As always with these admirable hacks, I feel compelled to point out these are not really ELF executables but just small files you can trick the x86_64 Linux kernel into loading.
I mean they're very clever and legit and kudos to the people who develop these exploits, but they're not ELF.
301 bytes! The base64 one-liner install is a nice flex. Accepting an infinite loop when energy_full doesn't exist is peak code golf, perfectly reasonable when every byte counts. Is there a writeup on the assembly somewhere?
It doesn't even look like particularly optimised Asm (could immediately spot a few savings, despite how horrible GAS syntax is to read...), but is definitely not "compiler slop"[1] either, which shows just how inefficient the majority of programs actually are. Of course even the ELF header takes up a significant amount of space, but this reminds me of how PC magazines would print short listings of utilities like this, often a few dozen up to a few hundred bytes at most --- in DOS .COM format, which is headerless and thus pure machine instructions.
[1] In the late 80s and early 90s, the battle between those writing handwritten Asm and those using compiled HLLs has many similarities to AI-generated vs non-AI code today.
If the savings are about `mov $1, %edi` and `mov $10, %ecx`, those 32-bit immediate values line up with the higher bytes of p_filesz and p_memsz in the program header, which have to be zero [1]. If not, what are the savings? :)
As always with these admirable hacks, I feel compelled to point out these are not really ELF executables but just small files you can trick the x86_64 Linux kernel into loading.
I mean they're very clever and legit and kudos to the people who develop these exploits, but they're not ELF.
Love it! It's entirely inapplicable and useless to me but it embodies the spirit of Show HN and what the spirit of programming in the 80s and 90s was.
I have a use for this: A somewhat portable one-liner to go in my waybar/sway/i3 configs!
301 bytes! The base64 one-liner install is a nice flex. Accepting an infinite loop when energy_full doesn't exist is peak code golf, perfectly reasonable when every byte counts. Is there a writeup on the assembly somewhere?
The xz step doesn't seem to be doing very much, though. It seems the decoded data is currently 278 bytes versus a 298-byte decompressed result.
Haha this is great!
What about adding a Make rule to auto-generate the one-liner install from the binary?
It doesn't even look like particularly optimised Asm (could immediately spot a few savings, despite how horrible GAS syntax is to read...), but is definitely not "compiler slop"[1] either, which shows just how inefficient the majority of programs actually are. Of course even the ELF header takes up a significant amount of space, but this reminds me of how PC magazines would print short listings of utilities like this, often a few dozen up to a few hundred bytes at most --- in DOS .COM format, which is headerless and thus pure machine instructions.
[1] In the late 80s and early 90s, the battle between those writing handwritten Asm and those using compiled HLLs has many similarities to AI-generated vs non-AI code today.
If the savings are about `mov $1, %edi` and `mov $10, %ecx`, those 32-bit immediate values line up with the higher bytes of p_filesz and p_memsz in the program header, which have to be zero [1]. If not, what are the savings? :)
[1]: https://github.com/meribold/btry/commit/8ef5a4ce58ae73c489d2...
Love this kind of tiny, over‑engineered hack—totally impractical, but pure Show HN energy.