diff --git a/libraries/chain/webassembly/action.cpp b/libraries/chain/webassembly/action.cpp
index 307ddafe6b..4ac120d499 100644
--- a/libraries/chain/webassembly/action.cpp
+++ b/libraries/chain/webassembly/action.cpp
@@ -5,9 +5,8 @@
 namespace eosio { namespace chain { namespace webassembly {
    int32_t interface::read_action_data(legacy_span<char> memory) const {
       auto s = context.get_action().data.size();
-      if( memory.size() == 0 ) return s;
-
       auto copy_size = std::min( static_cast<size_t>(memory.size()), s );
+      if( copy_size == 0 ) return s;
       std::memcpy( memory.data(), context.get_action().data.data(), copy_size );
 
       return copy_size;