qiling framework has a potential issue when handling `env` parameters of type bytes.

[noobone123]

Hello, the bug I found is very similar to issue #635. I guess that the developers have overlooked this issue again after refactoring the relevant code.

Describe the bug
In qiling/loader/elf.py, line 297, has following code

# write env
for k, v in env.items():
    new_stack = __push_str(new_stack, f'{k}={v}')
    elf_table.extend(self.ql.pack(new_stack))

while __push_str is in line 275

def __push_str(top: int, s: str) -> int:
    """Write a string to stack memory and adjust the top of stack accordingly.
    Top of stack remains aligned to pointer size
    """

    data = s.encode('latin') + b'\x00'
    top = self.ql.mem.align(top - len(data), self.ql.arch.pointersize)
    self.ql.mem.write(top, data)

    return top

If k and v in env is of type bytes, f'{k}={v}' will force convert the bytes k into str, which would cause bugs.
Additionally, there is only a __push_str function which can not handle case when the argv or env is of type bytes.

Sample Code
the env with bytes data is passed into Qiling like following:

ql = Qiling(["x8664_freebsd/bin/x8664_hello_asm"], "x8664_freebsd", env = {b"key": b"\xff"})
ql.run()

Screenshots

Additional context
As you can see, bytes is converted into str and has new char b, ' added into it, this is not we want.

It's worth noting that this bug doesn't cause the Python program to throw any exceptions, but the bug exactly exists.

I have create a PR #1380 to fix this bug (maybe a little dirty).