From 490b2b4c90fab105c40ec14756de18a13b99f897 Mon Sep 17 00:00:00 2001
From: Volker Hilsheimer <volker.hilsheimer@qt.io>
Date: Wed, 13 Nov 2024 14:50:18 +0100
Subject: [PATCH] QJniArray: fix local reference leak

We get a local reference from New*Array, and then construct a QJniArray
from that, which will create a new global reference, without deleting
the local reference.

Instead, go through QJniObject::fromLocalRef, and release the local
reference also in case of failure.

Change-Id: I88108315240133369efab30e55fdbea17a17a26d
Reviewed-by: Assam Boudjelthia <assam.boudjelthia@qt.io>
Reviewed-by: Zoltan Gera <zoltan.gera@qt.io>
(cherry picked from commit 37638c84efaf2810ad49da0b987f19287d8c4ad6)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/corelib/kernel/qjniarray.h | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/corelib/kernel/qjniarray.h b/src/corelib/kernel/qjniarray.h
index 7dbd3d475d2..a7dc03694d2 100644
--- a/src/corelib/kernel/qjniarray.h
+++ b/src/corelib/kernel/qjniarray.h
@@ -578,8 +578,11 @@ auto QJniArrayBase::makeArray(List &&list, NewFn &&newArray, SetFn &&setRegion)
     const size_type length = size_type(std::size(list));
     JNIEnv *env = QJniEnvironment::getJniEnv();
     auto localArray = (env->*newArray)(length);
-    if (QJniEnvironment::checkAndClearExceptions(env))
+    if (QJniEnvironment::checkAndClearExceptions(env)) {
+        if (localArray)
+            env->DeleteLocalRef(localArray);
         return QJniArray<ElementType>();
+    }
 
     if (length) {
         // can't use static_cast here because we have signed/unsigned mismatches
@@ -592,7 +595,7 @@ auto QJniArrayBase::makeArray(List &&list, NewFn &&newArray, SetFn &&setRegion)
                 (env->*setRegion)(localArray, i++, 1, reinterpret_cast<const ElementType *>(&e));
         }
     }
-    return QJniArray<ElementType>(localArray);
+    return QJniArray<ElementType>(QJniObject::fromLocalRef(localArray));
 };
 
 template <typename List>
@@ -620,8 +623,11 @@ auto QJniArrayBase::makeObjectArray(List &&list)
         elementClass = env->GetObjectClass(*std::begin(list));
     }
     auto localArray = env->NewObjectArray(length, elementClass, nullptr);
-    if (QJniEnvironment::checkAndClearExceptions(env))
+    if (QJniEnvironment::checkAndClearExceptions(env)) {
+        if (localArray)
+            env->DeleteLocalRef(localArray);
         return ResultType();
+    }
 
     // explicitly manage the frame for local references in chunks of 100
     QJniObject::LocalFrame frame(env);
@@ -640,7 +646,7 @@ auto QJniArrayBase::makeObjectArray(List &&list)
     }
     if (i)
         env->PopLocalFrame(nullptr);
-    return ResultType(localArray);
+    return ResultType(QJniObject::fromLocalRef(localArray));
 }
 
 namespace QtJniTypes