xref: /freebsd/share/man/man9/vfs_suser.9 (revision 6b3455a7665208c366849f0b2b3bc916fb97516e)
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26.\" $FreeBSD$
27.\"
28.Dd April 2, 2004
29.Dt VFS_SUSER 9
30.Os
31.Sh NAME
32.Nm vfs_suser
33.Nd check if credentials have superuser privileges for a mount point
34.Sh SYNOPSIS
35.In sys/param.h
36.In sys/systm.h
37.In sys/mount.h
38.Ft int
39.Fn vfs_suser "struct mount *" "struct thread *td"
40.Sh DESCRIPTION
41The
42.Fn vfs_suser
43functions check if the credentials given include superuser powers
44for the given mountpoint.  It will check to see if the thread
45passed in has the same credentials as the user that mounted the
46filesystem, if so it returns 0, otherwise it returns what
47.Xr suser 9
48would have returned.
49.Sh RETURN VALUES
50The
51.Fn vfs_suser
52functions return 0 if the user has superuser powers and
53.Er EPERM
54otherwise.
55This is the
56.Em reverse logic
57of some other implementations of
58.Fn suser
59in which a TRUE response indicates superuser powers.
60.Sh SEE ALSO
61.Xr chroot 2 ,
62.Xr jail 2 ,
63.Xr suser 9
64.Sh HISTORY
65The
66.Fn vfs_suser
67function was introduced in
68.Fx 5.2 .
69.Sh AUTHORS
70This manual page was written by
71.An Alfred Perlstein .
72