fscrypt_prepare_symlink(9)

📦 version 7.3.1, in nixpkgs unstable

okay so bestie, welcome to the Kernel API Manual page for fscrypt_prepare_symlink(9) — yes that's the whole name, no she did not come to play with shortening it. this is your girl's guide to getting a possibly-encrypted symlink ready to exist in the world 🎀

✨ NAME ✨

fscrypt_prepare_symlink — get everything prepped to create a symlink that might be encrypted, no cap 🦋

✨ SYNOPSIS ✨

int fscrypt_prepare_symlink (struct inode *dir , const char *target ,
unsigned int len , unsigned int max_len , struct fscrypt_str *disk_link
);

✨ ARGUMENTS ✨

  • dir — the directory where this symlink is about to be born. her home. her whole vibe. 🏠
  • target — the plaintext symlink target, i.e. the thing the symlink actually points at, before any encryption glow-up ✨
  • len — how long target is, not counting the null terminator. like, do not include it, that's not part of the length bestie 🙈
  • max_len — the amount of space the filesystem actually has available to store the symlink target. think of it as the closet space and the target better fit 💀
  • disk_link — (out) the on-disk symlink target that's being prepared. this is where the results get written, so she's an output param, treat her right 💖

✨ DESCRIPTION ✨

so what does this function actually do? glad you asked 🫶

It computes the size the symlink target will need on-disk, stores that size in disk_link->len, and validates it against max_len. and like — important detail — an encrypted symlink may end up longer than the original. yes really. encryption adds length, that's just how it is, don't shoot the messenger 😭

On top of that, disk_link->name gets set to target if the symlink is gonna be unencrypted. but it's left NULL if the symlink is gonna be encrypted. so if you see a NULL there, that's not a bug, that's the vibe check result 🔥

For encrypted symlinks, the filesystem has to call fscrypt_encrypt_symlink later to actually create the on-disk target. and before you ask why it's a whole two-step situation — the reason is that some filesystems genuinely need to know the size of the symlink target before creating the inode. like, for example, to figure out whether it's gonna be a "fast" or "slow" symlink. so the two-step process is doing real work, she's not just being extra 💅

✨ RETURN ✨

  • 0 on success — slay, we ate 👑
  • -ENAMETOOLONG if the symlink target is too long — the closet was too small, tragic 🌸
  • -ENOKEY if the encryption key is missing — where is she. where did she go. 🔍
  • any other -errno code if something went wrong while setting up the encryption key — a general "it's giving complications" situation 💀

✨ SEE ALSO ✨

go read those too, iykyk 🌈

fr fr though — if disk_link->name comes back NULL, do not panic and do not skip the fscrypt_encrypt_symlink step. that's the encrypted path and she needs her second step or nothing works. periodt 💜

k that's the whole page, mwah 🍓 — this one lives under ./fs/crypto, dated October 2026, and it's part of the Kernel API Manual. go forth and make symlinks, bestie, and remember: encrypt responsibly ✨🧚💖

📦 where this page comes from