AFL_NO_SYNC

docs/Changelog.md

@@ -10,6 +10,7 @@
       three times faster. The reason for this is unknown.
     - added AFL_DISABLE_REDUNDANT for huge queues
     - fix AFL_PERSISTENT_RECORD
+    - added `AFL_NO_SYNC` environment variable that does what you think it does
     - run custom_post_process after standard trimming
     - prevent filenames in the queue that have spaces
     - minor fix for FAST schedules
@@ -32,6 +33,7 @@
   * afl-showmap
     - fix memory leak on shmem testcase usage (thanks to @ndrewh)
     - minor fix to collect coverage -C (thanks to @bet4it)
+  * libtokencap: script generate_libtoken_dict.sh added by @a-shvedov 
   * enhanced the ASAN configuration
 
 

docs/env_variables.md

@@ -588,6 +588,9 @@ checks or alter some of the more exotic semantics of the tool:
     between fuzzing instances synchronization. Default sync time is 30 minutes,
     note that time is halved for -M main nodes.
 
+  - `AFL_NO_SYNC` disables any syncing whatsoever and takes priority on all
+    other syncing parameters.
+
   - Setting `AFL_TARGET_ENV` causes AFL++ to set extra environment variables for
     the target binary. Example: `AFL_TARGET_ENV="VAR1=1 VAR2='a b c'" afl-fuzz
     ... `. This exists mostly for things like `LD_LIBRARY_PATH` but it would

include/afl-fuzz.h

@@ -457,7 +457,7 @@ typedef struct afl_env_vars {
       afl_no_startup_calibration, afl_no_warn_instability,
       afl_post_process_keep_original, afl_crashing_seeds_as_new_crash,
       afl_final_sync, afl_ignore_seed_problems, afl_disable_redundant,
-      afl_sha1_filenames;
+      afl_sha1_filenames, afl_no_sync;
 
   u8 *afl_tmpdir, *afl_custom_mutator_library, *afl_python_module, *afl_path,
       *afl_hang_tmout, *afl_forksrv_init_tmout, *afl_preload,

include/envs.h

@@ -81,14 +81,13 @@ static char *afl_environment_variables[] = {
     "AFL_LLVM_MAP_DYNAMIC", "AFL_LLVM_NGRAM_SIZE", "AFL_NGRAM_SIZE",
     "AFL_LLVM_NO_RPATH", "AFL_LLVM_NOT_ZERO", "AFL_LLVM_INSTRUMENT_FILE",
     "AFL_LLVM_THREADSAFE_INST", "AFL_LLVM_SKIP_NEVERZERO", "AFL_NO_AFFINITY",
-    "AFL_TRY_AFFINITY", "AFL_LLVM_LTO_DONTWRITEID",
+    "AFL_TRY_AFFINITY", "AFL_LLVM_LTO_DONTWRITEID", "AFL_LLVM_LTO_SKIPINIT",
-    "AFL_LLVM_LTO_SKIPINIT"
+    "AFL_LLVM_LTO_STARTID", "AFL_FUZZER_LOOPCOUNT", "AFL_NO_ARITH",
-    "AFL_LLVM_LTO_STARTID",
+    "AFL_NO_AUTODICT", "AFL_NO_BUILTIN",
-    "AFL_FUZZER_LOOPCOUNT", "AFL_NO_ARITH", "AFL_NO_AUTODICT", "AFL_NO_BUILTIN",
 #if defined USE_COLOR && !defined ALWAYS_COLORED
     "AFL_NO_COLOR", "AFL_NO_COLOUR",
 #endif
-    "AFL_NO_CPU_RED",
+    "AFL_NO_CPU_RED", "AFL_NO_SYNC",
     "AFL_NO_CFG_FUZZING",  // afl.rs rust crate option
     "AFL_NO_CRASH_README", "AFL_NO_FORKSRV", "AFL_NO_UI", "AFL_NO_PYTHON",
     "AFL_NO_STARTUP_CALIBRATION", "AFL_NO_WARN_INSTABILITY",

src/afl-fuzz-run.c

@@ -666,6 +666,8 @@ abort_calibration:
 
 void sync_fuzzers(afl_state_t *afl) {
 
+  if (unlikely(afl->afl_env.afl_no_sync)) { return; }
+
   DIR           *sd;
   struct dirent *sd_ent;
   u32            sync_cnt = 0, synced = 0, entries = 0;

src/afl-fuzz-state.c

@@ -279,6 +279,13 @@ void read_afl_environment(afl_state_t *afl, char **envp) {
             afl->afl_env.afl_final_sync =
                 get_afl_env(afl_environment_variables[i]) ? 1 : 0;
 
+          } else if (!strncmp(env, "AFL_NO_SYNC",
+
+                              afl_environment_variable_len)) {
+
+            afl->afl_env.afl_no_sync =
+                get_afl_env(afl_environment_variables[i]) ? 1 : 0;
+
           } else if (!strncmp(env, "AFL_CUSTOM_MUTATOR_ONLY",
 
                               afl_environment_variable_len)) {

src/afl-fuzz-stats.c

@@ -2487,7 +2487,7 @@ void show_init_stats(afl_state_t *afl) {
 
 }
 
-void update_calibration_time(afl_state_t *afl, u64 *time) {
+inline void update_calibration_time(afl_state_t *afl, u64 *time) {
 
   u64 cur = get_cur_time_us();
   afl->calibration_time_us += cur - *time;
@@ -2495,7 +2495,7 @@ void update_calibration_time(afl_state_t *afl, u64 *time) {
 
 }
 
-void update_trim_time(afl_state_t *afl, u64 *time) {
+inline void update_trim_time(afl_state_t *afl, u64 *time) {
 
   u64 cur = get_cur_time_us();
   afl->trim_time_us += cur - *time;
@@ -2503,7 +2503,7 @@ void update_trim_time(afl_state_t *afl, u64 *time) {
 
 }
 
-void update_sync_time(afl_state_t *afl, u64 *time) {
+inline void update_sync_time(afl_state_t *afl, u64 *time) {
 
   u64 cur = get_cur_time_us();
   afl->sync_time_us += cur - *time;

src/afl-fuzz.c

@@ -335,6 +335,7 @@ static void usage(u8 *argv0, int more_help) {
       "AFL_STATSD_PORT: change default statsd port (default: 8125)\n"
       "AFL_STATSD_TAGS_FLAVOR: set statsd tags format (default: disable tags)\n"
       "                        suported formats: dogstatsd, librato, signalfx, influxdb\n"
+      "AFL_NO_SYNC: disables all syncing\n"
       "AFL_SYNC_TIME: sync time between fuzzing instances (in minutes)\n"
       "AFL_FINAL_SYNC: sync a final time when exiting (will delay the exit!)\n"
       "AFL_NO_CRASH_README: do not create a README in the crashes directory\n"