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.
References
- https://git.kernel.org/stable/c/3c0427d719bddb33caf18ff4ffb77cb47de7eb00
- https://git.kernel.org/stable/c/536fb3d739d75a03cb318c0c6fe799425cfea501
- https://git.kernel.org/stable/c/56994852d704535ea354a4627ca667b1b4fa0deb
- https://git.kernel.org/stable/c/59afe6148927395cf86f9429900e029a48b1d42b
- https://git.kernel.org/stable/c/66bd9b1a72de7c2f5141b02d796048aafaed8a49
- https://git.kernel.org/stable/c/816559409e340acaa5c9d868291dab30d8c80263
- https://git.kernel.org/stable/c/8b58d1f1356df6a7d2de3f55bb665b18b04ffda0
- https://git.kernel.org/stable/c/eb7474d0253bb2de4793e1d3ce833e8564bbe732