elf_read_from_buffer(9)

📦 version 7.3.1, in nixpkgs unstable

💅 elf_read_from_buffer(9) — like, the whole vibe

okay so bestie, welcome to the Kernel API Manual ✨ this one's called elf_read_from_buffer, and it's a level-9 kernel function (9 in the name, iykyk — that's the section). Sit down, grab a boba, and let's get into it 🧋

🌸 NAME 🌸

elf_read_from_buffer — reads an ELF file and sets up the ELF header and the ELF info. Like, both. At once. She does it all 💅

✨ SYNOPSIS ✨

int elf_read_from_buffer (const char *buf , size_t len , struct elfhdr
*ehdr , struct kexec_elf_info *elf_info );

yeah she takes four things and returns an int, no cap 🫶

🎀 ARGUMENTS 🎀

  • buf — the buffer you're reading the ELF file from. that's the whole source of truth, bestie 📥
  • len — the size of buf. how many bytes we're working with, fr fr 📏
  • ehdr — a pointer to an existing struct, and this is the one that gets populated. it already exists, we're just filling her in 💖
  • elf_info — another pointer to an existing struct, also getting populated. same deal, gorgeous 🌸

🦋 DESCRIPTION 🦋

So here's the main character energy: this function lets you read ELF files that have a different byte order than the kernel. Different. Not matching. And she handles it, because she byte-swaps the fields as needed 🔥

that's the flex. that's literally the whole flex. cross-endian ELF reading and she's not even sweating 😭

⭐ RETURN ⭐

On success it returns 0 — icon, ate, no crumbs 👑

⚠️ and this part is important bestie: after it returns 0, the caller should call kexec_free_elf_info(elf_info) to free the memory that got allocated for the section and program headers. do not forget. do not ghost her. free your memory 🙈

🌈 SEE ALSO 🌈

Kernel file ./kernel/kexec_elf.c — plus all her friends:

and that's the page, bestie 🎀 this whole thing lives in ./kernel, dated October 2026 — so if you need to cite her, that's where she's from. slay, go read some ELF files 💜🦋

📦 where this page comes from