netd: make BandwidthController startup failures terminal

Bug: 235778483
Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Ic6ddf0ca1cda26c27be3bbdbebfde64b02dc2c83

1 files changed, 9 insertions, 1 deletions

diff --git a/server/Controllers.cpp b/server/Controllers.cpp
index 0df6b0ee..00ee186d 100644
--- a/server/Controllers.cpp
+++ b/server/Controllers.cpp
@@ -277,7 +277,15 @@ void Controllers::init() {
     initIptablesRules();
     Stopwatch s;
 
-    bandwidthCtrl.enableBandwidthControl();
+    if (int ret = bandwidthCtrl.enableBandwidthControl()) {
+        gLog.error("Failed to initialize BandwidthController (%s)", strerror(-ret));
+        // A failure to init almost definitely means that iptables failed to load
+        // our static ruleset, which then basically means network accounting will not work.
+        // As such simply exit netd.  This may crash loop the system, but by failing
+        // to bootup we will trigger rollback and thus this offers us protection against
+        // a mainline update breaking things.
+        exit(1);
+    }
     gLog.info("Enabling bandwidth control: %" PRId64 "us", s.getTimeAndResetUs());
 
     if (int ret = RouteController::Init(NetworkController::LOCAL_NET_ID)) {