Author: jhb
Date: Thu Jun 18 21:24:23 2009
New Revision: 194463
URL: http://svn.freebsd.org/changeset/base/194463
Log:
MFC: Fix overflow edge cases with comparing ticks to t_rcvtime including
fixing the TCP keepalive timer to work properly when ticks overflows from
INT_MAX to INT_MIN. Note that to preserve the ABI this change just
downcasts t_rcvtime to an int when it is subtracted from ticks rather than
changing the type of t_rcvtime.
Modified:
stable/6/sys/netinet/tcp_output.c
stable/6/sys/netinet/tcp_timer.c
Modified: stable/6/sys/netinet/tcp_output.c
==============================================================================
--- stable/6/sys/netinet/tcp_output.c Thu Jun 18 21:17:04 2009
(r194462)
+++ stable/6/sys/netinet/tcp_output.c Thu Jun 18 21:24:23 2009
(r194463)
@@ -145,7 +145,7 @@ tcp_output(struct tcpcb *tp)
* to send, then transmit; otherwise, investigate further.
*/
idle = (tp->t_flags & TF_LASTIDLE) || (tp->snd_max == tp->snd_una);
- if (idle && (ticks - tp->t_rcvtime) >= tp->t_rxtcur) {
+ if (idle && (ticks - (int)tp->t_rcvtime) >= tp->t_rxtcur) {
/*
* We have been idle for "a while" and no acks are
* expected to clock out any data we send --
Modified: stable/6/sys/netinet/tcp_timer.c
==============================================================================
--- stable/6/sys/netinet/tcp_timer.c Thu Jun 18 21:17:04 2009
(r194462)
+++ stable/6/sys/netinet/tcp_timer.c Thu Jun 18 21:24:23 2009
(r194463)
@@ -188,7 +188,7 @@ tcp_timer_2msl(xtp)
* control block. Otherwise, check again in a bit.
*/
if (tp->t_state != TCPS_TIME_WAIT &&
- (ticks - tp->t_rcvtime) <= tcp_maxidle)
+ (ticks - (int)tp->t_rcvtime) <= tcp_maxidle)
callout_reset(tp->tt_2msl, tcp_keepintvl,
tcp_timer_2msl, tp);
else
@@ -291,7 +291,7 @@ tcp_timer_keep(xtp)
goto dropit;
if ((always_keepalive || inp->inp_socket->so_options & SO_KEEPALIVE) &&
tp->t_state <= TCPS_CLOSING) {
- if ((ticks - tp->t_rcvtime) >= tcp_keepidle + tcp_maxidle)
+ if ((ticks - (int)tp->t_rcvtime) >= tcp_keepidle + tcp_maxidle)
goto dropit;
/*
* Send a packet designed to force a response
@@ -377,8 +377,8 @@ tcp_timer_persist(xtp)
* backoff that we would use if retransmitting.
*/
if (tp->t_rxtshift == TCP_MAXRXTSHIFT &&
- ((ticks - tp->t_rcvtime) >= tcp_maxpersistidle ||
- (ticks - tp->t_rcvtime) >= TCP_REXMTVAL(tp) * tcp_totbackoff)) {
+ ((ticks - (int)tp->t_rcvtime) >= tcp_maxpersistidle ||
+ (ticks - (int)tp->t_rcvtime) >= TCP_REXMTVAL(tp) *
tcp_totbackoff)) {
tcpstat.tcps_persistdrop++;
tp = tcp_drop(tp, ETIMEDOUT);
goto out;
_______________________________________________
[email protected] mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "[email protected]"
