fix: Network shutdown (#912)

src/network.sh

@@ -59,9 +59,11 @@ configureDHCP() {
       fi ;;
   esac
 
+  if [[ "$MTU" != "0" ]] && [[ "$MTU" != "1500" ]]; then
     if ! ip link set dev "$VM_NET_TAP" mtu "$MTU"; then
       warn "Failed to set MTU size.."
     fi
+  fi
 
   while ! ip link set "$VM_NET_TAP" up; do
     info "Waiting for MAC address $VM_NET_MAC to become available..."
@@ -197,7 +199,6 @@ configureNAT() {
   fi
 
   # Create a bridge with a static IP for the VM guest
-
   { ip link add dev dockerbridge type bridge ; rc=$?; } || :
 
   if (( rc != 0 )); then
@@ -218,9 +219,11 @@ configureNAT() {
     error "$tuntap" && return 1
   fi
 
+  if [[ "$MTU" != "0" ]] && [[ "$MTU" != "1500" ]]; then
     if ! ip link set dev "$VM_NET_TAP" mtu "$MTU"; then
       warn "Failed to set MTU size.."
     fi
+  fi
 
   GATEWAY_MAC=$(echo "$VM_NET_MAC" | md5sum | sed 's/^\(..\)\(..\)\(..\)\(..\)\(..\).*$/02:\1:\2:\3:\4:\5/')
 
@@ -275,6 +278,22 @@ configureNAT() {
   return 0
 }
 
+closeBridge() {
+
+  local pid="/var/run/dnsmasq.pid"
+  [ -s "$pid" ] && pKill "$(<"$pid")"
+
+  [[ "${NETWORK,,}" == "user"* ]] && return 0
+
+  ip link set "$VM_NET_TAP" down promisc off &> null || true
+  ip link delete "$VM_NET_TAP" &> null || true
+
+  ip link set dockerbridge down &> null || true
+  ip link delete dockerbridge &> null || true
+
+  return 0
+}
+
 closeNetwork() {
 
   if [[ "$DHCP" == [Yy1]* ]]; then
@@ -290,26 +309,16 @@ closeNetwork() {
   exec 30<&- || true
   exec 40<&- || true
 
-  if [[ "$DHCP" == [Yy1]* ]]; then
+  if [[ "$DHCP" != [Yy1]* ]]; then
+
+    closeBridge
+    return 0
+
+  fi
 
   ip link set "$VM_NET_TAP" down || true
   ip link delete "$VM_NET_TAP" || true
 
-  else
-
-    local pid="/var/run/dnsmasq.pid"
-    [ -s "$pid" ] && pKill "$(<"$pid")"
-
-    [[ "${NETWORK,,}" == "user"* ]] && return 0
-
-    ip link set "$VM_NET_TAP" down promisc off || true
-    ip link delete "$VM_NET_TAP" || true
-
-    ip link set dockerbridge down || true
-    ip link delete dockerbridge || true
-
-  fi
-
   return 0
 }
 
@@ -357,6 +366,16 @@ getInfo() {
     MTU=$(cat "/sys/class/net/$VM_NET_DEV/mtu")
   fi
 
+  if [ "$MTU" -gt "1500" ]; then
+    info "MTU size is too large: $MTU, ignoring..." && MTU="0"
+  fi
+
+  if [[ "${ADAPTER,,}" != "virtio-net-pci" ]]; then
+    if [[ "$MTU" != "0" ]] && [[ "$MTU" != "1500" ]]; then
+      warn "MTU size is $MTU, but cannot be set for $ADAPTER adapters!" && MTU="0"
+    fi
+  fi
+
   if [ -z "$VM_NET_MAC" ]; then
     local file="$STORAGE/dsm.mac"
     [ -s "$file" ] && VM_NET_MAC=$(<"$file")
@@ -399,7 +418,10 @@ getInfo
 html "Initializing network..."
 
 if [[ "$DEBUG" == [Yy1]* ]]; then
-  info "Host: $HOST  IP: $IP  Gateway: $GATEWAY  Interface: $VM_NET_DEV  MAC: $VM_NET_MAC  MTU: $MTU"
+  mtu=$(cat "/sys/class/net/$VM_NET_DEV/mtu")
+  line="Host: $HOST  IP: $IP  Gateway: $GATEWAY  Interface: $VM_NET_DEV  MAC: $VM_NET_MAC  MTU: $mtu"
+  [[ "$MTU" != "0" ]] && [[ "$MTU" != "$mtu" ]] && line+=" ($MTU)"
+  info "$line"
   [ -f /etc/resolv.conf ] && grep '^nameserver*' /etc/resolv.conf
   echo
 fi
@@ -442,15 +464,10 @@ else
     # Configure for tap interface
     if ! configureNAT; then
 
+      closeBridge
       NETWORK="user"
       warn "falling back to usermode networking! Performance will be bad and port mapping will not work."
 
-      ip link set "$VM_NET_TAP" down promisc off &> null || true
-      ip link delete "$VM_NET_TAP" &> null || true
-
-      ip link set dockerbridge down &> null || true
-      ip link delete dockerbridge &> null || true
-
     fi
 
   fi
@@ -464,6 +481,7 @@ else
 
 fi
 
-NET_OPTS+=" -device $ADAPTER,romfile=,netdev=hostnet0,mac=$VM_NET_MAC,host_mtu=$MTU,id=net0"
+NET_OPTS+=" -device $ADAPTER,id=net0,netdev=hostnet0,romfile=,mac=$VM_NET_MAC"
+[[ "$MTU" != "0" ]] && [[ "$MTU" != "1500" ]] && NET_OPTS+=",host_mtu=$MTU"
 
 return 0