Date: Wed, 6 Jan 2010 16:49:00 +0000 (UTC) From: "Bjoern A. Zeeb" <bz@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-7@freebsd.org Subject: svn commit: r201654 - stable/7/sys/netinet Message-ID: <201001061649.o06Gn0wd081668@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: bz Date: Wed Jan 6 16:48:59 2010 New Revision: 201654 URL: http://svn.freebsd.org/changeset/base/201654 Log: MFC r184720: Fix a bug introduced with r182851 (r201653 in stable/7) splitting tcp_mss() into tcp_mss() and tcp_mss_update() so that tcp_mtudisc() could re-use the same code. In case we return early and got a metricptr to pass the hostcache info back to the caller we need to initialize the data to a defined state (zero it) as tcp_hc_get() would do if there was no hit. Without that the caller would check on random stack garbage which could lead to undefined results. This only affected tcp_mss() if there was no routing entry for the peer, tcp_mtudisc() was not affected. Modified: stable/7/sys/netinet/tcp_input.c Directory Properties: stable/7/sys/ (props changed) stable/7/sys/cddl/contrib/opensolaris/ (props changed) stable/7/sys/contrib/dev/acpica/ (props changed) stable/7/sys/contrib/pf/ (props changed) Modified: stable/7/sys/netinet/tcp_input.c ============================================================================== --- stable/7/sys/netinet/tcp_input.c Wed Jan 6 16:43:09 2010 (r201653) +++ stable/7/sys/netinet/tcp_input.c Wed Jan 6 16:48:59 2010 (r201654) @@ -2761,8 +2761,16 @@ tcp_mss_update(struct tcpcb *tp, int off /* * No route to sender, stay with default mss and return. */ - if (maxmtu == 0) + if (maxmtu == 0) { + /* + * In case we return early we need to intialize metrics + * to a defined state as tcp_hc_get() would do for us + * if there was no cache hit. + */ + if (metricptr != NULL) + bzero(metricptr, sizeof(struct hc_metrics_lite)); return; + } /* Check the interface for TSO capabilities. */ if (mtuflags & CSUM_TSO)
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201001061649.o06Gn0wd081668>