In the Linux kernel, the following vulnerability has been resolved:
HID: mcp2221: stop device IO before hid_hw_stop
Quiesce device IO at the start of the devm cleanup callback
mcp2221_hid_unregister() so that incoming HID reports cannot race with
hardware teardown during probe failure or device removal, addressing a
potential use-after-free.
Guard the call to hid_device_io_stop() with io_started. On normal
removal hid_device_remove() has already cleared io_started before the
devres group is released, so an unconditional call would otherwise hit
the !io_started path and emit a spurious “io already stopped” warning
on every removal. The guard preserves the probe-failure balancing,
where io_started is still set after hid_device_io_start(), while
staying silent on the normal removal path.
