heap use after free error in fuzz running
The fault was look like: `==11449==ERROR: AddressSanitizer: heap-use-after-free on address 0x604000fef5e8 at pc 0x7faed8ef861f bp 0x7fff313a18f0 sp 0x7fff313a18e8 READ of size 8 at 0x604000fef5e8 thread T0
#0 0x7faed8ef861e in xmlNodeDumpOutputInternal /opt/libxml2/xmlsave.c:897:48
#1 0x7faed8eea6ce in xmlDocContentDumpOutput /opt/libxml2/xmlsave.c:1228:7
#2 0x7faed8f0923d in xmlDocDumpFormatMemoryEnc__internal_alias /opt/libxml2/xmlsave.c:2392:5
#3 0x7faed8f09ffb in xmlDocDumpMemory__internal_alias /opt/libxml2/xmlsave.c:2424:5
#4 0x56a557 in LLVMFuzzerTestOneInput /opt/libxml2/fuzz/xml.c:53:5
#5 0x438b79 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) (/opt/libxml2/fuzz/.libs/lt-xml+0x438b79)
#6 0x439aed in fuzzer::Fuzzer::RunOne(unsigned char const*, unsigned long, bool, fuzzer::InputInfo*, bool*) (/opt/libxml2/fuzz/.libs/lt-xml+0x439aed)
#7 0x43b2a8 in fuzzer::Fuzzer::MutateAndTestOne() (/opt/libxml2/fuzz/.libs/lt-xml+0x43b2a8)
#8 0x43e2df in fuzzer::Fuzzer::Loop(std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, fuzzer::fuzzer_allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > const&) (/opt/libxml2/fuzz/.libs/lt-xml+0x43e2df)
#9 0x42ceef in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) (/opt/libxml2/fuzz/.libs/lt-xml+0x42ceef)
#10 0x421b72 in main (/opt/libxml2/fuzz/.libs/lt-xml+0x421b72)
#11 0x7faed7491432 in __libc_start_main (/lib64/libc.so.6+0x24432)
#12 0x421bad in _start (/opt/libxml2/fuzz/.libs/lt-xml+0x421bad)`
The crash file was uploaded: