File bind-CVE-2015-8000.patch of Package bind.1720
@@ -, +, @@
4260. [security] Insufficient testing when parsing a message allowed
records with an incorrect class to be be accepted,
triggering a REQUIRE failure when those records
were subsequently cached. (CVE-2015-8000) [RT #4098]
(cherry picked from commit c8821d124c532e0a65752b378f924d4259499fd3)
(cherry picked from commit 9631d0769e09c823acb68ed9795f220bf37800ca)
Index: bind-9.9.6-P1/CHANGES
===================================================================
--- bind-9.9.6-P1.orig/CHANGES
+++ bind-9.9.6-P1/CHANGES
@@ -1,3 +1,8 @@
+4260. [security] Insufficient testing when parsing a message allowed
+ records with an incorrect class to be be accepted,
+ triggering a REQUIRE failure when those records
+ were subsequently cached. (CVE-2015-8000) [RT #4098]
+
--- 9.9.6-P1 released ---
4006. [security] A flaw in delegation handling could be exploited
Index: bind-9.9.6-P1/bin/tests/system/start.pl
===================================================================
--- bind-9.9.6-P1.orig/bin/tests/system/start.pl
+++ bind-9.9.6-P1/bin/tests/system/start.pl
@@ -68,6 +68,7 @@
my $LWRESD = $ENV{'LWRESD'};
my $DIG = $ENV{'DIG'};
my $PERL = $ENV{'PERL'};
+my $PYTHON = $ENV{'PYTHON'};
# Start the server(s)
@@ -188,7 +189,9 @@
$pid_file = "lwresd.pid";
} elsif ($server =~ /^ans/) {
$cleanup_files = "{ans.run}";
- if (-e "$testdir/$server/ans.pl") {
+ if (-e "$testdir/$server/ans.py") {
+ $command = "$PYTHON ans.py 10.53.0.$' 5300";
+ } elsif (-e "$testdir/$server/ans.pl") {
$command = "$PERL ans.pl";
} else {
$command = "$PERL $topdir/ans.pl 10.53.0.$'";
Index: bind-9.9.6-P1/lib/dns/include/dns/message.h
===================================================================
--- bind-9.9.6-P1.orig/lib/dns/include/dns/message.h
+++ bind-9.9.6-P1/lib/dns/include/dns/message.h
@@ -15,8 +15,6 @@
* PERFORMANCE OF THIS SOFTWARE.
*/
-/* $Id$ */
-
#ifndef DNS_MESSAGE_H
#define DNS_MESSAGE_H 1
@@ -215,6 +213,8 @@
unsigned int verify_attempted : 1;
unsigned int free_query : 1;
unsigned int free_saved : 1;
+ unsigned int tkey : 1;
+ unsigned int rdclass_set : 1;
unsigned int opt_reserved;
unsigned int sig_reserved;
@@ -1379,6 +1379,15 @@
* \li other.
*/
+void
+dns_message_setclass(dns_message_t *msg, dns_rdataclass_t rdclass);
+/*%<
+ * Set the expected class of records in the response.
+ *
+ * Requires:
+ * \li msg be a valid message with parsing intent.
+ */
+
ISC_LANG_ENDDECLS
#endif /* DNS_MESSAGE_H */
Index: bind-9.9.6-P1/lib/dns/message.c
===================================================================
--- bind-9.9.6-P1.orig/lib/dns/message.c
+++ bind-9.9.6-P1/lib/dns/message.c
@@ -436,6 +436,8 @@
m->saved.base = NULL;
m->saved.length = 0;
m->free_saved = 0;
+ m->tkey = 0;
+ m->rdclass_set = 0;
m->querytsig = NULL;
}
@@ -1086,13 +1088,19 @@
* If this class is different than the one we already read,
* this is an error.
*/
- if (msg->state == DNS_SECTION_ANY) {
- msg->state = DNS_SECTION_QUESTION;
+ if (msg->rdclass_set == 0) {
msg->rdclass = rdclass;
+ msg->rdclass_set = 1;
} else if (msg->rdclass != rdclass)
DO_FORMERR;
/*
+ * Is this a TKEY query?
+ */
+ if (rdtype == dns_rdatatype_tkey)
+ msg->tkey = 1;
+
+ /*
* Can't ask the same question twice.
*/
result = dns_message_find(name, rdclass, rdtype, 0, NULL);
@@ -1236,12 +1244,12 @@
* If there was no question section, we may not yet have
* established a class. Do so now.
*/
- if (msg->state == DNS_SECTION_ANY &&
+ if (msg->rdclass_set == 0 &&
rdtype != dns_rdatatype_opt && /* class is UDP SIZE */
rdtype != dns_rdatatype_tsig && /* class is ANY */
rdtype != dns_rdatatype_tkey) { /* class is undefined */
msg->rdclass = rdclass;
- msg->state = DNS_SECTION_QUESTION;
+ msg->rdclass_set = 1;
}
/*
@@ -1251,7 +1259,7 @@
if (msg->opcode != dns_opcode_update
&& rdtype != dns_rdatatype_tsig
&& rdtype != dns_rdatatype_opt
- && rdtype != dns_rdatatype_dnskey /* in a TKEY query */
+ && rdtype != dns_rdatatype_key /* in a TKEY query */
&& rdtype != dns_rdatatype_sig /* SIG(0) */
&& rdtype != dns_rdatatype_tkey /* Win2000 TKEY */
&& msg->rdclass != dns_rdataclass_any
@@ -1259,6 +1267,16 @@
DO_FORMERR;
/*
+ * If this is not a TKEY query/response then the KEY
+ * record's class needs to match.
+ */
+ if (msg->opcode != dns_opcode_update && !msg->tkey &&
+ rdtype == dns_rdatatype_key &&
+ msg->rdclass != dns_rdataclass_any &&
+ msg->rdclass != rdclass)
+ DO_FORMERR;
+
+ /*
* Special type handling for TSIG, OPT, and TKEY.
*/
if (rdtype == dns_rdatatype_tsig) {
@@ -1372,6 +1390,10 @@
skip_name_search = ISC_TRUE;
skip_type_search = ISC_TRUE;
issigzero = ISC_TRUE;
+ } else {
+ if (msg->rdclass != dns_rdataclass_any &&
+ msg->rdclass != rdclass)
+ DO_FORMERR;
}
} else
covers = 0;
@@ -1620,6 +1642,7 @@
msg->counts[DNS_SECTION_ADDITIONAL] = isc_buffer_getuint16(source);
msg->header_ok = 1;
+ msg->state = DNS_SECTION_QUESTION;
/*
* -1 means no EDNS.
@@ -3564,3 +3587,15 @@
dns_message_puttemprdatalist(message, &rdatalist);
return (result);
}
+
+void
+dns_message_setclass(dns_message_t *msg, dns_rdataclass_t rdclass) {
+
+ REQUIRE(DNS_MESSAGE_VALID(msg));
+ REQUIRE(msg->from_to_wire == DNS_MESSAGE_INTENTPARSE);
+ REQUIRE(msg->state == DNS_SECTION_ANY);
+ REQUIRE(msg->rdclass_set == 0);
+
+ msg->rdclass = rdclass;
+ msg->rdclass_set = 1;
+}
Index: bind-9.9.6-P1/lib/dns/resolver.c
===================================================================
--- bind-9.9.6-P1.orig/lib/dns/resolver.c
+++ bind-9.9.6-P1/lib/dns/resolver.c
@@ -6983,6 +6983,8 @@
goto done;
}
+ dns_message_setclass(message, fctx->res->rdclass);
+
result = dns_message_parse(message, &devent->buffer, 0);
if (result != ISC_R_SUCCESS) {
switch (result) {
@@ -7055,6 +7057,12 @@
*/
log_packet(message, ISC_LOG_DEBUG(10), fctx->res->mctx);
+ if (message->rdclass != fctx->res->rdclass) {
+ resend = ISC_TRUE;
+ FCTXTRACE("bad class");
+ goto done;
+ }
+
/*
* Process receive opt record.
*/
Index: bind-9.9.6-P1/lib/dns/xfrin.c
===================================================================
--- bind-9.9.6-P1.orig/lib/dns/xfrin.c
+++ bind-9.9.6-P1/lib/dns/xfrin.c
@@ -1211,6 +1211,8 @@
msg->tsigctx = xfr->tsigctx;
xfr->tsigctx = NULL;
+ dns_message_setclass(msg, xfr->rdclass);
+
if (xfr->nmsg > 0)
msg->tcp_continuation = 1;
