[src/trunk]: src/share/man/man4 Document that overflow in P[X+k:n] terminates...

[alnsn <alnsn%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/9fd1fd33c480
branches:  trunk
changeset: 772344:9fd1fd33c480
user:      alnsn <alnsn%NetBSD.org@localhost>
date:      Fri Dec 30 14:12:15 2011 +0000

description:
Document that overflow in P[X+k:n] terminates a filter program.
Based on a discussion with Christos on source-changes-d.

diffstat:

 share/man/man4/bpf.4 |  4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diffs (20 lines):

diff -r 78a981c2ad16 -r 9fd1fd33c480 share/man/man4/bpf.4
--- a/share/man/man4/bpf.4      Fri Dec 30 13:08:30 2011 +0000
+++ b/share/man/man4/bpf.4      Fri Dec 30 14:12:15 2011 +0000
@@ -1,6 +1,6 @@
 .\" -*- nroff -*-
 .\"
-.\"    $NetBSD: bpf.4,v 1.48 2011/12/27 21:47:04 wiz Exp $
+.\"    $NetBSD: bpf.4,v 1.49 2011/12/30 14:12:15 alnsn Exp $
 .\"
 .\" Copyright (c) 1990, 1991, 1992, 1993, 1994
 .\"    The Regents of the University of California.  All rights reserved.
@@ -515,6 +515,8 @@
 .Sy ( BPF_H ) ,
 or byte
 .Sy ( BPF_B ) .
+Arithmetic overflow when calculating a variable offset terminates
+the filter program and the packet is ignored.
 The semantics of all the recognized BPF_LD instructions follow.
 .Bl -column "BPF_LD_BPF_W_BPF_ABS" "A \*[Lt]- P[k:4]" -offset indent
 .It Sy BPF_LD+BPF_W+BPF_ABS Ta A \*[Lt]- P[k:4]