diff --git a/src/ItemData.cc b/src/ItemData.cc
index a0ff5d53..d21a76d4 100644
--- a/src/ItemData.cc
+++ b/src/ItemData.cc
@@ -647,6 +647,9 @@ bool ItemData::compare_for_sort(const ItemData& a, const ItemData& b) {
 }
 
 ItemData ItemData::from_data(const string& data) {
+  if (data.size() < 2) {
+    throw runtime_error("data is too short");
+  }
   if (data.size() > 0x10) {
     throw runtime_error("data is too long");
   }
@@ -658,6 +661,9 @@ ItemData ItemData::from_data(const string& data) {
   for (size_t z = 12; z < min<size_t>(data.size(), 16); z++) {
     ret.data2[z - 12] = data[z];
   }
+  if (ret.data1[0] > 4) {
+    throw runtime_error("invalid item class");
+  }
   return ret;
 }
 
diff --git a/src/ItemNameIndex.cc b/src/ItemNameIndex.cc
index bd98a053..cfce7f0e 100644
--- a/src/ItemNameIndex.cc
+++ b/src/ItemNameIndex.cc
@@ -371,23 +371,7 @@ ItemData ItemNameIndex::parse_item_description(Version version, const std::strin
       ret = this->parse_item_description_phase(version, desc, true);
     } catch (const exception& e2) {
       try {
-        string data = parse_data_string(desc);
-        if (data.size() < 2) {
-          throw runtime_error("item code too short");
-        }
-        if (data[0] > 4) {
-          throw runtime_error("invalid item class");
-        }
-        if (data.size() > 16) {
-          throw runtime_error("item code too long");
-        }
-
-        if (data.size() <= 12) {
-          memcpy(ret.data1.data(), data.data(), data.size());
-        } else {
-          memcpy(ret.data1.data(), data.data(), 12);
-          memcpy(ret.data2.data(), data.data() + 12, data.size() - 12);
-        }
+        ret = ItemData::from_data(parse_data_string(desc));
       } catch (const exception& ed) {
         if (strcmp(e1.what(), e2.what())) {
           throw runtime_error(string_printf("cannot parse item description \"%s\" in %s (as text 1: %s) (as text 2: %s) (as data: %s)",