Bug 1023941 - Part 5: Loader hook to redirect the missing import. r=bsmedberg

--HG--
extra : rebase_source : 7cf2e857f51dcfcc95bb806d49ef13b794f5ba5b

b2g/app/nsBrowserApp.cpp

@@ -25,6 +25,7 @@
 
 #ifdef XP_WIN
 // we want a wmain entry point
+#define XRE_DONT_SUPPORT_XPSP2 // See https://bugzil.la/1023941#c32
 #include "nsWindowsWMain.cpp"
 #define snprintf _snprintf
 #define strcasecmp _stricmp

ipc/ipdl/test/cxx/app/TestIPDL.cpp

@@ -6,6 +6,7 @@
 
 #if defined(XP_WIN)
 #include <windows.h>
+#define XRE_DONT_SUPPORT_XPSP2 // this app doesn't ship
 #include "nsWindowsWMain.cpp"
 #endif
 

js/xpconnect/shell/xpcshell.cpp

@@ -20,6 +20,7 @@
 
 // we want a wmain entry point
 #define XRE_DONT_PROTECT_DLL_LOAD
+#define XRE_DONT_SUPPORT_XPSP2 // xpcshell does not ship
 #define XRE_WANT_ENVIRON
 #include "nsWindowsWMain.cpp"
 #endif

toolkit/xre/WindowsCrtPatch.h

@@ -0,0 +1,146 @@
+/* -*- Mode: C++; tab-width: 40; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * This file works around an incompatibility between Visual Studio 2013's
+ * C Runtime DLL and Windows XP Service Pack 2.
+ *
+ * On XP SP2, msvcr120.dll fails to load, because it has a load-time dependency
+ * on a kernel32 export named GetLogicalProcessorInformation, which is only
+ * available in XP SP3 and newer. Microsoft has declared this to be by design.
+ * See: https://connect.microsoft.com/VisualStudio/feedback/details/811379/
+ *
+ * The CRT calls GetLogicalProcessorInformation only from the concurrency
+ * runtime, which our code does not use. A potential workaround is to 
+ * static-link the CRT into all of our binaries and let the linker drop the
+ * unused API calls. We don't want to take that approach, due to concerns
+ * about binary bloat and jemalloc integration.
+ *
+ * Instead we hook the Windows loader and patch out the missing import.
+ * We intercept ntdll!RtlImageNtHeader, which is a helper API called during
+ * the DLL loading process. We walk the PE image and redirect the
+ * GetLogicalProcessorInformation import to something benign like DebugBreak,
+ * before the loader populates msvcr120.dll's import table.
+ *
+ * This is a fragile hack that only works if we can set up the hook before
+ * Windows tries to load msvcr120.dll. This means that all .exe files:
+ *  1) must static-link the CRT
+ *  2) must delay-load anything with ties to msvcr120.dll (e.g. mozglue.dll)
+ *  3) must not call malloc, because the linker would substitute our mozglue
+ *     replacements, which leads to the CRT loading mozglue before main.
+ * The remainder of our binaries can continue to dynamic-link the CRT.
+ * Assertions enforce that our hooks are installed before msvcr120.dll.
+ */
+
+#ifndef WindowsCrtPatch_h
+#define WindowsCrtPatch_h
+
+#include "nsWindowsDllInterceptor.h"
+#include "mozilla/WindowsVersion.h"
+
+namespace WindowsCrtPatch {
+
+mozilla::WindowsDllInterceptor NtdllIntercept;
+
+typedef PIMAGE_NT_HEADERS (NTAPI *RtlImageNtHeader_func)(HMODULE module);
+static RtlImageNtHeader_func stub_RtlImageNtHeader = 0;
+
+// A helper to simplify the use of Relative Virtual Addresses.
+template <typename T>
+class RVAPtr
+{
+public:
+  RVAPtr(HMODULE module, size_t rva)
+    : _ptr(reinterpret_cast<T*>(reinterpret_cast<char*>(module) + rva)) {}
+  operator T*() { return _ptr; }
+  T* operator ->() { return _ptr; }
+  T* operator ++() { return ++_ptr; }
+
+private:
+  T* _ptr;
+};
+
+void
+PatchModuleImports(HMODULE module, PIMAGE_NT_HEADERS headers)
+{
+  static const WORD MAGIC_DOS = 0x5a4d; // "MZ"
+  static const DWORD MAGIC_PE = 0x4550; // "PE\0\0"
+  RVAPtr<IMAGE_DOS_HEADER> dosStub(module, 0);
+
+  if (!module ||
+      !headers ||
+      dosStub->e_magic != MAGIC_DOS ||
+      headers != RVAPtr<IMAGE_NT_HEADERS>(module, dosStub->e_lfanew) ||
+      headers->Signature != MAGIC_PE ||
+      headers->FileHeader.SizeOfOptionalHeader < sizeof(IMAGE_OPTIONAL_HEADER)) {
+    return;
+  }
+
+  // The format of the import directory is described in:
+  // "An In-Depth Look into the Win32 Portable Executable File Format, Part 2"
+  // http://msdn.microsoft.com/en-us/magazine/cc301808.aspx
+
+  IMAGE_DATA_DIRECTORY* importDirectory =
+    &headers->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT];
+  RVAPtr<IMAGE_IMPORT_DESCRIPTOR> descriptor(module, importDirectory->VirtualAddress);
+
+  for (; descriptor->OriginalFirstThunk; ++descriptor) {
+    RVAPtr<char> importedModule(module, descriptor->Name);
+    if (!stricmp(importedModule, "kernel32.dll")) {
+      RVAPtr<IMAGE_THUNK_DATA> thunk(module, descriptor->OriginalFirstThunk);
+      for (; thunk->u1.AddressOfData; ++thunk) {
+        RVAPtr<IMAGE_IMPORT_BY_NAME> import(module, thunk->u1.AddressOfData);
+        if (!strcmp(import->Name, "GetLogicalProcessorInformation")) {
+          memcpy(import->Name, "DebugBreak", sizeof("DebugBreak"));
+        }
+      }
+    }
+  }
+}
+
+PIMAGE_NT_HEADERS NTAPI
+patched_RtlImageNtHeader(HMODULE module)
+{
+  PIMAGE_NT_HEADERS headers = stub_RtlImageNtHeader(module);
+
+  if (module == GetModuleHandleA("msvcr120.dll")) {
+    PatchModuleImports(module, headers);
+  }
+
+  return headers;
+}
+
+// Non-inline to make the asserts stand out
+MOZ_NEVER_INLINE void
+Init()
+{
+  // If the C Runtime DLL is already loaded, our hooks will be ineffective,
+  // and we will fail to load on XP SP2 when built with Visual Studio 2013.
+  // We assert the absence of these modules on all Windows builds in order to
+  // catch breakage faster.
+  //
+  // If these assertions fail, see the comment at the top of this file for
+  // possible causes. Any changes to the lines below MUST be tested on XP SP2!
+  MOZ_ASSERT(!GetModuleHandleA("mozglue.dll"));
+  MOZ_ASSERT(!GetModuleHandleA("msvcr120.dll"));
+  MOZ_ASSERT(!GetModuleHandleA("msvcr120d.dll"));
+
+  // Temporary until we fully switch over to VS 2013:
+  MOZ_ASSERT(!GetModuleHandleA("msvcr100.dll"));
+  MOZ_ASSERT(!GetModuleHandleA("msvcr100d.dll"));
+
+#if defined(_M_IX86) && defined(_MSC_VER) && _MSC_VER >= 1800
+  if (!mozilla::IsXPSP3OrLater()) {
+    NtdllIntercept.Init("ntdll.dll");
+    NtdllIntercept.AddHook("RtlImageNtHeader",
+                           reinterpret_cast<intptr_t>(patched_RtlImageNtHeader),
+                           reinterpret_cast<void**>(&stub_RtlImageNtHeader));
+  }
+#endif
+}
+
+} // namespace WindowsCrtPatch
+
+#endif // WindowsCrtPatch_h

toolkit/xre/nsWindowsWMain.cpp

@@ -16,6 +16,10 @@
 #include "nsSetDllDirectory.h"
 #endif
 
+#ifndef XRE_DONT_SUPPORT_XPSP2
+#include "WindowsCrtPatch.h"
+#endif
+
 #ifdef __MINGW32__
 
 /* MingW currently does not implement a wide version of the
@@ -76,6 +80,10 @@ FreeAllocStrings(int argc, char **argv)
 
 int wmain(int argc, WCHAR **argv)
 {
+#ifndef XRE_DONT_SUPPORT_XPSP2
+  WindowsCrtPatch::Init();
+#endif
+
 #ifndef XRE_DONT_PROTECT_DLL_LOAD
   mozilla::SanitizeEnvironmentVariables();
   SetDllDirectoryW(L"");

xulrunner/app/nsXULRunnerApp.cpp

@@ -25,6 +25,7 @@
 #include "nsINIParser.h"
 
 #ifdef XP_WIN
+#define XRE_DONT_SUPPORT_XPSP2 // See https://bugzil.la/1023941#c32
 #include "nsWindowsWMain.cpp"
 #endif