SEGV found in InsertFirstChild

[Anza2001]

Hi，
UBSAN reported SEGV in InsertFirstChild.

==12==ERROR: UndefinedBehaviorSanitizer: SEGV on unknown address 0x000000000008 (pc 0x5577ea17c682 bp 0x7ffd8d604130 sp 0x7ffd8d604120 T12)
==12==The signal is caused by a READ memory access.
==12==Hint: address points to the zero page.
    #0 0x5577ea17c682 in tinyxml2::XMLNode::InsertFirstChild(tinyxml2::XMLNode*) /src/tinyxml2/tinyxml2.cpp:966:29
    #1 0x5577ea17a2e8 in LLVMFuzzerTestOneInput /src/xmltest_tinyxml2_968.cpp:19:11
    #2 0x5577ea0dc830 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:614:13
    #3 0x5577ea0dc055 in fuzzer::Fuzzer::RunOne(unsigned char const*, unsigned long, bool, fuzzer::InputInfo*, bool, bool*) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:516:7
    #4 0x5577ea0dd835 in fuzzer::Fuzzer::MutateAndTestOne() /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:760:19
    #5 0x5577ea0de5c5 in fuzzer::Fuzzer::Loop(std::__Fuzzer::vector<fuzzer::SizedFile, std::__Fuzzer::allocator<fuzzer::SizedFile>>&) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:905:5
    #6 0x5577ea0cd40b in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:914:6
    #7 0x5577ea0f87e2 in main /src/llvm-project/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20:10
    #8 0x7fac49c0f082 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x24082) (BuildId: 0702430aef5fa3dda43986563e9ffcc47efbd75e)
    #9 0x5577ea0bfc8d in _start (/out/xmltest_tinyxml2_968+0x20c8d)
==12==ABORTING
MS: 4 CMP-CopyPart-ShuffleBytes-ChangeByte- DE: "<!"-; base unit: adc83b19e793491b1c6ea0fd8b46cd9f32e592fc
0x3c,0x21,0x3e,
<!>
artifact_prefix='./'; Test unit written to ./crash-5af51d708183128d272179d551c344b7a643044c
Base64: PCE+

This occurs when I try to run the following fuzzer in oss-fuzz locally:

#include "tinyxml2/tinyxml2.h"

extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
    // Create a new XMLDocument
    tinyxml2::XMLDocument doc;

    // Parse the input data
    if (doc.Parse((const char*)data, size) != tinyxml2::XML_SUCCESS) {
        return 0;
    }

    // Get the root element of the document
    tinyxml2::XMLElement* root = doc.RootElement();

    // Create a new XMLNode
    tinyxml2::XMLNode* newNode = doc.NewElement("newNode");

    // Insert the new node as the first child of the root element
    root->InsertFirstChild(newNode);

    return 0;
}