CVE-2026-68319: pds_core: fix deadlock between reset thread and remove

From: Greg Kroah-Hartman <[email protected]>

Description
===========

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

pds_core: fix deadlock between reset thread and remove

pci_reset_function() acquires device_lock before performing the reset.
pdsc_remove() is called by the PCI core with device_lock already held.
If pdsc_pci_reset_thread() is running when pdsc_remove() is called,
destroy_workqueue() will block waiting for the work to complete, while
the work is blocked waiting for device_lock - deadlock.

Use pci_try_reset_function() which uses pci_dev_trylock() internally.
This acquires both the device lock and the PCI config access lock
without blocking - if either lock is contended, it returns -EAGAIN
immediately. This avoids the deadlock while also ensuring proper
config space access serialization during the reset.

The pci_dev_get/put calls are also removed as they were unnecessary -
the driver-owned workqueue is destroyed in pdsc_remove(), guaranteeing
the work completes before remove returns. The PCI core holds its
reference to pci_dev throughout the entire unbind sequence.

The Linux kernel CVE team has assigned CVE-2026-68319 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 6.9 with commit 81665adf25d28a00a986533f1d3a5df76b79cad9 and fixed in 6.12.101 with commit 90d9f3ef28843e6c35149324b8eefb427a7435c2
	Issue introduced in 6.9 with commit 81665adf25d28a00a986533f1d3a5df76b79cad9 and fixed in 6.18.42 with commit 19ef775c91c6bf4bd2b60f6616f4e28b621cdd6a
	Issue introduced in 6.9 with commit 81665adf25d28a00a986533f1d3a5df76b79cad9 and fixed in 7.1.6 with commit 54f905821f26d385fba407a920b51f0a752c76dc
	Issue introduced in 6.9 with commit 81665adf25d28a00a986533f1d3a5df76b79cad9 and fixed in 7.2-rc5 with commit ab0eec0ff0a421737a37f510ceab5c6ea59cd05a
	Issue introduced in 6.8.7 with commit 38407914d48273d7f8ab765b9243658afe1c3ab6

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-68319
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/net/ethernet/amd/pds_core/core.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/90d9f3ef28843e6c35149324b8eefb427a7435c2
	https://git.kernel.org/stable/c/19ef775c91c6bf4bd2b60f6616f4e28b621cdd6a
	https://git.kernel.org/stable/c/54f905821f26d385fba407a920b51f0a752c76dc
	https://git.kernel.org/stable/c/ab0eec0ff0a421737a37f510ceab5c6ea59cd05a