OSV-2021-651 Heap-use-after-free in zend_gc_delref

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=33335 Crash type: Heap-use-after-free READ 4 Crash state: zendgcdelref zvaldelrefp zvalptrdtornogc...

OSV-2020-1683 UNKNOWN READ in zend_gc_delref

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=25321 Crash type: UNKNOWN READ Crash state: zendgcdelref zvaldelrefp zvalptrdtornogc...