| Issue |
56489
|
| Summary |
LLDB crashes when loading core file due to divide-by-zero in ObjectFileELF::ParseSymbolTable()
|
| Labels |
lldb
|
| Assignees |
|
| Reporter |
Enna1
|
@Cossack9989 found a crash when fuzzing lldb.
This crash is cause by SIGFPE. a divide-by-zero bug occured if `symtab_hdr->sh_entsize` equals 0
https://github.com/llvm/llvm-project/blob/main/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp#L2350
A simple workaround approach is to add a non-zero check like this:
```patch
if (ReadSectionData(symtab, symtab_data) &&
ReadSectionData(strtab, strtab_data)) {
+ if (symtab_hdr->sh_entsize == 0)
+ return 0;
size_t num_symbols = symtab_data.GetByteSize() / symtab_hdr->sh_entsize;
return ParseSymbols(symbol_table, start_id, section_list, num_symbols,
symtab_data, strtab_data);
}
```
I'm not sure if this is the correct approach to fix this.
This can be reproduced with the attached bundle, [lldb-sigfpe.zip](https://github.com/llvm/llvm-project/files/9091047/lldb-sigfpe.zip), with ELF file and core file.
```
$ lldb -c corefile test
```
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