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elf.entry_point() for no-aslr binary #3745

@Eknight-Eutopia

Description

@Eknight-Eutopia

Problem

I'm new to LibAFL and I'm trying to work on a no-aslr binary, it's elf header type is EXEC, not DYN. And here is part of my code

   fn get_elf_entry_point(qemu: Qemu) -> Result<GuestAddr, Error> {
        let mut elf_buffer = Vec::new();
        let elf = EasyElf::from_file(qemu.binary_path(), &mut elf_buffer)?;
        let load_addr = qemu.load_addr();
        eprintln!("[Harness] ELF Load addr: {load_addr:#x}");
        let start_pc = elf
            .entry_point(qemu.load_addr())
            .expect("Target elf's entry_point should not be None!") as u64;

        // 使用 println! 确保能看到输出
        eprintln!("[Harness] ELF Entry point calculated: {start_pc:#x}");
        Ok(start_pc)

The problem is qemu.load_addr() will return 0x400000 and elf.entry_point(qemu.load_addr()) will return 0x802500(expected to be 0x402500).

The definition of elf.entry_point() is

    #[must_use]
    pub fn entry_point(&self, load_addr: GuestAddr) -> Option<GuestAddr> {
        if self.elf.entry == 0 {
            None
        } else {
            Some(load_addr + self.elf.entry as GuestAddr)
        }
    }

I wonder if this func need to add if self.if_pic() check liker other functions (eg. elf.resolve_symbol, elf.get_section) or just I misuse this function.

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