OSV-2021-853 Heap-buffer-overflow in jxl::ThreadPool::RunCallState<jxl::ConvertToExternal

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35172 Crash type: Heap-buffer-overflow WRITE 4 Crash state: jxl::ThreadPool::RunCallStatejxl::ConvertToExternal jpegxl::ThreadParallelRunner::ThreadFunc void std::1::threadproxystd::1::tuplestd::1::uniqueptrstd::1::...