From owner-svn-src-all@FreeBSD.ORG Sun Jan 25 19:45:45 2015 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 497D0605; Sun, 25 Jan 2015 19:45:45 +0000 (UTC) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 1B61BE9E; Sun, 25 Jan 2015 19:45:45 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.9/8.14.9) with ESMTP id t0PJjieQ046432; Sun, 25 Jan 2015 19:45:44 GMT (envelope-from jhb@FreeBSD.org) Received: (from jhb@localhost) by svn.freebsd.org (8.14.9/8.14.9/Submit) id t0PJjikt046431; Sun, 25 Jan 2015 19:45:44 GMT (envelope-from jhb@FreeBSD.org) Message-Id: <201501251945.t0PJjikt046431@svn.freebsd.org> X-Authentication-Warning: svn.freebsd.org: jhb set sender to jhb@FreeBSD.org using -f From: John Baldwin Date: Sun, 25 Jan 2015 19:45:44 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r277709 - head/sys/netinet X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 25 Jan 2015 19:45:45 -0000 Author: jhb Date: Sun Jan 25 19:45:44 2015 New Revision: 277709 URL: https://svnweb.freebsd.org/changeset/base/277709 Log: Use an sbuf to generate the output of the net.inet.tcp.hostcache.list sysctl to avoid a possible buffer overflow if the cache grows while the text is being generated. PR: 172675 MFC after: 2 weeks Modified: head/sys/netinet/tcp_hostcache.c Modified: head/sys/netinet/tcp_hostcache.c ============================================================================== --- head/sys/netinet/tcp_hostcache.c Sun Jan 25 19:21:37 2015 (r277708) +++ head/sys/netinet/tcp_hostcache.c Sun Jan 25 19:45:44 2015 (r277709) @@ -73,6 +73,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include #include #include @@ -595,30 +596,27 @@ tcp_hc_update(struct in_conninfo *inc, s static int sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS) { - int bufsize; int linesize = 128; - char *p, *buf; - int len, i, error; + struct sbuf sb; + int i, error; struct hc_metrics *hc_entry; #ifdef INET6 char ip6buf[INET6_ADDRSTRLEN]; #endif - bufsize = linesize * (V_tcp_hostcache.cache_count + 1); + sbuf_new(&sb, NULL, linesize * (V_tcp_hostcache.cache_count + 1), + SBUF_FIXEDLEN); - p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO); - - len = snprintf(p, linesize, - "\nIP address MTU SSTRESH RTT RTTVAR BANDWIDTH " + sbuf_printf(&sb, + "\nIP address MTU SSTRESH RTT RTTVAR BANDWIDTH " " CWND SENDPIPE RECVPIPE HITS UPD EXP\n"); - p += len; #define msec(u) (((u) + 500) / 1000) for (i = 0; i < V_tcp_hostcache.hashsize; i++) { THC_LOCK(&V_tcp_hostcache.hashbase[i].hch_mtx); TAILQ_FOREACH(hc_entry, &V_tcp_hostcache.hashbase[i].hch_bucket, rmx_q) { - len = snprintf(p, linesize, + sbuf_printf(&sb, "%-15s %5lu %8lu %6lums %6lums %9lu %8lu %8lu %8lu " "%4lu %4lu %4i\n", hc_entry->ip4.s_addr ? inet_ntoa(hc_entry->ip4) : @@ -640,13 +638,13 @@ sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS) hc_entry->rmx_hits, hc_entry->rmx_updates, hc_entry->rmx_expire); - p += len; } THC_UNLOCK(&V_tcp_hostcache.hashbase[i].hch_mtx); } #undef msec - error = SYSCTL_OUT(req, buf, p - buf); - free(buf, M_TEMP); + sbuf_finish(&sb); + error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); + sbuf_delete(&sb); return(error); }