[HOTFIX] Resolve race condition in exit signal

- Swaps to SIGCHLD for termination
- Switch to Ordering::SeqCst

bimini-core/src/proc/controller.rs

@@ -74,9 +74,9 @@ impl Controller {
             None,
         )?;
 
-        while sf_runlock.load(Ordering::Relaxed) {
+        while sf_runlock.load(Ordering::SeqCst) {
             match signal_config.parent_signals().wait() {
-                Ok(signal) if sf_runlock.load(Ordering::Relaxed) => {
+                Ok(signal) if sf_runlock.load(Ordering::SeqCst) => {
                     tracing::info!("Passing signal to child: {signal}");
 
                     signal::kill(child_pid, signal).map_err(|eno| {
@@ -115,7 +115,7 @@ impl Controller {
             ));
         }
 
-        self.sf_runlock.store(true, Ordering::Release);
+        self.sf_runlock.store(true, Ordering::SeqCst);
 
         let runlock_clone = Arc::clone(&self.sf_runlock);
         let signal_config = self.signal_config.clone();
@@ -215,7 +215,7 @@ impl Controller {
                 tracing::trace!("Received child status code: {rc}. Cleaning up");
                 if let Some(signal_forwarder) = self.signal_forwarder {
                     tracing::trace!("Releasing signal_forwarding loop runlock");
-                    self.sf_runlock.store(false, Ordering::Release);
+                    self.sf_runlock.swap(false, Ordering::SeqCst);
 
                     tracing::trace!("Sending final SIGTERM to signal_forwarding thread");
                     signal::kill(unistd::Pid::from_raw(0), signal::SIGCHLD)?;