Fix Bluez LE advertiser delete crash

Bluez LE advertiser and Bluez LE controller use/share an instance of
HCI manager, and in some circumstances the deletion of the LE controller
leads to a crash. This is because:
1) LE advertiser and HCI manager are parented to the LE controller
2) LE advertiser uses HCI manager in its destructor
=> When LE controller is deleted, its QObject children are deleted.
   If the HCI manager happens to be deleted first, the advertiser uses
   a by-now deleted HCI manager in its destructor

This commit makes the HCI manager a shared resource so that the exact
destruction order does not matter.

As a drive-by set deleted cmacCalculator pointer to nullptr.

Fixes: QTBUG-104105
Change-Id: I1c5e319af2fc59c4d5bb1fed33b8824eb3c4cb29
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
(cherry picked from commit f1ff9f4d17b82b5e597e28118de62beab705519e)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

6 files changed, 22 insertions, 17 deletions

diff --git a/src/bluetooth/bluez/hcimanager.cpp b/src/bluetooth/bluez/hcimanager.cpp
index 82dcc831..65cbd80e 100644
--- a/src/bluetooth/bluez/hcimanager.cpp
+++ b/src/bluetooth/bluez/hcimanager.cpp
@@ -21,8 +21,8 @@ QT_BEGIN_NAMESPACE
 
 Q_DECLARE_LOGGING_CATEGORY(QT_BT_BLUEZ)
 
-HciManager::HciManager(const QBluetoothAddress& deviceAdapter, QObject *parent) :
-    QObject(parent), hciSocket(-1), hciDev(-1)
+HciManager::HciManager(const QBluetoothAddress& deviceAdapter) :
+    QObject(nullptr), hciSocket(-1), hciDev(-1)
 {
     hciSocket = ::socket(AF_BLUETOOTH, SOCK_RAW | SOCK_CLOEXEC, BTPROTO_HCI);
     if (hciSocket < 0) {
diff --git a/src/bluetooth/bluez/hcimanager_p.h b/src/bluetooth/bluez/hcimanager_p.h
index 4fb107e7..161675f3 100644
--- a/src/bluetooth/bluez/hcimanager_p.h
+++ b/src/bluetooth/bluez/hcimanager_p.h
@@ -156,7 +156,7 @@ public:
     };
     Q_ENUM(HciError);
 
-    explicit HciManager(const QBluetoothAddress &deviceAdapter, QObject *parent = nullptr);
+    explicit HciManager(const QBluetoothAddress &deviceAdapter);
     ~HciManager();
 
     bool isValid() const;
diff --git a/src/bluetooth/qleadvertiser_bluez.cpp b/src/bluetooth/qleadvertiser_bluez.cpp
index e4a1beea..ebf75b9f 100644
--- a/src/bluetooth/qleadvertiser_bluez.cpp
+++ b/src/bluetooth/qleadvertiser_bluez.cpp
@@ -49,23 +49,24 @@ static QByteArray byteArrayFromStruct(const T &data)
 QLeAdvertiserBluez::QLeAdvertiserBluez(const QLowEnergyAdvertisingParameters &params,
                                        const QLowEnergyAdvertisingData &advertisingData,
                                        const QLowEnergyAdvertisingData &scanResponseData,
-                                       HciManager &hciManager, QObject *parent)
+                                       std::shared_ptr<HciManager> hciManager, QObject *parent)
     : QLeAdvertiser(params, advertisingData, scanResponseData, parent), m_hciManager(hciManager)
 {
-    connect(&m_hciManager, &HciManager::commandCompleted, this,
+    Q_ASSERT(m_hciManager);
+    connect(m_hciManager.get(), &HciManager::commandCompleted, this,
             &QLeAdvertiserBluez::handleCommandCompleted);
 }
 
 QLeAdvertiserBluez::~QLeAdvertiserBluez()
 {
-    disconnect(&m_hciManager, &HciManager::commandCompleted, this,
+    disconnect(m_hciManager.get(), &HciManager::commandCompleted, this,
                &QLeAdvertiserBluez::handleCommandCompleted);
     doStopAdvertising();
 }
 
 void QLeAdvertiserBluez::doStartAdvertising()
 {
-    if (!m_hciManager.monitorEvent(HciManager::HciEvent::EVT_CMD_COMPLETE)) {
+    if (!m_hciManager->monitorEvent(HciManager::HciEvent::EVT_CMD_COMPLETE)) {
         handleError();
         return;
     }
@@ -97,7 +98,7 @@ void QLeAdvertiserBluez::sendNextCommand()
         return;
     }
     const Command &c = m_pendingCommands.first();
-    if (!m_hciManager.sendCommand(QBluezConst::OgfLinkControl, c.ocf, c.data)) {
+    if (!m_hciManager->sendCommand(QBluezConst::OgfLinkControl, c.ocf, c.data)) {
         handleError();
         return;
     }
diff --git a/src/bluetooth/qleadvertiser_bluez_p.h b/src/bluetooth/qleadvertiser_bluez_p.h
index b7227578..5bb5d968 100644
--- a/src/bluetooth/qleadvertiser_bluez_p.h
+++ b/src/bluetooth/qleadvertiser_bluez_p.h
@@ -68,7 +68,8 @@ class QLeAdvertiserBluez : public QLeAdvertiser
 public:
     QLeAdvertiserBluez(const QLowEnergyAdvertisingParameters &params,
                        const QLowEnergyAdvertisingData &advertisingData,
-                       const QLowEnergyAdvertisingData &scanResponseData, HciManager &hciManager,
+                       const QLowEnergyAdvertisingData &scanResponseData,
+                       std::shared_ptr<HciManager> hciManager,
                        QObject *parent = nullptr);
     ~QLeAdvertiserBluez() override;
 
@@ -97,7 +98,7 @@ private:
     void handleCommandCompleted(quint16 opCode, quint8 status, const QByteArray &advertisingData);
     void handleError();
 
-    HciManager &m_hciManager;
+    std::shared_ptr<HciManager> m_hciManager;
 
     struct Command {
         Command() {}
diff --git a/src/bluetooth/qlowenergycontroller_bluez.cpp b/src/bluetooth/qlowenergycontroller_bluez.cpp
index af27d43e..bc790262 100644
--- a/src/bluetooth/qlowenergycontroller_bluez.cpp
+++ b/src/bluetooth/qlowenergycontroller_bluez.cpp
@@ -187,28 +187,30 @@ QLowEnergyControllerPrivateBluez::QLowEnergyControllerPrivateBluez()
 
 void QLowEnergyControllerPrivateBluez::init()
 {
-    hciManager = new HciManager(localAdapter, this);
+    // The HCI manager is shared between this class and the advertiser
+    hciManager = std::make_shared<HciManager>(localAdapter);
+
     if (!hciManager->isValid()){
         setError(QLowEnergyController::InvalidBluetoothAdapterError);
         return;
     }
 
     hciManager->monitorEvent(HciManager::HciEvent::EVT_ENCRYPT_CHANGE);
-    connect(hciManager, SIGNAL(encryptionChangedEvent(QBluetoothAddress,bool)),
+    connect(hciManager.get(), SIGNAL(encryptionChangedEvent(QBluetoothAddress,bool)),
             this, SLOT(encryptionChangedEvent(QBluetoothAddress,bool)));
     hciManager->monitorEvent(HciManager::HciEvent::EVT_LE_META_EVENT);
     hciManager->monitorAclPackets();
-    connect(hciManager, &HciManager::connectionComplete, [this](quint16 handle) {
+    connect(hciManager.get(), &HciManager::connectionComplete, [this](quint16 handle) {
         connectionHandle = handle;
         qCDebug(QT_BT_BLUEZ) << "received connection complete event, handle:" << handle;
     });
-    connect(hciManager, &HciManager::connectionUpdate,
+    connect(hciManager.get(), &HciManager::connectionUpdate,
             [this](quint16 handle, const QLowEnergyConnectionParameters &params) {
                 if (handle == connectionHandle)
                     emit q_ptr->connectionUpdated(params);
             }
     );
-    connect(hciManager, &HciManager::signatureResolvingKeyReceived,
+    connect(hciManager.get(), &HciManager::signatureResolvingKeyReceived,
             [this](quint16 handle, bool remoteKey, const quint128 &csrk) {
                 if (handle != connectionHandle)
                     return;
@@ -331,6 +333,7 @@ QLowEnergyControllerPrivateBluez::~QLowEnergyControllerPrivateBluez()
 {
     closeServerSocket();
     delete cmacCalculator;
+    cmacCalculator = nullptr;
 }
 
 class ServerSocket
@@ -389,7 +392,7 @@ void QLowEnergyControllerPrivateBluez::startAdvertising(const QLowEnergyAdvertis
 {
     qCDebug(QT_BT_BLUEZ) << "Starting to advertise";
     if (!advertiser) {
-        advertiser = new QLeAdvertiserBluez(params, advertisingData, scanResponseData, *hciManager,
+        advertiser = new QLeAdvertiserBluez(params, advertisingData, scanResponseData, hciManager,
                                             this);
         connect(advertiser, &QLeAdvertiser::errorOccurred, this,
                 &QLowEnergyControllerPrivateBluez::handleAdvertisingError);
diff --git a/src/bluetooth/qlowenergycontroller_bluez_p.h b/src/bluetooth/qlowenergycontroller_bluez_p.h
index 15c99eef..320349c6 100644
--- a/src/bluetooth/qlowenergycontroller_bluez_p.h
+++ b/src/bluetooth/qlowenergycontroller_bluez_p.h
@@ -166,7 +166,7 @@ private:
     bool encryptionChangePending;
     bool receivedMtuExchangeRequest = false;
 
-    HciManager *hciManager = nullptr;
+    std::shared_ptr<HciManager> hciManager;
     QLeAdvertiser *advertiser = nullptr;
     QSocketNotifier *serverSocketNotifier = nullptr;
     QTimer *requestTimer = nullptr;