Document kcopy() and add a note that copystr() does not return EFAULT

when it encounters an illegal address.

Discussed with deraadt, guenther, and kettenis.

1 files changed, 23 insertions, 2 deletions

diff --git a/share/man/man9/copy.9 b/share/man/man9/copy.9
index f720443ff31..c62e675aa68 100644
--- a/share/man/man9/copy.9
+++ b/share/man/man9/copy.9
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: copy.9,v 1.14 2007/05/31 19:20:00 jmc Exp $
+.\"	$OpenBSD: copy.9,v 1.15 2012/06/21 18:01:40 matthew Exp $
 .\"	$NetBSD: copy.9,v 1.2 1996/01/09 03:23:04 thorpej Exp $
 .\"
 .\" Copyright (c) 1996 Jason R. Thorpe.
@@ -33,7 +33,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: May 31 2007 $
+.Dd $Mdocdate: June 21 2012 $
 .Dt COPY 9
 .Os
 .Sh NAME
@@ -52,12 +52,16 @@
 .Fn copyinstr "const void *uaddr" "void *kaddr" "size_t len" "size_t *done"
 .Ft int
 .Fn copyoutstr "const void *kaddr" "void *uaddr" "size_t len" "size_t *done"
+.Ft int
+.Fn kcopy "const void *kfaddr" "void *kdaddr" "size_t len"
 .Sh DESCRIPTION
 The
 .Nm
 functions are designed to copy contiguous data from one address to another.
 All but
 .Fn copystr
+and
+.Fn kcopy
 copy data from user-space to kernel-space or vice-versa.
 .Pp
 The
@@ -92,6 +96,16 @@ if
 .Fa done
 is not
 .Dv NULL .
+.Pp
+Unlike the other
+.Nm
+functions,
+.Fn copystr
+does
+.Em not
+support returning
+.Er EFAULT
+when a bad address is encountered.
 .It Fn copyinstr
 Copies a null-terminated string, at most
 .Fa len
@@ -120,6 +134,13 @@ if
 .Fa done
 is not
 .Dv NULL .
+.It Fn kcopy
+Copies
+.Fa len
+bytes of data from the kernel-space address
+.Fa kfaddr
+to the kernel-space address
+.Fa kdaddr .
 .El
 .Sh RETURN VALUES
 The