Bug 927944 - Annotate crash reports with a list of DLLs that were blocked via the windows blocklist. Also fix the blocklist to recognize forward-slash as a path delimiter, r=ehsan

--HG--
extra : rebase_source : 5cbff13357fe96c5a86b5511a58b69176aa71817

toolkit/crashreporter/nsExceptionHandler.cpp

@@ -222,6 +222,11 @@ static const char kIsGarbageCollectingParameter[] = "IsGarbageCollecting=";
 static const int kIsGarbageCollectingParameterLen =
   sizeof(kIsGarbageCollectingParameter)-1;
 
+#ifdef XP_WIN
+static const char kBlockedDllsParameter[] = "BlockedDllList=";
+static const int kBlockedDllsParameterLen = sizeof(kBlockedDllsParameter) - 1;
+#endif
+
 // this holds additional data sent via the API
 static Mutex* crashReporterAPILock;
 static Mutex* notesFieldLock;
@@ -540,6 +545,9 @@ bool MinidumpCallback(
         WriteFile(hFile, isGarbageCollecting ? "1" : "0", 1, &nBytes, nullptr);
         WriteFile(hFile, "\n", 1, &nBytes, nullptr);
       }
+      WriteFile(hFile, kBlockedDllsParameter, kBlockedDllsParameterLen, &nBytes, nullptr);
+      WriteBlockedDlls(hFile);
+      WriteFile(hFile, "\n", 1, &nBytes, nullptr);
 
       // Try to get some information about memory.
       MEMORYSTATUSEX statex;

toolkit/crashreporter/nsExceptionHandler.h

@@ -44,6 +44,11 @@ nsresult AppendAppNotesToCrashReport(const nsACString& data);
 
 nsresult SetGarbageCollecting(bool collecting);
 
+#ifdef XP_WIN
+// Implemented by the blocklist, this method writes the blocklist annotation
+void WriteBlockedDlls(HANDLE file);
+#endif
+
 nsresult SetRestartArgs(int argc, char** argv);
 nsresult SetupExtraData(nsIFile* aAppDataDirectory,
                         const nsACString& aBuildID);

toolkit/xre/nsWindowsDllBlocklist.cpp

@@ -23,7 +23,7 @@
 
 using namespace mozilla;
 
-#if defined(MOZ_CRASHREPORTER) && !defined(NO_BLOCKLIST_CRASHREPORTER)
+#ifdef MOZ_CRASHREPORTER
 #include "nsExceptionHandler.h"
 #endif
 
@@ -224,6 +224,10 @@ CheckASLR(const wchar_t* path)
   return retval;
 }
 
+// This lock protects both the reentrancy sentinel and the crash reporter
+// data structures.
+static CRITICAL_SECTION sLock;
+
 /**
  * Some versions of Windows call LoadLibraryEx to get the version information
  * for a DLL, which causes our patched LdrLoadDll implementation to re-enter
@@ -270,16 +274,98 @@ public:
   }
 
 private:
-  static CRITICAL_SECTION sLock;
   static std::map<DWORD, const char*>* sThreadMap;
 
   const char* mPreviousDllName;
   bool mReentered;
 };
 
-CRITICAL_SECTION ReentrancySentinel::sLock;
 std::map<DWORD, const char*>* ReentrancySentinel::sThreadMap;
 
+/**
+ * This is a linked list of DLLs that have been blocked. It doesn't use
+ * mozilla::LinkedList because this is an append-only list and doesn't need
+ * to be doubly linked.
+ */
+class DllBlockSet
+{
+public:
+  static void Add(const char* name, unsigned long long version);
+
+  // Write the list of blocked DLLs to a file HANDLE. This method is run after
+  // a crash occurs and must therefore not use the heap, etc.
+  static void Write(HANDLE file);
+
+private:
+  DllBlockSet(const char* name, unsigned long long version)
+    : mName(name)
+    , mVersion(version)
+    , mNext(nullptr)
+  {
+  }
+
+  const char* mName; // points into the sWindowsDllBlocklist string
+  unsigned long long mVersion;
+  DllBlockSet* mNext;
+
+  static DllBlockSet* gFirst;
+};
+
+DllBlockSet* DllBlockSet::gFirst;
+
+void
+DllBlockSet::Add(const char* name, unsigned long long version)
+{
+  EnterCriticalSection(&sLock);
+  for (DllBlockSet* b = gFirst; b; b = b->mNext) {
+    if (0 == strcmp(b->mName, name) && b->mVersion == version) {
+      LeaveCriticalSection(&sLock);
+      return;
+    }
+  }
+  // Not already present
+  DllBlockSet* n = new DllBlockSet(name, version);
+  n->mNext = gFirst;
+  gFirst = n;
+  LeaveCriticalSection(&sLock);
+}
+
+void
+DllBlockSet::Write(HANDLE file)
+{
+  EnterCriticalSection(&sLock);
+  DWORD nBytes;
+
+  // Because this method is called after a crash occurs, and uses heap memory,
+  // protect this entire block with a structured exception handler.
+  __try {
+    for (DllBlockSet* b = gFirst; b; b = b->mNext) {
+      // write name[,v.v.v.v];
+      WriteFile(file, b->mName, strlen(b->mName), &nBytes, nullptr);
+      if (b->mVersion != -1) {
+        WriteFile(file, ",", 1, &nBytes, nullptr);
+        uint16_t parts[4];
+        parts[0] = b->mVersion >> 48;
+        parts[1] = (b->mVersion >> 32) & 0xFFFF;
+        parts[2] = (b->mVersion >> 16) & 0xFFFF;
+        parts[3] = b->mVersion & 0xFFFF;
+        for (int p = 0; p < 4; ++p) {
+          char buf[32];
+          ltoa(parts[p], buf, 10);
+          WriteFile(file, buf, strlen(buf), &nBytes, nullptr);
+          if (p != 3) {
+            WriteFile(file, ".", 1, &nBytes, nullptr);
+          }
+        }
+      }
+      WriteFile(file, ";", 1, &nBytes, nullptr);
+    }
+  }
+  __except (EXCEPTION_EXECUTE_HANDLER) { }
+
+  LeaveCriticalSection(&sLock);
+}
+
 static
 wchar_t* getFullPath (PWCHAR filePath, wchar_t* fname)
 {
@@ -308,6 +394,17 @@ wchar_t* getFullPath (PWCHAR filePath, wchar_t* fname)
   return full_fname;
 }
 
+// No builtin function to find the last character matching a set
+static wchar_t* lastslash(wchar_t* s, int len)
+{
+  for (wchar_t* c = s + len - 1; c >= s; --c) {
+    if (*c == L'\\' || *c == L'/') {
+      return c;
+    }
+  }
+  return nullptr;
+}
+
 static NTSTATUS NTAPI
 patched_LdrLoadDll (PWCHAR filePath, PULONG flags, PUNICODE_STRING moduleFileName, PHANDLE handle)
 {
@@ -334,7 +431,7 @@ patched_LdrLoadDll (PWCHAR filePath, PULONG flags, PUNICODE_STRING moduleFileNam
     goto continue_loading;
   }
 
-  dll_part = wcsrchr(fname, L'\\');
+  dll_part = lastslash(fname, len);
   if (dll_part) {
     dll_part = dll_part + 1;
     len -= dll_part - fname;
@@ -400,6 +497,8 @@ patched_LdrLoadDll (PWCHAR filePath, PULONG flags, PUNICODE_STRING moduleFileNam
       goto continue_loading;
     }
 
+    unsigned long long fVersion = ALL_VERSIONS;
+
     if (info->maxVersion != ALL_VERSIONS) {
       ReentrancySentinel sentinel(dllName);
       if (sentinel.BailOut()) {
@@ -426,7 +525,7 @@ patched_LdrLoadDll (PWCHAR filePath, PULONG flags, PUNICODE_STRING moduleFileNam
         if (GetFileVersionInfoW(full_fname, 0, infoSize, infoData) &&
             VerQueryValueW(infoData, L"\\", (LPVOID*) &vInfo, &vInfoLen))
         {
-          unsigned long long fVersion =
+          fVersion =
             ((unsigned long long)vInfo->dwFileVersionMS) << 32 |
             ((unsigned long long)vInfo->dwFileVersionLS);
 
@@ -440,6 +539,7 @@ patched_LdrLoadDll (PWCHAR filePath, PULONG flags, PUNICODE_STRING moduleFileNam
 
     if (!load_ok) {
       printf_stderr("LdrLoadDll: Blocking load of '%s' -- see http://www.mozilla.com/en-US/blocklist/\n", dllName);
+      DllBlockSet::Add(info->name, fVersion);
       return STATUS_DLL_NOT_FOUND;
     }
   }
@@ -485,9 +585,17 @@ XRE_SetupDllBlocklist()
     printf_stderr ("LdrLoadDll hook failed, no dll blocklisting active\n");
 #endif
 
-#if defined(MOZ_CRASHREPORTER) && !defined(NO_BLOCKLIST_CRASHREPORTER)
+#ifdef MOZ_CRASHREPORTER
   if (!ok) {
     CrashReporter::AppendAppNotesToCrashReport(NS_LITERAL_CSTRING("DllBlockList Failed\n"));
   }
 #endif
 }
+
+#ifdef MOZ_CRASHREPORTER
+void
+CrashReporter::WriteBlockedDlls(HANDLE file)
+{
+  DllBlockSet::Write(file);
+}
+#endif