cap_task_fix_setuid(9)

📦 version 7.3.1, in nixpkgs unstable

💅 cap_task_fix_setuid(9)

okay so bestie, welcome to the Kernel API Manual, section 9 — pull up a chair, we're talking about cap_task_fix_setuid, and honestly? it's giving "tiny function, big responsibilities." 🎀

✨ NAME ✨

cap_task_fix_setuid — the little guy that fixes up the results of a setuid() call 🫶

🌸 SYNOPSIS 🌸

int cap_task_fix_setuid (struct cred *new , const struct cred *old , int flags );

like, that's the whole signature, and yes it returns an int, we'll get to that 💖

🦋 ARGUMENTS 🦋

  • new — the proposed credentials 👑 like, the outfit your task wants to wear
  • old — the current task's current credentials 🌈 the outfit it's wearing right now
  • flags — indications of what has changed 🕵️‍♀️ a lil heads-up about what's different

💜 DESCRIPTION 💜

so what does it do? it fixes up the results of the setuid call before the credential changes are actually applied ✨ like a bouncer checking your fit before you get into the club, no cap.

that's it. that's the vibe. it does the fix-up first, then the credential changes go through. periodt 💅

🔥 RETURN 🔥

  • 0 — grant the changes ✅ slay, you're in
  • -ve — deny them 💀 (negative value, i.e. the vibe check failed)

🌟 SEE ALSO 🌟

the whole friend group, fr fr — and the kernel file ./security/commoncap.c 🍓:

💡 reminder bestie: every single one of those is a real page, go read them, iykyk 📚

okay that's the whole thing, mwah 💋 — this page lives in ./security, dated October 2026, and it's brought to you by the Kernel API Manual gang. catch you in the next manpage, bestie 🧚‍♀️💖

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