In the Linux kernel, the following vulnerability has been resolved:
wifi: rt2x00: avoid full teardown before work setup in probe
rt2x00lib_probe_dev() uses the full rt2x00lib_remove_dev() teardown for
all probe failures. However, drv_data allocation and workqueue allocation
can fail before intf_work, autowakeup_work and sleep_work have been
initialized.
Do not enter the full remove path until the probe has reached the point
where those work items are set up. Return directly for drv_data allocation
failure, and use a small early cleanup path for workqueue allocation
failure.
This issue was found by our static analysis tool and then confirmed by
manual review of rt2x00lib_probe_dev() and rt2x00lib_remove_dev(). The
early probe exits should not call a common teardown path that assumes the
later work setup has already completed.
A QEMU PoC forced alloc_ordered_workqueue() to fail before the work
initializers are reached. The resulting fail path entered
rt2x00lib_remove_dev(), and DEBUG_OBJECTS reported invalid work drains with
rt2x00lib_probe_dev() and rt2x00lib_remove_dev() in the stack.
