[plasma/plasma-desktop] kcms/gamecontroller: kcms/gamecontroller: Fix UB to use of uninitialized memory

Git commit 71b3e4dafaaab146d1054225bfaccf8115bebe2e by Sebastian Sauer.
Committed on 20/07/2026 at 04:29.
Pushed by meven into branch 'master'.

kcms/gamecontroller: Fix UB to use of uninitialized memory

In the else case sys_path was never initialized resulting
in random memory being passed into udev_device_new_from_syspath
what results in undefined behavior.

Based on a patch done by Adam Doda.

BUG: 522886

M  +3    -0    kcms/gamecontroller/udevmatcher.cpp

https://invent.kde.org/plasma/plasma-desktop/-/commit/71b3e4dafaaab146d1054225bfaccf8115bebe2e

diff --git a/kcms/gamecontroller/udevmatcher.cpp b/kcms/gamecontroller/udevmatcher.cpp
index 24febd0291..08d4606db3 100644
--- a/kcms/gamecontroller/udevmatcher.cpp
+++ b/kcms/gamecontroller/udevmatcher.cpp
@@ -31,6 +31,9 @@ std::string UDevMatcher::deviceToUdevId(const std::string &device_path)
     } else if (lastPart.starts_with("event")) {
         // input devpaths end with eventXY
         snprintf(sys_path, sizeof(sys_path), "/sys/class/input/%s", lastPart.c_str());
+    } else {
+        // Return empty if it doesn't match expected types
+        return devicePath;
     }
     std::unique_ptr<struct udev, decltype(&udev_unref)> udev(udev_new(), &udev_unref);
     if (!udev) {