bind/backport-CVE-2021-25219.patch
jiangheng 9004379e30 fix CVE-2021-25219
(cherry picked from commit a6d982af8b28ff6433c2bd883d82158bff8ba93d)
2021-11-16 15:08:09 +08:00

70 lines
2.4 KiB
Diff

Conflict: is_lame(fctx, rmessage) to is_lame(fctx)
Reference : https://downloads.isc.org/bind9/cur/9.11/patches/CVE-2021-25219.patch
diff --git a/bin/named/config.c b/bin/named/config.c
index fbd2f2126c..d24e4f8a26 100644
--- a/bin/named/config.c
+++ b/bin/named/config.c
@@ -175,7 +175,7 @@ options {\n\
#if defined(HAVE_GEOIP) || defined(HAVE_GEOIP2)
" geoip-use-ecs yes;\n"
#endif
-" lame-ttl 600;\n"
+" lame-ttl 0;\n"
#ifdef HAVE_LMDB
" lmdb-mapsize 32M;\n"
#endif
diff --git a/bin/named/server.c b/bin/named/server.c
index 6ff95e3bcc..9826588e6d 100644
--- a/bin/named/server.c
+++ b/bin/named/server.c
@@ -3987,8 +3987,12 @@ configure_view(dns_view_t *view, dns_viewlist_t *viewlist,
result = ns_config_get(maps, "lame-ttl", &obj);
INSIST(result == ISC_R_SUCCESS);
lame_ttl = cfg_obj_asuint32(obj);
- if (lame_ttl > 1800)
- lame_ttl = 1800;
+ if (lame_ttl > 0) {
+ cfg_obj_log(obj, ns_g_lctx, ISC_LOG_WARNING,
+ "disabling lame cache despite lame-ttl > 0 as it "
+ "may cause performance issues");
+ lame_ttl = 0;
+ }
dns_resolver_setlamettl(view->resolver, lame_ttl);
/*
diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index 8175f7918b..b34cb12b73 100644
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -8489,18 +8489,20 @@ resquery_response(isc_task_t *task, isc_event_t *event) {
/*
* Is the server lame?
*/
- if (res->lame_ttl != 0 && !ISFORWARDER(query->addrinfo) &&
- is_lame(fctx)) {
+ if (!ISFORWARDER(query->addrinfo) && is_lame(fctx)) {
inc_stats(res, dns_resstatscounter_lame);
log_lame(fctx, query->addrinfo);
- result = dns_adb_marklame(fctx->adb, query->addrinfo,
- &fctx->name, fctx->type,
- now + res->lame_ttl);
- if (result != ISC_R_SUCCESS)
- isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER,
- DNS_LOGMODULE_RESOLVER, ISC_LOG_ERROR,
- "could not mark server as lame: %s",
- isc_result_totext(result));
+ if (res->lame_ttl != 0) {
+ result = dns_adb_marklame(fctx->adb, query->addrinfo,
+ &fctx->name, fctx->type,
+ now + res->lame_ttl);
+ if (result != ISC_R_SUCCESS) {
+ isc_log_write(dns_lctx, DNS_LOGCATEGORY_RESOLVER,
+ DNS_LOGMODULE_RESOLVER, ISC_LOG_ERROR,
+ "could not mark server as lame: %s",
+ isc_result_totext(result));
+ }
+ }
broken_server = DNS_R_LAME;
keep_trying = true;
FCTXTRACE("lame server");