[WPE][GTK] BubblewrapLauncher leaks D-Bus proxy sockets

https://bugs.webkit.org/show_bug.cgi?id=201771

Reviewed by Michael Catanzaro.

xdg-dbus-proxy removes the socket when the sync fd is closed by the application. In most of the cases the
xdg-dbus-proxy process is killed before the sync fd is closed and the socket file is leaked. We should
explicitly close the sync fd.

* UIProcess/Launcher/glib/XDGDBusProxy.cpp:
(WebKit::XDGDBusProxy::XDGDBusProxy): Save the sync fd.
(WebKit::XDGDBusProxy::~XDGDBusProxy): Close the sync fd is needed.
(WebKit::XDGDBusProxy::launch const): Return the sync fd.
* UIProcess/Launcher/glib/XDGDBusProxy.h:


Canonical link: https://commits.webkit.org/247121@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@289608 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebKit/ChangeLog

@@ -1,3 +1,20 @@
+2022-02-11  Carlos Garcia Campos  <cgarcia@igalia.com>
+
+        [WPE][GTK] BubblewrapLauncher leaks D-Bus proxy sockets
+        https://bugs.webkit.org/show_bug.cgi?id=201771
+
+        Reviewed by Michael Catanzaro.
+
+        xdg-dbus-proxy removes the socket when the sync fd is closed by the application. In most of the cases the
+        xdg-dbus-proxy process is killed before the sync fd is closed and the socket file is leaked. We should
+        explicitly close the sync fd.
+
+        * UIProcess/Launcher/glib/XDGDBusProxy.cpp:
+        (WebKit::XDGDBusProxy::XDGDBusProxy): Save the sync fd.
+        (WebKit::XDGDBusProxy::~XDGDBusProxy): Close the sync fd is needed.
+        (WebKit::XDGDBusProxy::launch const): Return the sync fd.
+        * UIProcess/Launcher/glib/XDGDBusProxy.h:
+
 2022-02-10  Simon Fraser  <simon.fraser@apple.com>
 
         Separate out setVolatile() from setNonVolatile() on IOSurface-backed buffers

Source/WebKit/UIProcess/Launcher/glib/XDGDBusProxy.cpp

@@ -74,7 +74,13 @@ XDGDBusProxy::XDGDBusProxy(Type type, bool allowPortals)
         m_path = CString(path, pathEnd - path);
     }
 
-    launch(allowPortals);
+    m_syncFD = launch(allowPortals);
+}
+
+XDGDBusProxy::~XDGDBusProxy()
+{
+    if (m_syncFD != -1)
+        close(m_syncFD);
 }
 
 CString XDGDBusProxy::makeProxy() const
@@ -106,7 +112,7 @@ CString XDGDBusProxy::makeProxy() const
     return proxySocketTemplate.get();
 }
 
-void XDGDBusProxy::launch(bool allowPortals) const
+int XDGDBusProxy::launch(bool allowPortals) const
 {
     int syncFds[2];
     if (pipe(syncFds) == -1)
@@ -203,6 +209,8 @@ void XDGDBusProxy::launch(bool allowPortals) const
     char out;
     if (read(syncFds[0], &out, 1) != 1)
         g_error("Failed to fully launch dbus-proxy: %s", g_strerror(errno));
+
+    return syncFds[0];
 }
 
 } // namespace WebKit

Source/WebKit/UIProcess/Launcher/glib/XDGDBusProxy.h

@@ -37,18 +37,20 @@ class XDGDBusProxy {
 public:
     enum class Type { SessionBus, AccessibilityBus };
     XDGDBusProxy(Type, bool = false);
+    ~XDGDBusProxy();
 
     const CString& proxyPath() const { return m_proxyPath; }
     const CString& path() const { return m_path; }
 
 private:
     CString makeProxy() const;
-    void launch(bool) const;
+    int launch(bool) const;
 
     Type m_type;
     CString m_dbusAddress;
     CString m_proxyPath;
     CString m_path;
+    int m_syncFD { -1 };
 };
 
 } // namespace WebKit