| /* |
| * |
| * honggfuzz - fuzzing routines |
| * ----------------------------------------- |
| * |
| * Authors: 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 "fuzz.h" |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <inttypes.h> |
| #include <libgen.h> |
| #include <pthread.h> |
| #include <signal.h> |
| #include <stddef.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/mman.h> |
| #include <sys/param.h> |
| #include <sys/stat.h> |
| #include <sys/time.h> |
| #include <sys/types.h> |
| #include <time.h> |
| #include <unistd.h> |
| |
| #include "arch.h" |
| #include "honggfuzz.h" |
| #include "input.h" |
| #include "libhfcommon/common.h" |
| #include "libhfcommon/files.h" |
| #include "libhfcommon/log.h" |
| #include "libhfcommon/util.h" |
| #include "mangle.h" |
| #include "report.h" |
| #include "sanitizers.h" |
| #include "socketfuzzer.h" |
| #include "subproc.h" |
| |
| static time_t termTimeStamp = 0; |
| |
| bool fuzz_isTerminating(void) { |
| if (ATOMIC_GET(termTimeStamp) != 0) { |
| return true; |
| } |
| return false; |
| } |
| |
| void fuzz_setTerminating(void) { |
| if (ATOMIC_GET(termTimeStamp) != 0) { |
| return; |
| } |
| ATOMIC_SET(termTimeStamp, time(NULL)); |
| } |
| |
| bool fuzz_shouldTerminate() { |
| if (ATOMIC_GET(termTimeStamp) == 0) { |
| return false; |
| } |
| if ((time(NULL) - ATOMIC_GET(termTimeStamp)) > 5) { |
| return true; |
| } |
| return false; |
| } |
| |
| static fuzzState_t fuzz_getState(honggfuzz_t* hfuzz) { |
| return ATOMIC_GET(hfuzz->feedback.state); |
| } |
| |
| static bool fuzz_writeCovFile(const char* dir, const uint8_t* data, size_t len) { |
| char fname[PATH_MAX]; |
| |
| uint64_t crc64f = util_CRC64(data, len); |
| uint64_t crc64r = util_CRC64Rev(data, len); |
| snprintf(fname, sizeof(fname), "%s/%016" PRIx64 "%016" PRIx64 ".%08" PRIx32 ".honggfuzz.cov", |
| dir, crc64f, crc64r, (uint32_t)len); |
| |
| if (files_exists(fname)) { |
| LOG_D("File '%s' already exists in the output corpus directory '%s'", fname, dir); |
| return true; |
| } |
| |
| LOG_D("Adding file '%s' to the corpus directory '%s'", fname, dir); |
| |
| if (!files_writeBufToFile(fname, data, len, O_WRONLY | O_CREAT | O_EXCL | O_CLOEXEC)) { |
| LOG_W("Couldn't write buffer to file '%s'", fname); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static void fuzz_addFileToFileQ(honggfuzz_t* hfuzz, const uint8_t* data, size_t len) { |
| ATOMIC_SET(hfuzz->timing.lastCovUpdate, time(NULL)); |
| |
| struct dynfile_t* dynfile = (struct dynfile_t*)util_Malloc(sizeof(struct dynfile_t)); |
| dynfile->size = len; |
| dynfile->data = (uint8_t*)util_Malloc(len); |
| memcpy(dynfile->data, data, len); |
| |
| MX_SCOPED_RWLOCK_WRITE(&hfuzz->io.dynfileq_mutex); |
| TAILQ_INSERT_TAIL(&hfuzz->io.dynfileq, dynfile, pointers); |
| hfuzz->io.dynfileqCnt++; |
| |
| if (hfuzz->socketFuzzer.enabled) { |
| /* Don't add coverage data to files in socketFuzzer mode */ |
| return; |
| } |
| |
| if (!fuzz_writeCovFile(hfuzz->io.covDirAll, data, len)) { |
| LOG_E("Couldn't save the coverage data to '%s'", hfuzz->io.covDirAll); |
| } |
| |
| /* No need to add files to the new coverage dir, if this is just the dry-run phase */ |
| if (fuzz_getState(hfuzz) == _HF_STATE_DYNAMIC_DRY_RUN || hfuzz->io.covDirNew == NULL) { |
| return; |
| } |
| |
| if (!fuzz_writeCovFile(hfuzz->io.covDirNew, data, len)) { |
| LOG_E("Couldn't save the new coverage data to '%s'", hfuzz->io.covDirNew); |
| } |
| } |
| |
| static void fuzz_setDynamicMainState(run_t* run) { |
| /* All threads need to indicate willingness to switch to the DYNAMIC_MAIN state. Count them! */ |
| static uint32_t cnt = 0; |
| ATOMIC_PRE_INC(cnt); |
| |
| static pthread_mutex_t state_mutex = PTHREAD_MUTEX_INITIALIZER; |
| MX_SCOPED_LOCK(&state_mutex); |
| |
| if (fuzz_getState(run->global) == _HF_STATE_DYNAMIC_MAIN) { |
| return; |
| } |
| |
| for (;;) { |
| /* Check if all threads have already reported in for changing state */ |
| if (ATOMIC_GET(cnt) == run->global->threads.threadsMax) { |
| break; |
| } |
| if (fuzz_isTerminating()) { |
| return; |
| } |
| usleep(1000 * 10); /* Check every 10ms */ |
| } |
| |
| LOG_I("Entering phase 2/2: Dynamic Main"); |
| snprintf(run->origFileName, sizeof(run->origFileName), "[DYNAMIC]"); |
| ATOMIC_SET(run->global->feedback.state, _HF_STATE_DYNAMIC_MAIN); |
| |
| /* |
| * If the initial fuzzing yielded no useful coverage, just add a single 1-byte file to the |
| * dynamic corpus, so the dynamic phase doesn't fail because of lack of useful inputs |
| */ |
| if (run->global->io.dynfileqCnt == 0) { |
| const char* single_byte = run->global->cfg.only_printable ? " " : "\0"; |
| fuzz_addFileToFileQ(run->global, (const uint8_t*)single_byte, 1U); |
| } |
| } |
| |
| static void fuzz_perfFeedback(run_t* run) { |
| if (run->global->feedback.skipFeedbackOnTimeout && run->tmOutSignaled) { |
| return; |
| } |
| |
| LOG_D("New file size: %zu, Perf feedback new/cur (instr,branch): %" PRIu64 "/%" PRIu64 |
| "/%" PRIu64 "/%" PRIu64 ", BBcnt new/total: %" PRIu64 "/%" PRIu64, |
| run->dynamicFileSz, run->linux.hwCnts.cpuInstrCnt, run->global->linux.hwCnts.cpuInstrCnt, |
| run->linux.hwCnts.cpuBranchCnt, run->global->linux.hwCnts.cpuBranchCnt, |
| run->linux.hwCnts.newBBCnt, run->global->linux.hwCnts.bbCnt); |
| |
| MX_SCOPED_LOCK(&run->global->feedback.feedback_mutex); |
| |
| uint64_t softCntPc = 0; |
| uint64_t softCntEdge = 0; |
| uint64_t softCntCmp = 0; |
| if (run->global->feedback.bbFd != -1) { |
| softCntPc = ATOMIC_GET(run->global->feedback.feedbackMap->pidFeedbackPc[run->fuzzNo]); |
| ATOMIC_CLEAR(run->global->feedback.feedbackMap->pidFeedbackPc[run->fuzzNo]); |
| softCntEdge = ATOMIC_GET(run->global->feedback.feedbackMap->pidFeedbackEdge[run->fuzzNo]); |
| ATOMIC_CLEAR(run->global->feedback.feedbackMap->pidFeedbackEdge[run->fuzzNo]); |
| softCntCmp = ATOMIC_GET(run->global->feedback.feedbackMap->pidFeedbackCmp[run->fuzzNo]); |
| ATOMIC_CLEAR(run->global->feedback.feedbackMap->pidFeedbackCmp[run->fuzzNo]); |
| } |
| |
| int64_t diff0 = run->global->linux.hwCnts.cpuInstrCnt - run->linux.hwCnts.cpuInstrCnt; |
| int64_t diff1 = run->global->linux.hwCnts.cpuBranchCnt - run->linux.hwCnts.cpuBranchCnt; |
| |
| /* Any increase in coverage (edge, pc, cmp, hw) counters forces adding input to the corpus */ |
| if (run->linux.hwCnts.newBBCnt > 0 || softCntPc > 0 || softCntEdge > 0 || softCntCmp > 0 || |
| diff0 < 0 || diff1 < 0) { |
| if (diff0 < 0) { |
| run->global->linux.hwCnts.cpuInstrCnt = run->linux.hwCnts.cpuInstrCnt; |
| } |
| if (diff1 < 0) { |
| run->global->linux.hwCnts.cpuBranchCnt = run->linux.hwCnts.cpuBranchCnt; |
| } |
| run->global->linux.hwCnts.bbCnt += run->linux.hwCnts.newBBCnt; |
| run->global->linux.hwCnts.softCntPc += softCntPc; |
| run->global->linux.hwCnts.softCntEdge += softCntEdge; |
| run->global->linux.hwCnts.softCntCmp += softCntCmp; |
| |
| LOG_I("Size:%zu (i,b,hw,edge,ip,cmp): %" PRIu64 "/%" PRIu64 "/%" PRIu64 "/%" PRIu64 |
| "/%" PRIu64 "/%" PRIu64 ", Tot:%" PRIu64 "/%" PRIu64 "/%" PRIu64 "/%" PRIu64 |
| "/%" PRIu64 "/%" PRIu64, |
| run->dynamicFileSz, run->linux.hwCnts.cpuInstrCnt, run->linux.hwCnts.cpuBranchCnt, |
| run->linux.hwCnts.newBBCnt, softCntEdge, softCntPc, softCntCmp, |
| run->global->linux.hwCnts.cpuInstrCnt, run->global->linux.hwCnts.cpuBranchCnt, |
| run->global->linux.hwCnts.bbCnt, run->global->linux.hwCnts.softCntEdge, |
| run->global->linux.hwCnts.softCntPc, run->global->linux.hwCnts.softCntCmp); |
| |
| fuzz_addFileToFileQ(run->global, run->dynamicFile, run->dynamicFileSz); |
| |
| if (run->global->socketFuzzer.enabled) { |
| LOG_D("SocketFuzzer: fuzz: new BB (perf)"); |
| fuzz_notifySocketFuzzerNewCov(run->global); |
| } |
| } |
| } |
| |
| /* Return value indicates whether report file should be updated with the current verified crash */ |
| static bool fuzz_runVerifier(run_t* run) { |
| if (!run->crashFileName[0] || !run->backtrace) { |
| return false; |
| } |
| |
| uint64_t backtrace = run->backtrace; |
| |
| char origCrashPath[PATH_MAX]; |
| snprintf(origCrashPath, sizeof(origCrashPath), "%s", run->crashFileName); |
| /* Workspace is inherited, just append a extra suffix */ |
| char verFile[PATH_MAX]; |
| snprintf(verFile, sizeof(verFile), "%s.verified", origCrashPath); |
| |
| if (files_exists(verFile)) { |
| LOG_D("Crash file to verify '%s' is already verified as '%s'", origCrashPath, verFile); |
| return false; |
| } |
| |
| for (int i = 0; i < _HF_VERIFIER_ITER; i++) { |
| LOG_I("Launching verifier for HASH: %" PRIx64 " (iteration: %d out of %d)", run->backtrace, |
| i + 1, _HF_VERIFIER_ITER); |
| run->timeStartedMillis = 0; |
| run->backtrace = 0; |
| run->access = 0; |
| run->exception = 0; |
| run->mainWorker = false; |
| |
| if (!subproc_Run(run)) { |
| LOG_F("subproc_Run()"); |
| } |
| |
| /* If stack hash doesn't match skip name tag and exit */ |
| if (run->backtrace != backtrace) { |
| LOG_E("Verifier stack mismatch: (original) %" PRIx64 " != (new) %" PRIx64, backtrace, |
| run->backtrace); |
| run->backtrace = backtrace; |
| return true; |
| } |
| |
| LOG_I("Verifier for HASH: %" PRIx64 " (iteration: %d, left: %d). MATCH!", run->backtrace, |
| i + 1, _HF_VERIFIER_ITER - i - 1); |
| } |
| |
| /* Copy file with new suffix & remove original copy */ |
| int fd = TEMP_FAILURE_RETRY(open(verFile, O_CREAT | O_EXCL | O_WRONLY, 0600)); |
| if (fd == -1 && errno == EEXIST) { |
| LOG_I("It seems that '%s' already exists, skipping", verFile); |
| return false; |
| } |
| if (fd == -1) { |
| PLOG_E("Couldn't create '%s'", verFile); |
| return true; |
| } |
| defer { |
| close(fd); |
| }; |
| if (!files_writeToFd(fd, run->dynamicFile, run->dynamicFileSz)) { |
| LOG_E("Couldn't save verified file as '%s'", verFile); |
| unlink(verFile); |
| return true; |
| } |
| |
| LOG_I("Verified crash for HASH: %" PRIx64 " and saved it as '%s'", backtrace, verFile); |
| ATOMIC_POST_INC(run->global->cnts.verifiedCrashesCnt); |
| |
| return true; |
| } |
| |
| static bool fuzz_fetchInput(run_t* run) { |
| if (fuzz_getState(run->global) == _HF_STATE_DYNAMIC_DRY_RUN) { |
| run->mutationsPerRun = 0U; |
| if (input_prepareStaticFile(run, /* rewind= */ false)) { |
| return true; |
| } |
| fuzz_setDynamicMainState(run); |
| run->mutationsPerRun = run->global->mutate.mutationsPerRun; |
| } |
| |
| if (fuzz_getState(run->global) == _HF_STATE_DYNAMIC_MAIN) { |
| if (run->global->exe.externalCommand) { |
| if (!input_prepareExternalFile(run)) { |
| LOG_E("input_prepareFileExternally() failed"); |
| return false; |
| } |
| } else if (!input_prepareDynamicInput(run)) { |
| LOG_E("input_prepareFileDynamically() failed"); |
| return false; |
| } |
| } |
| |
| if (fuzz_getState(run->global) == _HF_STATE_STATIC) { |
| if (run->global->exe.externalCommand) { |
| if (!input_prepareExternalFile(run)) { |
| LOG_E("input_prepareFileExternally() failed"); |
| return false; |
| } |
| } else if (!input_prepareStaticFile(run, true /* rewind */)) { |
| LOG_E("input_prepareFile() failed"); |
| return false; |
| } |
| } |
| |
| if (run->global->exe.postExternalCommand && !input_postProcessFile(run)) { |
| LOG_E("input_postProcessFile() failed"); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static void fuzz_fuzzLoop(run_t* run) { |
| run->timeStartedMillis = 0; |
| run->crashFileName[0] = '\0'; |
| run->pc = 0; |
| run->backtrace = 0; |
| run->access = 0; |
| run->exception = 0; |
| run->report[0] = '\0'; |
| run->mainWorker = true; |
| run->mutationsPerRun = run->global->mutate.mutationsPerRun; |
| run->dynamicFileSz = 0; |
| run->dynamicFileCopyFd = -1; |
| run->tmOutSignaled = false; |
| |
| run->linux.hwCnts.cpuInstrCnt = 0; |
| run->linux.hwCnts.cpuBranchCnt = 0; |
| run->linux.hwCnts.bbCnt = 0; |
| run->linux.hwCnts.newBBCnt = 0; |
| |
| if (!fuzz_fetchInput(run)) { |
| LOG_F("Cound't prepare input for fuzzing"); |
| } |
| if (!subproc_Run(run)) { |
| LOG_F("Couldn't run fuzzed command"); |
| } |
| |
| if (run->global->feedback.dynFileMethod != _HF_DYNFILE_NONE) { |
| fuzz_perfFeedback(run); |
| } |
| if (run->global->cfg.useVerifier && !fuzz_runVerifier(run)) { |
| return; |
| } |
| report_Report(run); |
| } |
| |
| static void fuzz_fuzzLoopSocket(run_t* run) { |
| run->pid = 0; |
| run->timeStartedMillis = 0; |
| run->crashFileName[0] = '\0'; |
| run->pc = 0; |
| run->backtrace = 0; |
| run->access = 0; |
| run->exception = 0; |
| run->report[0] = '\0'; |
| run->mainWorker = true; |
| run->mutationsPerRun = run->global->mutate.mutationsPerRun; |
| run->dynamicFileSz = 0; |
| run->dynamicFileCopyFd = -1; |
| run->tmOutSignaled = false; |
| |
| run->linux.hwCnts.cpuInstrCnt = 0; |
| run->linux.hwCnts.cpuBranchCnt = 0; |
| run->linux.hwCnts.bbCnt = 0; |
| run->linux.hwCnts.newBBCnt = 0; |
| |
| LOG_I("------------------------------------------------------"); |
| |
| /* First iteration: Start target |
| Other iterations: re-start target, if necessary |
| subproc_Run() will decide by itself if a restart is necessary, via |
| subproc_New() |
| */ |
| LOG_D("------[ 1: subproc_run"); |
| if (!subproc_Run(run)) { |
| LOG_W("Couldn't run server"); |
| } |
| |
| /* Tell the external fuzzer to send data to target |
| The fuzzer will notify us when finished; block until then. |
| */ |
| LOG_D("------[ 2: fetch input"); |
| if (!fuzz_waitForExternalInput(run)) { |
| /* Fuzzer could not connect to target, and told us to |
| restart it. Do it on the next iteration. */ |
| LOG_D("------[ 2.1: Target down, will restart it"); |
| return; |
| } |
| |
| LOG_D("------[ 3: feedback"); |
| if (run->global->feedback.dynFileMethod != _HF_DYNFILE_NONE) { |
| fuzz_perfFeedback(run); |
| } |
| if (run->global->cfg.useVerifier && !fuzz_runVerifier(run)) { |
| return; |
| } |
| |
| report_Report(run); |
| } |
| |
| static void* fuzz_threadNew(void* arg) { |
| honggfuzz_t* hfuzz = (honggfuzz_t*)arg; |
| unsigned int fuzzNo = ATOMIC_POST_INC(hfuzz->threads.threadsActiveCnt); |
| LOG_I("Launched new fuzzing thread, no. #%" PRId32, fuzzNo); |
| |
| run_t run = { |
| .global = hfuzz, |
| .pid = 0, |
| .dynfileqCurrent = NULL, |
| .dynamicFile = NULL, |
| .dynamicFileFd = -1, |
| .fuzzNo = fuzzNo, |
| .persistentSock = -1, |
| .tmOutSignaled = false, |
| .origFileName = "[DYNAMIC]", |
| }; |
| |
| /* Do not try to handle input files with socketfuzzer */ |
| if (!hfuzz->socketFuzzer.enabled) { |
| if (!(run.dynamicFile = files_mapSharedMem(hfuzz->mutate.maxFileSz, &run.dynamicFileFd, |
| "hfuzz-input", run.global->io.workDir))) { |
| LOG_F("Couldn't create an input file of size: %zu", hfuzz->mutate.maxFileSz); |
| } |
| } |
| defer { |
| if (run.dynamicFileFd != -1) { |
| close(run.dynamicFileFd); |
| } |
| }; |
| |
| if (!arch_archThreadInit(&run)) { |
| LOG_F("Could not initialize the thread"); |
| } |
| |
| for (;;) { |
| /* Check if dry run mode with verifier enabled */ |
| if (run.global->mutate.mutationsPerRun == 0U && run.global->cfg.useVerifier && |
| !hfuzz->socketFuzzer.enabled) { |
| if (ATOMIC_POST_INC(run.global->cnts.mutationsCnt) >= run.global->io.fileCnt) { |
| ATOMIC_POST_INC(run.global->threads.threadsFinished); |
| break; |
| } |
| } |
| /* Check for max iterations limit if set */ |
| else if ((ATOMIC_POST_INC(run.global->cnts.mutationsCnt) >= |
| run.global->mutate.mutationsMax) && |
| run.global->mutate.mutationsMax) { |
| ATOMIC_POST_INC(run.global->threads.threadsFinished); |
| break; |
| } |
| |
| input_setSize(&run, run.global->mutate.maxFileSz); |
| if (hfuzz->socketFuzzer.enabled) { |
| fuzz_fuzzLoopSocket(&run); |
| } else { |
| fuzz_fuzzLoop(&run); |
| } |
| |
| if (fuzz_isTerminating()) { |
| break; |
| } |
| |
| if (run.global->cfg.exitUponCrash && ATOMIC_GET(run.global->cnts.crashesCnt) > 0) { |
| LOG_I("Seen a crash. Terminating all fuzzing threads"); |
| fuzz_setTerminating(); |
| break; |
| } |
| } |
| |
| if (run.pid) { |
| kill(run.pid, SIGKILL); |
| } |
| |
| LOG_I("Terminating thread no. #%" PRId32 ", left: %zu", fuzzNo, |
| hfuzz->threads.threadsMax - run.global->threads.threadsFinished); |
| ATOMIC_POST_INC(run.global->threads.threadsFinished); |
| pthread_kill(run.global->threads.mainThread, SIGALRM); |
| return NULL; |
| } |
| |
| static void fuzz_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_JOINABLE); |
| 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_F("Couldn't create a new thread"); |
| } |
| |
| pthread_attr_destroy(&attr); |
| |
| return; |
| } |
| |
| void fuzz_threadsStart(honggfuzz_t* hfuzz, pthread_t* threads) { |
| if (!arch_archInit(hfuzz)) { |
| LOG_F("Couldn't prepare arch for fuzzing"); |
| } |
| if (!sanitizers_Init(hfuzz)) { |
| LOG_F("Couldn't prepare sanitizer options"); |
| } |
| |
| if (hfuzz->socketFuzzer.enabled) { |
| /* Don't do dry run with socketFuzzer */ |
| LOG_I("Entering phase - Feedback Driven Mode (SocketFuzzer)"); |
| hfuzz->feedback.state = _HF_STATE_DYNAMIC_MAIN; |
| } else if (hfuzz->feedback.dynFileMethod != _HF_DYNFILE_NONE) { |
| LOG_I("Entering phase 1/2: Dry Run"); |
| hfuzz->feedback.state = _HF_STATE_DYNAMIC_DRY_RUN; |
| } else { |
| LOG_I("Entering phase: Static"); |
| hfuzz->feedback.state = _HF_STATE_STATIC; |
| } |
| |
| for (size_t i = 0; i < hfuzz->threads.threadsMax; i++) { |
| fuzz_runThread(hfuzz, &threads[i], fuzz_threadNew); |
| } |
| } |
| |
| void fuzz_threadsStop(honggfuzz_t* hfuzz, pthread_t* threads) { |
| for (size_t i = 0; i < hfuzz->threads.threadsMax; i++) { |
| void* retval; |
| if (pthread_join(threads[i], &retval) != 0) { |
| PLOG_F("Couldn't pthread_join() thread: %zu", i); |
| } |
| } |
| LOG_I("All threads done"); |
| } |
