VFS_SUSER(9)

💖 VFS_SUSER 💖

okay so bestie, welcome to vfs_suser(9) — the Kernel Developer's Manual page for checking if somebody's credentials have superuser privileges for a mount point ✨ this is kernel dev territory, so grab your iced coffee and let's go 🫶

🌸 NAME 🌸

vfs_suser — check if credentials have superuser privileges for a mount point 👑

✨ SYNOPSIS ✨

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mount.h>

int
vfs_suser(struct mount *mp, struct thread *td);

literally just three includes and one function, we love a minimal entrance 💅

🎀 DESCRIPTION 🎀

so the vfs_suser() function checks if the credentials you handed it include superuser powers for the given mount point. it's giving "are you the moment or not" 🦋

here's the vibe check it runs: it looks at whether the thread you passed in has the same credentials as the user that mounted the file system. if yes — it returns 0 🎉 otherwise it returns what priv_check(9) would have returned. no cap, that's the whole thing.

🔥 RETURN VALUES 🔥

• the vfs_suser() function returns 0 if the user has superuser powers 💅
• and EPERM otherwise 💀

bestie, pay attention here — this is the reverse logic of some other implementations of suser() in which a TRUE response indicates superuser powers. so don't come in here thinking nonzero = yes. it's not that. 🙈

🌈 SEE ALSO 🌈

• chroot(2)
• jail(2)

⭐ HISTORY ⭐

the vfs_suser() function was introduced in FreeBSD 5.2. iconic era honestly 👑

💜 AUTHORS 💜

this manual page was written by Alfred Perlstein. thank u king 🫶

okay and that's a wrap, bestie 🎀 this little gem came out of the Debian corner of the world, dated April 2, 2004, and it lives under the VFS_SUSER(9) name. go forth and check those credentials ✨💖