libxml2:xml: Heap-use-after-free in __xmlRaiseError

Project:
https://gitlab.gnome.org/GNOME/libxml2.git

Detailed Report: https://oss-fuzz.com/testcase?key=5651400406335488

Project: libxml2
Fuzzing Engine: honggfuzz
Fuzz Target: xml
Job Type: honggfuzz_asan_libxml2
Platform Id: linux

Crash Type: Heap-use-after-free READ 2
Crash Address: 0x6020000010f0
Crash State:
__xmlRaiseError
xmlErrValidNode
xmlValidateRef

Sanitizer: address (ASAN)

Recommended Security Severity: High

Regressed: https://oss-fuzz.com/revisions?job=honggfuzz_asan_libxml2&range=202006050251:202006060253

Reproducer Testcase: https://oss-fuzz.com/download?testcase_id=5651400406335488

Issue filed automatically.

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This bug is subject to a 90 day disclosure deadline. If 90 days elapse
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