add cooloff period for rapidly exiting libFuzzer targets
@@ -24,7 +24,7 @@ use tokio::{
select,
sync::{mpsc, Notify},
task,
- time::{sleep, Duration},
+ time::{sleep, Duration, Instant},
};
use uuid::Uuid;
@@ -37,6 +37,9 @@ const PROC_INFO_PERIOD: Duration = Duration::from_secs(30);
// Period of reporting fuzzer-generated runtime stats.
const RUNTIME_STATS_PERIOD: Duration = Duration::from_secs(60);
+// Period for minimum duration between launches of libFuzzer
+const COOLOFF_PERIOD: Duration = Duration::from_secs(10);
+
/// Maximum number of log message to safe in case of libFuzzer failing,
/// arbitrarily chosen
const LOGS_BUFFER_SIZE: usize = 1024;
@@ -160,6 +163,7 @@ impl LibFuzzerFuzzTask {
) -> Result<()> {
let local_input_dir = self.create_local_temp_dir().await?;
loop {
+ let instant = Instant::now();
self.run_fuzzer(&local_input_dir.path(), worker_id, stats_sender)
.await?;
@@ -181,6 +185,13 @@ impl LibFuzzerFuzzTask {
)
})?;
}
+
+ // if libFuzzer is exiting rapidly, give some breathing room to allow the
+ // handles to be reaped.
+ let runtime = instant.elapsed();
+ if runtime < COOLOFF_PERIOD {
+ sleep(COOLOFF_PERIOD - runtime).await;
+ }
}
}
@@ -335,7 +346,7 @@ async fn report_fuzzer_sys_info(
) -> Result<()> {
// Allow for sampling CPU usage.
let mut period = tokio::time::interval_at(
- tokio::time::Instant::now() + PROC_INFO_COLLECTION_DELAY,
+ Instant::now() + PROC_INFO_COLLECTION_DELAY,
PROC_INFO_PERIOD,
);
loop {
