From: Otto Moerbeek <otto.moerbeek@open-xchange.com>
Date: Tue, 20 Dec 2022 11:30:54 +0000 (+0100)
Subject: Use correct logic for isEntryUsable()
X-Git-Tag: dnsdist-1.8.0-rc1~148^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=24f2f86f94f685bba01a8a10b2a1f3185ba3cff1;p=thirdparty%2Fpdns.git

Use correct logic for isEntryUsable()

Existing code was correct but used the wrong name for the method:
isEntryUsable() actually tested for isUnusable, but the caller
compensated for it. Reverse logic to make it more clear.
---

diff --git a/pdns/recursordist/recursor_cache.cc b/pdns/recursordist/recursor_cache.cc
index c2ef9ce34b..8f9e440f4d 100644
--- a/pdns/recursordist/recursor_cache.cc
+++ b/pdns/recursordist/recursor_cache.cc
@@ -418,7 +418,7 @@ time_t MemRecursorCache::get(time_t now, const DNSName& qname, const QType qt, F
         firstIndexIterator = map->d_map.project<OrderedTag>(i);
 
         // When serving stale, we consider expired records
-        if (i->isEntryUsable(now, serveStale)) {
+        if (!i->isEntryUsable(now, serveStale)) {
           moveCacheItemToFront<SequencedTag>(map->d_map, firstIndexIterator);
           continue;
         }
@@ -459,7 +459,7 @@ time_t MemRecursorCache::get(time_t now, const DNSName& qname, const QType qt, F
       firstIndexIterator = map->d_map.project<OrderedTag>(i);
 
       // When serving stale, we consider expired records
-      if (i->isEntryUsable(now, serveStale)) {
+      if (!i->isEntryUsable(now, serveStale)) {
         moveCacheItemToFront<SequencedTag>(map->d_map, firstIndexIterator);
         continue;
       }
diff --git a/pdns/recursordist/recursor_cache.hh b/pdns/recursordist/recursor_cache.hh
index d191d1ac32..bd3b0eb859 100644
--- a/pdns/recursordist/recursor_cache.hh
+++ b/pdns/recursordist/recursor_cache.hh
@@ -104,7 +104,7 @@ private:
     bool isEntryUsable(time_t now, bool serveStale) const
     {
       // When serving stale, we consider expired records
-      return d_ttd <= now && !serveStale && d_servedStale == 0;
+      return d_ttd > now || serveStale || d_servedStale != 0;
     }
 
     bool shouldReplace(time_t now, bool auth, vState state, bool refresh);