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-rw-r--r--instrumentation/afl-compiler-rt.o.c1965
1 files changed, 1965 insertions, 0 deletions
diff --git a/instrumentation/afl-compiler-rt.o.c b/instrumentation/afl-compiler-rt.o.c
new file mode 100644
index 00000000..c635ae63
--- /dev/null
+++ b/instrumentation/afl-compiler-rt.o.c
@@ -0,0 +1,1965 @@
+/*
+   american fuzzy lop++ - instrumentation bootstrap
+   ------------------------------------------------
+
+   Copyright 2015, 2016 Google Inc. All rights reserved.
+   Copyright 2019-2020 AFLplusplus Project. 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
+
+
+*/
+
+#ifdef __ANDROID__
+  #include "android-ashmem.h"
+#endif
+#include "config.h"
+#include "types.h"
+#include "cmplog.h"
+#include "llvm-alternative-coverage.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <string.h>
+#include <assert.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <limits.h>
+#include <errno.h>
+
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#ifndef __HAIKU__
+  #include <sys/shm.h>
+#endif
+#include <sys/wait.h>
+#include <sys/types.h>
+
+#if !__GNUC__
+  #include "llvm/Config/llvm-config.h"
+#endif
+
+#ifdef __linux__
+  #include "snapshot-inl.h"
+#endif
+
+/* This is a somewhat ugly hack for the experimental 'trace-pc-guard' mode.
+   Basically, we need to make sure that the forkserver is initialized after
+   the LLVM-generated runtime initialization pass, not before. */
+
+#ifndef MAP_FIXED_NOREPLACE
+  #ifdef MAP_EXCL
+    #define MAP_FIXED_NOREPLACE MAP_EXCL | MAP_FIXED
+  #else
+    #define MAP_FIXED_NOREPLACE MAP_FIXED
+  #endif
+#endif
+
+#define CTOR_PRIO 3
+
+#include <sys/mman.h>
+#include <fcntl.h>
+
+/* Globals needed by the injected instrumentation. The __afl_area_initial region
+   is used for instrumentation output before __afl_map_shm() has a chance to
+   run. It will end up as .comm, so it shouldn't be too wasteful. */
+
+#if MAP_SIZE <= 65536
+  #define MAP_INITIAL_SIZE 2097152
+#else
+  #define MAP_INITIAL_SIZE MAP_SIZE
+#endif
+
+u8   __afl_area_initial[MAP_INITIAL_SIZE];
+u8 * __afl_area_ptr_dummy = __afl_area_initial;
+u8 * __afl_area_ptr = __afl_area_initial;
+u8 * __afl_area_ptr_backup = __afl_area_initial;
+u8 * __afl_dictionary;
+u8 * __afl_fuzz_ptr;
+u32  __afl_fuzz_len_dummy;
+u32 *__afl_fuzz_len = &__afl_fuzz_len_dummy;
+
+u32 __afl_final_loc;
+u32 __afl_map_size = MAP_SIZE;
+u32 __afl_dictionary_len;
+u64 __afl_map_addr;
+
+// for the __AFL_COVERAGE_ON/__AFL_COVERAGE_OFF features to work:
+int __afl_selective_coverage __attribute__((weak));
+int __afl_selective_coverage_start_off __attribute__((weak));
+int __afl_selective_coverage_temp = 1;
+
+#if defined(__ANDROID__) || defined(__HAIKU__)
+PREV_LOC_T __afl_prev_loc[NGRAM_SIZE_MAX];
+PREV_LOC_T __afl_prev_caller[CTX_MAX_K];
+u32        __afl_prev_ctx;
+u32        __afl_cmp_counter;
+#else
+__thread PREV_LOC_T __afl_prev_loc[NGRAM_SIZE_MAX];
+__thread PREV_LOC_T __afl_prev_caller[CTX_MAX_K];
+__thread u32        __afl_prev_ctx;
+__thread u32        __afl_cmp_counter;
+#endif
+
+int __afl_sharedmem_fuzzing __attribute__((weak));
+
+struct cmp_map *__afl_cmp_map;
+struct cmp_map *__afl_cmp_map_backup;
+
+/* Child pid? */
+
+static s32 child_pid;
+static void (*old_sigterm_handler)(int) = 0;
+
+/* Running in persistent mode? */
+
+static u8 is_persistent;
+
+/* Are we in sancov mode? */
+
+static u8 _is_sancov;
+
+/* Debug? */
+
+static u32 __afl_debug;
+
+/* Already initialized markers */
+
+u32 __afl_already_initialized_shm;
+u32 __afl_already_initialized_forkserver;
+u32 __afl_already_initialized_first;
+u32 __afl_already_initialized_second;
+
+/* Dummy pipe for area_is_valid() */
+
+static int __afl_dummy_fd[2] = {2, 2};
+
+/* ensure we kill the child on termination */
+
+void at_exit(int signal) {
+
+  if (child_pid > 0) { kill(child_pid, SIGKILL); }
+
+}
+
+/* Uninspired gcc plugin instrumentation */
+
+void __afl_trace(const u32 x) {
+
+  PREV_LOC_T prev = __afl_prev_loc[0];
+  __afl_prev_loc[0] = (x >> 1);
+
+  u8 *p = &__afl_area_ptr[prev ^ x];
+
+#if 1                                      /* enable for neverZero feature. */
+  #if __GNUC__
+  u8 c = __builtin_add_overflow(*p, 1, p);
+  *p += c;
+  #else
+  *p += 1 + ((u8)(1 + *p) == 0);
+  #endif
+#else
+  ++*p;
+#endif
+
+  return;
+
+}
+
+/* Error reporting to forkserver controller */
+
+void send_forkserver_error(int error) {
+
+  u32 status;
+  if (!error || error > 0xffff) return;
+  status = (FS_OPT_ERROR | FS_OPT_SET_ERROR(error));
+  if (write(FORKSRV_FD + 1, (char *)&status, 4) != 4) { return; }
+
+}
+
+/* SHM fuzzing setup. */
+
+static void __afl_map_shm_fuzz() {
+
+  char *id_str = getenv(SHM_FUZZ_ENV_VAR);
+
+  if (__afl_debug) {
+
+    fprintf(stderr, "DEBUG: fuzzcase shmem %s\n", id_str ? id_str : "none");
+
+  }
+
+  if (id_str) {
+
+    u8 *map = NULL;
+
+#ifdef USEMMAP
+    const char *shm_file_path = id_str;
+    int         shm_fd = -1;
+
+    /* create the shared memory segment as if it was a file */
+    shm_fd = shm_open(shm_file_path, O_RDWR, 0600);
+    if (shm_fd == -1) {
+
+      fprintf(stderr, "shm_open() failed for fuzz\n");
+      send_forkserver_error(FS_ERROR_SHM_OPEN);
+      exit(1);
+
+    }
+
+    map =
+        (u8 *)mmap(0, MAX_FILE + sizeof(u32), PROT_READ, MAP_SHARED, shm_fd, 0);
+
+#else
+    u32 shm_id = atoi(id_str);
+    map = (u8 *)shmat(shm_id, NULL, 0);
+
+#endif
+
+    /* Whooooops. */
+
+    if (!map || map == (void *)-1) {
+
+      perror("Could not access fuzzing shared memory");
+      send_forkserver_error(FS_ERROR_SHM_OPEN);
+      exit(1);
+
+    }
+
+    __afl_fuzz_len = (u32 *)map;
+    __afl_fuzz_ptr = map + sizeof(u32);
+
+    if (__afl_debug) {
+
+      fprintf(stderr, "DEBUG: successfully got fuzzing shared memory\n");
+
+    }
+
+  } else {
+
+    fprintf(stderr, "Error: variable for fuzzing shared memory is not set\n");
+    send_forkserver_error(FS_ERROR_SHM_OPEN);
+    exit(1);
+
+  }
+
+}
+
+/* SHM setup. */
+
+static void __afl_map_shm(void) {
+
+  if (__afl_already_initialized_shm) return;
+  __afl_already_initialized_shm = 1;
+
+  // if we are not running in afl ensure the map exists
+  if (!__afl_area_ptr) { __afl_area_ptr = __afl_area_ptr_dummy; }
+
+  char *id_str = getenv(SHM_ENV_VAR);
+
+  if (__afl_final_loc) {
+
+    if (__afl_final_loc % 64) {
+
+      __afl_final_loc = (((__afl_final_loc + 63) >> 6) << 6);
+
+    }
+
+    __afl_map_size = __afl_final_loc;
+
+    if (__afl_final_loc > MAP_SIZE) {
+
+      char *ptr;
+      u32   val = 0;
+      if ((ptr = getenv("AFL_MAP_SIZE")) != NULL) val = atoi(ptr);
+      if (val < __afl_final_loc) {
+
+        if (__afl_final_loc > FS_OPT_MAX_MAPSIZE) {
+
+          if (!getenv("AFL_QUIET"))
+            fprintf(stderr,
+                    "Error: AFL++ tools *require* to set AFL_MAP_SIZE to %u "
+                    "to be able to run this instrumented program!\n",
+                    __afl_final_loc);
+
+          if (id_str) {
+
+            send_forkserver_error(FS_ERROR_MAP_SIZE);
+            exit(-1);
+
+          }
+
+        } else {
+
+          if (!getenv("AFL_QUIET"))
+            fprintf(stderr,
+                    "Warning: AFL++ tools will need to set AFL_MAP_SIZE to %u "
+                    "to be able to run this instrumented program!\n",
+                    __afl_final_loc);
+
+        }
+
+      }
+
+    }
+
+  }
+
+  /* If we're running under AFL, attach to the appropriate region, replacing the
+     early-stage __afl_area_initial region that is needed to allow some really
+     hacky .init code to work correctly in projects such as OpenSSL. */
+
+  if (__afl_debug) {
+
+    fprintf(stderr,
+            "DEBUG: (1) id_str %s, __afl_area_ptr %p, __afl_area_initial %p, "
+            "__afl_area_ptr_dummy 0x%p, __afl_map_addr 0x%llx, MAP_SIZE %u, "
+            "__afl_final_loc %u, "
+            "max_size_forkserver %u/0x%x\n",
+            id_str == NULL ? "<null>" : id_str, __afl_area_ptr,
+            __afl_area_initial, __afl_area_ptr_dummy, __afl_map_addr, MAP_SIZE,
+            __afl_final_loc, FS_OPT_MAX_MAPSIZE, FS_OPT_MAX_MAPSIZE);
+
+  }
+
+  if (id_str) {
+
+    if (__afl_area_ptr && __afl_area_ptr != __afl_area_initial &&
+        __afl_area_ptr != __afl_area_ptr_dummy) {
+
+      if (__afl_map_addr) {
+
+        munmap((void *)__afl_map_addr, __afl_final_loc);
+
+      } else {
+
+        free(__afl_area_ptr);
+
+      }
+
+      __afl_area_ptr = __afl_area_ptr_dummy;
+
+    }
+
+#ifdef USEMMAP
+    const char *   shm_file_path = id_str;
+    int            shm_fd = -1;
+    unsigned char *shm_base = NULL;
+
+    /* create the shared memory segment as if it was a file */
+    shm_fd = shm_open(shm_file_path, O_RDWR, 0600);
+    if (shm_fd == -1) {
+
+      fprintf(stderr, "shm_open() failed\n");
+      send_forkserver_error(FS_ERROR_SHM_OPEN);
+      exit(1);
+
+    }
+
+    /* map the shared memory segment to the address space of the process */
+    if (__afl_map_addr) {
+
+      shm_base =
+          mmap((void *)__afl_map_addr, __afl_map_size, PROT_READ | PROT_WRITE,
+               MAP_FIXED_NOREPLACE | MAP_SHARED, shm_fd, 0);
+
+    } else {
+
+      shm_base = mmap(0, __afl_map_size, PROT_READ | PROT_WRITE, MAP_SHARED,
+                      shm_fd, 0);
+
+    }
+
+    close(shm_fd);
+    shm_fd = -1;
+
+    if (shm_base == MAP_FAILED) {
+
+      fprintf(stderr, "mmap() failed\n");
+      perror("mmap for map");
+
+      if (__afl_map_addr)
+        send_forkserver_error(FS_ERROR_MAP_ADDR);
+      else
+        send_forkserver_error(FS_ERROR_MMAP);
+
+      exit(2);
+
+    }
+
+    __afl_area_ptr = shm_base;
+#else
+    u32 shm_id = atoi(id_str);
+
+    if (__afl_map_size && __afl_map_size > MAP_SIZE) {
+
+      u8 *map_env = (u8 *)getenv("AFL_MAP_SIZE");
+      if (!map_env || atoi((char *)map_env) < MAP_SIZE) {
+
+        send_forkserver_error(FS_ERROR_MAP_SIZE);
+        _exit(1);
+
+      }
+
+    }
+
+    __afl_area_ptr = (u8 *)shmat(shm_id, (void *)__afl_map_addr, 0);
+
+    /* Whooooops. */
+
+    if (!__afl_area_ptr || __afl_area_ptr == (void *)-1) {
+
+      if (__afl_map_addr)
+        send_forkserver_error(FS_ERROR_MAP_ADDR);
+      else
+        send_forkserver_error(FS_ERROR_SHMAT);
+
+      perror("shmat for map");
+      _exit(1);
+
+    }
+
+#endif
+
+    /* Write something into the bitmap so that even with low AFL_INST_RATIO,
+       our parent doesn't give up on us. */
+
+    __afl_area_ptr[0] = 1;
+
+  } else if ((!__afl_area_ptr || __afl_area_ptr == __afl_area_initial) &&
+
+             __afl_map_addr) {
+
+    __afl_area_ptr = (u8 *)mmap(
+        (void *)__afl_map_addr, __afl_map_size, PROT_READ | PROT_WRITE,
+        MAP_FIXED_NOREPLACE | MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+
+    if (__afl_area_ptr == MAP_FAILED) {
+
+      fprintf(stderr, "can not acquire mmap for address %p\n",
+              (void *)__afl_map_addr);
+      send_forkserver_error(FS_ERROR_SHM_OPEN);
+      exit(1);
+
+    }
+
+  } else if (_is_sancov && __afl_area_ptr != __afl_area_initial) {
+
+    free(__afl_area_ptr);
+    __afl_area_ptr = NULL;
+
+    if (__afl_final_loc > MAP_INITIAL_SIZE) {
+
+      __afl_area_ptr = (u8 *)malloc(__afl_final_loc);
+
+    }
+
+    if (!__afl_area_ptr) { __afl_area_ptr = __afl_area_ptr_dummy; }
+
+  }
+
+  __afl_area_ptr_backup = __afl_area_ptr;
+
+  if (__afl_debug) {
+
+    fprintf(stderr,
+            "DEBUG: (2) id_str %s, __afl_area_ptr %p, __afl_area_initial %p, "
+            "__afl_area_ptr_dummy 0x%p, __afl_map_addr 0x%llx, MAP_SIZE "
+            "%u, __afl_final_loc %u, "
+            "max_size_forkserver %u/0x%x\n",
+            id_str == NULL ? "<null>" : id_str, __afl_area_ptr,
+            __afl_area_initial, __afl_area_ptr_dummy, __afl_map_addr, MAP_SIZE,
+            __afl_final_loc, FS_OPT_MAX_MAPSIZE, FS_OPT_MAX_MAPSIZE);
+
+  }
+
+  if (__afl_selective_coverage) {
+
+    if (__afl_map_size > MAP_INITIAL_SIZE) {
+
+      __afl_area_ptr_dummy = (u8 *)malloc(__afl_map_size);
+
+      if (__afl_area_ptr_dummy) {
+
+        if (__afl_selective_coverage_start_off) {
+
+          __afl_area_ptr = __afl_area_ptr_dummy;
+
+        }
+
+      } else {
+
+        fprintf(stderr, "Error: __afl_selective_coverage failed!\n");
+        __afl_selective_coverage = 0;
+        // continue;
+
+      }
+
+    }
+
+  }
+
+  id_str = getenv(CMPLOG_SHM_ENV_VAR);
+
+  if (__afl_debug) {
+
+    fprintf(stderr, "DEBUG: cmplog id_str %s\n",
+            id_str == NULL ? "<null>" : id_str);
+
+  }
+
+  if (id_str) {
+
+    if ((__afl_dummy_fd[1] = open("/dev/null", O_WRONLY)) < 0) {
+
+      if (pipe(__afl_dummy_fd) < 0) { __afl_dummy_fd[1] = 1; }
+
+    }
+
+#ifdef USEMMAP
+    const char *    shm_file_path = id_str;
+    int             shm_fd = -1;
+    struct cmp_map *shm_base = NULL;
+
+    /* create the shared memory segment as if it was a file */
+    shm_fd = shm_open(shm_file_path, O_RDWR, 0600);
+    if (shm_fd == -1) {
+
+      perror("shm_open() failed\n");
+      send_forkserver_error(FS_ERROR_SHM_OPEN);
+      exit(1);
+
+    }
+
+    /* map the shared memory segment to the address space of the process */
+    shm_base = mmap(0, sizeof(struct cmp_map), PROT_READ | PROT_WRITE,
+                    MAP_SHARED, shm_fd, 0);
+    if (shm_base == MAP_FAILED) {
+
+      close(shm_fd);
+      shm_fd = -1;
+
+      fprintf(stderr, "mmap() failed\n");
+      send_forkserver_error(FS_ERROR_SHM_OPEN);
+      exit(2);
+
+    }
+
+    __afl_cmp_map = shm_base;
+#else
+    u32 shm_id = atoi(id_str);
+
+    __afl_cmp_map = (struct cmp_map *)shmat(shm_id, NULL, 0);
+#endif
+
+    __afl_cmp_map_backup = __afl_cmp_map;
+
+    if (!__afl_cmp_map || __afl_cmp_map == (void *)-1) {
+
+      perror("shmat for cmplog");
+      send_forkserver_error(FS_ERROR_SHM_OPEN);
+      _exit(1);
+
+    }
+
+  }
+
+}
+
+/* unmap SHM. */
+
+static void __afl_unmap_shm(void) {
+
+  if (!__afl_already_initialized_shm) return;
+
+  char *id_str = getenv(SHM_ENV_VAR);
+
+  if (id_str) {
+
+#ifdef USEMMAP
+
+    munmap((void *)__afl_area_ptr, __afl_map_size);
+
+#else
+
+    shmdt((void *)__afl_area_ptr);
+
+#endif
+
+  } else if ((!__afl_area_ptr || __afl_area_ptr == __afl_area_initial) &&
+
+             __afl_map_addr) {
+
+    munmap((void *)__afl_map_addr, __afl_map_size);
+
+  }
+
+  __afl_area_ptr = __afl_area_ptr_dummy;
+
+  id_str = getenv(CMPLOG_SHM_ENV_VAR);
+
+  if (id_str) {
+
+#ifdef USEMMAP
+
+    munmap((void *)__afl_cmp_map, __afl_map_size);
+
+#else
+
+    shmdt((void *)__afl_cmp_map);
+
+#endif
+
+    __afl_cmp_map = NULL;
+
+  }
+
+  __afl_already_initialized_shm = 0;
+
+}
+
+#ifdef __linux__
+static void __afl_start_snapshots(void) {
+
+  static u8 tmp[4] = {0, 0, 0, 0};
+  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);
+
+  /* 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. */
+
+  status |= (FS_OPT_ENABLED | FS_OPT_SNAPSHOT);
+  if (__afl_sharedmem_fuzzing != 0) status |= FS_OPT_SHDMEM_FUZZ;
+  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;
+  memcpy(tmp, &status, 4);
+
+  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 (__afl_debug) {
+
+      fprintf(stderr, "target forkserver recv: %08x\n", was_killed);
+
+    }
+
+    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) &&
+        __afl_dictionary_len && __afl_dictionary) {
+
+      // 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;
+
+    if (already_read_first) {
+
+      already_read_first = 0;
+
+    } else {
+
+      /* Wait for parent by reading from the pipe. Abort if read fails. */
+      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) {
+
+        //(void)nice(-20);  // does not seem to improve
+
+        signal(SIGCHLD, old_sigchld_handler);
+        signal(SIGTERM, old_sigterm_handler);
+
+        close(FORKSRV_FD);
+        close(FORKSRV_FD + 1);
+
+        if (!afl_snapshot_take(AFL_SNAPSHOT_MMAP | AFL_SNAPSHOT_FDS |
+                               AFL_SNAPSHOT_REGS | AFL_SNAPSHOT_EXIT)) {
+
+          raise(SIGSTOP);
+
+        }
+
+        __afl_area_ptr[0] = 1;
+        memset(__afl_prev_loc, 0, NGRAM_SIZE_MAX * sizeof(PREV_LOC_T));
+
+        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, WUNTRACED) < 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);
+
+  }
+
+}
+
+#endif
+
+/* Fork server logic. */
+
+static void __afl_start_forkserver(void) {
+
+  if (__afl_already_initialized_forkserver) return;
+  __afl_already_initialized_forkserver = 1;
+
+  struct sigaction orig_action;
+  sigaction(SIGTERM, NULL, &orig_action);
+  old_sigterm_handler = orig_action.sa_handler;
+  signal(SIGTERM, at_exit);
+
+#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};
+  u32 status_for_fsrv = 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_for_fsrv |= (FS_OPT_SET_MAPSIZE(__afl_map_size) | FS_OPT_MAPSIZE);
+
+  }
+
+  if (__afl_dictionary_len && __afl_dictionary) {
+
+    status_for_fsrv |= FS_OPT_AUTODICT;
+
+  }
+
+  if (__afl_sharedmem_fuzzing != 0) { status_for_fsrv |= FS_OPT_SHDMEM_FUZZ; }
+  if (status_for_fsrv) { status_for_fsrv |= (FS_OPT_ENABLED); }
+  memcpy(tmp, &status_for_fsrv, 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 (__afl_debug) {
+
+      fprintf(stderr, "target forkserver recv: %08x\n", was_killed);
+
+    }
+
+    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) &&
+        __afl_dictionary_len && __afl_dictionary) {
+
+      // great lets pass the dictionary through the forkserver FD
+      u32 len = __afl_dictionary_len, offset = 0;
+
+      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) {
+
+        s32 ret;
+        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) {
+
+        //(void)nice(-20);
+
+        signal(SIGCHLD, old_sigchld_handler);
+        signal(SIGTERM, old_sigterm_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
+ * README.llvm.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;
+    __afl_selective_coverage_temp = 1;
+
+    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));
+      __afl_selective_coverage_temp = 1;
+
+      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_ptr_dummy;
+
+    }
+
+  }
+
+  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 (getenv("AFL_DISABLE_LLVM_INSTRUMENTATION")) {
+
+    init_done = 1;
+    is_persistent = 0;
+    __afl_sharedmem_fuzzing = 0;
+    if (__afl_area_ptr == NULL) __afl_area_ptr = __afl_area_ptr_dummy;
+
+    if (__afl_debug) {
+
+      fprintf(stderr,
+              "DEBUG: disabled instrumentation because of "
+              "AFL_DISABLE_LLVM_INSTRUMENTATION\n");
+
+    }
+
+  }
+
+  if (!init_done) {
+
+    __afl_start_forkserver();
+    init_done = 1;
+
+  }
+
+}
+
+/* Initialization of the forkserver - latest possible */
+
+__attribute__((constructor())) void __afl_auto_init(void) {
+
+  if (getenv("AFL_DISABLE_LLVM_INSTRUMENTATION")) return;
+
+  if (getenv(DEFER_ENV_VAR)) return;
+
+  __afl_manual_init();
+
+}
+
+/* Initialization of the shmem - earliest possible because of LTO fixed mem. */
+
+__attribute__((constructor(CTOR_PRIO))) void __afl_auto_early(void) {
+
+  is_persistent = !!getenv(PERSIST_ENV_VAR);
+
+  if (getenv("AFL_DISABLE_LLVM_INSTRUMENTATION")) return;
+
+  __afl_map_shm();
+
+}
+
+/* preset __afl_area_ptr #2 */
+
+__attribute__((constructor(1))) void __afl_auto_second(void) {
+
+  if (__afl_already_initialized_second) return;
+  __afl_already_initialized_second = 1;
+
+  if (getenv("AFL_DEBUG")) { __afl_debug = 1; }
+
+  if (getenv("AFL_DISABLE_LLVM_INSTRUMENTATION")) return;
+  u8 *ptr;
+
+  if (__afl_final_loc) {
+
+    if (__afl_area_ptr && __afl_area_ptr != __afl_area_initial)
+      free(__afl_area_ptr);
+
+    if (__afl_map_addr)
+      ptr = (u8 *)mmap((void *)__afl_map_addr, __afl_final_loc,
+                       PROT_READ | PROT_WRITE,
+                       MAP_FIXED_NOREPLACE | MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+    else
+      ptr = (u8 *)malloc(__afl_final_loc);
+
+    if (ptr && (ssize_t)ptr != -1) {
+
+      __afl_area_ptr = ptr;
+      __afl_area_ptr_backup = __afl_area_ptr;
+
+    }
+
+  }
+
+}  // ptr memleak report is a false positive
+
+/* preset __afl_area_ptr #1 - at constructor level 0 global variables have
+   not been set */
+
+__attribute__((constructor(0))) void __afl_auto_first(void) {
+
+  if (__afl_already_initialized_first) return;
+  __afl_already_initialized_first = 1;
+
+  if (getenv("AFL_DISABLE_LLVM_INSTRUMENTATION")) return;
+  u8 *ptr = (u8 *)malloc(MAP_INITIAL_SIZE);
+
+  if (ptr && (ssize_t)ptr != -1) {
+
+    __afl_area_ptr = ptr;
+    __afl_area_ptr_backup = __afl_area_ptr;
+
+  }
+
+}  // ptr memleak report is a false positive
+
+/* 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 README.llvm.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) {
+
+  // For stability analysis, if you want to know to which function unstable
+  // edge IDs belong - uncomment, recompile+install llvm_mode, recompile
+  // the target. libunwind and libbacktrace are better solutions.
+  // Set AFL_DEBUG_CHILD=1 and run afl-fuzz with 2>file to capture
+  // the backtrace output
+  /*
+  uint32_t unstable[] = { ... unstable edge IDs };
+  uint32_t idx;
+  char bt[1024];
+  for (idx = 0; i < sizeof(unstable)/sizeof(uint32_t); i++) {
+
+    if (unstable[idx] == __afl_area_ptr[*guard]) {
+
+      int bt_size = backtrace(bt, 256);
+      if (bt_size > 0) {
+
+        char **bt_syms = backtrace_symbols(bt, bt_size);
+        if (bt_syms) {
+
+          fprintf(stderr, "DEBUG: edge=%u caller=%s\n", unstable[idx],
+  bt_syms[0]);
+          free(bt_syms);
+
+        }
+
+      }
+
+    }
+
+  }
+
+  */
+
+#if (LLVM_VERSION_MAJOR < 9)
+
+  __afl_area_ptr[*guard]++;
+
+#else
+
+  __afl_area_ptr[*guard] =
+      __afl_area_ptr[*guard] + 1 + (__afl_area_ptr[*guard] == 255 ? 1 : 0);
+
+#endif
+
+}
+
+/* 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;
+
+  _is_sancov = 1;
+
+  if (__afl_debug) {
+
+    fprintf(stderr,
+            "Running __sanitizer_cov_trace_pc_guard_init: %p-%p (%lu edges) "
+            "after_fs=%u\n",
+            start, stop, (unsigned long)(stop - start),
+            __afl_already_initialized_forkserver);
+
+  }
+
+  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();
+
+  }
+
+  /* instrumented code is loaded *after* our forkserver is up. this is a
+     problem. We cannot prevent collisions then :( */
+  if (__afl_already_initialized_forkserver &&
+      __afl_final_loc + 1 + stop - start > __afl_map_size) {
+
+    if (__afl_debug) {
+
+      fprintf(stderr, "Warning: new instrumented code after the forkserver!\n");
+
+    }
+
+    __afl_final_loc = 2;
+
+    if (1 + stop - start > __afl_map_size) {
+
+      *(start++) = ++__afl_final_loc;
+
+      while (start < stop) {
+
+        if (R(100) < inst_ratio)
+          *start = ++__afl_final_loc % __afl_map_size;
+        else
+          *start = 0;
+
+        start++;
+
+      }
+
+      return;
+
+    }
+
+  }
+
+  /* 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++) = ++__afl_final_loc;
+
+  while (start < stop) {
+
+    if (R(100) < inst_ratio)
+      *start = ++__afl_final_loc;
+    else
+      *start = 0;
+
+    start++;
+
+  }
+
+  if (__afl_debug) {
+
+    fprintf(stderr,
+            "Done __sanitizer_cov_trace_pc_guard_init: __afl_final_loc = %u\n",
+            __afl_final_loc);
+
+  }
+
+  if (__afl_already_initialized_shm && __afl_final_loc > __afl_map_size) {
+
+    if (__afl_debug) {
+
+      fprintf(stderr, "Reinit shm necessary (+%u)\n",
+              __afl_final_loc - __afl_map_size);
+
+    }
+
+    __afl_unmap_shm();
+    __afl_map_shm();
+
+  }
+
+}
+
+///// CmpLog instrumentation
+
+void __cmplog_ins_hook1(uint8_t arg1, uint8_t arg2, uint8_t attr) {
+
+  // fprintf(stderr, "hook1 arg0=%02x arg1=%02x attr=%u\n",
+  //         (u8) arg1, (u8) arg2, attr);
+
+  if (unlikely(!__afl_cmp_map || arg1 == arg2)) return;
+
+  uintptr_t k = (uintptr_t)__builtin_return_address(0);
+  k = (k >> 4) ^ (k << 8);
+  k &= CMP_MAP_W - 1;
+
+  u32 hits;
+
+  if (__afl_cmp_map->headers[k].type != CMP_TYPE_INS) {
+
+    __afl_cmp_map->headers[k].type = CMP_TYPE_INS;
+    hits = 0;
+    __afl_cmp_map->headers[k].hits = 1;
+    __afl_cmp_map->headers[k].shape = 0;
+
+  } else {
+
+    hits = __afl_cmp_map->headers[k].hits++;
+
+  }
+
+  __afl_cmp_map->headers[k].attribute = attr;
+
+  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, uint8_t attr) {
+
+  if (unlikely(!__afl_cmp_map || arg1 == arg2)) return;
+
+  uintptr_t k = (uintptr_t)__builtin_return_address(0);
+  k = (k >> 4) ^ (k << 8);
+  k &= CMP_MAP_W - 1;
+
+  u32 hits;
+
+  if (__afl_cmp_map->headers[k].type != CMP_TYPE_INS) {
+
+    __afl_cmp_map->headers[k].type = CMP_TYPE_INS;
+    hits = 0;
+    __afl_cmp_map->headers[k].hits = 1;
+    __afl_cmp_map->headers[k].shape = 1;
+
+  } else {
+
+    hits = __afl_cmp_map->headers[k].hits++;
+
+    if (!__afl_cmp_map->headers[k].shape) {
+
+      __afl_cmp_map->headers[k].shape = 1;
+
+    }
+
+  }
+
+  __afl_cmp_map->headers[k].attribute = attr;
+
+  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, uint8_t attr) {
+
+  // fprintf(stderr, "hook4 arg0=%x arg1=%x attr=%u\n", arg1, arg2, attr);
+
+  if (unlikely(!__afl_cmp_map || arg1 == arg2)) return;
+
+  uintptr_t k = (uintptr_t)__builtin_return_address(0);
+  k = (k >> 4) ^ (k << 8);
+  k &= CMP_MAP_W - 1;
+
+  u32 hits;
+
+  if (__afl_cmp_map->headers[k].type != CMP_TYPE_INS) {
+
+    __afl_cmp_map->headers[k].type = CMP_TYPE_INS;
+    hits = 0;
+    __afl_cmp_map->headers[k].hits = 1;
+    __afl_cmp_map->headers[k].shape = 3;
+
+  } else {
+
+    hits = __afl_cmp_map->headers[k].hits++;
+
+    if (__afl_cmp_map->headers[k].shape < 3) {
+
+      __afl_cmp_map->headers[k].shape = 3;
+
+    }
+
+  }
+
+  __afl_cmp_map->headers[k].attribute = attr;
+
+  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, uint8_t attr) {
+
+  // fprintf(stderr, "hook8 arg0=%lx arg1=%lx attr=%u\n", arg1, arg2, attr);
+
+  if (unlikely(!__afl_cmp_map || arg1 == arg2)) return;
+
+  uintptr_t k = (uintptr_t)__builtin_return_address(0);
+  k = (k >> 4) ^ (k << 8);
+  k &= CMP_MAP_W - 1;
+
+  u32 hits;
+
+  if (__afl_cmp_map->headers[k].type != CMP_TYPE_INS) {
+
+    __afl_cmp_map->headers[k].type = CMP_TYPE_INS;
+    hits = 0;
+    __afl_cmp_map->headers[k].hits = 1;
+    __afl_cmp_map->headers[k].shape = 7;
+
+  } else {
+
+    hits = __afl_cmp_map->headers[k].hits++;
+
+    if (__afl_cmp_map->headers[k].shape < 7) {
+
+      __afl_cmp_map->headers[k].shape = 7;
+
+    }
+
+  }
+
+  __afl_cmp_map->headers[k].attribute = attr;
+
+  hits &= CMP_MAP_H - 1;
+  __afl_cmp_map->log[k][hits].v0 = arg1;
+  __afl_cmp_map->log[k][hits].v1 = arg2;
+
+}
+
+#ifdef WORD_SIZE_64
+// support for u24 to u120 via llvm _ExitInt(). size is in bytes minus 1
+void __cmplog_ins_hookN(uint128_t arg1, uint128_t arg2, uint8_t attr,
+                        uint8_t size) {
+
+  // fprintf(stderr, "hookN arg0=%llx:%llx arg1=%llx:%llx bytes=%u attr=%u\n",
+  // (u64)(arg1 >> 64), (u64)arg1, (u64)(arg2 >> 64), (u64)arg2, size + 1,
+  // attr);
+
+  if (unlikely(!__afl_cmp_map || arg1 == arg2)) return;
+
+  uintptr_t k = (uintptr_t)__builtin_return_address(0);
+  k = (k >> 4) ^ (k << 8);
+  k &= CMP_MAP_W - 1;
+
+  u32 hits;
+
+  if (__afl_cmp_map->headers[k].type != CMP_TYPE_INS) {
+
+    __afl_cmp_map->headers[k].type = CMP_TYPE_INS;
+    hits = 0;
+    __afl_cmp_map->headers[k].hits = 1;
+    __afl_cmp_map->headers[k].shape = size;
+
+  } else {
+
+    hits = __afl_cmp_map->headers[k].hits++;
+
+    if (__afl_cmp_map->headers[k].shape < size) {
+
+      __afl_cmp_map->headers[k].shape = size;
+
+    }
+
+  }
+
+  __afl_cmp_map->headers[k].attribute = attr;
+
+  hits &= CMP_MAP_H - 1;
+  __afl_cmp_map->log[k][hits].v0 = (u64)arg1;
+  __afl_cmp_map->log[k][hits].v1 = (u64)arg2;
+
+  if (size > 7) {
+
+    __afl_cmp_map->log[k][hits].v0_128 = (u64)(arg1 >> 64);
+    __afl_cmp_map->log[k][hits].v1_128 = (u64)(arg2 >> 64);
+
+  }
+
+}
+
+void __cmplog_ins_hook16(uint128_t arg1, uint128_t arg2, uint8_t attr) {
+
+  if (unlikely(!__afl_cmp_map)) return;
+
+  uintptr_t k = (uintptr_t)__builtin_return_address(0);
+  k = (k >> 4) ^ (k << 8);
+  k &= CMP_MAP_W - 1;
+
+  u32 hits;
+
+  if (__afl_cmp_map->headers[k].type != CMP_TYPE_INS) {
+
+    __afl_cmp_map->headers[k].type = CMP_TYPE_INS;
+    hits = 0;
+    __afl_cmp_map->headers[k].hits = 1;
+    __afl_cmp_map->headers[k].shape = 15;
+
+  } else {
+
+    hits = __afl_cmp_map->headers[k].hits++;
+
+    if (__afl_cmp_map->headers[k].shape < 15) {
+
+      __afl_cmp_map->headers[k].shape = 15;
+
+    }
+
+  }
+
+  __afl_cmp_map->headers[k].attribute = attr;
+
+  hits &= CMP_MAP_H - 1;
+  __afl_cmp_map->log[k][hits].v0 = (u64)arg1;
+  __afl_cmp_map->log[k][hits].v1 = (u64)arg2;
+  __afl_cmp_map->log[k][hits].v0_128 = (u64)(arg1 >> 64);
+  __afl_cmp_map->log[k][hits].v1_128 = (u64)(arg2 >> 64);
+
+}
+
+#endif
+
+void __sanitizer_cov_trace_cmp1(uint8_t arg1, uint8_t arg2) {
+
+  __cmplog_ins_hook1(arg1, arg2, 0);
+
+}
+
+void __sanitizer_cov_trace_const_cmp1(uint8_t arg1, uint8_t arg2) {
+
+  __cmplog_ins_hook1(arg1, arg2, 0);
+
+}
+
+void __sanitizer_cov_trace_cmp2(uint16_t arg1, uint16_t arg2) {
+
+  __cmplog_ins_hook2(arg1, arg2, 0);
+
+}
+
+void __sanitizer_cov_trace_const_cmp2(uint16_t arg1, uint16_t arg2) {
+
+  __cmplog_ins_hook2(arg1, arg2, 0);
+
+}
+
+void __sanitizer_cov_trace_cmp4(uint32_t arg1, uint32_t arg2) {
+
+  __cmplog_ins_hook4(arg1, arg2, 0);
+
+}
+
+void __sanitizer_cov_trace_cost_cmp4(uint32_t arg1, uint32_t arg2) {
+
+  __cmplog_ins_hook4(arg1, arg2, 0);
+
+}
+
+void __sanitizer_cov_trace_cmp8(uint64_t arg1, uint64_t arg2) {
+
+  __cmplog_ins_hook8(arg1, arg2, 0);
+
+}
+
+void __sanitizer_cov_trace_const_cmp8(uint64_t arg1, uint64_t arg2) {
+
+  __cmplog_ins_hook8(arg1, arg2, 0);
+
+}
+
+#ifdef WORD_SIZE_64
+void __sanitizer_cov_trace_cmp16(uint128_t arg1, uint128_t arg2) {
+
+  __cmplog_ins_hook16(arg1, arg2, 0);
+
+}
+
+#endif
+
+void __sanitizer_cov_trace_switch(uint64_t val, uint64_t *cases) {
+
+  if (unlikely(!__afl_cmp_map)) return;
+
+  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;
+
+    u32 hits;
+
+    if (__afl_cmp_map->headers[k].type != CMP_TYPE_INS) {
+
+      __afl_cmp_map->headers[k].type = CMP_TYPE_INS;
+      hits = 0;
+      __afl_cmp_map->headers[k].hits = 1;
+      __afl_cmp_map->headers[k].shape = 7;
+
+    } else {
+
+      hits = __afl_cmp_map->headers[k].hits++;
+
+      if (__afl_cmp_map->headers[k].shape < 7) {
+
+        __afl_cmp_map->headers[k].shape = 7;
+
+      }
+
+    }
+
+    __afl_cmp_map->headers[k].attribute = 1;
+
+    hits &= CMP_MAP_H - 1;
+    __afl_cmp_map->log[k][hits].v0 = val;
+    __afl_cmp_map->log[k][hits].v1 = cases[i + 2];
+
+  }
+
+}
+
+__attribute__((weak)) void *__asan_region_is_poisoned(void *beg, size_t size) {
+
+  return NULL;
+
+}
+
+// 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_valid(void *ptr, size_t len) {
+
+  if (unlikely(!ptr || __asan_region_is_poisoned(ptr, len))) { return 0; }
+
+  long r = syscall(SYS_write, __afl_dummy_fd[1], ptr, len);
+
+  if (r <= 0 || r > len) return 0;
+
+  // even if the write succeed this can be a false positive if we cross
+  // a page boundary. who knows why.
+
+  char *p = (char *)ptr;
+  long  page_size = sysconf(_SC_PAGE_SIZE);
+  char *page = (char *)((uintptr_t)p & ~(page_size - 1)) + page_size;
+
+  if (page > p + len) {
+
+    // no, not crossing a page boundary
+    return (int)r;
+
+  } else {
+
+    // yes it crosses a boundary, hence we can only return the length of
+    // rest of the first page, we cannot detect if the next page is valid
+    // or not, neither by SYS_write nor msync() :-(
+    return (int)(page - p);
+
+  }
+
+}
+
+void __cmplog_rtn_hook(u8 *ptr1, u8 *ptr2) {
+
+  /*
+    u32 i;
+    if (area_is_valid(ptr1, 32) <= 0 || area_is_valid(ptr2, 32) <= 0) return;
+    fprintf(stderr, "rtn arg0=");
+    for (i = 0; i < 32; i++)
+      fprintf(stderr, "%02x", ptr1[i]);
+    fprintf(stderr, " arg1=");
+    for (i = 0; i < 32; i++)
+      fprintf(stderr, "%02x", ptr2[i]);
+    fprintf(stderr, "\n");
+  */
+
+  if (unlikely(!__afl_cmp_map)) return;
+  // fprintf(stderr, "RTN1 %p %p\n", ptr1, ptr2);
+  int l1, l2;
+  if ((l1 = area_is_valid(ptr1, 32)) <= 0 ||
+      (l2 = area_is_valid(ptr2, 32)) <= 0)
+    return;
+  int len = MIN(l1, l2);
+
+  // fprintf(stderr, "RTN2 %u\n", len);
+  uintptr_t k = (uintptr_t)__builtin_return_address(0);
+  k = (k >> 4) ^ (k << 8);
+  k &= CMP_MAP_W - 1;
+
+  u32 hits;
+
+  if (__afl_cmp_map->headers[k].type != CMP_TYPE_RTN) {
+
+    __afl_cmp_map->headers[k].type = CMP_TYPE_RTN;
+    __afl_cmp_map->headers[k].hits = 1;
+    __afl_cmp_map->headers[k].shape = len - 1;
+    hits = 0;
+
+  } else {
+
+    hits = __afl_cmp_map->headers[k].hits++;
+
+    if (__afl_cmp_map->headers[k].shape < len) {
+
+      __afl_cmp_map->headers[k].shape = len - 1;
+
+    }
+
+  }
+
+  hits &= CMP_MAP_RTN_H - 1;
+  __builtin_memcpy(((struct cmpfn_operands *)__afl_cmp_map->log[k])[hits].v0,
+                   ptr1, len);
+  __builtin_memcpy(((struct cmpfn_operands *)__afl_cmp_map->log[k])[hits].v1,
+                   ptr2, len);
+  // fprintf(stderr, "RTN3\n");
+
+}
+
+// gcc libstdc++
+// _ZNKSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEE7compareEPKc
+static u8 *get_gcc_stdstring(u8 *string) {
+
+  u32 *len = (u32 *)(string + 8);
+
+  if (*len < 16) {  // in structure
+
+    return (string + 16);
+
+  } else {  // in memory
+
+    u8 **ptr = (u8 **)string;
+    return (*ptr);
+
+  }
+
+}
+
+// llvm libc++ _ZNKSt3__112basic_stringIcNS_11char_traitsIcEENS_9allocator
+//             IcEEE7compareEmmPKcm
+static u8 *get_llvm_stdstring(u8 *string) {
+
+  // length is in: if ((string[0] & 1) == 0) u8 len = (string[0] >> 1);
+  // or: if (string[0] & 1) u32 *len = (u32 *) (string + 8);
+
+  if (string[0] & 1) {  // in memory
+
+    u8 **ptr = (u8 **)(string + 16);
+    return (*ptr);
+
+  } else {  // in structure
+
+    return (string + 1);
+
+  }
+
+}
+
+void __cmplog_rtn_gcc_stdstring_cstring(u8 *stdstring, u8 *cstring) {
+
+  if (unlikely(!__afl_cmp_map)) return;
+  if (area_is_valid(stdstring, 32) <= 0 || area_is_valid(cstring, 32) <= 0)
+    return;
+
+  __cmplog_rtn_hook(get_gcc_stdstring(stdstring), cstring);
+
+}
+
+void __cmplog_rtn_gcc_stdstring_stdstring(u8 *stdstring1, u8 *stdstring2) {
+
+  if (unlikely(!__afl_cmp_map)) return;
+  if (area_is_valid(stdstring1, 32) <= 0 || area_is_valid(stdstring2, 32) <= 0)
+    return;
+
+  __cmplog_rtn_hook(get_gcc_stdstring(stdstring1),
+                    get_gcc_stdstring(stdstring2));
+
+}
+
+void __cmplog_rtn_llvm_stdstring_cstring(u8 *stdstring, u8 *cstring) {
+
+  if (unlikely(!__afl_cmp_map)) return;
+  if (area_is_valid(stdstring, 32) <= 0 || area_is_valid(cstring, 32) <= 0)
+    return;
+
+  __cmplog_rtn_hook(get_llvm_stdstring(stdstring), cstring);
+
+}
+
+void __cmplog_rtn_llvm_stdstring_stdstring(u8 *stdstring1, u8 *stdstring2) {
+
+  if (unlikely(!__afl_cmp_map)) return;
+  if (area_is_valid(stdstring1, 32) <= 0 || area_is_valid(stdstring2, 32) <= 0)
+    return;
+
+  __cmplog_rtn_hook(get_llvm_stdstring(stdstring1),
+                    get_llvm_stdstring(stdstring2));
+
+}
+
+/* COVERAGE manipulation features */
+
+// this variable is then used in the shm setup to create an additional map
+// if __afl_map_size > MAP_SIZE or cmplog is used.
+// Especially with cmplog this would result in a ~260MB mem increase per
+// target run.
+
+// disable coverage from this point onwards until turned on again
+void __afl_coverage_off() {
+
+  if (likely(__afl_selective_coverage)) {
+
+    __afl_area_ptr = __afl_area_ptr_dummy;
+    __afl_cmp_map = NULL;
+
+  }
+
+}
+
+// enable coverage
+void __afl_coverage_on() {
+
+  if (likely(__afl_selective_coverage && __afl_selective_coverage_temp)) {
+
+    __afl_area_ptr = __afl_area_ptr_backup;
+    __afl_cmp_map = __afl_cmp_map_backup;
+
+  }
+
+}
+
+// discard all coverage up to this point
+void __afl_coverage_discard() {
+
+  memset(__afl_area_ptr_backup, 0, __afl_map_size);
+  __afl_area_ptr_backup[0] = 1;
+
+  if (__afl_cmp_map) { memset(__afl_cmp_map, 0, sizeof(struct cmp_map)); }
+
+}
+
+// discard the testcase
+void __afl_coverage_skip() {
+
+  __afl_coverage_discard();
+
+  if (likely(is_persistent && __afl_selective_coverage)) {
+
+    __afl_coverage_off();
+    __afl_selective_coverage_temp = 0;
+
+  } else {
+
+    exit(0);
+
+  }
+
+}
+
+// mark this area as especially interesting
+void __afl_coverage_interesting(u8 val, u32 id) {
+
+  __afl_area_ptr[id] = val;
+
+}
+