Qiling failed to emulate libc function call

[anaivebird]

*Describe the bug For strlen in libc, qiling failed to emulate it.

Emulated Code

size_t strlen(const char *s)
{
  return off_56561FBC(s);   // this line is 0x56555870
}

; Attributes: thunk

; size_t strlen(const char *s)
_strlen proc near

s= dword ptr  4

jmp     ds:off_56561FBC ; PIC mode    // this line is 0x56555870
_strlen endp

[=] Executing: 0x5655c1b2 [=] Executing: 0x5655c1b8 [=] Executing: 0x5655c1bb [=] Executing: 0x5655c1be [=] Executing: 0x56555870 // jmp ds:off_56561FBC [=] Executing: 0x876 [=] Executing: 0x878 [=] Executing: 0x87a [=] Executing: 0x87c

[xwings]

Anymore info ?

[anaivebird]

So the .so I analysis just called __strlen__ which he write himself which only contains jmp ds:off_56561FBC. So how qiling implement libc hooking(how qiling recognizes ds:off_56561FBC is libc.so:strlen?

Does my problem caused by I rebase the program on IDA pro and run qiling ida pro plugin to run my binary?

[wtdcode]

This is due to function hook implementation in qiling in order to implement set_api with proper interception. The memory at 0x876 is supposed to be mapped for function hooks. Does the program crash in your case?

[xwings]

Will you be able to try the latest version of Qiling and see if you still face same issue. There is lots of rework since 2021. Feel free to open a new issue if you have any similar problem.