diff --git a/toolkit/components/remote/nsDBusRemoteService.cpp b/toolkit/components/remote/nsDBusRemoteService.cpp
index 7cd9b53ed446..21336fb1b60e 100644
--- a/toolkit/components/remote/nsDBusRemoteService.cpp
+++ b/toolkit/components/remote/nsDBusRemoteService.cpp
@@ -186,6 +186,9 @@ nsDBusRemoteService::Startup(const char* aAppName, const char* aProfileName)
   nsAutoCString busName;
   busName = nsPrintfCString("org.mozilla.%s.%s", mAppName.get(),
                                                  profileName.get());
+  if (busName.Length() > DBUS_MAXIMUM_NAME_LENGTH)
+    busName.Truncate(DBUS_MAXIMUM_NAME_LENGTH);
+
   DBusError err;
   dbus_error_init(&err);
   dbus_bus_request_name(mConnection, busName.get(),
diff --git a/widget/xremoteclient/DBusRemoteClient.cpp b/widget/xremoteclient/DBusRemoteClient.cpp
index 2ca1cafa9a2a..c85c5b868b6f 100644
--- a/widget/xremoteclient/DBusRemoteClient.cpp
+++ b/widget/xremoteclient/DBusRemoteClient.cpp
@@ -133,6 +133,9 @@ DBusRemoteClient::GetRemoteDestinationName(const char *aProgram,
 
     aDestinationName = nsPrintfCString("org.mozilla.%s.%s", aProgram,
                                                             profileName.get());
+    if (aDestinationName.Length() > DBUS_MAXIMUM_NAME_LENGTH)
+      aDestinationName.Truncate(DBUS_MAXIMUM_NAME_LENGTH);
+
     return true;
   }
 }