From 0c11744c50f997b4718eea70a78e347ab4c03335 Mon Sep 17 00:00:00 2001
From: Alex Zenla <alex@mycelium.engineering>
Date: Tue, 6 Feb 2024 06:19:36 +0000
Subject: [PATCH] hypha: protect from panics in the network stack (due to
 interface going away)

---
 hypha/bin/controller.rs  |  9 ++-------
 hypha/src/network/mod.rs | 25 ++++++++++++++++++++++---
 2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/hypha/bin/controller.rs b/hypha/bin/controller.rs
index b8e1268..51b04a9 100644
--- a/hypha/bin/controller.rs
+++ b/hypha/bin/controller.rs
@@ -110,15 +110,10 @@ fn main() -> Result<()> {
         Commands::List { .. } => {
             let containers = controller.list()?;
             let mut table = cli_tables::Table::new();
-            let header = vec!["domain", "uuid", "ipv4", "image"];
+            let header = vec!["uuid", "ipv4", "image"];
             table.push_row(&header)?;
             for container in containers {
-                let row = vec![
-                    container.domid.to_string(),
-                    container.uuid.to_string(),
-                    container.ipv4,
-                    container.image,
-                ];
+                let row = vec![container.uuid.to_string(), container.ipv4, container.image];
                 table.push_row_string(&row)?;
             }
 
diff --git a/hypha/src/network/mod.rs b/hypha/src/network/mod.rs
index 4ad7909..6c650f0 100644
--- a/hypha/src/network/mod.rs
+++ b/hypha/src/network/mod.rs
@@ -1,7 +1,8 @@
 use std::os::fd::AsRawFd;
+use std::panic::UnwindSafe;
 use std::str::FromStr;
-use std::thread;
 use std::time::Duration;
+use std::{panic, thread};
 
 use advmac::MacAddr6;
 use anyhow::{anyhow, Result};
@@ -21,6 +22,7 @@ pub struct NetworkBackend {
 }
 
 unsafe impl Send for NetworkBackend {}
+impl UnwindSafe for NetworkBackend {}
 
 pub struct NetworkService {
     pub network: String,
@@ -66,10 +68,25 @@ impl NetworkBackend {
         }
         let link = link.unwrap();
         handle.link().set(link.header.index).up().execute().await?;
+        tokio::time::sleep(Duration::from_secs(3)).await;
         Ok(())
     }
 
-    pub fn run(&mut self) -> Result<()> {
+    pub fn run(mut self) -> Result<()> {
+        let interface = self.interface.clone();
+        let result = panic::catch_unwind(move || self.run_maybe_panic());
+
+        if result.is_err() {
+            return Err(anyhow!(
+                "network backend for interface {} encountered an error and is now shutdown",
+                interface
+            ));
+        }
+
+        result.unwrap()
+    }
+
+    fn run_maybe_panic(&mut self) -> Result<()> {
         let mac = MacAddr6::random();
         let mac = HardwareAddress::Ethernet(EthernetAddress(mac.to_array()));
         let config = Config::new(mac);
@@ -128,14 +145,16 @@ impl NetworkService {
                 spawned.push(name);
             }
 
-            sleep(Duration::from_secs(5)).await;
+            sleep(Duration::from_secs(2)).await;
         }
     }
 
     async fn add_network_backend(&mut self, interface: &str) -> Result<()> {
         let interface = interface.to_string();
         let mut network = NetworkBackend::new(&interface, &[&self.network])?;
+        info!("initializing network backend for interface {}", interface);
         network.init().await?;
+        tokio::time::sleep(Duration::from_secs(1)).await;
         info!("spawning network backend for interface {}", interface);
         thread::spawn(move || {
             if let Err(error) = network.run() {