Bug 180319 – Wasm::ModuleInformation leaks

• Status: NEW
• Component: WebAssembly

[Alexey Proskuryakov]

I'm getting a reproducible leak on WebKit regression tests.

run-webkit-tests -1 --leaks --no-retry --no-build --no-show --no-sample --debug-rwt-logging http/tests/security/contentSecurityPolicy/WebAssembly-blocked-in-subframe.html --repeat 10

JSC::webAssemblyValidateFunc(JSC::ExecState*) WebAssemblyPrototype.cpp:227 |
JSC::Wasm::BBQPlan::BBQPlan(JSC::Wasm::Context*, unsigned char const*, unsigned long, JSC::Wasm::BBQPlan::AsyncWork, WTF::RefPtr<WTF::SharedTask<void (JSC::Wasm::Plan&)> >&&) WasmBBQPlan.cpp:72 |
JSC::Wasm::BBQPlan::BBQPlan(JSC::Wasm::Context*, unsigned char const*, unsigned long, JSC::Wasm::BBQPlan::AsyncWork, WTF::RefPtr<WTF::SharedTask<void (JSC::Wasm::Plan&)> >&&) WasmBBQPlan.cpp:68 |
JSC::Wasm::Plan::Plan(JSC::Wasm::Context*, unsigned char const*, unsigned long, WTF::RefPtr<WTF::SharedTask<void (JSC::Wasm::Plan&)> >&&) WasmPlan.cpp:68 | JSC::Wasm::ModuleInformation::ModuleInformation(WTF::Vector<unsigned char, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc>&&) WasmModuleInformation.cpp:39 |
JSC::Wasm::ModuleInformation::ModuleInformation(WTF::Vector<unsigned char, 0ul, WTF::CrashOnOverflow, 16ul, WTF::FastMalloc>&&) WasmModuleInformation.cpp:37 |
WTF::ThreadSafeRefCountedBase::operator new(unsigned long) ThreadSafeRefCounted.h:36

[Radar WebKit Bug Importer]

<rdar://problem/35816264>

[JF Bastien]

Interesting, will look into it. I know the GC was retaining WebAssembly modules a bit ago (which themselves retain WasmModuleInformation), I wonder if that's the problem or if we don't ref properly. If it's the former then we have to figure out where we're missing a stack cleanup.

[Alexey Proskuryakov]

This is an actual leak (memory without any pointers to it).