mirror of
https://github.com/AFLplusplus/AFLplusplus.git
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1063 lines
25 KiB
C
1063 lines
25 KiB
C
/*
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american fuzzy lop++ - LLVM instrumentation bootstrap
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---------------------------------------------------
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Written by Laszlo Szekeres <lszekeres@google.com> and
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Michal Zalewski
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LLVM integration design comes from Laszlo Szekeres.
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Copyright 2015, 2016 Google Inc. All rights reserved.
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Copyright 2019-2020 AFLplusplus Project. All rights reserved.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at:
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http://www.apache.org/licenses/LICENSE-2.0
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This code is the rewrite of afl-as.h's main_payload.
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*/
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#ifdef __ANDROID__
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#include "android-ashmem.h"
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#endif
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#include "config.h"
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#include "types.h"
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#include "cmplog.h"
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#include "llvm-ngram-coverage.h"
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#include <stdio.h>
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#include <stdlib.h>
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#include <signal.h>
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#include <unistd.h>
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#include <string.h>
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#include <assert.h>
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#include <stdint.h>
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#include <errno.h>
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#include <sys/mman.h>
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#include <sys/shm.h>
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#include <sys/wait.h>
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#include <sys/types.h>
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#ifdef __linux__
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#include "snapshot-inl.h"
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#endif
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/* This is a somewhat ugly hack for the experimental 'trace-pc-guard' mode.
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Basically, we need to make sure that the forkserver is initialized after
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the LLVM-generated runtime initialization pass, not before. */
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#define CONST_PRIO 5
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#ifndef MAP_FIXED_NOREPLACE
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#define MAP_FIXED_NOREPLACE MAP_FIXED
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#endif
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#include <sys/mman.h>
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#include <fcntl.h>
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/* Globals needed by the injected instrumentation. The __afl_area_initial region
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is used for instrumentation output before __afl_map_shm() has a chance to
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run. It will end up as .comm, so it shouldn't be too wasteful. */
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#if MAP_SIZE <= 65536
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#define MAP_INITIAL_SIZE 256000
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#else
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#define MAP_INITIAL_SIZE MAP_SIZE
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#endif
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#ifdef AFL_REAL_LD
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u8 __afl_area_initial[MAP_INITIAL_SIZE];
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#else
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u8 __afl_area_initial[MAP_SIZE];
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#endif
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u8 * __afl_area_ptr = __afl_area_initial;
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u8 * __afl_dictionary;
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u8 * __afl_fuzz_ptr;
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u32 __afl_fuzz_len_dummy;
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u32 *__afl_fuzz_len = &__afl_fuzz_len_dummy;
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u32 __afl_final_loc;
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u32 __afl_map_size = MAP_SIZE;
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u32 __afl_dictionary_len;
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u64 __afl_map_addr;
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#ifdef __ANDROID__
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PREV_LOC_T __afl_prev_loc[NGRAM_SIZE_MAX];
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u32 __afl_prev_ctx;
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u32 __afl_cmp_counter;
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#else
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__thread PREV_LOC_T __afl_prev_loc[NGRAM_SIZE_MAX];
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__thread u32 __afl_prev_ctx;
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__thread u32 __afl_cmp_counter;
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#endif
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int __afl_sharedmem_fuzzing __attribute__((weak));
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struct cmp_map *__afl_cmp_map;
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/* Running in persistent mode? */
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static u8 is_persistent;
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/* Error reporting to forkserver controller */
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void send_forkserver_error(int error) {
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u32 status;
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if (!error || error > 0xffff) return;
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status = (FS_OPT_ERROR | FS_OPT_SET_ERROR(error));
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if (write(FORKSRV_FD + 1, (char *)&status, 4) != 4) return;
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}
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/* SHM fuzzing setup. */
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static void __afl_map_shm_fuzz() {
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char *id_str = getenv(SHM_FUZZ_ENV_VAR);
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if (id_str) {
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u8 *map = NULL;
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#ifdef USEMMAP
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const char * shm_file_path = id_str;
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int shm_fd = -1;
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unsigned char *shm_base = NULL;
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/* create the shared memory segment as if it was a file */
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shm_fd = shm_open(shm_file_path, O_RDWR, 0600);
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if (shm_fd == -1) {
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fprintf(stderr, "shm_open() failed for fuzz\n");
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send_forkserver_error(FS_ERROR_SHM_OPEN);
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exit(1);
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}
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map = (u8 *)mmap(0, MAX_FILE + sizeof(u32), PROT_READ, MAP_SHARED, shm_fd, 0);
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#else
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u32 shm_id = atoi(id_str);
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map = (u8 *)shmat(shm_id, NULL, 0);
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#endif
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/* Whooooops. */
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if (!map || map == (void *)-1) {
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perror("Could not access fuzzign shared memory");
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exit(1);
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}
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__afl_fuzz_len = (u32 *)map;
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__afl_fuzz_ptr = map + sizeof(u32);
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if (getenv("AFL_DEBUG")) {
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fprintf(stderr, "DEBUG: successfully got fuzzing shared memory\n");
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}
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} else {
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fprintf(stderr, "Error: variable for fuzzing shared memory is not set\n");
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exit(1);
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}
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}
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/* SHM setup. */
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static void __afl_map_shm(void) {
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char *id_str = getenv(SHM_ENV_VAR);
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if (__afl_final_loc) {
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__afl_map_size = __afl_final_loc;
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if (__afl_final_loc > MAP_SIZE) {
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char *ptr;
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u32 val = 0;
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if ((ptr = getenv("AFL_MAP_SIZE")) != NULL) val = atoi(ptr);
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if (val < __afl_final_loc) {
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if (__afl_final_loc > FS_OPT_MAX_MAPSIZE) {
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fprintf(stderr,
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"Error: AFL++ tools *require* to set AFL_MAP_SIZE to %u to "
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"be able to run this instrumented program!\n",
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__afl_final_loc);
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if (id_str) {
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send_forkserver_error(FS_ERROR_MAP_SIZE);
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exit(-1);
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}
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} else {
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fprintf(stderr,
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"Warning: AFL++ tools will need to set AFL_MAP_SIZE to %u to "
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"be able to run this instrumented program!\n",
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__afl_final_loc);
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}
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}
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}
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}
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/* If we're running under AFL, attach to the appropriate region, replacing the
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early-stage __afl_area_initial region that is needed to allow some really
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hacky .init code to work correctly in projects such as OpenSSL. */
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if (getenv("AFL_DEBUG"))
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fprintf(stderr,
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"DEBUG: id_str %s, __afl_map_addr 0x%llx, MAP_SIZE %u, "
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"__afl_final_loc %u, max_size_forkserver %u/0x%x\n",
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id_str == NULL ? "<null>" : id_str, __afl_map_addr, MAP_SIZE,
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__afl_final_loc, FS_OPT_MAX_MAPSIZE, FS_OPT_MAX_MAPSIZE);
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if (id_str) {
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#ifdef USEMMAP
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const char * shm_file_path = id_str;
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int shm_fd = -1;
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unsigned char *shm_base = NULL;
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/* create the shared memory segment as if it was a file */
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shm_fd = shm_open(shm_file_path, O_RDWR, 0600);
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if (shm_fd == -1) {
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fprintf(stderr, "shm_open() failed\n");
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send_forkserver_error(FS_ERROR_SHM_OPEN);
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exit(1);
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}
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/* map the shared memory segment to the address space of the process */
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if (__afl_map_addr) {
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shm_base =
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mmap((void *)__afl_map_addr, __afl_map_size, PROT_READ | PROT_WRITE,
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MAP_FIXED_NOREPLACE | MAP_SHARED, shm_fd, 0);
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} else {
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shm_base = mmap(0, __afl_map_size, PROT_READ | PROT_WRITE, MAP_SHARED,
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shm_fd, 0);
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}
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if (shm_base == MAP_FAILED) {
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close(shm_fd);
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shm_fd = -1;
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fprintf(stderr, "mmap() failed\n");
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if (__afl_map_addr)
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send_forkserver_error(FS_ERROR_MAP_ADDR);
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else
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send_forkserver_error(FS_ERROR_MMAP);
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exit(2);
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}
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__afl_area_ptr = shm_base;
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#else
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u32 shm_id = atoi(id_str);
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__afl_area_ptr = shmat(shm_id, (void *)__afl_map_addr, 0);
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#endif
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/* Whooooops. */
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if (__afl_area_ptr == (void *)-1) {
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if (__afl_map_addr)
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send_forkserver_error(FS_ERROR_MAP_ADDR);
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else
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send_forkserver_error(FS_ERROR_SHMAT);
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_exit(1);
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}
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/* Write something into the bitmap so that even with low AFL_INST_RATIO,
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our parent doesn't give up on us. */
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__afl_area_ptr[0] = 1;
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} else if (__afl_map_addr) {
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__afl_area_ptr =
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mmap((void *)__afl_map_addr, __afl_map_size, PROT_READ | PROT_WRITE,
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MAP_FIXED_NOREPLACE | MAP_SHARED | MAP_ANONYMOUS, -1, 0);
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if (__afl_area_ptr == MAP_FAILED) {
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fprintf(stderr, "can not aquire mmap for address %p\n",
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(void *)__afl_map_addr);
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exit(1);
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}
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}
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id_str = getenv(CMPLOG_SHM_ENV_VAR);
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if (getenv("AFL_DEBUG"))
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fprintf(stderr, "DEBUG: cmplog id_str %s\n",
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id_str == NULL ? "<null>" : id_str);
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if (id_str) {
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#ifdef USEMMAP
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const char * shm_file_path = id_str;
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int shm_fd = -1;
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unsigned char *shm_base = NULL;
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/* create the shared memory segment as if it was a file */
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shm_fd = shm_open(shm_file_path, O_RDWR, 0600);
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if (shm_fd == -1) {
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fprintf(stderr, "shm_open() failed\n");
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exit(1);
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}
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/* map the shared memory segment to the address space of the process */
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shm_base = mmap(0, sizeof(struct cmp_map), PROT_READ | PROT_WRITE,
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MAP_SHARED, shm_fd, 0);
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if (shm_base == MAP_FAILED) {
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close(shm_fd);
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shm_fd = -1;
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fprintf(stderr, "mmap() failed\n");
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exit(2);
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}
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__afl_cmp_map = shm_base;
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#else
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u32 shm_id = atoi(id_str);
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__afl_cmp_map = shmat(shm_id, NULL, 0);
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#endif
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if (__afl_cmp_map == (void *)-1) _exit(1);
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}
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}
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#ifdef __linux__
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static void __afl_start_snapshots(void) {
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static u8 tmp[4] = {0, 0, 0, 0};
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s32 child_pid;
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u32 status = 0;
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u32 already_read_first = 0;
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u32 was_killed;
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u8 child_stopped = 0;
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void (*old_sigchld_handler)(int) = 0; // = signal(SIGCHLD, SIG_DFL);
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/* Phone home and tell the parent that we're OK. If parent isn't there,
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assume we're not running in forkserver mode and just execute program. */
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status |= (FS_OPT_ENABLED | FS_OPT_SNAPSHOT);
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if (__afl_sharedmem_fuzzing != 0) status |= FS_OPT_SHDMEM_FUZZ;
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if (__afl_map_size <= FS_OPT_MAX_MAPSIZE)
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status |= (FS_OPT_SET_MAPSIZE(__afl_map_size) | FS_OPT_MAPSIZE);
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if (__afl_dictionary_len && __afl_dictionary) status |= FS_OPT_AUTODICT;
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memcpy(tmp, &status, 4);
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if (write(FORKSRV_FD + 1, tmp, 4) != 4) return;
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if (__afl_sharedmem_fuzzing || (__afl_dictionary_len && __afl_dictionary)) {
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if (read(FORKSRV_FD, &was_killed, 4) != 4) _exit(1);
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if ((was_killed & (0xffffffff & (FS_OPT_ENABLED | FS_OPT_SHDMEM_FUZZ))) ==
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(FS_OPT_ENABLED | FS_OPT_SHDMEM_FUZZ)) {
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__afl_map_shm_fuzz();
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}
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if ((was_killed & (FS_OPT_ENABLED | FS_OPT_AUTODICT)) ==
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(FS_OPT_ENABLED | FS_OPT_AUTODICT)) {
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// great lets pass the dictionary through the forkserver FD
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u32 len = __afl_dictionary_len, offset = 0;
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s32 ret;
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if (write(FORKSRV_FD + 1, &len, 4) != 4) {
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write(2, "Error: could not send dictionary len\n",
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strlen("Error: could not send dictionary len\n"));
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_exit(1);
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}
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while (len != 0) {
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ret = write(FORKSRV_FD + 1, __afl_dictionary + offset, len);
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if (ret < 1) {
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write(2, "Error: could not send dictionary\n",
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strlen("Error: could not send dictionary\n"));
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_exit(1);
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}
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len -= ret;
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offset += ret;
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}
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} else {
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// uh this forkserver does not understand extended option passing
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// or does not want the dictionary
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if (!__afl_fuzz_ptr) already_read_first = 1;
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}
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}
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while (1) {
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int status;
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if (already_read_first) {
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already_read_first = 0;
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} else {
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/* Wait for parent by reading from the pipe. Abort if read fails. */
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if (read(FORKSRV_FD, &was_killed, 4) != 4) _exit(1);
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}
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#ifdef _AFL_DOCUMENT_MUTATIONS
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if (__afl_fuzz_ptr) {
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static uint32_t counter = 0;
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char fn[32];
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sprintf(fn, "%09u:forkserver", counter);
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s32 fd_doc = open(fn, O_WRONLY | O_CREAT | O_TRUNC, 0600);
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if (fd_doc >= 0) {
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if (write(fd_doc, __afl_fuzz_ptr, *__afl_fuzz_len) != *__afl_fuzz_len) {
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fprintf(stderr, "write of mutation file failed: %s\n", fn);
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unlink(fn);
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}
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close(fd_doc);
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}
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counter++;
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}
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#endif
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/* If we stopped the child in persistent mode, but there was a race
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condition and afl-fuzz already issued SIGKILL, write off the old
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process. */
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if (child_stopped && was_killed) {
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child_stopped = 0;
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if (waitpid(child_pid, &status, 0) < 0) _exit(1);
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}
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if (!child_stopped) {
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/* Once woken up, create a clone of our process. */
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child_pid = fork();
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if (child_pid < 0) _exit(1);
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/* In child process: close fds, resume execution. */
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if (!child_pid) {
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signal(SIGCHLD, old_sigchld_handler);
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close(FORKSRV_FD);
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close(FORKSRV_FD + 1);
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if (!afl_snapshot_do()) { raise(SIGSTOP); }
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__afl_area_ptr[0] = 1;
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memset(__afl_prev_loc, 0, NGRAM_SIZE_MAX * sizeof(PREV_LOC_T));
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return;
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}
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} else {
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/* Special handling for persistent mode: if the child is alive but
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currently stopped, simply restart it with SIGCONT. */
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kill(child_pid, SIGCONT);
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child_stopped = 0;
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}
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/* In parent process: write PID to pipe, then wait for child. */
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if (write(FORKSRV_FD + 1, &child_pid, 4) != 4) _exit(1);
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if (waitpid(child_pid, &status, WUNTRACED) < 0) _exit(1);
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/* In persistent mode, the child stops itself with SIGSTOP to indicate
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a successful run. In this case, we want to wake it up without forking
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again. */
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if (WIFSTOPPED(status)) child_stopped = 1;
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/* Relay wait status to pipe, then loop back. */
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if (write(FORKSRV_FD + 1, &status, 4) != 4) _exit(1);
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}
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}
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#endif
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/* Fork server logic. */
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|
|
static void __afl_start_forkserver(void) {
|
|
|
|
#ifdef __linux__
|
|
if (/*!is_persistent &&*/ !__afl_cmp_map && !getenv("AFL_NO_SNAPSHOT") &&
|
|
afl_snapshot_init() >= 0) {
|
|
|
|
__afl_start_snapshots();
|
|
return;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
u8 tmp[4] = {0, 0, 0, 0};
|
|
s32 child_pid;
|
|
u32 status = 0;
|
|
u32 already_read_first = 0;
|
|
u32 was_killed;
|
|
|
|
u8 child_stopped = 0;
|
|
|
|
void (*old_sigchld_handler)(int) = 0; // = signal(SIGCHLD, SIG_DFL);
|
|
|
|
if (__afl_map_size <= FS_OPT_MAX_MAPSIZE)
|
|
status |= (FS_OPT_SET_MAPSIZE(__afl_map_size) | FS_OPT_MAPSIZE);
|
|
if (__afl_dictionary_len && __afl_dictionary) status |= FS_OPT_AUTODICT;
|
|
if (__afl_sharedmem_fuzzing != 0) status |= FS_OPT_SHDMEM_FUZZ;
|
|
if (status) status |= (FS_OPT_ENABLED);
|
|
memcpy(tmp, &status, 4);
|
|
|
|
/* Phone home and tell the parent that we're OK. If parent isn't there,
|
|
assume we're not running in forkserver mode and just execute program. */
|
|
|
|
if (write(FORKSRV_FD + 1, tmp, 4) != 4) return;
|
|
|
|
if (__afl_sharedmem_fuzzing || (__afl_dictionary_len && __afl_dictionary)) {
|
|
|
|
if (read(FORKSRV_FD, &was_killed, 4) != 4) _exit(1);
|
|
|
|
if ((was_killed & (FS_OPT_ENABLED | FS_OPT_SHDMEM_FUZZ)) ==
|
|
(FS_OPT_ENABLED | FS_OPT_SHDMEM_FUZZ)) {
|
|
|
|
__afl_map_shm_fuzz();
|
|
|
|
}
|
|
|
|
if ((was_killed & (FS_OPT_ENABLED | FS_OPT_AUTODICT)) ==
|
|
(FS_OPT_ENABLED | FS_OPT_AUTODICT)) {
|
|
|
|
// great lets pass the dictionary through the forkserver FD
|
|
u32 len = __afl_dictionary_len, offset = 0;
|
|
s32 ret;
|
|
|
|
if (write(FORKSRV_FD + 1, &len, 4) != 4) {
|
|
|
|
write(2, "Error: could not send dictionary len\n",
|
|
strlen("Error: could not send dictionary len\n"));
|
|
_exit(1);
|
|
|
|
}
|
|
|
|
while (len != 0) {
|
|
|
|
ret = write(FORKSRV_FD + 1, __afl_dictionary + offset, len);
|
|
|
|
if (ret < 1) {
|
|
|
|
write(2, "Error: could not send dictionary\n",
|
|
strlen("Error: could not send dictionary\n"));
|
|
_exit(1);
|
|
|
|
}
|
|
|
|
len -= ret;
|
|
offset += ret;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
// uh this forkserver does not understand extended option passing
|
|
// or does not want the dictionary
|
|
if (!__afl_fuzz_ptr) already_read_first = 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
while (1) {
|
|
|
|
int status;
|
|
|
|
/* Wait for parent by reading from the pipe. Abort if read fails. */
|
|
|
|
if (already_read_first) {
|
|
|
|
already_read_first = 0;
|
|
|
|
} else {
|
|
|
|
if (read(FORKSRV_FD, &was_killed, 4) != 4) _exit(1);
|
|
|
|
}
|
|
|
|
#ifdef _AFL_DOCUMENT_MUTATIONS
|
|
if (__afl_fuzz_ptr) {
|
|
|
|
static uint32_t counter = 0;
|
|
char fn[32];
|
|
sprintf(fn, "%09u:forkserver", counter);
|
|
s32 fd_doc = open(fn, O_WRONLY | O_CREAT | O_TRUNC, 0600);
|
|
if (fd_doc >= 0) {
|
|
|
|
if (write(fd_doc, __afl_fuzz_ptr, *__afl_fuzz_len) != *__afl_fuzz_len) {
|
|
|
|
fprintf(stderr, "write of mutation file failed: %s\n", fn);
|
|
unlink(fn);
|
|
|
|
}
|
|
|
|
close(fd_doc);
|
|
|
|
}
|
|
|
|
counter++;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
/* If we stopped the child in persistent mode, but there was a race
|
|
condition and afl-fuzz already issued SIGKILL, write off the old
|
|
process. */
|
|
|
|
if (child_stopped && was_killed) {
|
|
|
|
child_stopped = 0;
|
|
if (waitpid(child_pid, &status, 0) < 0) _exit(1);
|
|
|
|
}
|
|
|
|
if (!child_stopped) {
|
|
|
|
/* Once woken up, create a clone of our process. */
|
|
|
|
child_pid = fork();
|
|
if (child_pid < 0) _exit(1);
|
|
|
|
/* In child process: close fds, resume execution. */
|
|
|
|
if (!child_pid) {
|
|
|
|
signal(SIGCHLD, old_sigchld_handler);
|
|
|
|
close(FORKSRV_FD);
|
|
close(FORKSRV_FD + 1);
|
|
return;
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
/* Special handling for persistent mode: if the child is alive but
|
|
currently stopped, simply restart it with SIGCONT. */
|
|
|
|
kill(child_pid, SIGCONT);
|
|
child_stopped = 0;
|
|
|
|
}
|
|
|
|
/* In parent process: write PID to pipe, then wait for child. */
|
|
|
|
if (write(FORKSRV_FD + 1, &child_pid, 4) != 4) _exit(1);
|
|
|
|
if (waitpid(child_pid, &status, is_persistent ? WUNTRACED : 0) < 0)
|
|
_exit(1);
|
|
|
|
/* In persistent mode, the child stops itself with SIGSTOP to indicate
|
|
a successful run. In this case, we want to wake it up without forking
|
|
again. */
|
|
|
|
if (WIFSTOPPED(status)) child_stopped = 1;
|
|
|
|
/* Relay wait status to pipe, then loop back. */
|
|
|
|
if (write(FORKSRV_FD + 1, &status, 4) != 4) _exit(1);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
/* A simplified persistent mode handler, used as explained in
|
|
* llvm_mode/README.md. */
|
|
|
|
int __afl_persistent_loop(unsigned int max_cnt) {
|
|
|
|
static u8 first_pass = 1;
|
|
static u32 cycle_cnt;
|
|
|
|
if (first_pass) {
|
|
|
|
/* Make sure that every iteration of __AFL_LOOP() starts with a clean slate.
|
|
On subsequent calls, the parent will take care of that, but on the first
|
|
iteration, it's our job to erase any trace of whatever happened
|
|
before the loop. */
|
|
|
|
if (is_persistent) {
|
|
|
|
memset(__afl_area_ptr, 0, __afl_map_size);
|
|
__afl_area_ptr[0] = 1;
|
|
memset(__afl_prev_loc, 0, NGRAM_SIZE_MAX * sizeof(PREV_LOC_T));
|
|
|
|
}
|
|
|
|
cycle_cnt = max_cnt;
|
|
first_pass = 0;
|
|
return 1;
|
|
|
|
}
|
|
|
|
if (is_persistent) {
|
|
|
|
if (--cycle_cnt) {
|
|
|
|
raise(SIGSTOP);
|
|
|
|
__afl_area_ptr[0] = 1;
|
|
memset(__afl_prev_loc, 0, NGRAM_SIZE_MAX * sizeof(PREV_LOC_T));
|
|
|
|
return 1;
|
|
|
|
} else {
|
|
|
|
/* When exiting __AFL_LOOP(), make sure that the subsequent code that
|
|
follows the loop is not traced. We do that by pivoting back to the
|
|
dummy output region. */
|
|
|
|
__afl_area_ptr = __afl_area_initial;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
/* This one can be called from user code when deferred forkserver mode
|
|
is enabled. */
|
|
|
|
void __afl_manual_init(void) {
|
|
|
|
static u8 init_done;
|
|
|
|
if (!init_done) {
|
|
|
|
__afl_map_shm();
|
|
__afl_start_forkserver();
|
|
init_done = 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
/* Proper initialization routine. */
|
|
|
|
__attribute__((constructor(CONST_PRIO))) void __afl_auto_init(void) {
|
|
|
|
is_persistent = !!getenv(PERSIST_ENV_VAR);
|
|
|
|
if (getenv(DEFER_ENV_VAR)) return;
|
|
|
|
__afl_manual_init();
|
|
|
|
}
|
|
|
|
/* The following stuff deals with supporting -fsanitize-coverage=trace-pc-guard.
|
|
It remains non-operational in the traditional, plugin-backed LLVM mode.
|
|
For more info about 'trace-pc-guard', see llvm_mode/README.md.
|
|
|
|
The first function (__sanitizer_cov_trace_pc_guard) is called back on every
|
|
edge (as opposed to every basic block). */
|
|
|
|
void __sanitizer_cov_trace_pc_guard(uint32_t *guard) {
|
|
|
|
__afl_area_ptr[*guard]++;
|
|
|
|
}
|
|
|
|
/* Init callback. Populates instrumentation IDs. Note that we're using
|
|
ID of 0 as a special value to indicate non-instrumented bits. That may
|
|
still touch the bitmap, but in a fairly harmless way. */
|
|
|
|
void __sanitizer_cov_trace_pc_guard_init(uint32_t *start, uint32_t *stop) {
|
|
|
|
u32 inst_ratio = 100;
|
|
char *x;
|
|
|
|
if (start == stop || *start) return;
|
|
|
|
x = getenv("AFL_INST_RATIO");
|
|
if (x) inst_ratio = (u32)atoi(x);
|
|
|
|
if (!inst_ratio || inst_ratio > 100) {
|
|
|
|
fprintf(stderr, "[-] ERROR: Invalid AFL_INST_RATIO (must be 1-100).\n");
|
|
abort();
|
|
|
|
}
|
|
|
|
/* Make sure that the first element in the range is always set - we use that
|
|
to avoid duplicate calls (which can happen as an artifact of the underlying
|
|
implementation in LLVM). */
|
|
|
|
*(start++) = R(MAP_SIZE - 1) + 1;
|
|
|
|
while (start < stop) {
|
|
|
|
if (R(100) < inst_ratio)
|
|
*start = R(MAP_SIZE - 1) + 1;
|
|
else
|
|
*start = 0;
|
|
|
|
start++;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
///// CmpLog instrumentation
|
|
|
|
void __cmplog_ins_hook1(uint8_t arg1, uint8_t arg2) {
|
|
|
|
if (!__afl_cmp_map) return;
|
|
|
|
uintptr_t k = (uintptr_t)__builtin_return_address(0);
|
|
k = (k >> 4) ^ (k << 8);
|
|
k &= CMP_MAP_W - 1;
|
|
|
|
__afl_cmp_map->headers[k].type = CMP_TYPE_INS;
|
|
|
|
u32 hits = __afl_cmp_map->headers[k].hits;
|
|
__afl_cmp_map->headers[k].hits = hits + 1;
|
|
// if (!__afl_cmp_map->headers[k].cnt)
|
|
// __afl_cmp_map->headers[k].cnt = __afl_cmp_counter++;
|
|
|
|
__afl_cmp_map->headers[k].shape = 0;
|
|
|
|
hits &= CMP_MAP_H - 1;
|
|
__afl_cmp_map->log[k][hits].v0 = arg1;
|
|
__afl_cmp_map->log[k][hits].v1 = arg2;
|
|
|
|
}
|
|
|
|
void __cmplog_ins_hook2(uint16_t arg1, uint16_t arg2) {
|
|
|
|
if (!__afl_cmp_map) return;
|
|
|
|
uintptr_t k = (uintptr_t)__builtin_return_address(0);
|
|
k = (k >> 4) ^ (k << 8);
|
|
k &= CMP_MAP_W - 1;
|
|
|
|
__afl_cmp_map->headers[k].type = CMP_TYPE_INS;
|
|
|
|
u32 hits = __afl_cmp_map->headers[k].hits;
|
|
__afl_cmp_map->headers[k].hits = hits + 1;
|
|
|
|
__afl_cmp_map->headers[k].shape = 1;
|
|
|
|
hits &= CMP_MAP_H - 1;
|
|
__afl_cmp_map->log[k][hits].v0 = arg1;
|
|
__afl_cmp_map->log[k][hits].v1 = arg2;
|
|
|
|
}
|
|
|
|
void __cmplog_ins_hook4(uint32_t arg1, uint32_t arg2) {
|
|
|
|
if (!__afl_cmp_map) return;
|
|
|
|
uintptr_t k = (uintptr_t)__builtin_return_address(0);
|
|
k = (k >> 4) ^ (k << 8);
|
|
k &= CMP_MAP_W - 1;
|
|
|
|
__afl_cmp_map->headers[k].type = CMP_TYPE_INS;
|
|
|
|
u32 hits = __afl_cmp_map->headers[k].hits;
|
|
__afl_cmp_map->headers[k].hits = hits + 1;
|
|
|
|
__afl_cmp_map->headers[k].shape = 3;
|
|
|
|
hits &= CMP_MAP_H - 1;
|
|
__afl_cmp_map->log[k][hits].v0 = arg1;
|
|
__afl_cmp_map->log[k][hits].v1 = arg2;
|
|
|
|
}
|
|
|
|
void __cmplog_ins_hook8(uint64_t arg1, uint64_t arg2) {
|
|
|
|
if (!__afl_cmp_map) return;
|
|
|
|
uintptr_t k = (uintptr_t)__builtin_return_address(0);
|
|
k = (k >> 4) ^ (k << 8);
|
|
k &= CMP_MAP_W - 1;
|
|
|
|
__afl_cmp_map->headers[k].type = CMP_TYPE_INS;
|
|
|
|
u32 hits = __afl_cmp_map->headers[k].hits;
|
|
__afl_cmp_map->headers[k].hits = hits + 1;
|
|
|
|
__afl_cmp_map->headers[k].shape = 7;
|
|
|
|
hits &= CMP_MAP_H - 1;
|
|
__afl_cmp_map->log[k][hits].v0 = arg1;
|
|
__afl_cmp_map->log[k][hits].v1 = arg2;
|
|
|
|
}
|
|
|
|
#if defined(__APPLE__)
|
|
#pragma weak __sanitizer_cov_trace_const_cmp1 = __cmplog_ins_hook1
|
|
#pragma weak __sanitizer_cov_trace_const_cmp2 = __cmplog_ins_hook2
|
|
#pragma weak __sanitizer_cov_trace_const_cmp4 = __cmplog_ins_hook4
|
|
#pragma weak __sanitizer_cov_trace_const_cmp8 = __cmplog_ins_hook8
|
|
|
|
#pragma weak __sanitizer_cov_trace_cmp1 = __cmplog_ins_hook1
|
|
#pragma weak __sanitizer_cov_trace_cmp2 = __cmplog_ins_hook2
|
|
#pragma weak __sanitizer_cov_trace_cmp4 = __cmplog_ins_hook4
|
|
#pragma weak __sanitizer_cov_trace_cmp8 = __cmplog_ins_hook8
|
|
#else
|
|
void __sanitizer_cov_trace_const_cmp1(uint8_t arg1, uint8_t arg2)
|
|
__attribute__((alias("__cmplog_ins_hook1")));
|
|
void __sanitizer_cov_trace_const_cmp2(uint16_t arg1, uint16_t arg2)
|
|
__attribute__((alias("__cmplog_ins_hook2")));
|
|
void __sanitizer_cov_trace_const_cmp4(uint32_t arg1, uint32_t arg2)
|
|
__attribute__((alias("__cmplog_ins_hook4")));
|
|
void __sanitizer_cov_trace_const_cmp8(uint64_t arg1, uint64_t arg2)
|
|
__attribute__((alias("__cmplog_ins_hook8")));
|
|
|
|
void __sanitizer_cov_trace_cmp1(uint8_t arg1, uint8_t arg2)
|
|
__attribute__((alias("__cmplog_ins_hook1")));
|
|
void __sanitizer_cov_trace_cmp2(uint16_t arg1, uint16_t arg2)
|
|
__attribute__((alias("__cmplog_ins_hook2")));
|
|
void __sanitizer_cov_trace_cmp4(uint32_t arg1, uint32_t arg2)
|
|
__attribute__((alias("__cmplog_ins_hook4")));
|
|
void __sanitizer_cov_trace_cmp8(uint64_t arg1, uint64_t arg2)
|
|
__attribute__((alias("__cmplog_ins_hook8")));
|
|
#endif /* defined(__APPLE__) */
|
|
|
|
void __sanitizer_cov_trace_switch(uint64_t val, uint64_t *cases) {
|
|
|
|
for (uint64_t i = 0; i < cases[0]; i++) {
|
|
|
|
uintptr_t k = (uintptr_t)__builtin_return_address(0) + i;
|
|
k = (k >> 4) ^ (k << 8);
|
|
k &= CMP_MAP_W - 1;
|
|
|
|
__afl_cmp_map->headers[k].type = CMP_TYPE_INS;
|
|
|
|
u32 hits = __afl_cmp_map->headers[k].hits;
|
|
__afl_cmp_map->headers[k].hits = hits + 1;
|
|
|
|
__afl_cmp_map->headers[k].shape = 7;
|
|
|
|
hits &= CMP_MAP_H - 1;
|
|
__afl_cmp_map->log[k][hits].v0 = val;
|
|
__afl_cmp_map->log[k][hits].v1 = cases[i + 2];
|
|
|
|
}
|
|
|
|
}
|
|
|
|
// POSIX shenanigan to see if an area is mapped.
|
|
// If it is mapped as X-only, we have a problem, so maybe we should add a check
|
|
// to avoid to call it on .text addresses
|
|
static int area_is_mapped(void *ptr, size_t len) {
|
|
|
|
char *p = ptr;
|
|
char *page = (char *)((uintptr_t)p & ~(sysconf(_SC_PAGE_SIZE) - 1));
|
|
|
|
int r = msync(page, (p - page) + len, MS_ASYNC);
|
|
if (r < 0) return errno != ENOMEM;
|
|
return 1;
|
|
|
|
}
|
|
|
|
void __cmplog_rtn_hook(u8 *ptr1, u8 *ptr2) {
|
|
|
|
if (!__afl_cmp_map) return;
|
|
|
|
if (!area_is_mapped(ptr1, 32) || !area_is_mapped(ptr2, 32)) return;
|
|
|
|
uintptr_t k = (uintptr_t)__builtin_return_address(0);
|
|
k = (k >> 4) ^ (k << 8);
|
|
k &= CMP_MAP_W - 1;
|
|
|
|
__afl_cmp_map->headers[k].type = CMP_TYPE_RTN;
|
|
|
|
u32 hits = __afl_cmp_map->headers[k].hits;
|
|
__afl_cmp_map->headers[k].hits = hits + 1;
|
|
|
|
__afl_cmp_map->headers[k].shape = 31;
|
|
|
|
hits &= CMP_MAP_RTN_H - 1;
|
|
__builtin_memcpy(((struct cmpfn_operands *)__afl_cmp_map->log[k])[hits].v0,
|
|
ptr1, 32);
|
|
__builtin_memcpy(((struct cmpfn_operands *)__afl_cmp_map->log[k])[hits].v1,
|
|
ptr2, 32);
|
|
|
|
}
|
|
|