[XAM] Fixed potential OOB memory write in copy utils

src/xenia/kernel/xam/profile_manager.cc

@@ -499,7 +499,7 @@ bool ProfileManager::CreateAccount(const uint64_t xuid,
   const std::u16string gamertag_u16 = xe::to_utf16(gamertag);
 
   string_util::copy_and_swap_truncating(account.gamertag, gamertag_u16,
-                                        sizeof(account.gamertag));
+                                        xe::countof(account.gamertag));
 
   const bool result = UpdateAccount(xuid, &account);
   DismountProfile(xuid);

src/xenia/kernel/xam/xam_info.cc

@@ -204,8 +204,9 @@ dword_result_t keXamBuildResourceLocator(uint64_t module,
     path = fmt::format(u"section://{:X},{}#{}", (uint32_t)module, container,
                        resource);
   }
+  const uint32_t char_count = buffer_count / sizeof(char16_t);
   xe::string_util::copy_and_swap_truncating(buffer_ptr.as<char16_t*>(), path,
-                                            buffer_count);
+                                            char_count);
   return 0;
 }
 

src/xenia/kernel/xam/xam_locale.cc

@@ -496,7 +496,8 @@ void XFormatDateString(uint64_t filetime, uint32_t buffer_address,
                          static_cast<unsigned>(year_month_day.month()),
                          static_cast<unsigned>(year_month_day.day()),
                          static_cast<int>(year_month_day.year()));
-  xe::string_util::copy_and_swap_truncating(buffer, str, buffer_size);
+  const uint32_t char_count = buffer_size / sizeof(char16_t);
+  xe::string_util::copy_and_swap_truncating(buffer, str, char_count);
 }
 
 void XamFormatDateString_entry(dword_t locale_format, qword_t filetime,
@@ -523,7 +524,8 @@ void XFormatTimeString(uint64_t filetime, uint32_t buffer_address,
 
   auto str = fmt::format(u"{:02d}:{:02d}", time.hours().count(),
                          time.minutes().count());
-  xe::string_util::copy_and_swap_truncating(buffer, str, buffer_size);
+  const uint32_t char_count = buffer_size / sizeof(char16_t);
+  xe::string_util::copy_and_swap_truncating(buffer, str, char_count);
 }
 
 void XamFormatTimeString_entry(dword_t user_index, qword_t filetime,

src/xenia/kernel/xam/xam_ui.cc

@@ -474,7 +474,7 @@ dword_result_t XamShowKeyboardUI_entry(
 
   assert_not_null(overlapped);
 
-  auto buffer_size = static_cast<size_t>(buffer_length) * 2;
+  auto buffer_size = static_cast<size_t>(buffer_length) * sizeof(char16_t);
 
   X_RESULT result;
   if (cvars::headless) {