Bug 1270686. Log all dlls ever loaded. r=aklotz

This is a temporary patch to try to figure out if a dll is being unloaded that we still need.

mozglue/build/WindowsDllBlocklist.cpp

@@ -17,10 +17,13 @@
 #include <windows.h>
 #include <winternl.h>
 #include <io.h>
+#define PSAPI_VERSION 1
+#include <psapi.h>
 
 #pragma warning( push )
 #pragma warning( disable : 4275 4530 ) // See msvc-stl-wrapper.template.h
 #include <map>
+#include <vector>
 #pragma warning( pop )
 
 #include "nsAutoPtr.h"
@@ -543,11 +546,15 @@ static wchar_t* lastslash(wchar_t* s, int len)
   return nullptr;
 }
 
+#ifdef NIGHTLY_BUILD
+static std::vector<DllLoadInfo> gDllLoadInfos;
+static LoadCallBackFn gLoadInfoCallback;
+#endif
+
 static NTSTATUS NTAPI
 patched_LdrLoadDll (PWCHAR filePath, PULONG flags, PUNICODE_STRING moduleFileName, PHANDLE handle)
 {
   // We have UCS2 (UTF16?), we want ASCII, but we also just want the filename portion
-#define DLLNAME_MAX 128
   char dllName[DLLNAME_MAX+1];
   wchar_t *dll_part;
   char *dot;
@@ -735,14 +742,41 @@ continue_loading:
       return STATUS_DLL_NOT_FOUND;
     }
   }
-
-  return stub_LdrLoadDll(filePath, flags, moduleFileName, handle);
+  NTSTATUS ret = stub_LdrLoadDll(filePath, flags, moduleFileName, handle);
+#if defined(NIGHTLY_BUILD) && !defined(_WIN64)
+  if (!ret) {
+      MODULEINFO moduleInfo;
+      if (GetModuleInformation(GetCurrentProcess(), *(HMODULE*)handle, &moduleInfo, sizeof(moduleInfo))) {
+          DllLoadInfo info;
+          strcpy(info.name, dllName);
+          info.lpBaseOfDll = moduleInfo.lpBaseOfDll;
+          info.SizeOfImage = moduleInfo.SizeOfImage;
+          if (gLoadInfoCallback) {
+            gLoadInfoCallback(info);
+          } else {
+            gDllLoadInfos.push_back(info);
+          }
+      }
+  }
+#endif
+  return ret;
 }
 
 WindowsDllInterceptor NtDllIntercept;
 
 } // namespace
 
+#ifdef NIGHTLY_BUILD
+MFBT_API void
+RegisterDllLoadCallback(LoadCallBackFn aCallback) {
+  gLoadInfoCallback = aCallback;
+  for (DllLoadInfo &info : gDllLoadInfos) {
+    aCallback(info);
+  }
+  //gDllLoadInfos.clear();
+}
+#endif
+
 MFBT_API void
 DllBlocklist_Initialize()
 {

mozglue/build/WindowsDllBlocklist.h

@@ -34,5 +34,17 @@ class MOZ_RAII AutoSetXPCOMLoadOnMainThread
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 
+#define DLLNAME_MAX 128
+#ifdef NIGHTLY_BUILD
+struct DllLoadInfo
+{
+  char name[DLLNAME_MAX+1];
+  LPVOID lpBaseOfDll;
+  DWORD SizeOfImage;
+};
+typedef void (*LoadCallBackFn)(DllLoadInfo&);
+MFBT_API void RegisterDllLoadCallback(LoadCallBackFn);
+#endif // NIGHTLY_BUILD
+
 #endif // defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64))
 #endif // mozilla_windowsdllblocklist_h

mozglue/build/moz.build

@@ -52,6 +52,7 @@ if not CONFIG['JS_STANDALONE']:
         ]
         DISABLE_STL_WRAPPING = True
         OS_LIBS += [
+            'psapi',
             'version',
         ]
 

toolkit/crashreporter/nsExceptionHandler.cpp

@@ -14,6 +14,7 @@
 #include "mozilla/Services.h"
 #include "nsIObserverService.h"
 #include "mozilla/unused.h"
+#include "mozilla/ScopeExit.h"
 #include "mozilla/Snprintf.h"
 #include "mozilla/SyncRunnable.h"
 #include "mozilla/TimeStamp.h"
@@ -1437,9 +1438,30 @@ ChildFilter(void* context)
   return result;
 }
 
+#if defined(XP_WIN) && defined(NIGHTLY_BUILD)
+static void DllLoadCallback(DllLoadInfo& info)
+{
+  nsAutoCString note;
+  note.AppendPrintf("%s-%p-%x\n", info.name, info.lpBaseOfDll, info.SizeOfImage);
+
+  CrashReporter::AppendAppNotesToCrashReport(note);
+}
+
+static void EmptyDllLoadCallback(DllLoadInfo& info)
+{
+}
+
+#endif
+
+
 nsresult SetExceptionHandler(nsIFile* aXREDirectory,
                              bool force/*=false*/)
 {
+#if defined(XP_WIN) && defined(NIGHTLY_BUILD)
+  auto dllCallbackGuard = MakeScopeExit([] {
+                                        RegisterDllLoadCallback(EmptyDllLoadCallback);
+                                        });
+#endif
   if (gExceptionHandler)
     return NS_ERROR_ALREADY_INITIALIZED;
 
@@ -1674,6 +1696,11 @@ nsresult SetExceptionHandler(nsIFile* aXREDirectory,
 
   mozalloc_set_oom_abort_handler(AnnotateOOMAllocationSize);
 
+#if defined(XP_WIN) && defined(NIGHTLY_BUILD)
+  dllCallbackGuard.release();
+  RegisterDllLoadCallback(DllLoadCallback);
+#endif
+
   return NS_OK;
 }
 

toolkit/crashreporter/test/unit/test_crashreporter_crash.js

@@ -45,7 +45,10 @@ function run_test()
            function(mdump, extra) {
              do_check_eq(extra.TestKey, "TestValue");
              do_check_eq(extra["\u2665"], "\u{1F4A9}");
-             do_check_eq(extra.Notes, "JunkMoreJunk");
+             // we spam the crash dumps with dlls loading so temporarily disable
+             // this check on windows
+             if (!is_windows)
+               do_check_eq(extra.Notes, "JunkMoreJunk");
              do_check_true(!("TelemetrySessionId" in extra));
            });
 }