unit test ensuring that OOB table init allowed on set code; fails on action

libraries/chain/webassembly/wavm.cpp

@@ -144,12 +144,17 @@ std::unique_ptr<wasm_instantiated_module_interface> wavm_runtime::instantiate_mo
       EOS_ASSERT(false, wasm_serialization_error, e.message.c_str());
    }
 
-   eosio::chain::webassembly::common::root_resolver resolver;
-   LinkResult link_result = linkModule(*module, resolver);
-   ModuleInstance *instance = instantiateModule(*module, std::move(link_result.resolvedImports));
-   EOS_ASSERT(instance != nullptr, wasm_exception, "Fail to Instantiate WAVM Module");
+   try {
+      eosio::chain::webassembly::common::root_resolver resolver;
+      LinkResult link_result = linkModule(*module, resolver);
+      ModuleInstance *instance = instantiateModule(*module, std::move(link_result.resolvedImports));
+      EOS_ASSERT(instance != nullptr, wasm_exception, "Fail to Instantiate WAVM Module");
 
-   return std::make_unique<wavm_instantiated_module>(instance, std::move(module), initial_memory);
+      return std::make_unique<wavm_instantiated_module>(instance, std::move(module), initial_memory);
+   }
+   catch(const Runtime::Exception& e) {
+      EOS_THROW(wasm_execution_error, "Failed to stand up WAVM instance: ${m}", ("m", describeExceptionCause(e.cause)));
+   }
 }
 
 void wavm_runtime::immediately_exit_currently_running_module() {

unittests/contracts/test_wasts.hpp

@@ -439,6 +439,38 @@ static const char table_checker_small_wast[] = R"=====(
 )
 )=====";
 
+static const char table_init_oob_wast[] = R"=====(
+(module
+ (type $mahsig (func (param i64) (param i64) (param i64)))
+ (table 1024 anyfunc)
+ (export "apply" (func $apply))
+ (func $apply (param $0 i64) (param $1 i64) (param $2 i64)
+ )
+ (elem (i32.const 1024) $apply)
+)
+)=====";
+
+static const char table_init_oob_smaller_wast[] = R"=====(
+(module
+ (type $mahsig (func (param i64) (param i64) (param i64)))
+ (table 620 anyfunc)
+ (export "apply" (func $apply))
+ (func $apply (param $0 i64) (param $1 i64) (param $2 i64)
+ )
+ (elem (i32.const 700) $apply)
+)
+)=====";
+
+static const char table_init_oob_no_table_wast[] = R"=====(
+(module
+ (type $mahsig (func (param i64) (param i64) (param i64)))
+ (export "apply" (func $apply))
+ (func $apply (param $0 i64) (param $1 i64) (param $2 i64)
+ )
+ (elem (i32.const 0) $apply)
+)
+)=====";
+
 static const char global_protection_none_get_wast[] = R"=====(
 (module
  (export "apply" (func $apply))

unittests/wasm_tests.cpp

@@ -686,6 +686,42 @@ BOOST_FIXTURE_TEST_CASE( table_init_tests, TESTER ) try {
 
 } FC_LOG_AND_RETHROW()
 
+BOOST_FIXTURE_TEST_CASE( table_init_oob, TESTER ) try {
+   create_accounts( {N(tableinitoob)} );
+   produce_block();
+
+   signed_transaction trx;
+   trx.actions.emplace_back(vector<permission_level>{{N(tableinitoob),config::active_name}}, N(tableinitoob), N(), bytes{});
+   trx.actions[0].authorization = vector<permission_level>{{N(tableinitoob),config::active_name}};
+
+    auto pushit_and_expect_fail = [&]() {
+      produce_block();
+      trx.signatures.clear();
+      set_transaction_headers(trx);
+      trx.sign(get_private_key(N(tableinitoob), "active"), control->get_chain_id());
+
+      //the unspecified_exception_code comes from WAVM, which manages to throw a WAVM specific exception
+      // up to where exec_one captures it and doesn't understand it
+      BOOST_CHECK_THROW(push_transaction(trx), eosio::chain::wasm_execution_error);
+   };
+
+   set_code(N(tableinitoob), table_init_oob_wast);
+   produce_block();
+
+   pushit_and_expect_fail();
+   //make sure doing it again didn't lodge something funky in to a cache
+   pushit_and_expect_fail();
+
+   set_code(N(tableinitoob), table_init_oob_smaller_wast);
+   produce_block();
+   pushit_and_expect_fail();
+   pushit_and_expect_fail();
+
+   //an elem w/o a table is a setcode fail though
+   BOOST_CHECK_THROW(set_code(N(tableinitoob), table_init_oob_no_table_wast), eosio::chain::wasm_exception);
+
+} FC_LOG_AND_RETHROW()
+
 BOOST_FIXTURE_TEST_CASE( memory_init_border, TESTER ) try {
    produce_blocks(2);