etelf mirror elf generation (1-1 output) failed to update function address in _start

[orcguru]

Unfortunately I had some binaries which setup _libc_start_main parameter by mov instructions on x86_64. In below example 0x531e30 points to __libc_csu_init, however etelf failed to update 0x531e30 to the new address, and so crash happens...

0000000040000018 <_start>:
40000018: 31 ed xor %ebp,%ebp
4000001a: 49 89 d1 mov %rdx,%r9
4000001d: 5e pop %rsi
4000001e: 48 89 e2 mov %rsp,%rdx
40000021: 48 83 e4 f0 and $0xfffffffffffffff0,%rsp
40000025: 50 push %rax
40000026: 54 push %rsp
40000027: 49 c7 c0 20 1e 53 00 mov $0x531e20,%r8
4000002e: 48 c7 c1 30 1e 53 00 mov $0x531e30,%rcx
40000035: 48 c7 c7 70 39 42 00 mov $0x423970,%rdi
4000003c: e8 8f 02 60 c0 callq 6002d0 __libc_start_main@plt
40000041: f4 hlt
40000042: 90 nop
40000043: 90 nop

Maybe I will try to manually update it for now, and see if I have time to dig into this later...

[orcguru]

Unfortunately my CentOS creates elf that has constant addresses all over the places... I will give it a try to work around the problem, and will definitely publish the patch if I have one...