From: Miod Vallat <miod.vallat@powerdns.com>
Date: Mon, 16 Jun 2025 06:22:24 +0000 (+0200)
Subject: Force callers of getMDBEnv() to always specify the maximum map size.
X-Git-Tag: auth-4.9.6~3^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=30c71d3a7747758c19ac378fd55e106998100be5;p=thirdparty%2Fpdns.git

Force callers of getMDBEnv() to always specify the maximum map size.

Fixes: #12901

Signed-off-by: Miod Vallat <miod.vallat@powerdns.com>
(cherry picked from commit 862702653299ba91580acdf2bfa8ab09c29362b5)
---

diff --git a/ext/lmdb-safe/lmdb-safe.hh b/ext/lmdb-safe/lmdb-safe.hh
index 4370fb31b7..25498ff5ea 100644
--- a/ext/lmdb-safe/lmdb-safe.hh
+++ b/ext/lmdb-safe/lmdb-safe.hh
@@ -107,7 +107,7 @@ private:
   std::map<std::thread::id, int> d_ROtransactionsOut;
 };
 
-std::shared_ptr<MDBEnv> getMDBEnv(const char* fname, int flags, int mode, uint64_t mapsizeMB=(sizeof(void *)==4) ? 100 : 16000);
+std::shared_ptr<MDBEnv> getMDBEnv(const char* fname, int flags, int mode, uint64_t mapsizeMB);
 
 #ifndef DNSDIST
 
diff --git a/modules/lmdbbackend/lmdbbackend.cc b/modules/lmdbbackend/lmdbbackend.cc
index 6fe78abe4a..82f4d60339 100644
--- a/modules/lmdbbackend/lmdbbackend.cc
+++ b/modules/lmdbbackend/lmdbbackend.cc
@@ -665,9 +665,9 @@ LMDBBackend::LMDBBackend(const std::string& suffix)
   else
     throw std::runtime_error("Unknown sync mode " + syncMode + " requested for LMDB backend");
 
-  uint64_t mapSize = 0;
+  d_mapsize = 0;
   try {
-    mapSize = std::stoll(getArg("map-size"));
+    d_mapsize = std::stoll(getArg("map-size"));
   }
   catch (const std::exception& e) {
     throw std::runtime_error(std::string("Unable to parse the 'map-size' LMDB value: ") + e.what());
@@ -723,7 +723,7 @@ LMDBBackend::LMDBBackend(const std::string& suffix)
         throw std::runtime_error("Somehow, we are not at schema version 5. Giving up");
       }
 
-      d_tdomains = std::make_shared<tdomains_t>(getMDBEnv(getArg("filename").c_str(), MDB_NOSUBDIR | d_asyncFlag, 0600, mapSize), "domains_v5");
+      d_tdomains = std::make_shared<tdomains_t>(getMDBEnv(getArg("filename").c_str(), MDB_NOSUBDIR | d_asyncFlag, 0600, d_mapsize), "domains_v5");
       d_tmeta = std::make_shared<tmeta_t>(d_tdomains->getEnv(), "metadata_v5");
       d_tkdb = std::make_shared<tkdb_t>(d_tdomains->getEnv(), "keydata_v5");
       d_ttsig = std::make_shared<ttsig_t>(d_tdomains->getEnv(), "tsig_v5");
@@ -770,7 +770,7 @@ LMDBBackend::LMDBBackend(const std::string& suffix)
   }
 
   if (!opened) {
-    d_tdomains = std::make_shared<tdomains_t>(getMDBEnv(getArg("filename").c_str(), MDB_NOSUBDIR | d_asyncFlag, 0600, mapSize), "domains_v5");
+    d_tdomains = std::make_shared<tdomains_t>(getMDBEnv(getArg("filename").c_str(), MDB_NOSUBDIR | d_asyncFlag, 0600, d_mapsize), "domains_v5");
     d_tmeta = std::make_shared<tmeta_t>(d_tdomains->getEnv(), "metadata_v5");
     d_tkdb = std::make_shared<tkdb_t>(d_tdomains->getEnv(), "keydata_v5");
     d_ttsig = std::make_shared<ttsig_t>(d_tdomains->getEnv(), "tsig_v5");
@@ -1211,7 +1211,7 @@ std::shared_ptr<LMDBBackend::RecordsRWTransaction> LMDBBackend::getRecordsRWTran
   auto& shard = d_trecords[id % s_shards];
   if (!shard.env) {
     shard.env = getMDBEnv((getArg("filename") + "-" + std::to_string(id % s_shards)).c_str(),
-                          MDB_NOSUBDIR | d_asyncFlag, 0600);
+                          MDB_NOSUBDIR | d_asyncFlag, 0600, d_mapsize);
     shard.dbi = shard.env->openDB("records_v5", MDB_CREATE);
   }
   auto ret = std::make_shared<RecordsRWTransaction>(shard.env->getRWTransaction());
@@ -1228,7 +1228,7 @@ std::shared_ptr<LMDBBackend::RecordsROTransaction> LMDBBackend::getRecordsROTran
       throw DBException("attempting to start nested transaction without open parent env");
     }
     shard.env = getMDBEnv((getArg("filename") + "-" + std::to_string(id % s_shards)).c_str(),
-                          MDB_NOSUBDIR | d_asyncFlag, 0600);
+                          MDB_NOSUBDIR | d_asyncFlag, 0600, d_mapsize);
     shard.dbi = shard.env->openDB("records_v5", MDB_CREATE);
   }
 
diff --git a/modules/lmdbbackend/lmdbbackend.hh b/modules/lmdbbackend/lmdbbackend.hh
index 40f18f8fb3..4df9c34cbe 100644
--- a/modules/lmdbbackend/lmdbbackend.hh
+++ b/modules/lmdbbackend/lmdbbackend.hh
@@ -333,4 +333,5 @@ private:
   bool d_random_ids;
   bool d_handle_dups;
   DTime d_dtime; // used only for logging
+  uint64_t d_mapsize;
 };