xref: /freebsd/share/man/man9/vfs_suser.9 (revision cbb3ec25236ba72f91cbdf23f8b78b9d1af0cedf)
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26.Dd April 2, 2004
27.Dt VFS_SUSER 9
28.Os
29.Sh NAME
30.Nm vfs_suser
31.Nd check if credentials have superuser privileges for a mount point
32.Sh SYNOPSIS
33.In sys/param.h
34.In sys/systm.h
35.In sys/mount.h
36.Ft int
37.Fn vfs_suser "struct mount *mp" "struct thread *td"
38.Sh DESCRIPTION
39The
40.Fn vfs_suser
41function checks if the credentials given include superuser powers
42for the given mount point.
43It will check to see if the thread
44passed in has the same credentials as the user that mounted the
45file system.
46If so, it returns 0, otherwise it returns what
47.Xr priv_check 9
48would have returned.
49.Sh RETURN VALUES
50The
51.Fn vfs_suser
52function returns 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.Sh HISTORY
64The
65.Fn vfs_suser
66function was introduced in
67.Fx 5.2 .
68.Sh AUTHORS
69This manual page was written by
70.An Alfred Perlstein .
71