Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: virtio_balloon: quiesce balloon work before device shutdown Commit 8bd2fa086a04 ("virtio: break and reset virtio devices on device_shutdown()") added a generic virtio bus .shutdown handler that breaks and resets every virtio device during device_shutdown(), i.e. on reboot and kexec. virtio_balloon provides no .shutdown of its own, so that generic path runs while the balloon's asynchronous work is still armed. Once the device has been broken, virtqueue_add_inbuf() in virtballoon_free_page_report() returns -EIO and trips its WARN_ON_ONCE(). On a kernel booted with panic_on_warn that turns an ordinary reboot, for example a kexec based upgrade, into a fatal panic in the middle of device_shutdown(), so the machine never reaches the new kernel. Relaxing that single WARN_ON_ONCE() would only hide the symptom: the inflate/deflate and OOM paths do not warn, they call wait_event(vb->acked, ...) and would instead block forever on a broken queue that can no longer complete. The device has to be quiesced, not just kept quiet. Add a .shutdown handler that quiesces the balloon via the shared virtballoon_quiesce() helper while the device is still alive, and only then breaks and resets it via virtio_device_shutdown(). Unlike virtballoon_remove() the balloon workqueue is not destroyed, as shutdown does not free the device and cancel_work_sync() together with stop_update already prevent any further work from being queued.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 8bd2fa086a04886798b505f28db4002525895203 before 6dd28e32f4d81a0d57c732b9900de24184e60a7d; affected 8bd2fa086a04886798b505f28db4002525895203 before bdef50a8226fc04899ef6815dd08a002247d47d5; affected 8bd2fa086a04886798b505f28db4002525895203 before 7e17eef04600c399c7e0f5ce765da5cf9d40d8e1; affected acdfe206be6c70ec55dc8bfdb1a22036d10fae26; affected 1eaa83fd94ed5e40d43139025f5acb7bcfed3b5f; affected aee42f3d57bfa37b2716df4584edeecf63b9df4c; affected 6.6.160 before 6.7; affected 6.12.114 before 6.13; affected 6.14.9 before 6.15 |
| Linux / Linux | affected 6.15; unaffected 0 before 6.15; unaffected 6.18.52 through 6.18.*; unaffected 7.2.6 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.