Fix resource exhaustion in TCP reassembly. [SA-15:15]

Fix OpenSSH multiple vulnerabilities. [SA-15:16]

Fix BIND remote denial of service vulnerability. [SA-15:17]

Approved by:	so

8 files changed, 72 insertions, 61 deletions

diff --git a/UPDATING b/UPDATING
index 124467c39f00..c5a3881171b7 100644
--- a/UPDATING
+++ b/UPDATING
@@ -11,6 +11,16 @@ handbook:
 Items affecting the ports and packages system can be found in
 /usr/ports/UPDATING.  Please read that file before running portupgrade.
 
+20150728:	p21	FreeBSD-SA-15:15.tcp
+			FreeBSD-SA-15:16.openssh
+			FreeBSD-SA-15:17.bind
+
+	Fix resource exhaustion in TCP reassembly. [SA-15:15]
+
+	Fix OpenSSH multiple vulnerabilities. [SA-15:16]
+
+	Fix BIND remote denial of service vulnerability. [SA-15:17]
+
 20150721:	p20	FreeBSD-SA-15:13.tcp
 
 	Fix resource exhaustion due to sessions stuck in LAST_ACK state.
diff --git a/contrib/bind9/lib/dns/tkey.c b/contrib/bind9/lib/dns/tkey.c
index 11b4f49eb04b..ada26bc08b58 100644
--- a/contrib/bind9/lib/dns/tkey.c
+++ b/contrib/bind9/lib/dns/tkey.c
@@ -650,6 +650,7 @@ dns_tkey_processquery(dns_message_t *msg, dns_tkeyctx_t *tctx,
 		 * Try the answer section, since that's where Win2000
 		 * puts it.
 		 */
+		name = NULL;
 		if (dns_message_findname(msg, DNS_SECTION_ANSWER, qname,
 					 dns_rdatatype_tkey, 0, &name,
 					 &tkeyset) != ISC_R_SUCCESS) {
diff --git a/crypto/openssh/auth2-chall.c b/crypto/openssh/auth2-chall.c
index 980250a91c3e..791be5ca3c9f 100644
--- a/crypto/openssh/auth2-chall.c
+++ b/crypto/openssh/auth2-chall.c
@@ -82,6 +82,7 @@ struct KbdintAuthctxt
 	void *ctxt;
 	KbdintDevice *device;
 	u_int nreq;
+	u_int devices_done;
 };
 
 #ifdef USE_PAM
@@ -168,11 +169,15 @@ kbdint_next_device(Authctxt *authctxt, KbdintAuthctxt *kbdintctxt)
 		if (len == 0)
 			break;
 		for (i = 0; devices[i]; i++) {
-			if (!auth2_method_allowed(authctxt,
+			if ((kbdintctxt->devices_done & (1 << i)) != 0 ||
+			    !auth2_method_allowed(authctxt,
 			    "keyboard-interactive", devices[i]->name))
 				continue;
-			if (strncmp(kbdintctxt->devices, devices[i]->name, len) == 0)
+			if (strncmp(kbdintctxt->devices, devices[i]->name,
+			    len) == 0) {
 				kbdintctxt->device = devices[i];
+				kbdintctxt->devices_done |= 1 << i;
+			}
 		}
 		t = kbdintctxt->devices;
 		kbdintctxt->devices = t[len] ? xstrdup(t+len+1) : NULL;
diff --git a/crypto/openssh/sshconnect.c b/crypto/openssh/sshconnect.c
index fd8ad1dd3348..25ced5735dc6 100644
--- a/crypto/openssh/sshconnect.c
+++ b/crypto/openssh/sshconnect.c
@@ -1247,29 +1247,39 @@ verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 {
 	int flags = 0;
 	char *fp;
+	Key *plain = NULL;
 
 	fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
 	debug("Server host key: %s %s", key_type(host_key), fp);
 	free(fp);
 
-	/* XXX certs are not yet supported for DNS */
-	if (!key_is_cert(host_key) && options.verify_host_key_dns &&
-	    verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) {
-		if (flags & DNS_VERIFY_FOUND) {
-
-			if (options.verify_host_key_dns == 1 &&
-			    flags & DNS_VERIFY_MATCH &&
-			    flags & DNS_VERIFY_SECURE)
-				return 0;
-
-			if (flags & DNS_VERIFY_MATCH) {
-				matching_host_key_dns = 1;
-			} else {
-				warn_changed_key(host_key);
-				error("Update the SSHFP RR in DNS with the new "
-				    "host key to get rid of this message.");
+	if (options.verify_host_key_dns) {
+		/*
+		 * XXX certs are not yet supported for DNS, so downgrade
+		 * them and try the plain key.
+		 */
+		plain = key_from_private(host_key);
+		if (key_is_cert(plain))
+			key_drop_cert(plain);
+		if (verify_host_key_dns(host, hostaddr, plain, &flags) == 0) {
+			if (flags & DNS_VERIFY_FOUND) {
+				if (options.verify_host_key_dns == 1 &&
+				    flags & DNS_VERIFY_MATCH &&
+				    flags & DNS_VERIFY_SECURE) {
+					key_free(plain);
+					return 0;
+				}
+				if (flags & DNS_VERIFY_MATCH) {
+					matching_host_key_dns = 1;
+				} else {
+					warn_changed_key(plain);
+					error("Update the SSHFP RR in DNS "
+					    "with the new host key to get rid "
+					    "of this message.");
+				}
 			}
 		}
+		key_free(plain);
 	}
 
 	return check_host_key(host, hostaddr, options.port, host_key, RDRW,
diff --git a/sys/conf/newvers.sh b/sys/conf/newvers.sh
index 3b7d9afe5035..658f8a57cc7a 100644
--- a/sys/conf/newvers.sh
+++ b/sys/conf/newvers.sh
@@ -32,7 +32,7 @@
 
 TYPE="FreeBSD"
 REVISION="9.3"
-BRANCH="RELEASE-p20"
+BRANCH="RELEASE-p21"
 if [ "X${BRANCH_OVERRIDE}" != "X" ]; then
 	BRANCH=${BRANCH_OVERRIDE}
 fi
diff --git a/sys/netinet/tcp_reass.c b/sys/netinet/tcp_reass.c
index f0af825a52a3..506340d307de 100644
--- a/sys/netinet/tcp_reass.c
+++ b/sys/netinet/tcp_reass.c
@@ -79,25 +79,22 @@ static int tcp_reass_sysctl_qsize(SYSCTL_HANDLER_ARGS);
 static SYSCTL_NODE(_net_inet_tcp, OID_AUTO, reass, CTLFLAG_RW, 0,
     "TCP Segment Reassembly Queue");
 
-static VNET_DEFINE(int, tcp_reass_maxseg) = 0;
-#define	V_tcp_reass_maxseg		VNET(tcp_reass_maxseg)
-SYSCTL_VNET_INT(_net_inet_tcp_reass, OID_AUTO, maxsegments, CTLFLAG_RDTUN,
-    &VNET_NAME(tcp_reass_maxseg), 0,
+static int tcp_reass_maxseg = 0;
+SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, maxsegments, CTLFLAG_RDTUN,
+    &tcp_reass_maxseg, 0,
     "Global maximum number of TCP Segments in Reassembly Queue");
 
-SYSCTL_VNET_PROC(_net_inet_tcp_reass, OID_AUTO, cursegments,
+SYSCTL_PROC(_net_inet_tcp_reass, OID_AUTO, cursegments,
     (CTLTYPE_INT | CTLFLAG_RD), NULL, 0, &tcp_reass_sysctl_qsize, "I",
     "Global number of TCP Segments currently in Reassembly Queue");
 
-static VNET_DEFINE(int, tcp_reass_overflows) = 0;
-#define	V_tcp_reass_overflows		VNET(tcp_reass_overflows)
-SYSCTL_VNET_INT(_net_inet_tcp_reass, OID_AUTO, overflows,
+static int tcp_reass_overflows = 0;
+SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, overflows,
     CTLTYPE_INT | CTLFLAG_RD,
-    &VNET_NAME(tcp_reass_overflows), 0,
+    &tcp_reass_overflows, 0,
     "Global number of TCP Segment Reassembly Queue Overflows");
 
-static VNET_DEFINE(uma_zone_t, tcp_reass_zone);
-#define	V_tcp_reass_zone		VNET(tcp_reass_zone)
+static uma_zone_t tcp_reass_zone;
 
 /* Initialize TCP reassembly queue */
 static void
@@ -105,36 +102,27 @@ tcp_reass_zone_change(void *tag)
 {
 
 	/* Set the zone limit and read back the effective value. */
-	V_tcp_reass_maxseg = nmbclusters / 16;
-	V_tcp_reass_maxseg = uma_zone_set_max(V_tcp_reass_zone,
-	    V_tcp_reass_maxseg);
+	tcp_reass_maxseg = nmbclusters / 16;
+	tcp_reass_maxseg = uma_zone_set_max(tcp_reass_zone,
+	    tcp_reass_maxseg);
 }
 
 void
-tcp_reass_init(void)
+tcp_reass_global_init(void)
 {
 
-	V_tcp_reass_maxseg = nmbclusters / 16;
+	tcp_reass_maxseg = nmbclusters / 16;
 	TUNABLE_INT_FETCH("net.inet.tcp.reass.maxsegments",
-	    &V_tcp_reass_maxseg);
-	V_tcp_reass_zone = uma_zcreate("tcpreass", sizeof (struct tseg_qent),
+	    &tcp_reass_maxseg);
+	tcp_reass_zone = uma_zcreate("tcpreass", sizeof (struct tseg_qent),
 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
 	/* Set the zone limit and read back the effective value. */
-	V_tcp_reass_maxseg = uma_zone_set_max(V_tcp_reass_zone,
-	    V_tcp_reass_maxseg);
+	tcp_reass_maxseg = uma_zone_set_max(tcp_reass_zone,
+	    tcp_reass_maxseg);
 	EVENTHANDLER_REGISTER(nmbclusters_change,
 	    tcp_reass_zone_change, NULL, EVENTHANDLER_PRI_ANY);
 }
 
-#ifdef VIMAGE
-void
-tcp_reass_destroy(void)
-{
-
-	uma_zdestroy(V_tcp_reass_zone);
-}
-#endif
-
 void
 tcp_reass_flush(struct tcpcb *tp)
 {
@@ -145,7 +133,7 @@ tcp_reass_flush(struct tcpcb *tp)
 	while ((qe = LIST_FIRST(&tp->t_segq)) != NULL) {
 		LIST_REMOVE(qe, tqe_q);
 		m_freem(qe->tqe_m);
-		uma_zfree(V_tcp_reass_zone, qe);
+		uma_zfree(tcp_reass_zone, qe);
 		tp->t_segqlen--;
 	}
 
@@ -159,7 +147,7 @@ tcp_reass_sysctl_qsize(SYSCTL_HANDLER_ARGS)
 {
 	int qsize;
 
-	qsize = uma_zone_get_cur(V_tcp_reass_zone);
+	qsize = uma_zone_get_cur(tcp_reass_zone);
 	return (sysctl_handle_int(oidp, &qsize, 0, req));
 }
 
@@ -207,7 +195,7 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m)
 	 */
 	if ((th->th_seq != tp->rcv_nxt || !TCPS_HAVEESTABLISHED(tp->t_state)) &&
 	    tp->t_segqlen >= (so->so_rcv.sb_hiwat / tp->t_maxseg) + 1) {
-		V_tcp_reass_overflows++;
+		tcp_reass_overflows++;
 		TCPSTAT_INC(tcps_rcvmemdrop);
 		m_freem(m);
 		*tlenp = 0;
@@ -226,7 +214,7 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m)
 	 * Use a temporary structure on the stack for the missing segment
 	 * when the zone is exhausted. Otherwise we may get stuck.
 	 */
-	te = uma_zalloc(V_tcp_reass_zone, M_NOWAIT);
+	te = uma_zalloc(tcp_reass_zone, M_NOWAIT);
 	if (te == NULL) {
 		if (th->th_seq != tp->rcv_nxt || !TCPS_HAVEESTABLISHED(tp->t_state)) {
 			TCPSTAT_INC(tcps_rcvmemdrop);
@@ -277,7 +265,7 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m)
 				TCPSTAT_ADD(tcps_rcvdupbyte, *tlenp);
 				m_freem(m);
 				if (te != &tqs)
-					uma_zfree(V_tcp_reass_zone, te);
+					uma_zfree(tcp_reass_zone, te);
 				tp->t_segqlen--;
 				/*
 				 * Try to present any queued data
@@ -314,7 +302,7 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m)
 		nq = LIST_NEXT(q, tqe_q);
 		LIST_REMOVE(q, tqe_q);
 		m_freem(q->tqe_m);
-		uma_zfree(V_tcp_reass_zone, q);
+		uma_zfree(tcp_reass_zone, q);
 		tp->t_segqlen--;
 		q = nq;
 	}
@@ -353,7 +341,7 @@ present:
 		else
 			sbappendstream_locked(&so->so_rcv, q->tqe_m);
 		if (q != &tqs)
-			uma_zfree(V_tcp_reass_zone, q);
+			uma_zfree(tcp_reass_zone, q);
 		tp->t_segqlen--;
 		q = nq;
 	} while (q && q->tqe_th->th_seq == tp->rcv_nxt);
diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index 8f40d0bd58b5..8a81ecb78382 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -314,7 +314,6 @@ tcp_init(void)
 	tcp_tw_init();
 	syncache_init();
 	tcp_hc_init();
-	tcp_reass_init();
 
 	TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack);
 	V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole),
@@ -324,6 +323,8 @@ tcp_init(void)
 	if (!IS_DEFAULT_VNET(curvnet))
 		return;
 
+	tcp_reass_global_init();
+
 	/* XXX virtualize those bellow? */
 	tcp_delacktime = TCPTV_DELACK;
 	tcp_keepinit = TCPTV_KEEP_INIT;
@@ -371,7 +372,6 @@ void
 tcp_destroy(void)
 {
 
-	tcp_reass_destroy();
 	tcp_hc_destroy();
 	syncache_destroy();
 	tcp_tw_destroy();
diff --git a/sys/netinet/tcp_var.h b/sys/netinet/tcp_var.h
index 171eafb6d8b0..6ecac51c5b4d 100644
--- a/sys/netinet/tcp_var.h
+++ b/sys/netinet/tcp_var.h
@@ -680,11 +680,8 @@ char	*tcp_log_addrs(struct in_conninfo *, struct tcphdr *, void *,
 char	*tcp_log_vain(struct in_conninfo *, struct tcphdr *, void *,
 	    const void *);
 int	 tcp_reass(struct tcpcb *, struct tcphdr *, int *, struct mbuf *);
-void	 tcp_reass_init(void);
+void	 tcp_reass_global_init(void);
 void	 tcp_reass_flush(struct tcpcb *);
-#ifdef VIMAGE
-void	 tcp_reass_destroy(void);
-#endif
 void	 tcp_input(struct mbuf *, int);
 u_long	 tcp_maxmtu(struct in_conninfo *, struct tcp_ifcap *);
 u_long	 tcp_maxmtu6(struct in_conninfo *, struct tcp_ifcap *);