bpf_get_file_xattr(9)

📦 version 7.3.1, in nixpkgs unstable

💅 bpf_get_file_xattr

okay bestie, welcome to the bpf_get_file_xattr(9) page — it lives in the Kernel API Manual and it's literally the vibe check for pulling extended attributes off a file from inside BPF land ✨

🎀 NAME

bpf_get_file_xattr — get xattr of a file 🗂️

✨ SYNOPSIS

__bpf_kfunc int bpf_get_file_xattr (struct file *file , const char
   *name__str , struct bpf_dynptr *value_p );

like, copy it exactly, no cap, this is the real signature 🫶

🌸 ARGUMENTS

  • file — the file you wanna get the xattr from 🗃️
  • name__str — the name of the xattr, iykyk 🏷️
  • value_p — the output buffer where the xattr value lands 📥

🦋 DESCRIPTION

So basically: get the xattr name__str of file and store the output in value_ptr. that's the whole plot 💅

⚠️ for security reasons, only name__str with the prefixes "user." or "security.bpf." are allowed. any other prefix? not today bestie, it's giving blocked 🙈

🔥 RETURN

on success you get the length of the xattr value 👑 on error you get a negative value 💀 (yes, negative, that's your red flag that something went sideways)

🌈 SEE ALSO

kernel file ./fs/bpf_fs_kfuncs.c — plus the whole friend group:

anyway that's the page, go read the source file ./fs, it's from October 2026 and this was bpf_get_file_xattr(9) — mwah, stay slay, drink water, and don't forget your xattr prefixes 💖🎀🫶

📦 where this page comes from