commit beb328cc4c30f852e9ca6042b80994752329380e
author Sanjay Narayanan <sanjay.narayanan@bluerivertech.com> Wed Sep 01 16:24:20 2021 -0700
committer Sanjay Narayanan <sanjay.narayanan@bluerivertech.com> Mon Sep 13 15:57:07 2021 -0700
tree 5ced387aec66e0789d666a9f404a6e1f16511793
parent 9896c7544c62b755785bd4b1e54d54541af65188

Fix use-after-free in log_cat

We were trying to use NodePrinters in the factory after they were
destroyed. Initializing them to outlive the factory addresses this.

Change-Id: I19e5b112fb67ef7d36ff9f885b6497b6abbec313
Signed-off-by: Sanjay Narayanan <sanjay.narayanan@bluerivertech.com>

aos/events/logging/log_cat.cc

diff --git a/aos/events/logging/log_cat.cc b/aos/events/logging/log_cat.cc
index 5a9040e..71293af 100644
--- a/aos/events/logging/log_cat.cc
+++ b/aos/events/logging/log_cat.cc
@@ -364,16 +364,15 @@
 
   aos::FastStringBuilder builder;
 
-  aos::SimulatedEventLoopFactory event_loop_factory(reader.configuration());
-
-  reader.RegisterWithoutStarting(&event_loop_factory);
-
   uint64_t message_print_counter = 0;
 
   std::vector<NodePrinter *> printers;
-  printers.resize(
-      aos::configuration::NodesCount(event_loop_factory.configuration()),
-      nullptr);
+  printers.resize(aos::configuration::NodesCount(reader.configuration()),
+                  nullptr);
+
+  aos::SimulatedEventLoopFactory event_loop_factory(reader.configuration());
+
+  reader.RegisterWithoutStarting(&event_loop_factory);
 
   for (const aos::Node *node :
        aos::configuration::GetNodes(event_loop_factory.configuration())) {