xref: /freebsd/share/man/man9/vfs_suser.9 (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
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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 *mp" "struct thread *td"
40.Sh DESCRIPTION
41The
42.Fn vfs_suser
43function checks if the credentials given include superuser powers
44for the given mount point.
45It will check to see if the thread
46passed in has the same credentials as the user that mounted the
47file system.
48If so, it returns 0, otherwise it returns what
49.Xr priv_check 9
50would have returned.
51.Sh RETURN VALUES
52The
53.Fn vfs_suser
54function returns 0 if the user has superuser powers and
55.Er EPERM
56otherwise.
57This is the
58.Em reverse logic
59of some other implementations of
60.Fn suser
61in which a TRUE response indicates superuser powers.
62.Sh SEE ALSO
63.Xr chroot 2 ,
64.Xr jail 2
65.Sh HISTORY
66The
67.Fn vfs_suser
68function was introduced in
69.Fx 5.2 .
70.Sh AUTHORS
71This manual page was written by
72.An Alfred Perlstein .
73