ipc_check_perms(9)

📦 version 7.3.1, in nixpkgs unstable

💅 ipc_check_perms — check security and permissions for an ipc object

okay so bestie, this is a page from the Kernel API Manual (yes, the kernel has lore too) and it's literally about double-checking that you're allowed to touch an ipc object. security girl summer 🎀

✨ SYNOPSIS ✨

int ipc_check_perms (struct ipc_namespace *ns , struct kern_ipc_perm
*ipcp , const struct ipc_ops *ops , struct ipc_params *params );

like, that's the whole vibe. one function, four args, returns an int. slay.

🫶 ARGUMENTS 🫶

  • ns — the ipc namespace, bestie. it's giving "which world are we in".
  • ipcp — the ipc permission set. this is the whole receipts folder for who's allowed what 👑
  • ops — the actual security routine to call. like, the real one doing the work, we're just the messenger 💅
  • params — its parameters. you know, the little bag of stuff ops needs. 🎀

🌸 DESCRIPTION 🌸

so here's the tea: this routine gets called by sys_msgget, sys_semget and sys_shmget — but only when the key is not IPC_PRIVATE and that key already exists in the ds IDR. like it's the "oh you think you know this object already? prove it" checkpoint 🔥

On success, the ipc id is returned. periodt. that's the win condition ✨

and just so we're clear: it is called with ipc_ids.rwsem and ipcp->lock held. do not show up without your locks, that's not the vibe 😭

🦋 SEE ALSO 🦋

Kernel file ./ipc/util.c — and honestly the whole friend group:

okay that's the whole page!! mwah 💖 this one lives in ./ipc and it's dated October 2026, so like… future icon behavior tbh 🌈⭐ go check your permissions bestie, iykyk 💜

📦 where this page comes from