CVE-2026-89624

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> HID: universal-pidff: stop the device when force-feedback init fails<br /> <br /> universal_pidff_probe() starts the device with hid_hw_start() and then, if<br /> force-feedback initialisation fails, returns the error through a label that<br /> only does "return error". The device is left started.<br /> <br /> The HID core does not unwind on the driver&amp;#39;s behalf. __hid_device_probe()<br /> releases the devres group, closes the report and clears hdev-&gt;driver:<br /> <br /> if (ret) {<br /> devres_release_group(&amp;hdev-&gt;dev, hdev-&gt;devres_group_id);<br /> hid_close_report(hdev);<br /> hdev-&gt;driver = NULL;<br /> }<br /> <br /> The hidraw character device that hid_hw_start() registered through<br /> hid_connect() is allocated with kzalloc() and added with cdev_device_add(),<br /> so it is not devres-managed and survives that. With hdev-&gt;driver NULL,<br /> hid_device_remove() skips hid_hw_stop() as well, because it only unwinds<br /> while a driver is still attached. The registration therefore outlives the<br /> device on both paths.<br /> <br /> Opening the surviving /dev/hidrawX writes into freed memory. KASAN reports<br /> a use-after-free write from hidraw_open() -&gt; hid_hw_open() -&gt; the<br /> transport&amp;#39;s open callback, which takes a spinlock inside the freed object.<br /> A descriptor that carries a PID usage page and no input reports is enough:<br /> hidraw claims the device so hid_hw_start() succeeds, while hid-&gt;inputs<br /> stays empty so force-feedback init fails. The other failure returns in<br /> hid_pidff_init_with_quirks() - no output reports, an allocation failure,<br /> pidff_init_fields(), pidff_check_autocenter(), an unusable effect count,<br /> input_ff_create() - all reach the same label.<br /> <br /> Stop the device on that path. hid-dr.c and hid-emsff.c, which start the<br /> device with the same HID_CONNECT_DEFAULT &amp; ~HID_CONNECT_FF mask, already do<br /> this. The two earlier gotos must keep returning without hid_hw_stop(),<br /> since neither has a started device, so give the path that fails after the<br /> start its own label.<br /> <br /> Discovered by XBOW, triaged by Baul Lee