Instrument setup.exe in the SyzyAsan builds.

chrome/installer/setup/setup_main.cc

Index: chrome/installer/setup/setup_main.cc
diff --git a/chrome/installer/setup/setup_main.cc b/chrome/installer/setup/setup_main.cc
index b8d66b6b4d596eb278d0ee5245f344064b7ba2fe..6b80ef657f7451089ed5704e9540adc4c67e85c8 100644
--- a/chrome/installer/setup/setup_main.cc
+++ b/chrome/installer/setup/setup_main.cc
@@ -82,6 +82,10 @@
 #include "components/crash/content/app/run_as_crashpad_handler_win.h"
 #include "content/public/common/content_switches.h"
 
+#if defined(SYZYASAN)
+#include "base/debug/asan_invalid_access.h"
+#endif
+
 using installer::InstallerState;
 using installer::InstallationState;
 using installer::MasterPreferences;
@@ -1042,6 +1046,21 @@ bool HandleNonInstallCmdLineOptions(const base::FilePath& setup_exe,
         cmd_line.GetSwitchValueNative(
             installer::switches::kSetDisplayVersionValue));
     *exit_code = OverwriteDisplayVersions(registry_product, registry_value);
+#if defined(SYZYASAN)
+  } else if (cmd_line.HasSwitch(installer::switches::kInduceAsanCrash)) {
+    std::string crash_type =
+        cmd_line.GetSwitchValueASCII(installer::switches::kInduceAsanCrash);
+    if (crash_type == installer::switches::kAsanUseAfterFree) {
+      base::debug::AsanHeapUseAfterFree();
+    } else if (crash_type == installer::switches::kAsanHeapOverflow) {
+      base::debug::AsanHeapOverflow();
+    } else if (crash_type == installer::switches::kAsanHeapUnderflow) {
+      base::debug::AsanHeapUnderflow();
+    } else {
+      LOG(ERROR) << "Invalid Asan error type: " << crash_type;
+      handled = false;
+    }
+#endif
   } else {
     handled = false;
   }
@@ -1049,6 +1068,24 @@ bool HandleNonInstallCmdLineOptions(const base::FilePath& setup_exe,
   return handled;
 }
 
+#if defined(SYZYASAN)
+// Initialize the SyzyAsan crash reporter. This should only be called once the
+// crash reporter has been initialized. There should be only one call to this
+// function.
+void SetupSyzyAsan() {
+  using SyzyAsanInitializeCrashReporterFn = VOID(WINAPI*)();
+  HMODULE syzyasan_handle = ::GetModuleHandle(L"syzyasan_rtl.dll");
+  if (!syzyasan_handle)
+    return;
+
+  SyzyAsanInitializeCrashReporterFn syzyasan_init_crash_reporter =
+      reinterpret_cast<SyzyAsanInitializeCrashReporterFn>(
+          ::GetProcAddress(syzyasan_handle, "asan_InitializeCrashReporter"));
+  if (syzyasan_init_crash_reporter)
+    syzyasan_init_crash_reporter();
+}
+#endif
+
 }  // namespace
 
 namespace installer {
@@ -1364,6 +1401,10 @@ int WINAPI wWinMain(HINSTANCE instance, HINSTANCE prev_instance,
   installer::SetInitialCrashKeys(installer_state);
   installer::SetCrashKeysFromCommandLine(cmd_line);
 
+#if defined(SYZYASAN)
+  SetupSyzyAsan();
+#endif
+
   // Make sure the process exits cleanly on unexpected errors.
   base::EnableTerminationOnHeapCorruption();
   base::EnableTerminationOnOutOfMemory();