[wasm] Fix error printing in streaming fuzzer

The error message held in {CompilationResult} was not null-terminated,
leading to ASan complaints. Just store it in a {std::string} and use
{c_str()} to get a properly null-terminated C-string.

Drive-by: Enable execution of the fuzzer tests.

R=ahaas@chromium.org

Bug: chromium:1334548, v8:12922
Change-Id: Iafcfd5ce77e49e2aa1ff0910d8718bcd51f83662
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695356
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81020}

test/fuzzer/testcfg.py

@@ -8,16 +8,17 @@ from testrunner.local import testsuite
 from testrunner.objects import testcase
 
 SUB_TESTS = [
-  'inspector',
-  'json',
-  'parser',
-  'regexp',
-  'regexp_builtins',
-  'multi_return',
-  'wasm',
-  'wasm_async',
-  'wasm_code',
-  'wasm_compile',
+    'inspector',
+    'json',
+    'parser',
+    'regexp',
+    'regexp_builtins',
+    'multi_return',
+    'wasm',
+    'wasm_async',
+    'wasm_code',
+    'wasm_compile',
+    'wasm_streaming',
 ]
 
 class VariantsGenerator(testsuite.VariantsGenerator):

test/fuzzer/wasm-streaming.cc

@@ -22,14 +22,15 @@ struct CompilationResult {
   MOVE_ONLY_WITH_DEFAULT_CONSTRUCTORS(CompilationResult);
 
   bool failed = false;
-  base::OwnedVector<const char> error_message;
+  std::string error_message;
 
   // If successful:
   uint32_t imported_functions = 0;
   uint32_t declared_functions = 0;
 
-  static CompilationResult ForFailure(base::Vector<const char> error_message) {
-    return {true, base::OwnedVector<const char>::Of(error_message)};
+  static CompilationResult ForFailure(std::string error_message) {
+    DCHECK(!error_message.empty());
+    return {true, std::move(error_message)};
   }
 
   static CompilationResult ForSuccess(const WasmModule* module) {
@@ -107,8 +108,7 @@ CompilationResult CompileStreaming(v8_fuzzer::FuzzerSupport* support,
     }
 
     if (resolver->failed()) {
-      return CompilationResult::ForFailure(
-          base::VectorOf(resolver->error_message()));
+      return CompilationResult::ForFailure(resolver->error_message());
     }
 
     result = CompilationResult::ForSuccess(resolver->native_module()->module());
@@ -136,8 +136,7 @@ CompilationResult CompileSync(Isolate* isolate, WasmFeatures enabled_features,
            ->SyncCompile(isolate, enabled_features, &thrower,
                          ModuleWireBytes{data})
            .ToHandle(&module_object)) {
-    auto result =
-        CompilationResult::ForFailure(base::CStrVector(thrower.error_msg()));
+    auto result = CompilationResult::ForFailure(thrower.error_msg());
     thrower.Reset();
     return result;
   }
@@ -173,8 +172,8 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
 
   if (streaming_result.failed != sync_result.failed) {
     const char* error_msg = streaming_result.failed
-                                ? streaming_result.error_message.begin()
-                                : sync_result.error_message.begin();
+                                ? streaming_result.error_message.c_str()
+                                : sync_result.error_message.c_str();
     FATAL(
         "Streaming compilation did%s fail, sync compilation did%s. "
         "Error message: %s\n",