Fix off-by-one bug in ISC SPNEGO implementation (#1929965)

Because of other failures in rebase, doing just security patch this
time.

bind-9.16-CVE-2020-8625.patch

@@ -0,0 +1,45 @@
+From b04cb88462863d762093760ffcfe1946200e30f5 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Ond=C5=99ej=20Sur=C3=BD?= <ondrej@isc.org>
+Date: Thu, 7 Jan 2021 10:44:46 +0100
+Subject: [PATCH] Fix off-by-one bug in ISC SPNEGO implementation
+
+The ISC SPNEGO implementation is based on mod_auth_kerb code.  When
+CVE-2006-5989 was disclosed, the relevant fix was not applied to the
+BIND 9 codebase, making the latter vulnerable to the aforementioned flaw
+when "tkey-gssapi-keytab" or "tkey-gssapi-credential" is set in
+named.conf.
+
+The original description of CVE-2006-5989 was:
+
+    Off-by-one error in the der_get_oid function in mod_auth_kerb 5.0
+    allows remote attackers to cause a denial of service (crash) via a
+    crafted Kerberos message that triggers a heap-based buffer overflow
+    in the component array.
+
+Later research revealed that this flaw also theoretically enables remote
+code execution, though achieving the latter in real-world conditions is
+currently deemed very difficult.
+
+This vulnerability was responsibly reported as ZDI-CAN-12302 ("ISC BIND
+TKEY Query Heap-based Buffer Overflow Remote Code Execution
+Vulnerability") by Trend Micro Zero Day Initiative.
+---
+ lib/dns/spnego.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/lib/dns/spnego.c b/lib/dns/spnego.c
+index e61d1c600f..753dc8049f 100644
+--- a/lib/dns/spnego.c
++++ b/lib/dns/spnego.c
+@@ -848,7 +848,7 @@ der_get_oid(const unsigned char *p, size_t len, oid *data, size_t *size) {
+ 		return (ASN1_OVERRUN);
+ 	}
+ 
+-	data->components = malloc(len * sizeof(*data->components));
++	data->components = malloc((len + 1) * sizeof(*data->components));
+ 	if (data->components == NULL) {
+ 		return (ENOMEM);
+ 	}
+-- 
+2.26.2
+

bind.spec

@@ -66,7 +66,7 @@ Summary:  The Berkeley Internet Name Domain (BIND) DNS (Domain Name System) serv
 Name:     bind
 License:  MPLv2.0
 Version:  9.16.11
-Release:  3%{?PATCHVER:.%{PATCHVER}}%{?PREVER:.%{PREVER}}%{?dist}
+Release:  4%{?PATCHVER:.%{PATCHVER}}%{?PREVER:.%{PREVER}}%{?dist}
 Epoch:    32
 Url:      https://www.isc.org/downloads/bind/
 #
@@ -120,6 +120,8 @@ Patch170:bind-9.11-feature-test-named.patch
 Patch171:bind-9.11-tests-variants.patch
 # https://gitlab.isc.org/isc-projects/bind9/-/merge_requests/4582
 Patch172:bind-9.16-unit-tests-multicore.patch
+# https://gitlab.isc.org/isc-projects/bind9/commit/b04cb88462863d762093760ffcfe1946200e30f5
+Patch173:bind-9.16-CVE-2020-8625.patch
 
 Requires(post):   systemd
 Requires(preun):  systemd
@@ -434,6 +436,7 @@ in HTML and PDF format.
 %patch170 -p1 -b .featuretest-named
 %patch171 -p1 -b .test-variant
 %patch172 -p1 -b .multicore
+%patch173 -p1 -b .CVE-2020-8625
 
 %if %{with PKCS11}
 %patch135 -p1 -b .config-pkcs11
@@ -1164,6 +1167,9 @@ fi;
 %endif
 
 %changelog
+* Mon Feb 22 2021 Petr Menšík <pemensik@redhat.com> - 32:9.16.11-4
+- Fix off-by-one bug in ISC SPNEGO implementation (#1929965)
+
 * Mon Feb 08 2021 Pavel Raiskup <praiskup@redhat.com> - 32:9.16.11-3
 - rebuild for libpq ABI fix rhbz#1908268