Description

In the Linux kernel, the following vulnerability has been resolved:

PCI: switchtec: Fix stdev_release() crash after surprise hot remove

A PCI device hot removal may occur while stdev->cdev is held open. The call
to stdev_release() then happens during close or exit, at a point way past
switchtec_pci_remove(). Otherwise the last ref would vanish with the
trailing put_device(), just before return.

At that later point in time, the devm cleanup has already removed the
stdev->mmio_mrpc mapping. Also, the stdev->pdev reference was not a counted
one. Therefore, in DMA mode, the iowrite32() in stdev_release() will cause
a fatal page fault, and the subsequent dma_free_coherent(), if reached,
would pass a stale &stdev->pdev->dev pointer.

Fix by moving MRPC DMA shutdown into switchtec_pci_remove(), after
stdev_kill(). Counting the stdev->pdev ref is now optional, but may prevent
future accidents.

Reproducible via the script at
https://lore.kernel.org/r/[email protected]

Classification

CVE ID: CVE-2023-52617

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 12.41% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

https://git.kernel.org/stable/c/d8c293549946ee5078ed0ab77793cec365559355
https://git.kernel.org/stable/c/4a5d0528cf19dbf060313dffbe047bc11c90c24c
https://git.kernel.org/stable/c/ff1c7e2fb9e9c3f53715fbe04d3ac47b80be7eb8
https://git.kernel.org/stable/c/1d83c85922647758c1f1e4806a4c5c3cf591a20a
https://git.kernel.org/stable/c/0233b836312e39a3c763fb53512b3fa455b473b3
https://git.kernel.org/stable/c/e129c7fa7070fbce57feb0bfc5eaa65eef44b693
https://git.kernel.org/stable/c/df25461119d987b8c81d232cfe4411e91dcabe66

Timeline