upstream commit
fatal() when a remote window update causes the window
value to overflow. Reported by Georg Wicherski, ok markus@
Upstream-ID: ead397a9aceb3bf74ebfa5fcaf259d72e569f351
diff --git a/channels.c b/channels.c
index 8069cf1..3fe836a 100644
--- a/channels.c
+++ b/channels.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: channels.c,v 1.345 2015/06/30 05:23:25 djm Exp $ */
+/* $OpenBSD: channels.c,v 1.346 2015/06/30 05:25:07 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -2641,7 +2641,7 @@
{
Channel *c;
int id;
- u_int adjust;
+ u_int adjust, tmp;
if (!compat20)
return 0;
@@ -2657,7 +2657,10 @@
adjust = packet_get_int();
packet_check_eom();
debug2("channel %d: rcvd adjust %u", id, adjust);
- c->remote_window += adjust;
+ if ((tmp = c->remote_window + adjust) < c->remote_window)
+ fatal("channel %d: adjust %u overflows remote window %u",
+ id, adjust, c->remote_window);
+ c->remote_window = tmp;
return 0;
}