blob: ff5d0a7e9d1959bd695d3ad89238f808696da8f7 [file] [log] [blame]
/*
*
* honggfuzz - routines dealing with subprocesses
* -----------------------------------------
*
* Author: Robert Swiecki <swiecki@google.com>
* Felix Gröbert <groebert@google.com>
*
* Copyright 2010-2018 by Google Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License. You may obtain
* a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied. See the License for the specific language governing
* permissions and limitations under the License.
*
*/
#include "subproc.h"
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "arch.h"
#include "fuzz.h"
#include "libhfcommon/common.h"
#include "libhfcommon/files.h"
#include "libhfcommon/log.h"
#include "libhfcommon/util.h"
extern char** environ;
const char* subproc_StatusToStr(int status, char* str, size_t len) {
if (WIFEXITED(status)) {
snprintf(str, len, "EXITED, exit code: %d", WEXITSTATUS(status));
return str;
}
if (WIFSIGNALED(status)) {
snprintf(
str, len, "SIGNALED, signal: %d (%s)", WTERMSIG(status), strsignal(WTERMSIG(status)));
return str;
}
if (WIFCONTINUED(status)) {
snprintf(str, len, "CONTINUED");
return str;
}
if (!WIFSTOPPED(status)) {
snprintf(str, len, "UNKNOWN STATUS: %d", status);
return str;
}
/* Must be in a stopped state */
if (WSTOPSIG(status) == (SIGTRAP | 0x80)) {
snprintf(str, len, "STOPPED (linux syscall): %d (%s)", WSTOPSIG(status),
strsignal(WSTOPSIG(status)));
return str;
}
#if defined(PTRACE_EVENT_STOP)
#define __LINUX_WPTRACEEVENT(x) ((x & 0xff0000) >> 16)
if (WSTOPSIG(status) == SIGTRAP && __LINUX_WPTRACEEVENT(status) != 0) {
switch (__LINUX_WPTRACEEVENT(status)) {
case PTRACE_EVENT_FORK:
snprintf(str, len, "EVENT (Linux) - fork - with signal: %d (%s)", WSTOPSIG(status),
strsignal(WSTOPSIG(status)));
return str;
case PTRACE_EVENT_VFORK:
snprintf(str, len, "EVENT (Linux) - vfork - with signal: %d (%s)", WSTOPSIG(status),
strsignal(WSTOPSIG(status)));
return str;
case PTRACE_EVENT_CLONE:
snprintf(str, len, "EVENT (Linux) - clone - with signal: %d (%s)", WSTOPSIG(status),
strsignal(WSTOPSIG(status)));
return str;
case PTRACE_EVENT_EXEC:
snprintf(str, len, "EVENT (Linux) - exec - with signal: %d (%s)", WSTOPSIG(status),
strsignal(WSTOPSIG(status)));
return str;
case PTRACE_EVENT_VFORK_DONE:
snprintf(str, len, "EVENT (Linux) - vfork_done - with signal: %d (%s)",
WSTOPSIG(status), strsignal(WSTOPSIG(status)));
return str;
case PTRACE_EVENT_EXIT:
snprintf(str, len, "EVENT (Linux) - exit - with signal: %d (%s)", WSTOPSIG(status),
strsignal(WSTOPSIG(status)));
return str;
case PTRACE_EVENT_SECCOMP:
snprintf(str, len, "EVENT (Linux) - seccomp - with signal: %d (%s)",
WSTOPSIG(status), strsignal(WSTOPSIG(status)));
return str;
case PTRACE_EVENT_STOP:
snprintf(str, len, "EVENT (Linux) - stop - with signal: %d (%s)", WSTOPSIG(status),
strsignal(WSTOPSIG(status)));
return str;
default:
snprintf(str, len, "EVENT (Linux) UNKNOWN (%d): with signal: %d (%s)",
__LINUX_WPTRACEEVENT(status), WSTOPSIG(status), strsignal(WSTOPSIG(status)));
return str;
}
}
#endif /* defined(PTRACE_EVENT_STOP) */
snprintf(
str, len, "STOPPED with signal: %d (%s)", WSTOPSIG(status), strsignal(WSTOPSIG(status)));
return str;
}
static bool subproc_persistentSendFileIndicator(run_t* run) {
uint64_t len = (uint64_t)run->dynamicFileSz;
if (!files_sendToSocketNB(run->persistentSock, (uint8_t*)&len, sizeof(len))) {
PLOG_W("files_sendToSocketNB(len=%zu)", sizeof(len));
return false;
}
return true;
}
static bool subproc_persistentGetReady(run_t* run) {
uint8_t rcv;
if (recv(run->persistentSock, &rcv, sizeof(rcv), MSG_DONTWAIT) != sizeof(rcv)) {
return false;
}
if (rcv != HFReadyTag) {
LOG_E("Received invalid message from the persistent process: '%c' (0x%" PRIx8
") , expected '%c' (0x%" PRIx8 ")",
rcv, rcv, HFReadyTag, HFReadyTag);
return false;
}
return true;
}
bool subproc_persistentModeStateMachine(run_t* run) {
if (!run->global->exe.persistent) {
return false;
}
for (;;) {
switch (run->runState) {
case _HF_RS_WAITING_FOR_INITIAL_READY: {
if (!subproc_persistentGetReady(run)) {
return false;
}
run->runState = _HF_RS_SEND_DATA;
}; break;
case _HF_RS_SEND_DATA: {
if (!subproc_persistentSendFileIndicator(run)) {
LOG_E("Could not send the file size indicator to the persistent process. "
"Killing the process pid=%d",
(int)run->pid);
kill(run->pid, SIGKILL);
return false;
}
run->runState = _HF_RS_WAITING_FOR_READY;
}; break;
case _HF_RS_WAITING_FOR_READY: {
if (!subproc_persistentGetReady(run)) {
return false;
}
run->runState = _HF_RS_SEND_DATA;
/* The current persistent round is done */
return true;
}; break;
default: {
LOG_F("Unknown runState: %d", run->runState);
}; break;
}
}
}
static bool subproc_PrepareExecv(run_t* run) {
/*
* The address space limit. If big enough - roughly the size of RAM used
*/
#ifdef RLIMIT_AS
if (run->global->exe.asLimit) {
const struct rlimit rl = {
.rlim_cur = run->global->exe.asLimit * 1024ULL * 1024ULL,
.rlim_max = run->global->exe.asLimit * 1024ULL * 1024ULL,
};
if (setrlimit(RLIMIT_AS, &rl) == -1) {
PLOG_W("Couldn't enforce the RLIMIT_AS resource limit, ignoring");
}
}
#endif /* ifdef RLIMIT_AS */
#ifdef RLIMIT_RSS
if (run->global->exe.rssLimit) {
const struct rlimit rl = {
.rlim_cur = run->global->exe.rssLimit * 1024ULL * 1024ULL,
.rlim_max = run->global->exe.rssLimit * 1024ULL * 1024ULL,
};
if (setrlimit(RLIMIT_RSS, &rl) == -1) {
PLOG_W("Couldn't enforce the RLIMIT_RSS resource limit, ignoring");
}
}
#endif /* ifdef RLIMIT_RSS */
#ifdef RLIMIT_DATA
if (run->global->exe.dataLimit) {
const struct rlimit rl = {
.rlim_cur = run->global->exe.dataLimit * 1024ULL * 1024ULL,
.rlim_max = run->global->exe.dataLimit * 1024ULL * 1024ULL,
};
if (setrlimit(RLIMIT_DATA, &rl) == -1) {
PLOG_W("Couldn't enforce the RLIMIT_DATA resource limit, ignoring");
}
}
#endif /* ifdef RLIMIT_DATA */
#ifdef RLIMIT_CORE
const struct rlimit rl = {
.rlim_cur = run->global->exe.coreLimit * 1024ULL * 1024ULL,
.rlim_max = run->global->exe.coreLimit * 1024ULL * 1024ULL,
};
if (setrlimit(RLIMIT_CORE, &rl) == -1) {
PLOG_W("Couldn't enforce the RLIMIT_CORE resource limit, ignoring");
}
#endif /* ifdef RLIMIT_CORE */
if (run->global->exe.clearEnv) {
environ = NULL;
}
for (size_t i = 0; i < ARRAYSIZE(run->global->exe.envs) && run->global->exe.envs[i]; i++) {
putenv(run->global->exe.envs[i]);
}
char fuzzNo[128];
snprintf(fuzzNo, sizeof(fuzzNo), "%" PRId32, run->fuzzNo);
setenv(_HF_THREAD_NO_ENV, fuzzNo, 1);
if (run->global->exe.netDriver) {
setenv(_HF_THREAD_NETDRIVER_ENV, "1", 1);
}
/* Make sure it's a new process group / session, so waitpid can wait for -(run->pid) */
setsid();
util_closeStdio(/* close_stdin= */ run->global->exe.nullifyStdio,
/* close_stdout= */ run->global->exe.nullifyStdio,
/* close_stderr= */ run->global->exe.nullifyStdio);
/* The bitmap structure */
if (run->global->feedback.bbFd != -1 && dup2(run->global->feedback.bbFd, _HF_BITMAP_FD) == -1) {
PLOG_E("dup2(%d, _HF_BITMAP_FD=%d)", run->global->feedback.bbFd, _HF_BITMAP_FD);
return false;
}
/* The input file to _HF_INPUT_FD */
if (run->global->exe.persistent && dup2(run->dynamicFileFd, _HF_INPUT_FD) == -1) {
PLOG_E("dup2('%d', _HF_INPUT_FD='%d')", run->dynamicFileFd, _HF_INPUT_FD);
return false;
}
/* The log FD */
if ((run->global->exe.netDriver || run->global->exe.persistent)) {
if (dup2(logFd(), _HF_LOG_FD) == -1) {
PLOG_E("dup2(%d, _HF_LOG_FD=%d)", logFd(), _HF_LOG_FD);
return false;
}
char llstr[32];
snprintf(llstr, sizeof(llstr), "%d", logGetLevel());
setenv(_HF_LOG_LEVEL_ENV, llstr, 1);
}
sigset_t sset;
sigemptyset(&sset);
if (sigprocmask(SIG_SETMASK, &sset, NULL) == -1) {
PLOG_W("sigprocmask(empty_set)");
}
if (!run->global->exe.persistent) {
if ((run->dynamicFileCopyFd = files_writeBufToTmpFile(
run->global->io.workDir, run->dynamicFile, run->dynamicFileSz, 0)) == -1) {
LOG_E("Couldn't save data to a temporary file");
return false;
}
if (run->global->exe.fuzzStdin && dup2(run->dynamicFileCopyFd, STDIN_FILENO) == -1) {
PLOG_E("dup2(_HF_INPUT_FD=%d, STDIN_FILENO=%d)", run->dynamicFileCopyFd, STDIN_FILENO);
return false;
}
}
return true;
}
static bool subproc_New(run_t* run) {
if (run->pid) {
return true;
}
int sv[2];
if (run->global->exe.persistent) {
if (run->persistentSock != -1) {
close(run->persistentSock);
}
int sock_type = SOCK_STREAM;
#if defined(SOCK_CLOEXEC)
sock_type |= SOCK_CLOEXEC;
#endif
if (socketpair(AF_UNIX, sock_type, 0, sv) == -1) {
PLOG_W("socketpair(AF_UNIX, SOCK_STREAM, 0, sv)");
return false;
}
run->persistentSock = sv[0];
}
LOG_D("Forking new process for thread: %" PRId32, run->fuzzNo);
run->pid = arch_fork(run);
if (run->pid == -1) {
PLOG_E("Couldn't fork");
run->pid = 0;
return false;
}
/* The child process */
if (!run->pid) {
logMutexReset();
/*
* Reset sighandlers, and set alarm(1). It's a guarantee against dead-locks
* in the child, where we ensure here that the child process will either
* execve or get signaled by SIGALRM within 1 second.
*
* Those deadlocks typically stem from the fact, that malloc() can behave weirdly
* when fork()-ing a single thread of a process: e.g. with glibc < 2.24
* (or, Ubuntu's 2.23-0ubuntu6). For more see
* http://changelogs.ubuntu.com/changelogs/pool/main/g/glibc/glibc_2.23-0ubuntu7/changelog
*/
alarm(1);
signal(SIGALRM, SIG_DFL);
if (run->global->exe.persistent) {
if (dup2(sv[1], _HF_PERSISTENT_FD) == -1) {
PLOG_F("dup2('%d', '%d')", sv[1], _HF_PERSISTENT_FD);
}
close(sv[0]);
close(sv[1]);
}
if (!subproc_PrepareExecv(run)) {
LOG_E("subproc_PrepareExecv() failed");
exit(EXIT_FAILURE);
}
if (!arch_launchChild(run)) {
LOG_E("Error launching child process");
kill(run->global->threads.mainPid, SIGTERM);
_exit(1);
}
abort();
}
/* Parent */
LOG_D("Launched new process, pid=%d, thread: %" PRId32 " (concurrency: %zd)", (int)run->pid,
run->fuzzNo, run->global->threads.threadsMax);
arch_prepareParentAfterFork(run);
if (run->global->exe.persistent) {
close(sv[1]);
run->runState = _HF_RS_WAITING_FOR_INITIAL_READY;
LOG_I("Persistent mode: Launched new persistent pid=%d", (int)run->pid);
}
return true;
}
bool subproc_Run(run_t* run) {
run->timeStartedMillis = util_timeNowMillis();
if (!subproc_New(run)) {
LOG_E("subproc_New()");
return false;
}
arch_prepareParent(run);
arch_reapChild(run);
return true;
}
uint8_t subproc_System(run_t* run, const char* const argv[]) {
pid_t pid = arch_fork(run);
if (pid == -1) {
PLOG_E("Couldn't fork");
return 255;
}
if (!pid) {
logMutexReset();
setsid();
util_closeStdio(
/* close_stdin= */ true, /* close_stdout= */ false, /* close_stderr= */ false);
sigset_t sset;
sigemptyset(&sset);
if (sigprocmask(SIG_SETMASK, &sset, NULL) == -1) {
PLOG_W("sigprocmask(empty_set)");
}
execv(argv[0], (char* const*)&argv[0]);
PLOG_F("Couldn't execute '%s'", argv[0]);
return 255;
}
int flags = 0;
#if defined(__WNOTHREAD)
flags |= __WNOTHREAD;
#endif /* defined(__WNOTHREAD) */
#if defined(__WALL)
flags |= __WALL;
#endif /* defined(__WALL) */
for (;;) {
int status;
int ret = wait4(pid, &status, flags, NULL);
if (ret == -1 && errno == EINTR) {
continue;
}
if (ret == -1) {
PLOG_E("wait4() for process pid=%d", (int)pid);
return 255;
}
if (ret != pid) {
LOG_E("wait4() returned %d, but waited for %d", ret, (int)pid);
return 255;
}
if (WIFSIGNALED(status)) {
LOG_E("Command '%s' terminated with signal: %d", argv[0], WTERMSIG(status));
return (100 + WTERMSIG(status));
}
if (WIFEXITED(status)) {
if (WEXITSTATUS(status) == 0) {
return 0U;
}
LOG_E("Command '%s' returned with exit code %d", argv[0], WEXITSTATUS(status));
return 1U;
}
LOG_D("wait4() returned with status: %d", status);
}
}
void subproc_checkTimeLimit(run_t* run) {
if (!run->global->timing.tmOut) {
return;
}
int64_t curMillis = util_timeNowMillis();
int64_t diffMillis = curMillis - run->timeStartedMillis;
if (run->tmOutSignaled && (diffMillis > ((run->global->timing.tmOut + 1) * 1000))) {
/* Has this instance been already signaled due to timeout? Just, SIGKILL it */
LOG_W("pid=%d has already been signaled due to timeout. Killing it with SIGKILL", run->pid);
kill(run->pid, SIGKILL);
return;
}
if ((diffMillis > (run->global->timing.tmOut * 1000)) && !run->tmOutSignaled) {
run->tmOutSignaled = true;
LOG_W("pid=%d took too much time (limit %ld s). Killing it with %s", (int)run->pid,
(long)run->global->timing.tmOut,
run->global->timing.tmoutVTALRM ? "SIGVTALRM" : "SIGKILL");
if (run->global->timing.tmoutVTALRM) {
kill(run->pid, SIGVTALRM);
} else {
kill(run->pid, SIGKILL);
}
ATOMIC_POST_INC(run->global->cnts.timeoutedCnt);
}
}
void subproc_checkTermination(run_t* run) {
if (fuzz_isTerminating()) {
LOG_D("Killing pid=%d", (int)run->pid);
kill(run->pid, SIGKILL);
}
}
bool subproc_runThread(honggfuzz_t* hfuzz, pthread_t* thread, void* (*thread_func)(void*)) {
pthread_attr_t attr;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
pthread_attr_setstacksize(&attr, _HF_PTHREAD_STACKSIZE);
pthread_attr_setguardsize(&attr, (size_t)sysconf(_SC_PAGESIZE));
if (pthread_create(thread, &attr, thread_func, (void*)hfuzz) < 0) {
PLOG_W("Couldn't create a new thread");
return false;
}
pthread_attr_destroy(&attr);
return true;
}