diff --git a/wiretap/catapult_dct2000.c b/wiretap/catapult_dct2000.c
index 39c0eb8c0c..41900eed32 100644
--- a/wiretap/catapult_dct2000.c
+++ b/wiretap/catapult_dct2000.c
@@ -412,7 +412,7 @@ gboolean catapult_dct2000_read(wtap *wth, int *err, gchar **err_info _U_,
             }
 
             /* Add packet entry into table */
-            pkey = g_malloc(sizeof(pkey));
+            pkey = g_malloc(sizeof(*pkey));
             *pkey = this_offset;
             g_hash_table_insert(file_externals->packet_prefix_table, pkey, line_prefix_info);