sizeof(ts.tv_sec) * 3)];
|
|
struct tm *tm = localtime(&local);
|
|
|
|
if (tm)
|
|
strftime(str, sizeof(str), "%T", tm);
|
|
else
|
|
xsprintf(str, "%lld", (long long) local);
|
|
if (tflag > 1)
|
|
tprintf("%s.%06ld ",
|
|
str, (long) ts.tv_nsec / 1000);
|
|
else
|
|
tprintf("%s ", str);
|
|
}
|
|
}
|
|
|
|
if (rflag) {
|
|
struct timespec ts;
|
|
clock_gettime(CLOCK_MONOTONIC, &ts);
|
|
|
|
static struct timespec ots;
|
|
if (ots.tv_sec == 0)
|
|
ots = ts;
|
|
|
|
struct timespec dts;
|
|
ts_sub(&dts, &ts, &ots);
|
|
ots = ts;
|
|
|
|
tprintf("%s%6ld.%06ld%s ",
|
|
tflag ? "(+" : "",
|
|
(long) dts.tv_sec, (long) dts.tv_nsec / 1000,
|
|
tflag ? ")" : "");
|
|
}
|
|
|
|
if (iflag)
|
|
print_instruction_pointer(tcp);
|
|
}
|
|
|
|
void
|
|
tabto(void)
|
|
{
|
|
if (current_tcp->curcol < acolumn)
|
|
tprints(acolumn_spaces + current_tcp->curcol);
|
|
}
|
|
|
|
/* Should be only called directly *after successful attach* to a tracee.
|
|
* Otherwise, "strace -oFILE -ff -p<nonexistant_pid>"
|
|
* may create bogus empty FILE.<nonexistant_pid>, and then die.
|
|
*/
|
|
static void
|
|
after_successful_attach(struct tcb *tcp, const unsigned int flags)
|
|
{
|
|
tcp->flags |= TCB_ATTACHED | TCB_STARTUP | flags;
|
|
tcp->outf = shared_log; /* if not -ff mode, the same file is for all */
|
|
if (followfork >= 2) {
|
|
char name[PATH_MAX];
|
|
xsprintf(name, "%s.%u", outfname, tcp->pid);
|
|
tcp->outf = strace_fopen(name);
|
|
}
|
|
|
|
#ifdef ENABLE_STACKTRACE
|
|
if (stack_trace_enabled)
|
|
unwind_tcb_init(tcp);
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
expand_tcbtab(void)
|
|
{
|
|
/* Allocate some (more) TCBs (and expand the table).
|
|
We don't want to relocate the TCBs because our
|
|
callers have pointers and it would be a pain.
|
|
So tcbtab is a table of pointers. Since we never
|
|
free the TCBs, we allocate a single chunk of many. */
|
|
size_t old_tcbtabsize;
|
|
struct tcb *newtcbs;
|
|
struct tcb **tcb_ptr;
|
|
|
|
old_tcbtabsize = tcbtabsize;
|
|
|
|
tcbtab = xgrowarray(tcbtab, &tcbtabsize, sizeof(tcbtab[0]));
|
|
newtcbs = xcalloc(tcbtabsize - old_tcbtabsize, sizeof(newtcbs[0]));
|
|
|
|
for (tcb_ptr = tcbtab + old_tcbtabsize;
|
|
tcb_ptr < tcbtab + tcbtabsize; tcb_ptr++, newtcbs++)
|
|
*tcb_ptr = newtcbs;
|
|
}
|
|
|
|
static struct tcb *
|
|
alloctcb(int pid)
|
|
{
|
|
unsigned int i;
|
|
struct tcb *tcp;
|
|
|
|
if (nprocs == tcbtabsize)
|
|
expand_tcbtab();
|
|
|
|
for (i = 0; i < tcbtabsize; i++) {
|
|
tcp = tcbtab[i];
|
|
if (!tcp->pid) {
|
|
memset(tcp, 0, sizeof(*tcp));
|
|
tcp->pid = pid;
|
|
#if SUPPORTED_PERSONALITIES > 1
|
|
tcp->currpers = current_personality;
|
|
#endif
|
|
nprocs++;
|
|
debug_msg("new tcb for pid %d, active tcbs:%d",
|
|
tcp->pid, nprocs);
|
|
return tcp;
|
|
}
|
|
}
|
|
error_msg_and_die("bug in alloctcb");
|
|
}
|
|
|
|
void *
|
|
get_tcb_priv_data(const struct tcb *tcp)
|
|
{
|
|
return tcp->_priv_data;
|
|
}
|
|
|
|
int
|
|
set_tcb_priv_data(struct tcb *tcp, void *const priv_data,
|
|
void (*const free_priv_data)(void *))
|
|
{
|
|
if (tcp->_priv_data)
|
|
return -1;
|
|
|
|
tcp->_free_priv_data = free_priv_data;
|
|
tcp->_priv_data = priv_data;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
free_tcb_priv_data(struct tcb *tcp)
|
|
{
|
|
if (tcp->_priv_data) {
|
|
if (tcp->_free_priv_data) {
|
|
tcp->_free_priv_data(tcp->_priv_data);
|
|
tcp->_free_priv_data = NULL;
|
|
}
|
|
tcp->_priv_data = NULL;
|
|
}
|
|
}
|
|
|
|
static void
|
|
droptcb(struct tcb *tcp)
|
|
{
|
|
if (tcp->pid == 0)
|
|
return;
|
|
|
|
int p;
|
|
for (p = 0; p < SUPPORTED_PERSONALITIES; ++p)
|
|
free(tcp->inject_vec[p]);
|
|
|
|
free_tcb_priv_data(tcp);
|
|
|
|
#ifdef ENABLE_STACKTRACE
|
|
if (stack_trace_enabled)
|
|
unwind_tcb_fin(tcp);
|
|
#endif
|
|
|
|
#ifdef HAVE_LINUX_KVM_H
|
|
kvm_vcpu_info_free(tcp);
|
|
#endif
|
|
|
|
if (tcp->mmap_cache)
|
|
tcp->mmap_cache->free_fn(tcp, __func__);
|
|
|
|
nprocs--;
|
|
debug_msg("dropped tcb for pid %d, %d remain", tcp->pid, nprocs);
|
|
|
|
if (tcp->outf) {
|
|
if (followfork >= 2) {
|
|
if (tcp->curcol != 0)
|
|
fprintf(tcp->outf, " <detached ...>\n");
|
|
fclose(tcp->outf);
|
|
} else {
|
|
if (printing_tcp == tcp && tcp->curcol != 0)
|
|
fprintf(tcp->outf, " <detached ...>\n");
|
|
flush_tcp_output(tcp);
|
|
}
|
|
}
|
|
|
|
if (current_tcp == tcp)
|
|
set_current_tcp(NULL);
|
|
if (printing_tcp == tcp)
|
|
printing_tcp = NULL;
|
|
|
|
memset(tcp, 0, sizeof(*tcp));
|
|
}
|
|
|
|
/* Detach traced process.
|
|
* Never call DETACH twice on the same process as both unattached and
|
|
* attached-unstopped processes give the same ESRCH. For unattached process we
|
|
* would SIGSTOP it and wait for its SIGSTOP notification forever.
|
|
*/
|
|
static void
|
|
detach(struct tcb *tcp)
|
|
{
|
|
int error;
|
|
int status;
|
|
|
|
/*
|
|
* Linux wrongly insists the child be stopped
|
|
* before detaching. Arghh. We go through hoops
|
|
* to make a clean break of things.
|
|
*/
|
|
|
|
if (!(tcp->flags & TCB_ATTACHED))
|
|
goto drop;
|
|
|
|
/* We attached but possibly didn't see the expected SIGSTOP.
|
|
* We must catch exactly one as otherwise the detached process
|
|
* would be left stopped (process state T).
|
|
*/
|
|
if (tcp->flags & TCB_IGNORE_ONE_SIGSTOP)
|
|
goto wait_loop;
|
|
|
|
error = ptrace(PTRACE_DETACH, tcp->pid, 0, 0);
|
|
if (!error) {
|
|
/* On a clear day, you can see forever. */
|
|
goto drop;
|
|
}
|
|
if (errno != ESRCH) {
|
|
/* Shouldn't happen. */
|
|
perror_func_msg("ptrace(PTRACE_DETACH,%u)", tcp->pid);
|
|
goto drop;
|
|
}
|
|
/* ESRCH: process is either not stopped or doesn't exist. */
|
|
if (my_tkill(tcp->pid, 0) < 0) {
|
|
if (errno != ESRCH)
|
|
/* Shouldn't happen. */
|
|
perror_func_msg("tkill(%u,0)", tcp->pid);
|
|
/* else: process doesn't exist. */
|
|
goto drop;
|
|
}
|
|
/* Process is not stopped, need to stop it. */
|
|
if (use_seize) {
|
|
/*
|
|
* With SEIZE, tracee can be in group-stop already.
|
|
* In this state sending it another SIGSTOP does nothing.
|
|
* Need to use INTERRUPT.
|
|
* Testcase: trying to ^C a "strace -p <stopped_process>".
|
|
*/
|
|
error = ptrace(PTRACE_INTERRUPT, tcp->pid, 0, 0);
|
|
if (!error)
|
|
goto wait_loop;
|
|
if (errno != ESRCH)
|
|
perror_func_msg("ptrace(PTRACE_INTERRUPT,%u)", tcp->pid);
|
|
} else {
|
|
error = my_tkill(tcp->pid, SIGSTOP);
|
|
if (!error)
|
|
goto wait_loop;
|
|
if (errno != ESRCH)
|
|
perror_func_msg("tkill(%u,SIGSTOP)", tcp->pid);
|
|
}
|
|
/* Either process doesn't exist, or some weird error. */
|
|
goto drop;
|
|
|
|
wait_loop:
|
|
/* We end up here in three cases:
|
|
* 1. We sent PTRACE_INTERRUPT (use_seize case)
|
|
* 2. We sent SIGSTOP (!use_seize)
|
|
* 3. Attach SIGSTOP was already pending (TCB_IGNORE_ONE_SIGSTOP set)
|
|
*/
|
|
for (;;) {
|
|
unsigned int sig;
|
|
if (waitpid(tcp->pid, &status, __WALL) < 0) {
|
|
if (errno == EINTR)
|
|
continue;
|
|
/*
|
|
* if (errno == ECHILD) break;
|
|
* ^^^ WRONG! We expect this PID to exist,
|
|
* and want to emit a message otherwise:
|
|
*/
|
|
perror_func_msg("waitpid(%u)", tcp->pid);
|
|
break;
|
|
}
|
|
if (!WIFSTOPPED(status)) {
|
|
/*
|
|
* Tracee exited or was killed by signal.
|
|
* We shouldn't normally reach this place:
|
|
* we don't want to consume exit status.
|
|
* Consider "strace -p PID" being ^C-ed:
|
|
* we want merely to detach from PID.
|
|
*
|
|
* However, we _can_ end up here if tracee
|
|
* was SIGKILLed.
|
|
*/
|
|
break;
|
|
}
|
|
sig = WSTOPSIG(status);
|
|
debug_msg("detach wait: event:%d sig:%d",
|
|
(unsigned) status >> 16, sig);
|
|
if (use_seize) {
|
|
unsigned event = (unsigned)status >> 16;
|
|
if (event == PTRACE_EVENT_STOP /*&& sig == SIGTRAP*/) {
|
|
/*
|
|
* sig == SIGTRAP: PTRACE_INTERRUPT stop.
|
|
* sig == other: process was already stopped
|
|
* with this stopping sig (see tests/detach-stopped).
|
|
* Looks like re-injecting this sig is not necessary
|
|
* in DETACH for the tracee to remain stopped.
|
|
*/
|
|
sig = 0;
|
|
}
|
|
/*
|
|
* PTRACE_INTERRUPT is not guaranteed to produce
|
|
* the above event if other ptrace-stop is pending.
|
|
* See tests/detach-sleeping testcase:
|
|
* strace got SIGINT while tracee is sleeping.
|
|
* We sent PTRACE_INTERRUPT.
|
|
* We see syscall exit, not PTRACE_INTERRUPT stop.
|
|
* We won't get PTRACE_INTERRUPT stop
|
|
* if we would CONT now. Need to DETACH.
|
|
*/
|
|
if (sig == syscall_trap_sig)
|
|
sig = 0;
|
|
/* else: not sure in which case we can be here.
|
|
* Signal stop? Inject it while detaching.
|
|
*/
|
|
ptrace_restart(PTRACE_DETACH, tcp, sig);
|
|
break;
|
|
}
|
|
/* Note: this check has to be after use_seize check */
|
|
/* (else, in use_seize case SIGSTOP will be mistreated) */
|
|
if (sig == SIGSTOP) {
|
|
/* Detach, suppressing SIGSTOP */
|
|
ptrace_restart(PTRACE_DETACH, tcp, 0);
|
|
break;
|
|
}
|
|
if (sig == syscall_trap_sig)
|
|
sig = 0;
|
|
/* Can't detach just yet, may need to wait for SIGSTOP */
|
|
error = ptrace_restart(PTRACE_CONT, tcp, sig);
|
|
if (error < 0) {
|
|
/* Should not happen.
|
|
* Note: ptrace_restart returns 0 on ESRCH, so it's not it.
|
|
* ptrace_restart already emitted error message.
|
|
*/
|
|
break;
|
|
}
|
|
}
|
|
|
|
drop:
|
|
if (!qflag && (tcp->flags & TCB_ATTACHED))
|
|
error_msg("Process %u detached", tcp->pid);
|
|
|
|
droptcb(tcp);
|
|
}
|
|
|
|
static void
|
|
process_opt_p_list(char *opt)
|
|
{
|
|
while (*opt) {
|
|
/*
|
|
* We accept -p PID,PID; -p "`pidof PROG`"; -p "`pgrep PROG`".
|
|
* pidof uses space as delim, pgrep uses newline. :(
|
|
*/
|
|
int pid;
|
|
char *delim = opt + strcspn(opt, "\n\t ,");
|
|
char c = *delim;
|
|
|
|
*delim = '\0';
|
|
pid = string_to_uint(opt);
|
|
if (pid <= 0) {
|
|
error_msg_and_die("Invalid process id: '%s'", opt);
|
|
}
|
|
if (pid == strace_tracer_pid) {
|
|
error_msg_and_die("I'm sorry, I can't let you do that, Dave.");
|
|
}
|
|
*delim = c;
|
|
alloctcb(pid);
|
|
if (c == '\0')
|
|
break;
|
|
opt = delim + 1;
|
|
}
|
|
}
|
|
|
|
static void
|
|
attach_tcb(struct tcb *const tcp)
|
|
{
|
|
if (ptrace_attach_or_seize(tcp->pid) < 0) {
|
|
perror_msg("attach: ptrace(%s, %d)",
|
|
ptrace_attach_cmd, tcp->pid);
|
|
droptcb(tcp);
|
|
return;
|
|
}
|
|
|
|
after_successful_attach(tcp, TCB_GRABBED | post_attach_sigstop);
|
|
debug_msg("attach to pid %d (main) succeeded", tcp->pid);
|
|
|
|
static const char task_path[] = "/proc/%d/task";
|
|
char procdir[sizeof(task_path) + sizeof(int) * 3];
|
|
DIR *dir;
|
|
unsigned int ntid = 0, nerr = 0;
|
|
|
|
if (followfork && tcp->pid != strace_child &&
|
|
xsprintf(procdir, task_path, tcp->pid) > 0 &&
|
|
(dir = opendir(procdir)) != NULL) {
|
|
struct_dirent *de;
|
|
|
|
while ((de = read_dir(dir)) != NULL) {
|
|
if (de->d_fileno == 0)
|
|
continue;
|
|
|
|
int tid = string_to_uint(de->d_name);
|
|
if (tid <= 0 || tid == tcp->pid)
|
|
continue;
|
|
|
|
++ntid;
|
|
if (ptrace_attach_or_seize(tid) < 0) {
|
|
++nerr;
|
|
debug_perror_msg("attach: ptrace(%s, %d)",
|
|
ptrace_attach_cmd, tid);
|
|
continue;
|
|
}
|
|
|
|
after_successful_attach(alloctcb(tid),
|
|
TCB_GRABBED | post_attach_sigstop);
|
|
debug_msg("attach to pid %d succeeded", tid);
|
|
}
|
|
|
|
closedir(dir);
|
|
}
|
|
|
|
if (!qflag) {
|
|
if (ntid > nerr)
|
|
error_msg("Process %u attached"
|
|
" with %u threads",
|
|
tcp->pid, ntid - nerr + 1);
|
|
else
|
|
error_msg("Process %u attached",
|
|
tcp->pid);
|
|
}
|
|
}
|
|
|
|
static void
|
|
startup_attach(void)
|
|
{
|
|
pid_t parent_pid = strace_tracer_pid;
|
|
unsigned int tcbi;
|
|
struct tcb *tcp;
|
|
|
|
if (daemonized_tracer) {
|
|
pid_t pid = fork();
|
|
if (pid < 0)
|
|
perror_func_msg_and_die("fork");
|
|
|
|
if (pid) { /* parent */
|
|
/*
|
|
* Wait for grandchild to attach to straced process
|
|
* (grandparent). Grandchild SIGKILLs us after it attached.
|
|
* Grandparent's wait() is unblocked by our death,
|
|
* it proceeds to exec the straced program.
|
|
*/
|
|
pause();
|
|
_exit(0); /* paranoia */
|
|
}
|
|
/* grandchild */
|
|
/* We will be the tracer process. Remember our new pid: */
|
|
strace_tracer_pid = getpid();
|
|
}
|
|
|
|
for (tcbi = 0; tcbi < tcbtabsize; tcbi++) {
|
|
tcp = tcbtab[tcbi];
|
|
|
|
if (!tcp->pid)
|
|
continue;
|
|
|
|
/* Is this a process we should attach to, but not yet attached? */
|
|
if (tcp->flags & TCB_ATTACHED)
|
|
continue; /* no, we already attached it */
|
|
|
|
if (tcp->pid == parent_pid || tcp->pid == strace_tracer_pid) {
|
|
errno = EPERM;
|
|
perror_msg("attach: pid %d", tcp->pid);
|
|
droptcb(tcp);
|
|
continue;
|
|
}
|
|
|
|
attach_tcb(tcp);
|
|
|
|
if (interrupted)
|
|
return;
|
|
} /* for each tcbtab[] */
|
|
|
|
if (daemonized_tracer) {
|
|
/*
|
|
* Make parent go away.
|
|
* Also makes grandparent's wait() unblock.
|
|
*/
|
|
kill(parent_pid, SIGKILL);
|
|
strace_child = 0;
|
|
}
|
|
}
|
|
|
|
/* Stack-o-phobic exec helper, in the hope to work around
|
|
* NOMMU + "daemonized tracer" difficulty.
|
|
*/
|
|
struct exec_params {
|
|
int fd_to_close;
|
|
uid_t run_euid;
|
|
gid_t run_egid;
|
|
char **argv;
|
|
char *pathname;
|
|
struct sigaction child_sa;
|
|
};
|
|
static struct exec_params params_for_tracee;
|
|
|
|
static void ATTRIBUTE_NOINLINE ATTRIBUTE_NORETURN
|
|
exec_or_die(void)
|
|
{
|
|
struct exec_params *params = ¶ms_for_tracee;
|
|
|
|
if (params->fd_to_close >= 0)
|
|
close(params->fd_to_close);
|
|
if (!daemonized_tracer && !use_seize) {
|
|
if (ptrace(PTRACE_TRACEME, 0L, 0L, 0L) < 0) {
|
|
perror_msg_and_die("ptrace(PTRACE_TRACEME, ...)");
|
|
}
|
|
}
|
|
|
|
if (username != NULL) {
|
|
/*
|
|
* It is important to set groups before we
|
|
* lose privileges on setuid.
|
|
*/
|
|
if (initgroups(username, run_gid) < 0) {
|
|
perror_msg_and_die("initgroups");
|
|
}
|
|
if (setregid(run_gid, params->run_egid) < 0) {
|
|
perror_msg_and_die("setregid");
|
|
}
|
|
if (setreuid(run_uid, params->run_euid) < 0) {
|
|
perror_msg_and_die("setreuid");
|
|
}
|
|
} else if (geteuid() != 0)
|
|
if (setreuid(run_uid, run_uid) < 0) {
|
|
perror_msg_and_die("setreuid");
|
|
}
|
|
|
|
if (!daemonized_tracer) {
|
|
/*
|
|
* Induce a ptrace stop. Tracer (our parent)
|
|
* will resume us with PTRACE_SYSCALL and display
|
|
* the immediately following execve syscall.
|
|
* Can't do this on NOMMU systems, we are after
|
|
* vfork: parent is blocked, stopping would deadlock.
|
|
*/
|
|
if (!NOMMU_SYSTEM)
|
|
kill(getpid(), SIGSTOP);
|
|
} else {
|
|
alarm(3);
|
|
/* we depend on SIGCHLD set to SIG_DFL by init code */
|
|
/* if it happens to be SIG_IGN'ed, wait won't block */
|
|
wait(NULL);
|
|
alarm(0);
|
|
}
|
|
|
|
if (params_for_tracee.child_sa.sa_handler != SIG_DFL)
|
|
sigaction(SIGCHLD, ¶ms_for_tracee.child_sa, NULL);
|
|
|
|
execv(params->pathname, params->argv);
|
|
perror_msg_and_die("exec");
|
|
}
|
|
|
|
/*
|
|
* Open a dummy descriptor for use as a placeholder.
|
|
* The descriptor is O_RDONLY with FD_CLOEXEC flag set.
|
|
* A read attempt from such descriptor ends with EOF,
|
|
* a write attempt is rejected with EBADF.
|
|
*/
|
|
static int
|
|
open_dummy_desc(void)
|
|
{
|
|
int fds[2];
|
|
|
|
if (pipe(fds))
|
|
perror_func_msg_and_die("pipe");
|
|
close(fds[1]);
|
|
set_cloexec_flag(fds[0]);
|
|
return fds[0];
|
|
}
|
|
|
|
/* placeholder fds status for stdin and stdout */
|
|
static bool fd_is_placeholder[2];
|
|
|
|
/*
|
|
* Ensure that all standard file descriptors are open by opening placeholder
|
|
* file descriptors for those standard file descriptors that are not open.
|
|
*
|
|
* The information which descriptors have been made open is saved
|
|
* in fd_is_placeholder for later use.
|
|
*/
|
|
static void
|
|
ensure_standard_fds_opened(void)
|
|
{
|
|
int fd;
|
|
|
|
while ((fd = open_dummy_desc()) <= 2) {
|
|
if (fd == 2)
|
|
break;
|
|
fd_is_placeholder[fd] = true;
|
|
}
|
|
|
|
if (fd > 2)
|
|
close(fd);
|
|
}
|
|
|
|
/*
|
|
* Redirect stdin and stdout unless they have been opened earlier
|
|
* by ensure_standard_fds_opened as placeholders.
|
|
*/
|
|
static void
|
|
redirect_standard_fds(void)
|
|
{
|
|
int i;
|
|
|
|
/*
|
|
* It might be a good idea to redirect stderr as well,
|
|
* but we sometimes need to print error messages.
|
|
*/
|
|
for (i = 0; i <= 1; ++i) {
|
|
if (!fd_is_placeholder[i]) {
|
|
close(i);
|
|
open_dummy_desc();
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
startup_child(char **argv)
|
|
{
|
|
struct_stat statbuf;
|
|
const char *filename;
|
|
size_t filename_len;
|
|
char pathname[PATH_MAX];
|
|
int pid;
|
|
struct tcb *tcp;
|
|
|
|
filename = argv[0];
|
|
filename_len = strlen(filename);
|
|
|
|
if (filename_len > sizeof(pathname) - 1) {
|
|
errno = ENAMETOOLONG;
|
|
perror_msg_and_die("exec");
|
|
}
|
|
if (strchr(filename, '/')) {
|
|
strcpy(pathname, filename);
|
|
}
|
|
#ifdef USE_DEBUGGING_EXEC
|
|
/*
|
|
* Debuggers customarily check the current directory
|
|
* first regardless of the path but doing that gives
|
|
* security geeks a panic attack.
|
|
*/
|
|
else if (stat_file(filename, &statbuf) == 0)
|
|
strcpy(pathname, filename);
|
|
#endif /* USE_DEBUGGING_EXEC */
|
|
else {
|
|
const char *path;
|
|
size_t m, n, len;
|
|
|
|
for (path = getenv("PATH"); path && *path; path += m) {
|
|
const char *colon = strchr(path, ':');
|
|
if (colon) {
|
|
n = colon - path;
|
|
m = n + 1;
|
|
} else
|
|
m = n = strlen(path);
|
|
if (n == 0) {
|
|
if (!getcwd(pathname, PATH_MAX))
|
|
continue;
|
|
len = strlen(pathname);
|
|
} else if (n > sizeof(pathname) - 1)
|
|
continue;
|
|
else {
|
|
strncpy(pathname, path, n);
|
|
len = n;
|
|
}
|
|
if (len && pathname[len - 1] != '/')
|
|
pathname[len++] = '/';
|
|
if (filename_len + len > sizeof(pathname) - 1)
|
|
continue;
|
|
strcpy(pathname + len, filename);
|
|
if (stat_file(pathname, &statbuf) == 0 &&
|
|
/* Accept only regular files
|
|
with some execute bits set.
|
|
XXX not perfect, might still fail */
|
|
S_ISREG(statbuf.st_mode) &&
|
|
(statbuf.st_mode & 0111))
|
|
break;
|
|
}
|
|
if (!path || !*path)
|
|
pathname[0] = '\0';
|
|
}
|
|
if (stat_file(pathname, &statbuf) < 0) {
|
|
perror_msg_and_die("Can't stat '%s'", filename);
|
|
}
|
|
|
|
params_for_tracee.fd_to_close = (shared_log != stderr) ? fileno(shared_log) : -1;
|
|
params_for_tracee.run_euid = (statbuf.st_mode & S_ISUID) ? statbuf.st_uid : run_uid;
|
|
params_for_tracee.run_egid = (statbuf.st_mode & S_ISGID) ? statbuf.st_gid : run_gid;
|
|
params_for_tracee.argv = argv;
|
|
/*
|
|
* On NOMMU, can be safely freed only after execve in tracee.
|
|
* It's hard to know when that happens, so we just leak it.
|
|
*/
|
|
params_for_tracee.pathname = NOMMU_SYSTEM ? xstrdup(pathname) : pathname;
|
|
|
|
#if defined HAVE_PRCTL && defined PR_SET_PTRACER && defined PR_SET_PTRACER_ANY
|
|
if (daemonized_tracer)
|
|
prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY);
|
|
#endif
|
|
|
|
pid = fork();
|
|
if (pid < 0)
|
|
perror_func_msg_and_die("fork");
|
|
|
|
if ((pid != 0 && daemonized_tracer)
|
|
|| (pid == 0 && !daemonized_tracer)
|
|
) {
|
|
/* We are to become the tracee. Two cases:
|
|
* -D: we are parent
|
|
* not -D: we are child
|
|
*/
|
|
exec_or_die();
|
|
}
|
|
|
|
/* We are the tracer */
|
|
|
|
if (!daemonized_tracer) {
|
|
strace_child = pid;
|
|
if (!use_seize) {
|
|
/* child did PTRACE_TRACEME, nothing to do in parent */
|
|
} else {
|
|
if (!NOMMU_SYSTEM) {
|
|
/* Wait until child stopped itself */
|
|
int status;
|
|
while (waitpid(pid, &status, WSTOPPED) < 0) {
|
|
if (errno == EINTR)
|
|
continue;
|
|
perror_msg_and_die("waitpid");
|
|
}
|
|
if (!WIFSTOPPED(status) || WSTOPSIG(status) != SIGSTOP) {
|
|
kill_save_errno(pid, SIGKILL);
|
|
perror_msg_and_die("Unexpected wait status %#x",
|
|
status);
|
|
}
|
|
}
|
|
/* Else: NOMMU case, we have no way to sync.
|
|
* Just attach to it as soon as possible.
|
|
* This means that we may miss a few first syscalls...
|
|
*/
|
|
|
|
if (ptrace_attach_or_seize(pid)) {
|
|
kill_save_errno(pid, SIGKILL);
|
|
perror_msg_and_die("attach: ptrace(%s, %d)",
|
|
ptrace_attach_cmd, pid);
|
|
}
|
|
if (!NOMMU_SYSTEM)
|
|
kill(pid, SIGCONT);
|
|
}
|
|
tcp = alloctcb(pid);
|
|
after_successful_attach(tcp, TCB_SKIP_DETACH_ON_FIRST_EXEC
|
|
| (NOMMU_SYSTEM ? 0
|
|
: (TCB_HIDE_LOG
|
|
| post_attach_sigstop)));
|
|
} else {
|
|
/* With -D, we are *child* here, the tracee is our parent. */
|
|
strace_child = strace_tracer_pid;
|
|
strace_tracer_pid = getpid();
|
|
tcp = alloctcb(strace_child);
|
|
tcp->flags |= TCB_SKIP_DETACH_ON_FIRST_EXEC | TCB_HIDE_LOG;
|
|
/*
|
|
* Attaching will be done later, by startup_attach.
|
|
* Note: we don't do after_successful_attach() here either!
|
|
*/
|
|
|
|
/* NOMMU BUG! -D mode is active, we (child) return,
|
|
* and we will scribble over parent's stack!
|
|
* When parent later unpauses, it segfaults.
|
|
*
|
|
* We work around it
|
|
* (1) by declaring exec_or_die() NORETURN,
|
|
* hopefully compiler will just jump to it
|
|
* instead of call (won't push anything to stack),
|
|
* (2) by trying very hard in exec_or_die()
|
|
* to not use any stack,
|
|
* (3) having a really big (PATH_MAX) stack object
|
|
* in this function, which creates a "buffer" between
|
|
* child's and parent's stack pointers.
|
|
* This may save us if (1) and (2) failed
|
|
* and compiler decided to use stack in exec_or_die() anyway
|
|
* (happens on i386 because of stack parameter passing).
|
|
*
|
|
* A cleaner solution is to use makecontext + setcontext
|
|
* to create a genuine separate stack and execute on it.
|
|
*/
|
|
}
|
|
/*
|
|
* A case where straced process is part of a pipe:
|
|
* { sleep 1; yes | head -n99999; } | strace -o/dev/null sh -c 'exec <&-; sleep 9'
|
|
* If strace won't close its fd#0, closing it in tracee is not enough:
|
|
* the pipe is still open, it has a reader. Thus, "head" will not get its
|
|
* SIGPIPE at once, on the first write.
|
|
*
|
|
* Preventing it by redirecting strace's stdin/out.
|
|
* (Don't leave fds 0 and 1 closed, this is bad practice: future opens
|
|
* will reuse them, unexpectedly making a newly opened object "stdin").
|
|
*/
|
|
redirect_standard_fds();
|
|
}
|
|
|
|
static void
|
|
test_ptrace_seize(void)
|
|
{
|
|
int pid;
|
|
|
|
/* Need fork for test. NOMMU has no forks */
|
|
if (NOMMU_SYSTEM) {
|
|
post_attach_sigstop = 0; /* this sets use_seize to 1 */
|
|
return;
|
|
}
|
|
|
|
pid = fork();
|
|
if (pid < 0)
|
|
perror_func_msg_and_die("fork");
|
|
|
|
if (pid == 0) {
|
|
pause();
|
|
_exit(0);
|
|
}
|
|
|
|
/* PTRACE_SEIZE, unlike ATTACH, doesn't force tracee to trap. After
|
|
* attaching tracee continues to run unless a trap condition occurs.
|
|
* PTRACE_SEIZE doesn't affect signal or group stop state.
|
|
*/
|
|
if (ptrace(PTRACE_SEIZE, pid, 0, 0) == 0) {
|
|
post_attach_sigstop = 0; /* this sets use_seize to 1 */
|
|
} else {
|
|
debug_msg("PTRACE_SEIZE doesn't work");
|
|
}
|
|
|
|
kill(pid, SIGKILL);
|
|
|
|
while (1) {
|
|
int status, tracee_pid;
|
|
|
|
errno = 0;
|
|
tracee_pid = waitpid(pid, &status, 0);
|
|
if (tracee_pid <= 0) {
|
|
if (errno == EINTR)
|
|
continue;
|
|
perror_func_msg_and_die("unexpected wait result %d",
|
|
tracee_pid);
|
|
}
|
|
if (WIFSIGNALED(status))
|
|
return;
|
|
|
|
error_func_msg_and_die("unexpected wait status %#x", status);
|
|
}
|
|
}
|
|
|
|
static unsigned
|
|
get_os_release(void)
|
|
{
|
|
unsigned rel;
|
|
const char *p;
|
|
struct utsname u;
|
|
if (uname(&u) < 0)
|
|
perror_msg_and_die("uname");
|
|
/* u.release has this form: "3.2.9[-some-garbage]" */
|
|
rel = 0;
|
|
p = u.release;
|
|
for (;;) {
|
|
if (!(*p >= '0' && *p <= '9'))
|
|
error_msg_and_die("Bad OS release string: '%s'", u.release);
|
|
/* Note: this open-codes KERNEL_VERSION(): */
|
|
rel = (rel << 8) | atoi(p);
|
|
if (rel >= KERNEL_VERSION(1, 0, 0))
|
|
break;
|
|
while (*p >= '0' && *p <= '9')
|
|
p++;
|
|
if (*p != '.') {
|
|
if (rel >= KERNEL_VERSION(0, 1, 0)) {
|
|
/* "X.Y-something" means "X.Y.0" */
|
|
rel <<= 8;
|
|
break;
|
|
}
|
|
error_msg_and_die("Bad OS release string: '%s'", u.release);
|
|
}
|
|
p++;
|
|
}
|
|
return rel;
|
|
}
|
|
|
|
static void
|
|
set_sighandler(int signo, void (*sighandler)(int), struct sigaction *oldact)
|
|
{
|
|
const struct sigaction sa = { .sa_handler = sighandler };
|
|
sigaction(signo, &sa, oldact);
|
|
}
|
|
|
|
/*
|
|
* Initialization part of main() was eating much stack (~0.5k),
|
|
* which was unused after init.
|
|
* We can reuse it if we move init code into a separate function.
|
|
*
|
|
* Don't want main() to inline us and defeat the reason
|
|
* we have a separate function.
|
|
*/
|
|
static void ATTRIBUTE_NOINLINE
|
|
init(int argc, char *argv[])
|
|
{
|
|
int c, i;
|
|
int optF = 0;
|
|
|
|
if (!program_invocation_name || !*program_invocation_name) {
|
|
static char name[] = "strace";
|
|
program_invocation_name =
|
|
(argc > 0 && argv[0] && *argv[0]) ? argv[0] : name;
|
|
}
|
|
|
|
strace_tracer_pid = getpid();
|
|
|
|
os_release = get_os_release();
|
|
|
|
shared_log = stderr;
|
|
set_sortby(DEFAULT_SORTBY);
|
|
set_personality(DEFAULT_PERSONALITY);
|
|
qualify("trace=all");
|
|
qualify("abbrev=all");
|
|
qualify("verbose=all");
|
|
#if DEFAULT_QUAL_FLAGS != (QUAL_TRACE | QUAL_ABBREV | QUAL_VERBOSE)
|
|
# error Bug in DEFAULT_QUAL_FLAGS
|
|
#endif
|
|
qualify("signal=all");
|
|
while ((c = getopt(argc, argv, "+"
|
|
#ifdef ENABLE_STACKTRACE
|
|
"k"
|
|
#endif
|
|
"a:Ab:cCdDe:E:fFhiI:o:O:p:P:qrs:S:tTu:vVwxX:yz")) != EOF) {
|
|
switch (c) {
|
|
case 'a':
|
|
acolumn = string_to_uint(optarg);
|
|
if (acolumn < 0)
|
|
error_opt_arg(c, optarg);
|
|
break;
|
|
case 'A':
|
|
open_append = true;
|
|
break;
|
|
case 'b':
|
|
if (strcmp(optarg, "execve") != 0)
|
|
error_msg_and_die("Syscall '%s' for -b isn't supported",
|
|
optarg);
|
|
detach_on_execve = 1;
|
|
break;
|
|
case 'c':
|
|
if (cflag == CFLAG_BOTH) {
|
|
error_msg_and_help("-c and -C are mutually exclusive");
|
|
}
|
|
cflag = CFLAG_ONLY_STATS;
|
|
break;
|
|
case 'C':
|
|
if (cflag == CFLAG_ONLY_STATS) {
|
|
error_msg_and_help("-c and -C are mutually exclusive");
|
|
}
|
|
cflag = CFLAG_BOTH;
|
|
break;
|
|
case 'd':
|
|
debug_flag = 1;
|
|
break;
|
|
case 'D':
|
|
daemonized_tracer = 1;
|
|
break;
|
|
case 'e':
|
|
qualify(optarg);
|
|
break;
|
|
case 'E':
|
|
if (putenv(optarg) < 0)
|
|
perror_msg_and_die("putenv");
|
|
break;
|
|
case 'f':
|
|
followfork++;
|
|
break;
|
|
case 'F':
|
|
optF = 1;
|
|
break;
|
|
case 'h':
|
|
usage();
|
|
break;
|
|
case 'i':
|
|
iflag = 1;
|
|
break;
|
|
case 'I':
|
|
opt_intr = string_to_uint_upto(optarg, NUM_INTR_OPTS - 1);
|
|
if (opt_intr <= 0)
|
|
error_opt_arg(c, optarg);
|
|
break;
|
|
#ifdef ENABLE_STACKTRACE
|
|
case 'k':
|
|
stack_trace_enabled = true;
|
|
break;
|
|
#endif
|
|
case 'o':
|
|
outfname = optarg;
|
|
break;
|
|
case 'O':
|
|
i = string_to_uint(optarg);
|
|
if (i < 0)
|
|
error_opt_arg(c, optarg);
|
|
set_overhead(i);
|
|
break;
|
|
case 'p':
|
|
process_opt_p_list(optarg);
|
|
break;
|
|
case 'P':
|
|
pathtrace_select(optarg);
|
|
break;
|
|
case 'q':
|
|
qflag++;
|
|
break;
|
|
case 'r':
|
|
rflag = 1;
|
|
break;
|
|
case 's':
|
|
i = string_to_uint(optarg);
|
|
if (i < 0 || (unsigned int) i > -1U / 4)
|
|
error_opt_arg(c, optarg);
|
|
max_strlen = i;
|
|
break;
|
|
case 'S':
|
|
set_sortby(optarg);
|
|
break;
|
|
case 't':
|
|
tflag++;
|
|
break;
|
|
case 'T':
|
|
Tflag = 1;
|
|
break;
|
|
case 'u':
|
|
username = optarg;
|
|
break;
|
|
case 'v':
|
|
qualify("abbrev=none");
|
|
break;
|
|
case 'V':
|
|
print_version();
|
|
exit(0);
|
|
break;
|
|
case 'w':
|
|
count_wallclock = 1;
|
|
break;
|
|
case 'x':
|
|
xflag++;
|
|
break;
|
|
case 'X':
|
|
if (!strcmp(optarg, "raw"))
|
|
xlat_verbosity = XLAT_STYLE_RAW;
|
|
else if (!strcmp(optarg, "abbrev"))
|
|
xlat_verbosity = XLAT_STYLE_ABBREV;
|
|
else if (!strcmp(optarg, "verbose"))
|
|
xlat_verbosity = XLAT_STYLE_VERBOSE;
|
|
else
|
|
error_opt_arg(c, optarg);
|
|
break;
|
|
case 'y':
|
|
show_fd_path++;
|
|
break;
|
|
case 'z':
|
|
not_failing_only = 1;
|
|
break;
|
|
default:
|
|
error_msg_and_help(NULL);
|
|
break;
|
|
}
|
|
}
|
|
|
|
argv += optind;
|
|
argc -= optind;
|
|
|
|
if (argc < 0 || (!nprocs && !argc)) {
|
|
error_msg_and_help("must have PROG [ARGS] or -p PID");
|
|
}
|
|
|
|
if (!argc && daemonized_tracer) {
|
|
error_msg_and_help("PROG [ARGS] must be specified with -D");
|
|
}
|
|
|
|
if (optF) {
|
|
if (followfork) {
|
|
error_msg("deprecated option -F ignored");
|
|
} else {
|
|
error_msg("option -F is deprecated, "
|
|
"please use -f instead");
|
|
followfork = optF;
|
|
}
|
|
}
|
|
|
|
if (followfork >= 2 && cflag) {
|
|
error_msg_and_help("(-c or -C) and -ff are mutually exclusive");
|
|
}
|
|
|
|
if (count_wallclock && !cflag) {
|
|
error_msg_and_help("-w must be given with (-c or -C)");
|
|
}
|
|
|
|
if (cflag == CFLAG_ONLY_STATS) {
|
|
if (iflag)
|
|
error_msg("-%c has no effect with -c", 'i');
|
|
#ifdef ENABLE_STACKTRACE
|
|
if (stack_trace_enabled)
|
|
error_msg("-%c has no effect with -c", 'k');
|
|
#endif
|
|
if (rflag)
|
|
error_msg("-%c has no effect with -c", 'r');
|
|
if (tflag)
|
|
error_msg("-%c has no effect with -c", 't');
|
|
if (Tflag)
|
|
error_msg("-%c has no effect with -c", 'T');
|
|
if (show_fd_path)
|
|
error_msg("-%c has no effect with -c", 'y');
|
|
}
|
|
|
|
acolumn_spaces = xmalloc(acolumn + 1);
|
|
memset(acolumn_spaces, ' ', acolumn);
|
|
acolumn_spaces[acolumn] = '\0';
|
|
|
|
set_sighandler(SIGCHLD, SIG_DFL, ¶ms_for_tracee.child_sa);
|
|
|
|
#ifdef ENABLE_STACKTRACE
|
|
if (stack_trace_enabled)
|
|
unwind_init();
|
|
#endif
|
|
|
|
/* See if they want to run as another user. */
|
|
if (username != NULL) {
|
|
struct passwd *pent;
|
|
|
|
if (getuid() != 0 || geteuid() != 0) {
|
|
error_msg_and_die("You must be root to use the -u option");
|
|
}
|
|
pent = getpwnam(username);
|
|
if (pent == NULL) {
|
|
error_msg_and_die("Cannot find user '%s'", username);
|
|
}
|
|
run_uid = pent->pw_uid;
|
|
run_gid = pent->pw_gid;
|
|
} else {
|
|
run_uid = getuid();
|
|
run_gid = getgid();
|
|
}
|
|
|
|
if (followfork)
|
|
ptrace_setoptions |= PTRACE_O_TRACECLONE |
|
|
PTRACE_O_TRACEFORK |
|
|
PTRACE_O_TRACEVFORK;
|
|
debug_msg("ptrace_setoptions = %#x", ptrace_setoptions);
|
|
test_ptrace_seize();
|
|
|
|
/*
|
|
* NOMMU provides no forks necessary for PTRACE_GET_SYSCALL_INFO test,
|
|
* leave the default unchanged.
|
|
*/
|
|
if (!NOMMU_SYSTEM)
|
|
test_ptrace_get_syscall_info();
|
|
|
|
/*
|
|
* Is something weird with our stdin and/or stdout -
|
|
* for example, may they be not open? In this case,
|
|
* ensure that none of the future opens uses them.
|
|
*
|
|
* This was seen in the wild when /proc/sys/kernel/core_pattern
|
|
* was set to "|/bin/strace -o/tmp/LOG PROG":
|
|
* kernel runs coredump helper with fd#0 open but fd#1 closed (!),
|
|
* therefore LOG gets opened to fd#1, and fd#1 is closed by
|
|
* "don't hold up stdin/out open" code soon after.
|
|
*/
|
|
ensure_standard_fds_opened();
|
|
|
|
/* Check if they want to redirect the output. */
|
|
if (outfname) {
|
|
/* See if they want to pipe the output. */
|
|
if (outfname[0] == '|' || outfname[0] == '!') {
|
|
/*
|
|
* We can't do the <outfname>.PID funny business
|
|
* when using popen, so prohibit it.
|
|
*/
|
|
if (followfork >= 2)
|
|
error_msg_and_help("piping the output and -ff "
|
|
"are mutually exclusive");
|
|
shared_log = strace_popen(outfname + 1);
|
|
} else if (followfork < 2) {
|
|
shared_log = strace_fopen(outfname);
|
|
} else if (strlen(outfname) >= PATH_MAX - sizeof(int) * 3) {
|
|
errno = ENAMETOOLONG;
|
|
perror_msg_and_die("%s", outfname);
|
|
}
|
|
} else {
|
|
/* -ff without -o FILE is the same as single -f */
|
|
if (followfork >= 2)
|
|
followfork = 1;
|
|
}
|
|
|
|
if (!outfname || outfname[0] == '|' || outfname[0] == '!') {
|
|
setvbuf(shared_log, NULL, _IOLBF, 0);
|
|
}
|
|
|
|
/*
|
|
* argv[0] -pPID -oFILE Default interactive setting
|
|
* yes * 0 INTR_WHILE_WAIT
|
|
* no 1 0 INTR_WHILE_WAIT
|
|
* yes * 1 INTR_NEVER
|
|
* no 1 1 INTR_WHILE_WAIT
|
|
*/
|
|
|
|
if (outfname && argc) {
|
|
if (!opt_intr)
|
|
opt_intr = INTR_NEVER;
|
|
if (!qflag)
|
|
qflag = 1;
|
|
}
|
|
if (!opt_intr)
|
|
opt_intr = INTR_WHILE_WAIT;
|
|
|
|
/*
|
|
* startup_child() must be called before the signal handlers get
|
|
* installed below as they are inherited into the spawned process.
|
|
* Also we do not need to be protected by them as during interruption
|
|
* in the startup_child() mode we kill the spawned process anyway.
|
|
*/
|
|
if (argc) {
|
|
startup_child(argv);
|
|
}
|
|
|
|
set_sighandler(SIGTTOU, SIG_IGN, NULL);
|
|
set_sighandler(SIGTTIN, SIG_IGN, NULL);
|
|
if (opt_intr != INTR_ANYWHERE) {
|
|
if (opt_intr == INTR_BLOCK_TSTP_TOO)
|
|
set_sighandler(SIGTSTP, SIG_IGN, NULL);
|
|
/*
|
|
* In interactive mode (if no -o OUTFILE, or -p PID is used),
|
|
* fatal signals are handled asynchronously and acted
|
|
* when waiting for process state changes.
|
|
* In non-interactive mode these signals are ignored.
|
|
*/
|
|
set_sighandler(SIGHUP, interactive ? interrupt : SIG_IGN, NULL);
|
|
set_sighandler(SIGINT, interactive ? interrupt : SIG_IGN, NULL);
|
|
set_sighandler(SIGQUIT, interactive ? interrupt : SIG_IGN, NULL);
|
|
set_sighandler(SIGPIPE, interactive ? interrupt : SIG_IGN, NULL);
|
|
set_sighandler(SIGTERM, interactive ? interrupt : SIG_IGN, NULL);
|
|
}
|
|
|
|
sigemptyset(&timer_set);
|
|
sigaddset(&timer_set, SIGALRM);
|
|
sigprocmask(SIG_BLOCK, &timer_set, NULL);
|
|
set_sighandler(SIGALRM, timer_sighandler, NULL);
|
|
|
|
if (nprocs != 0 || daemonized_tracer)
|
|
startup_attach();
|
|
|
|
/* Do we want pids printed in our -o OUTFILE?
|
|
* -ff: no (every pid has its own file); or
|
|
* -f: yes (there can be more pids in the future); or
|
|
* -p PID1,PID2: yes (there are already more than one pid)
|
|
*/
|
|
print_pid_pfx = (outfname && followfork < 2 && (followfork == 1 || nprocs > 1));
|
|
}
|
|
|
|
static struct tcb *
|
|
pid2tcb(const int pid)
|
|
{
|
|
if (pid <= 0)
|
|
return NULL;
|
|
|
|
#define PID2TCB_CACHE_SIZE 1024U
|
|
#define PID2TCB_CACHE_MASK (PID2TCB_CACHE_SIZE - 1)
|
|
|
|
static struct tcb *pid2tcb_cache[PID2TCB_CACHE_SIZE];
|
|
struct tcb **const ptcp = &pid2tcb_cache[pid & PID2TCB_CACHE_MASK];
|
|
struct tcb *tcp = *ptcp;
|
|
|
|
if (tcp && tcp->pid == pid)
|
|
return tcp;
|
|
|
|
for (unsigned int i = 0; i < tcbtabsize; ++i) {
|
|
tcp = tcbtab[i];
|
|
if (tcp->pid == pid)
|
|
return *ptcp = tcp;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void
|
|
cleanup(void)
|
|
{
|
|
unsigned int i;
|
|
struct tcb *tcp;
|
|
int fatal_sig;
|
|
|
|
/* 'interrupted' is a volatile object, fetch it only once */
|
|
fatal_sig = interrupted;
|
|
if (!fatal_sig)
|
|
fatal_sig = SIGTERM;
|
|
|
|
for (i = 0; i < tcbtabsize; i++) {
|
|
tcp = tcbtab[i];
|
|
if (!tcp->pid)
|
|
continue;
|
|
debug_func_msg("looking at pid %u", tcp->pid);
|
|
if (tcp->pid == strace_child) {
|
|
kill(tcp->pid, SIGCONT);
|
|
kill(tcp->pid, fatal_sig);
|
|
}
|
|
detach(tcp);
|
|
}
|
|
if (cflag)
|
|
call_summary(shared_log);
|
|
}
|
|
|
|
static void
|
|
interrupt(int sig)
|
|
{
|
|
interrupted = sig;
|
|
}
|
|
|
|
static void
|
|
print_debug_info(const int pid, int status)
|
|
{
|
|
const unsigned int event = (unsigned int) status >> 16;
|
|
char buf[sizeof("WIFEXITED,exitcode=%u") + sizeof(int)*3 /*paranoia:*/ + 16];
|
|
char evbuf[sizeof(",EVENT_VFORK_DONE (%u)") + sizeof(int)*3 /*paranoia:*/ + 16];
|
|
|
|
strcpy(buf, "???");
|
|
if (WIFSIGNALED(status))
|
|
#ifdef WCOREDUMP
|
|
xsprintf(buf, "WIFSIGNALED,%ssig=%s",
|
|
WCOREDUMP(status) ? "core," : "",
|
|
signame(WTERMSIG(status)));
|
|
#else
|
|
xsprintf(buf, "WIFSIGNALED,sig=%s",
|
|
signame(WTERMSIG(status)));
|
|
#endif
|
|
if (WIFEXITED(status))
|
|
xsprintf(buf, "WIFEXITED,exitcode=%u", WEXITSTATUS(status));
|
|
if (WIFSTOPPED(status))
|
|
xsprintf(buf, "WIFSTOPPED,sig=%s", signame(WSTOPSIG(status)));
|
|
evbuf[0] = '\0';
|
|
if (event != 0) {
|
|
static const char *const event_names[] = {
|
|
[PTRACE_EVENT_CLONE] = "CLONE",
|
|
[PTRACE_EVENT_FORK] = "FORK",
|
|
[PTRACE_EVENT_VFORK] = "VFORK",
|
|
[PTRACE_EVENT_VFORK_DONE] = "VFORK_DONE",
|
|
[PTRACE_EVENT_EXEC] = "EXEC",
|
|
[PTRACE_EVENT_EXIT] = "EXIT",
|
|
/* [PTRACE_EVENT_STOP (=128)] would make biggish array */
|
|
};
|
|
const char *e = "??";
|
|
if (event < ARRAY_SIZE(event_names))
|
|
e = event_names[event];
|
|
else if (event == PTRACE_EVENT_STOP)
|
|
e = "STOP";
|
|
xsprintf(evbuf, ",EVENT_%s (%u)", e, event);
|
|
}
|
|
error_msg("[wait(0x%06x) = %u] %s%s", status, pid, buf, evbuf);
|
|
}
|
|
|
|
static struct tcb *
|
|
maybe_allocate_tcb(const int pid, int status)
|
|
{
|
|
if (!WIFSTOPPED(status)) {
|
|
if (detach_on_execve && pid == strace_child) {
|
|
/* example: strace -bexecve sh -c 'exec true' */
|
|
strace_child = 0;
|
|
return NULL;
|
|
}
|
|
/*
|
|
* This can happen if we inherited an unknown child.
|
|
* Example: (sleep 1 & exec strace true)
|
|
*/
|
|
error_msg("Exit of unknown pid %u ignored", pid);
|
|
return NULL;
|
|
}
|
|
if (followfork) {
|
|
/* We assume it's a fork/vfork/clone child */
|
|
struct tcb *tcp = alloctcb(pid);
|
|
after_successful_attach(tcp, post_attach_sigstop);
|
|
if (!qflag)
|
|
error_msg("Process %d attached", pid);
|
|
return tcp;
|
|
} else {
|
|
/*
|
|
* This can happen if a clone call misused CLONE_PTRACE itself.
|
|
*
|
|
* There used to be a dance around possible re-injection of
|
|
* WSTOPSIG(status), but it was later removed as the only
|
|
* observable stop here is the initial ptrace-stop.
|
|
*/
|
|
ptrace(PTRACE_DETACH, pid, NULL, 0L);
|
|
error_msg("Detached unknown pid %d", pid);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
static struct tcb *
|
|
maybe_switch_tcbs(struct tcb *tcp, const int pid)
|
|
{
|
|
FILE *fp;
|
|
struct tcb *execve_thread;
|
|
long old_pid = 0;
|
|
|
|
if (ptrace(PTRACE_GETEVENTMSG, pid, NULL, &old_pid) < 0)
|
|
return tcp;
|
|
/* Avoid truncation in pid2tcb() param passing */
|
|
if (old_pid <= 0 || old_pid == pid)
|
|
return tcp;
|
|
if ((unsigned long) old_pid > UINT_MAX)
|
|
return tcp;
|
|
execve_thread = pid2tcb(old_pid);
|
|
/* It should be !NULL, but I feel paranoid */
|
|
if (!execve_thread)
|
|
return tcp;
|
|
|
|
if (execve_thread->curcol != 0) {
|
|
/*
|
|
* One case we are here is -ff:
|
|
* try "strace -oLOG -ff test/threaded_execve"
|
|
*/
|
|
fprintf(execve_thread->outf, " <pid changed to %d ...>\n", pid);
|
|
/*execve_thread->curcol = 0; - no need, see code below */
|
|
}
|
|
/* Swap output FILEs (needed for -ff) */
|
|
fp = execve_thread->outf;
|
|
execve_thread->outf = tcp->outf;
|
|
tcp->outf = fp;
|
|
/* And their column positions */
|
|
execve_thread->curcol = tcp->curcol;
|
|
tcp->curcol = 0;
|
|
/* Drop leader, but close execve'd thread outfile (if -ff) */
|
|
droptcb(tcp);
|
|
/* Switch to the thread, reusing leader's outfile and pid */
|
|
tcp = execve_thread;
|
|
tcp->pid = pid;
|
|
if (cflag != CFLAG_ONLY_STATS) {
|
|
printleader(tcp);
|
|
tprintf("+++ superseded by execve in pid %lu +++\n", old_pid);
|
|
line_ended();
|
|
tcp->flags |= TCB_REPRINT;
|
|
}
|
|
|
|
return tcp;
|
|
}
|
|
|
|
static void
|
|
print_signalled(struct tcb *tcp, const int pid, int status)
|
|
{
|
|
if (pid == strace_child) {
|
|
exit_code = 0x100 | WTERMSIG(status);
|
|
strace_child = 0;
|
|
}
|
|
|
|
if (cflag != CFLAG_ONLY_STATS
|
|
&& is_number_in_set(WTERMSIG(status), signal_set)) {
|
|
printleader(tcp);
|
|
#ifdef WCOREDUMP
|
|
tprintf("+++ killed by %s %s+++\n",
|
|
signame(WTERMSIG(status)),
|
|
WCOREDUMP(status) ? "(core dumped) " : "");
|
|
#else
|
|
tprintf("+++ killed by %s +++\n",
|
|
signame(WTERMSIG(status)));
|
|
#endif
|
|
line_ended();
|
|
}
|
|
}
|
|
|
|
static void
|
|
print_exited(struct tcb *tcp, const int pid, int status)
|
|
{
|
|
if (pid == strace_child) {
|
|
exit_code = WEXITSTATUS(status);
|
|
strace_child = 0;
|
|
}
|
|
|
|
if (cflag != CFLAG_ONLY_STATS &&
|
|
qflag < 2) {
|
|
printleader(tcp);
|
|
tprintf("+++ exited with %d +++\n", WEXITSTATUS(status));
|
|
line_ended();
|
|
}
|
|
}
|
|
|
|
static void
|
|
print_stopped(struct tcb *tcp, const siginfo_t *si, const unsigned int sig)
|
|
{
|
|
if (cflag != CFLAG_ONLY_STATS
|
|
&& !hide_log(tcp)
|
|
&& is_number_in_set(sig, signal_set)) {
|
|
printleader(tcp);
|
|
if (si) {
|
|
tprintf("--- %s ", signame(sig));
|
|
printsiginfo(si);
|
|
tprints(" ---\n");
|
|
} else
|
|
tprintf("--- stopped by %s ---\n", signame(sig));
|
|
line_ended();
|
|
|
|
#ifdef ENABLE_STACKTRACE
|
|
if (stack_trace_enabled)
|
|
unwind_tcb_print(tcp);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
static void
|
|
startup_tcb(struct tcb *tcp)
|
|
{
|
|
debug_msg("pid %d has TCB_STARTUP, initializing it", tcp->pid);
|
|
|
|
tcp->flags &= ~TCB_STARTUP;
|
|
|
|
if (!use_seize) {
|
|
debug_msg("setting opts 0x%x on pid %d",
|
|
ptrace_setoptions, tcp->pid);
|
|
if (ptrace(PTRACE_SETOPTIONS, tcp->pid, NULL, ptrace_setoptions) < 0) {
|
|
if (errno != ESRCH) {
|
|
/* Should never happen, really */
|
|
perror_msg_and_die("PTRACE_SETOPTIONS");
|
|
}
|
|
}
|
|
}
|
|
|
|
if ((tcp->flags & TCB_GRABBED) && (get_scno(tcp) == 1))
|
|
tcp->s_prev_ent = tcp->s_ent;
|
|
}
|
|
|
|
static void
|
|
print_event_exit(struct tcb *tcp)
|
|
{
|
|
if (entering(tcp) || filtered(tcp) || hide_log(tcp)
|
|
|| cflag == CFLAG_ONLY_STATS) {
|
|
return;
|
|
}
|
|
|
|
if (followfork < 2 && printing_tcp && printing_tcp != tcp
|
|
&& printing_tcp->curcol != 0) {
|
|
set_current_tcp(printing_tcp);
|
|
tprints(" <unfinished ...>\n");
|
|
flush_tcp_output(printing_tcp);
|
|
printing_tcp->curcol = 0;
|
|
set_current_tcp(tcp);
|
|
}
|
|
|
|
if ((followfork < 2 && printing_tcp != tcp)
|
|
|| (tcp->flags & TCB_REPRINT)) {
|
|
tcp->flags &= ~TCB_REPRINT;
|
|
printleader(tcp);
|
|
tprintf("<... %s resumed>", tcp->s_ent->sys_name);
|
|
}
|
|
|
|
if (!(tcp->sys_func_rval & RVAL_DECODED)) {
|
|
/*
|
|
* The decoder has probably decided to print something
|
|
* on exiting syscall which is not going to happen.
|
|
*/
|
|
tprints(" <unfinished ...>");
|
|
}
|
|
|
|
printing_tcp = tcp;
|
|
tprints(") ");
|
|
tabto();
|
|
tprints("= ?\n");
|
|
line_ended();
|
|
}
|
|
|
|
static const struct tcb_wait_data *
|
|
next_event(void)
|
|
{
|
|
static struct tcb_wait_data wait_data;
|
|
|
|
int pid;
|
|
int status;
|
|
struct tcb *tcp;
|
|
struct tcb_wait_data *wd = &wait_data;
|
|
struct rusage ru;
|
|
|
|
if (interrupted)
|
|
return NULL;
|
|
|
|
/*
|
|
* Used to exit simply when nprocs hits zero, but in this testcase:
|
|
* int main(void) { _exit(!!fork()); }
|
|
* under strace -f, parent sometimes (rarely) manages
|
|
* to exit before we see the first stop of the child,
|
|
* and we are losing track of it:
|
|
* 19923 clone(...) = 19924
|
|
* 19923 exit_group(1) = ?
|
|
* 19923 +++ exited with 1 +++
|
|
* Exiting only when wait() returns ECHILD works better.
|
|
*/
|
|
if (popen_pid != 0) {
|
|
/* However, if -o|logger is in use, we can't do that.
|
|
* Can work around that by double-forking the logger,
|
|
* but that loses the ability to wait for its completion
|
|
* on exit. Oh well...
|
|
*/
|
|
if (nprocs == 0)
|
|
return NULL;
|
|
}
|
|
|
|
const bool unblock_delay_timer = is_delay_timer_armed();
|
|
|
|
/*
|
|
* The window of opportunity to handle expirations
|
|
* of the delay timer opens here.
|
|
*
|
|
* Unblock the signal handler for the delay timer
|
|
* iff the delay timer is already created.
|
|
*/
|
|
if (unblock_delay_timer)
|
|
sigprocmask(SIG_UNBLOCK, &timer_set, NULL);
|
|
|
|
/*
|
|
* If the delay timer has expired, then its expiration
|
|
* has been handled already by the signal handler.
|
|
*
|
|
* If the delay timer expires during wait4(),
|
|
* then the system call will be interrupted and
|
|
* the expiration will be handled by the signal handler.
|
|
*/
|
|
pid = wait4(-1, &status, __WALL, (cflag ? &ru : NULL));
|
|
const int wait_errno = errno;
|
|
|
|
/*
|
|
* The window of opportunity to handle expirations
|
|
* of the delay timer closes here.
|
|
*
|
|
* Block the signal handler for the delay timer
|
|
* iff it was unblocked earlier.
|
|
*/
|
|
if (unblock_delay_timer) {
|
|
sigprocmask(SIG_BLOCK, &timer_set, NULL);
|
|
|
|
if (restart_failed)
|
|
return NULL;
|
|
}
|
|
|
|
if (pid < 0) {
|
|
if (wait_errno == EINTR) {
|
|
wd->te = TE_NEXT;
|
|
return wd;
|
|
}
|
|
if (nprocs == 0 && wait_errno == ECHILD)
|
|
return NULL;
|
|
/*
|
|
* If nprocs > 0, ECHILD is not expected,
|
|
* treat it as any other error here:
|
|
*/
|
|
errno = wait_errno;
|
|
perror_msg_and_die("wait4(__WALL)");
|
|
}
|
|
|
|
wd->status = status;
|
|
|
|
if (pid == popen_pid) {
|
|
if (!WIFSTOPPED(status))
|
|
popen_pid = 0;
|
|
wd->te = TE_NEXT;
|
|
return wd;
|
|
}
|
|
|
|
if (debug_flag)
|
|
print_debug_info(pid, status);
|
|
|
|
/* Look up 'pid' in our table. */
|
|
tcp = pid2tcb(pid);
|
|
|
|
if (!tcp) {
|
|
tcp = maybe_allocate_tcb(pid, status);
|
|
if (!tcp) {
|
|
wd->te = TE_NEXT;
|
|
return wd;
|
|
}
|
|
}
|
|
|
|
clear_regs(tcp);
|
|
|
|
/* Set current output file */
|
|
set_current_tcp(tcp);
|
|
|
|
if (cflag) {
|
|
struct timespec stime = {
|
|
.tv_sec = ru.ru_stime.tv_sec,
|
|
.tv_nsec = ru.ru_stime.tv_usec * 1000
|
|
};
|
|
ts_sub(&tcp->dtime, &stime, &tcp->stime);
|
|
tcp->stime = stime;
|
|
}
|
|
|
|
if (WIFSIGNALED(status)) {
|
|
wd->te = TE_SIGNALLED;
|
|
return wd;
|
|
}
|
|
|
|
if (WIFEXITED(status)) {
|
|
wd->te = TE_EXITED;
|
|
return wd;
|
|
}
|
|
|
|
/*
|
|
* As WCONTINUED flag has not been specified to wait4,
|
|
* it cannot be WIFCONTINUED(status), so the only case
|
|
* that remains is WIFSTOPPED(status).
|
|
*/
|
|
|
|
/* Is this the very first time we see this tracee stopped? */
|
|
if (tcp->flags & TCB_STARTUP)
|
|
startup_tcb(tcp);
|
|
|
|
const unsigned int sig = WSTOPSIG(status);
|
|
const unsigned int event = (unsigned int) status >> 16;
|
|
|
|
switch (event) {
|
|
case 0:
|
|
/*
|
|
* Is this post-attach SIGSTOP?
|
|
* Interestingly, the process may stop
|
|
* with STOPSIG equal to some other signal
|
|
* than SIGSTOP if we happened to attach
|
|
* just before the process takes a signal.
|
|
*/
|
|
if (sig == SIGSTOP && (tcp->flags & TCB_IGNORE_ONE_SIGSTOP)) {
|
|
debug_func_msg("ignored SIGSTOP on pid %d", tcp->pid);
|
|
tcp->flags &= ~TCB_IGNORE_ONE_SIGSTOP;
|
|
wd->te = TE_RESTART;
|
|
} else if (sig == syscall_trap_sig) {
|
|
wd->te = TE_SYSCALL_STOP;
|
|
} else {
|
|
memset(&wd->si, 0, sizeof(wd->si));
|
|
/*
|
|
* True if tracee is stopped by signal
|
|
* (as opposed to "tracee received signal").
|
|
* TODO: shouldn't we check for errno == EINVAL too?
|
|
* We can get ESRCH instead, you know...
|
|
*/
|
|
bool stopped = ptrace(PTRACE_GETSIGINFO, pid, 0, &wd->si) < 0;
|
|
wd->te = stopped ? TE_GROUP_STOP : TE_SIGNAL_DELIVERY_STOP;
|
|
}
|
|
break;
|
|
case PTRACE_EVENT_STOP:
|
|
/*
|
|
* PTRACE_INTERRUPT-stop or group-stop.
|
|
* PTRACE_INTERRUPT-stop has sig == SIGTRAP here.
|
|
*/
|
|
switch (sig) {
|
|
case SIGSTOP:
|
|
case SIGTSTP:
|
|
case SIGTTIN:
|
|
case SIGTTOU:
|
|
wd->te = TE_GROUP_STOP;
|
|
break;
|
|
default:
|
|
wd->te = TE_RESTART;
|
|
}
|
|
break;
|
|
case PTRACE_EVENT_EXEC:
|
|
wd->te = TE_STOP_BEFORE_EXECVE;
|
|
break;
|
|
case PTRACE_EVENT_EXIT:
|
|
wd->te = TE_STOP_BEFORE_EXIT;
|
|
break;
|
|
default:
|
|
wd->te = TE_RESTART;
|
|
}
|
|
|
|
return wd;
|
|
}
|
|
|
|
static int
|
|
trace_syscall(struct tcb *tcp, unsigned int *sig)
|
|
{
|
|
if (entering(tcp)) {
|
|
int res = syscall_entering_decode(tcp);
|
|
switch (res) {
|
|
case 0:
|
|
return 0;
|
|
case 1:
|
|
res = syscall_entering_trace(tcp, sig);
|
|
}
|
|
syscall_entering_finish(tcp, res);
|
|
return res;
|
|
} else {
|
|
struct timespec ts = {};
|
|
int res = syscall_exiting_decode(tcp, &ts);
|
|
if (res != 0) {
|
|
res = syscall_exiting_trace(tcp, &ts, res);
|
|
}
|
|
syscall_exiting_finish(tcp);
|
|
return res;
|
|
}
|
|
}
|
|
|
|
/* Returns true iff the main trace loop has to continue. */
|
|
static bool
|
|
dispatch_event(const struct tcb_wait_data *wd)
|
|
{
|
|
unsigned int restart_op = PTRACE_SYSCALL;
|
|
unsigned int restart_sig = 0;
|
|
enum trace_event te = wd ? wd->te : TE_BREAK;
|
|
/*
|
|
* Copy wd->status to a non-const variable to workaround glibc bugs
|
|
* around union wait fixed by glibc commit glibc-2.24~391
|
|
*/
|
|
int status = wd ? wd->status : 0;
|
|
|
|
switch (te) {
|
|
case TE_BREAK:
|
|
return false;
|
|
|
|
case TE_NEXT:
|
|
return true;
|
|
|
|
case TE_RESTART:
|
|
break;
|
|
|
|
case TE_SYSCALL_STOP:
|
|
if (trace_syscall(current_tcp, &restart_sig) < 0) {
|
|
/*
|
|
* ptrace() failed in trace_syscall().
|
|
* Likely a result of process disappearing mid-flight.
|
|
* Observed case: exit_group() or SIGKILL terminating
|
|
* all processes in thread group.
|
|
* We assume that ptrace error was caused by process death.
|
|
* We used to detach(current_tcp) here, but since we no
|
|
* longer implement "detach before death" policy/hack,
|
|
* we can let this process to report its death to us
|
|
* normally, via WIFEXITED or WIFSIGNALED wait status.
|
|
*/
|
|
return true;
|
|
}
|
|
break;
|
|
|
|
case TE_SIGNAL_DELIVERY_STOP:
|
|
restart_sig = WSTOPSIG(status);
|
|
print_stopped(current_tcp, &wd->si, restart_sig);
|
|
break;
|
|
|
|
case TE_SIGNALLED:
|
|
print_signalled(current_tcp, current_tcp->pid, status);
|
|
droptcb(current_tcp);
|
|
return true;
|
|
|
|
case TE_GROUP_STOP:
|
|
restart_sig = WSTOPSIG(status);
|
|
print_stopped(current_tcp, NULL, restart_sig);
|
|
if (use_seize) {
|
|
/*
|
|
* This ends ptrace-stop, but does *not* end group-stop.
|
|
* This makes stopping signals work properly on straced
|
|
* process (that is, process really stops. It used to
|
|
* continue to run).
|
|
*/
|
|
restart_op = PTRACE_LISTEN;
|
|
restart_sig = 0;
|
|
}
|
|
break;
|
|
|
|
case TE_EXITED:
|
|
print_exited(current_tcp, current_tcp->pid, status);
|
|
droptcb(current_tcp);
|
|
return true;
|
|
|
|
case TE_STOP_BEFORE_EXECVE:
|
|
/* The syscall succeeded, clear the flag. */
|
|
current_tcp->flags &= ~TCB_CHECK_EXEC_SYSCALL;
|
|
/*
|
|
* Check that we are inside syscall now (next event after
|
|
* PTRACE_EVENT_EXEC should be for syscall exiting). If it is
|
|
* not the case, we might have a situation when we attach to a
|
|
* process and the first thing we see is a PTRACE_EVENT_EXEC
|
|
* and all the following syscall state tracking is screwed up
|
|
* otherwise.
|
|
*/
|
|
if (entering(current_tcp)) {
|
|
int ret;
|
|
|
|
error_msg("Stray PTRACE_EVENT_EXEC from pid %d"
|
|
", trying to recover...",
|
|
current_tcp->pid);
|
|
|
|
current_tcp->flags |= TCB_RECOVERING;
|
|
ret = trace_syscall(current_tcp, &restart_sig);
|
|
current_tcp->flags &= ~TCB_RECOVERING;
|
|
|
|
if (ret < 0) {
|
|
/* The reason is described in TE_SYSCALL_STOP */
|
|
return true;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Under Linux, execve changes pid to thread leader's pid,
|
|
* and we see this changed pid on EVENT_EXEC and later,
|
|
* execve sysexit. Leader "disappears" without exit
|
|
* notification. Let user know that, drop leader's tcb,
|
|
* and fix up pid in execve thread's tcb.
|
|
* Effectively, execve thread's tcb replaces leader's tcb.
|
|
*
|
|
* BTW, leader is 'stuck undead' (doesn't report WIFEXITED
|
|
* on exit syscall) in multithreaded programs exactly
|
|
* in order to handle this case.
|
|
*
|
|
* PTRACE_GETEVENTMSG returns old pid starting from Linux 3.0.
|
|
* On 2.6 and earlier, it can return garbage.
|
|
*/
|
|
if (os_release >= KERNEL_VERSION(3, 0, 0))
|
|
set_current_tcp(maybe_switch_tcbs(current_tcp,
|
|
current_tcp->pid));
|
|
|
|
if (detach_on_execve) {
|
|
if (current_tcp->flags & TCB_SKIP_DETACH_ON_FIRST_EXEC) {
|
|
current_tcp->flags &= ~TCB_SKIP_DETACH_ON_FIRST_EXEC;
|
|
} else {
|
|
detach(current_tcp); /* do "-b execve" thingy */
|
|
return true;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case TE_STOP_BEFORE_EXIT:
|
|
print_event_exit(current_tcp);
|
|
break;
|
|
}
|
|
|
|
/* We handled quick cases, we are permitted to interrupt now. */
|
|
if (interrupted)
|
|
return false;
|
|
|
|
/* If the process is being delayed, do not ptrace_restart just yet */
|
|
if (syscall_delayed(current_tcp))
|
|
return true;
|
|
|
|
if (ptrace_restart(restart_op, current_tcp, restart_sig) < 0) {
|
|
/* Note: ptrace_restart emitted error message */
|
|
exit_code = 1;
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static bool
|
|
restart_delayed_tcb(struct tcb *const tcp)
|
|
{
|
|
const struct tcb_wait_data wd = { .te = TE_RESTART };
|
|
|
|
debug_func_msg("pid %d", tcp->pid);
|
|
|
|
tcp->flags &= ~TCB_DELAYED;
|
|
|
|
struct tcb *const prev_tcp = current_tcp;
|
|
current_tcp = tcp;
|
|
bool ret = dispatch_event(&wd);
|
|
current_tcp = prev_tcp;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static bool
|
|
restart_delayed_tcbs(void)
|
|
{
|
|
struct tcb *tcp_next = NULL;
|
|
struct timespec ts_now;
|
|
|
|
clock_gettime(CLOCK_MONOTONIC, &ts_now);
|
|
|
|
for (size_t i = 0; i < tcbtabsize; i++) {
|
|
struct tcb *tcp = tcbtab[i];
|
|
|
|
if (tcp->pid && syscall_delayed(tcp)) {
|
|
if (ts_cmp(&ts_now, &tcp->delay_expiration_time) > 0) {
|
|
if (!restart_delayed_tcb(tcp))
|
|
return false;
|
|
} else {
|
|
/* Check whether this tcb is the next. */
|
|
if (!tcp_next ||
|
|
ts_cmp(&tcp_next->delay_expiration_time,
|
|
&tcp->delay_expiration_time) > 0) {
|
|
tcp_next = tcp;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (tcp_next)
|
|
arm_delay_timer(tcp_next);
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* As this signal handler does a lot of work that is not suitable
|
|
* for signal handlers, extra care must be taken to ensure that
|
|
* it is enabled only in those places where it's safe.
|
|
*/
|
|
static void
|
|
timer_sighandler(int sig)
|
|
{
|
|
delay_timer_expired();
|
|
|
|
if (restart_failed)
|
|
return;
|
|
|
|
int saved_errno = errno;
|
|
|
|
if (!restart_delayed_tcbs())
|
|
restart_failed = 1;
|
|
|
|
errno = saved_errno;
|
|
}
|
|
|
|
#ifdef ENABLE_COVERAGE_GCOV
|
|
extern void __gcov_flush(void);
|
|
#endif
|
|
|
|
static void ATTRIBUTE_NORETURN
|
|
terminate(void)
|
|
{
|
|
cleanup();
|
|
fflush(NULL);
|
|
if (shared_log != stderr)
|
|
fclose(shared_log);
|
|
if (popen_pid) {
|
|
while (waitpid(popen_pid, NULL, 0) < 0 && errno == EINTR)
|
|
;
|
|
}
|
|
if (exit_code > 0xff) {
|
|
/* Avoid potential core file clobbering. */
|
|
struct_rlimit rlim = {0, 0};
|
|
set_rlimit(RLIMIT_CORE, &rlim);
|
|
|
|
/* Child was killed by a signal, mimic that. */
|
|
exit_code &= 0xff;
|
|
signal(exit_code, SIG_DFL);
|
|
#ifdef ENABLE_COVERAGE_GCOV
|
|
__gcov_flush();
|
|
#endif
|
|
raise(exit_code);
|
|
|
|
/* Unblock the signal. */
|
|
sigset_t mask;
|
|
sigemptyset(&mask);
|
|
sigaddset(&mask, exit_code);
|
|
#ifdef ENABLE_COVERAGE_GCOV
|
|
__gcov_flush();
|
|
#endif
|
|
sigprocmask(SIG_UNBLOCK, &mask, NULL);
|
|
|
|
/* Paranoia - what if this signal is not fatal?
|
|
Exit with 128 + signo then. */
|
|
exit_code += 128;
|
|
}
|
|
exit(exit_code);
|
|
}
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
setlocale(LC_ALL, "");
|
|
init(argc, argv);
|
|
|
|
exit_code = !nprocs;
|
|
|
|
while (dispatch_event(next_event()))
|
|
;
|
|
terminate();
|
|
}
|