4 files changed, 13 insertions, 3 deletions
diff --git a/src/afl-fuzz-run.c b/src/afl-fuzz-run.c
index 4e2cceff..6a0da6ab 100644
--- a/src/afl-fuzz-run.c
+++ b/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;
diff --git a/src/afl-fuzz-state.c b/src/afl-fuzz-state.c
index 333d57b2..a1c1e30c 100644
--- a/src/afl-fuzz-state.c
+++ b/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)) {
diff --git a/src/afl-fuzz-stats.c b/src/afl-fuzz-stats.c
index eafeebba..609b11e4 100644
--- a/src/afl-fuzz-stats.c
+++ b/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;
diff --git a/src/afl-fuzz.c b/src/afl-fuzz.c
index 70ab983c..0f6216c4 100644
--- a/src/afl-fuzz.c
+++ b/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"