Check access to /proc/PID/root for FileChooser portal usage outside s…

…andbox
FedoraQt · Oct 19, 2020 · d5a01ea · d5a01ea
1 parent d87c71b
commit d5a01ea
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Showing 4 changed files with 55 additions and 26 deletions.
diff --git a/common/gnomehintssettings.cpp b/common/gnomehintssettings.cpp
@@ -31,10 +31,19 @@
 #include <QStyleFactory>
 #include <QSettings>
 #include <QStandardPaths>
+#include <QTimer>
 
 #include <QDBusArgument>
 #include <QDBusConnection>
 #include <QDBusMessage>
+#include <QDBusPendingCall>
+#include <QDBusPendingCallWatcher>
+#include <QDBusPendingReply>
+
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
 
 Q_LOGGING_CATEGORY(QGnomePlatform, "qt.qpa.qgnomeplatform")
 
@@ -78,6 +87,7 @@ void gtkMessageHandler(const gchar *log_domain,
 GnomeHintsSettings::GnomeHintsSettings()
     : QObject(0)
     , m_usePortal(checkUsePortalSupport())
+    , m_canUseFileChooserPortal(!m_usePortal)
     , m_gnomeDesktopSettings(g_settings_new("org.gnome.desktop.wm.preferences"))
     , m_settings(g_settings_new("org.gnome.desktop.interface"))
 {
@@ -140,6 +150,42 @@ GnomeHintsSettings::GnomeHintsSettings()
     loadStaticHints();
     loadTheme();
     loadTitlebar();
+
+    if (m_canUseFileChooserPortal) {
+        QTimer::singleShot(0, this, [this] () {
+            const QString filePath = QStringLiteral("/proc/%1/root").arg(QCoreApplication::applicationPid());
+            qWarning() << filePath;
+            struct stat info;
+            if (lstat(filePath.toStdString().c_str(), &info) == 0) {
+                if (!static_cast<int>(info.st_uid)) {
+                    m_canUseFileChooserPortal = false;
+                }
+            } else {
+                // Do not use FileChooser portal if we fail to get information about the file
+                m_canUseFileChooserPortal = false;
+            }
+        });
+
+        if (m_canUseFileChooserPortal) {
+            // Get information about portal version
+            QDBusMessage message = QDBusMessage::createMethodCall(QLatin1String("org.freedesktop.portal.Desktop"),
+                                                                  QLatin1String("/org/freedesktop/portal/desktop"),
+                                                                  QLatin1String("org.freedesktop.DBus.Properties"),
+                                                                  QLatin1String("Get"));
+            message << QLatin1String("org.freedesktop.portal.FileChooser") << QLatin1String("version");
+            QDBusPendingCall pendingCall = QDBusConnection::sessionBus().asyncCall(message);
+            QDBusPendingCallWatcher *watcher = new QDBusPendingCallWatcher(pendingCall);
+            QObject::connect(watcher, &QDBusPendingCallWatcher::finished, [this] (QDBusPendingCallWatcher *watcher) {
+                QDBusPendingReply<QVariant> reply = *watcher;
+                if (reply.isValid()) {
+                    uint fileChooserPortalVersion = reply.value().toUInt();
+                    if (fileChooserPortalVersion < 3) {
+                        m_canUseFileChooserPortal = false;
+                    }
+                }
+            });
+        }
+    }
 }
 
 GnomeHintsSettings::~GnomeHintsSettings()

diff --git a/common/gnomehintssettings.h b/common/gnomehintssettings.h
@@ -77,6 +77,11 @@ class GnomeHintsSettings : public QObject
         return palette;
     }
 
+    inline bool canUseFileChooserPortal() const
+    {
+        return m_canUseFileChooserPortal;
+    }
+
     inline bool gtkThemeDarkVariant() const
     {
         return m_gtkThemeDarkVariant;
@@ -167,6 +172,7 @@ private Q_SLOTS:
     void configureKvantum(const QString &theme) const;
 
     bool m_usePortal;
+    bool m_canUseFileChooserPortal = false;
     bool m_gtkThemeDarkVariant = false;
     TitlebarButtons m_titlebarButtons = TitlebarButton::CloseButton;
     TitlebarButtonsPlacement m_titlebarButtonPlacement = TitlebarButtonsPlacement::RightPlacement;

diff --git a/theme/qgnomeplatformtheme.cpp b/theme/qgnomeplatformtheme.cpp
@@ -27,12 +27,6 @@
 #include <QGuiApplication>
 #include <QStyleFactory>
 
-#include <QDBusConnection>
-#include <QDBusMessage>
-#include <QDBusPendingCall>
-#include <QDBusPendingCallWatcher>
-#include <QDBusPendingReply>
-
 #if !defined(QT_NO_DBUS) && !defined(QT_NO_SYSTEMTRAYICON)
 #include <private/qdbustrayicon_p.h>
 #endif
@@ -51,22 +45,6 @@ QGnomePlatformTheme::QGnomePlatformTheme()
      */
     g_type_ensure(PANGO_TYPE_FONT_FAMILY);
     g_type_ensure(PANGO_TYPE_FONT_FACE);
-
-
-    // Get information about portal version
-    QDBusMessage message = QDBusMessage::createMethodCall(QLatin1String("org.freedesktop.portal.Desktop"),
-                                                          QLatin1String("/org/freedesktop/portal/desktop"),
-                                                          QLatin1String("org.freedesktop.DBus.Properties"),
-                                                          QLatin1String("Get"));
-    message << QLatin1String("org.freedesktop.portal.FileChooser") << QLatin1String("version");
-    QDBusPendingCall pendingCall = QDBusConnection::sessionBus().asyncCall(message);
-    QDBusPendingCallWatcher *watcher = new QDBusPendingCallWatcher(pendingCall);
-    QObject::connect(watcher, &QDBusPendingCallWatcher::finished, [this] (QDBusPendingCallWatcher *watcher) {
-        QDBusPendingReply<QVariant> reply = *watcher;
-        if (reply.isValid()) {
-            fileChooserPortalVersion = reply.value().toUInt();
-        }
-    });
 }
 
 QGnomePlatformTheme::~QGnomePlatformTheme()
@@ -115,10 +93,10 @@ QPlatformDialogHelper *QGnomePlatformTheme::createPlatformDialogHelper(QPlatform
 {
     switch (type) {
     case QPlatformTheme::FileDialog: {
-        if (fileChooserPortalVersion < 3) {
-            return new QGtk3FileDialogHelper;
-        } else {
+        if (m_hints->canUseFileChooserPortal()) {
             return new QXdgDesktopPortalFileDialog;
+        } else {
+            return new QGtk3FileDialogHelper;
         }
     }
     case QPlatformTheme::FontDialog:

diff --git a/theme/qgnomeplatformtheme.h b/theme/qgnomeplatformtheme.h
@@ -46,7 +46,6 @@ class QGnomePlatformTheme : public QPlatformTheme
     void loadSettings();
 
     GnomeHintsSettings *m_hints;
-    uint fileChooserPortalVersion = 0;
 };
 
 #endif // QGNOME_PLATFORM_THEME_HH