svn commit: r358023 - head/sys/netinet

[Michael Tuexen]

Author: tuexen
Date: Mon Feb 17 14:54:21 2020
New Revision: 358023
URL: https://svnweb.freebsd.org/changeset/base/358023

Log:
  Don't use uninitialised stack memory if the sysctl variable
  net.inet.tcp.hostcache.enable is set to 0.
  The bug resulted in using possibly a too small MSS value or wrong
  initial retransmission timer settings. Possibly the value used
  for ssthresh was also wrong.
  
  Submitted by:		Richard Scheffenegger
  Reviewed by:		Cheng Cui, rgrimes@, tuexen@
  MFC after:		1 week
  Differential Revision:	https://reviews.freebsd.org/D23687

Modified:
  head/sys/netinet/tcp_hostcache.c

Modified: head/sys/netinet/tcp_hostcache.c
==============================================================================
--- head/sys/netinet/tcp_hostcache.c	Mon Feb 17 13:31:30 2020	(r358022)
+++ head/sys/netinet/tcp_hostcache.c	Mon Feb 17 14:54:21 2020	(r358023)
@@ -437,8 +437,10 @@ tcp_hc_get(struct in_conninfo *inc, struct hc_metrics_
 {
 	struct hc_metrics *hc_entry;
 
-	if (!V_tcp_use_hostcache)
+	if (!V_tcp_use_hostcache) {
+		bzero(hc_metrics_lite, sizeof(*hc_metrics_lite));
 		return;
+	}
 
 	/*
 	 * Find the right bucket.