From b75e16f4f85fd54048db02dfd00edeb561b4d183 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=9B=D0=B5=D0=BE=D0=BD=D0=B8=D0=B4=20=D0=AE=D1=80=D1=8C?=
 =?UTF-8?q?=D0=B5=D0=B2=20=28Leonid=20Yuriev=29?= <leo@yuriev.ru>
Date: Sat, 11 Jan 2025 23:16:55 +0300
Subject: [PATCH] =?UTF-8?q?mdbx:=20=D1=83=D1=81=D1=82=D1=80=D0=B0=D0=BD?=
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---
 src/lck-posix.c | 11 ++++++++---
 src/txn.c       |  2 +-
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/lck-posix.c b/src/lck-posix.c
index 4cf83c46..41f49f48 100644
--- a/src/lck-posix.c
+++ b/src/lck-posix.c
@@ -823,10 +823,11 @@ MDBX_INTERNAL void lck_rdt_unlock(MDBX_env *env) {
 
 int lck_txn_lock(MDBX_env *env, bool dont_wait) {
   TRACE("%swait %s", dont_wait ? "dont-" : "", ">>");
+  eASSERT(env, env->basal_txn || (env->lck == lckless_stub(env) && (env->flags & MDBX_RDONLY)));
   jitter4testing(true);
   const int err = osal_ipclock_lock(env, &env->lck->wrt_lock, dont_wait);
   int rc = err;
-  if (likely(!MDBX_IS_ERROR(err))) {
+  if (likely(env->basal_txn && !MDBX_IS_ERROR(err))) {
     eASSERT(env, !env->basal_txn->owner || err == /* если другой поток в этом-же процессе завершился
                                                      не освободив блокировку */
                                                MDBX_RESULT_TRUE);
@@ -839,8 +840,12 @@ int lck_txn_lock(MDBX_env *env, bool dont_wait) {
 
 void lck_txn_unlock(MDBX_env *env) {
   TRACE("%s", ">>");
-  eASSERT(env, env->basal_txn->owner == osal_thread_self());
-  env->basal_txn->owner = 0;
+  if (env->basal_txn) {
+    eASSERT(env, !env->basal_txn || env->basal_txn->owner == osal_thread_self());
+    env->basal_txn->owner = 0;
+  } else {
+    eASSERT(env, env->lck == lckless_stub(env) && (env->flags & MDBX_RDONLY));
+  }
   int err = osal_ipclock_unlock(env, &env->lck->wrt_lock);
   TRACE("<< err %d", err);
   if (unlikely(err != MDBX_SUCCESS))
diff --git a/src/txn.c b/src/txn.c
index db3af6ed..478f4d07 100644
--- a/src/txn.c
+++ b/src/txn.c
@@ -503,7 +503,7 @@ int txn_renew(MDBX_txn *txn, unsigned flags) {
       txn->flags = MDBX_TXN_RDONLY | MDBX_TXN_FINISHED;
       return MDBX_SUCCESS;
     }
-    txn->owner = (uintptr_t)r->tid.weak;
+    txn->owner = likely(r) ? (uintptr_t)r->tid.weak : ((env->flags & MDBX_NOSTICKYTHREADS) ? 0 : osal_thread_self());
     if ((env->flags & MDBX_NOSTICKYTHREADS) == 0 && env->txn && unlikely(env->basal_txn->owner == txn->owner) &&
         (globals.runtime_flags & MDBX_DBG_LEGACY_OVERLAP) == 0)
       return MDBX_TXN_OVERLAPPING;