Capstone Next Bug in code. modRMRequired has an invalid index read

[trile127]

Work environment

Questions	Answers
OS/arch/bits	Ubuntu 22.04 64 Bit
Architecture	x86
Source of Capstone	git clone
Version/git commit	next, fe60b1371c109288278faa06b7efb545b18ed45d

Expected behavior

no error, or segfault

Actual behavior

Using Valgrind for information ==312219== Invalid read of size 1 ==312219== at 0x120CFC: modRMRequired (X86DisassemblerDecoder.c:139) ==312219== by 0x120CFC: getIDWithAttrMask (X86DisassemblerDecoder.c:910) ==312219== by 0x121946: getID (X86DisassemblerDecoder.c:1221) ==312219== by 0x121946: decodeInstruction (X86DisassemblerDecoder.c:2337) ==312219== by 0x1192E7: X86_getInstruction (X86Disassembler.c:982) ==312219== by 0x117950: cs_disasm_iter (cs.c:1408) ==312219== by 0x110DF5: disassemble_symbol_funcs (main.c:711) ==312219== by 0x1122AF: main (main.c:1126) ==312219== Address 0x19 is not stack'd, malloc'd or (recently) free'd

Ends with a segfault

Steps to reproduce the behavior

Run cs_disasm on /usr/bin/Xephyr ".text" section and it will crash after awhile

• Use code markdown CODE to make your code visible

I take the .text section and just read it in byte by byte, it will error out over time. I've tried cs_disasm_iter and cs_disasm reading in chunks of 4096 at a time.

cs_insn *insn = cs_malloc(handle);
             fflush(stdout);
                while(cs_disasm_iter(handle, &chunk_ptr, &bytesRead, &(sym->st_value), insn)) {

                    offset += insn->size;
                    printf("0x%" PRIx64 ": %s %s, insns bytes: ", insn->address, insn->mnemonic, insn->op_str);

                    for (int i = 0; i < insn->size; i++) {
                        printf("%02x ", insn->bytes[i]);
                    }

                    printf("\n");

                }

Also, this errors for v5 as well