From 26ce4869a09e0061061c3f1e2cf2333a4ab1eb02 Mon Sep 17 00:00:00 2001
From: David Edmundson <kde@davidedmundson.co.uk>
Date: Mon, 6 Apr 2020 18:10:03 +0100
Subject: [PATCH] [xwl] Fix crash if same data is requested twice

Summary:
m_dataRequests is a list of transfers for a given selection.
It exists primarily as a ref counting mechanism that matches up
transfers with selections.

If the same data is requested twice we would insert two items into the
list with matching timestamps for the original selection. This then
confuses the callback handling.

BUG: 417936

Test Plan:
kwin_wayland + chromium
drag and drop a URL onto desktopview. kwin used to crash here
Now a context menu now appears and I can add a link

Reviewers: #kwin

Subscribers: kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D28630
---
 xwl/drag_x.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/xwl/drag_x.cpp b/xwl/drag_x.cpp
index f84bb136c2..10105d4123 100644
--- a/xwl/drag_x.cpp
+++ b/xwl/drag_x.cpp
@@ -69,13 +69,12 @@ XToWlDrag::XToWlDrag(X11Source *source)
         // we use this mechanism, because the finished call is not
         // reliable done by Wayland clients
         auto it = std::find_if(m_dataRequests.begin(), m_dataRequests.end(), [eventTime](const QPair<xcb_timestamp_t, bool> &req) {
-            return req.first == eventTime;
+            return req.first == eventTime && req.second == false;
         });
         if (it == m_dataRequests.end()) {
             // transfer finished for a different drag
             return;
         }
-        Q_ASSERT(!(*it).second);
         (*it).second = true;
         checkForFinished();
     });