Subject: CVE-2024-36002: dpll: fix dpll_pin_on_pin_register() for multiple parent pins

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

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

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

dpll: fix dpll_pin_on_pin_register() for multiple parent pins

In scenario where pin is registered with multiple parent pins via
dpll_pin_on_pin_register(..), all belonging to the same dpll device.
A second call to dpll_pin_on_pin_unregister(..) would cause a call trace,
as it tries to use already released registration resources (due to fix
introduced in b446631f355e). In this scenario pin was registered twice,
so resources are not yet expected to be release until each registered
pin/pin pair is unregistered.

Currently, the following crash/call trace is produced when ice driver is
removed on the system with installed E810T NIC which includes dpll device:

WARNING: CPU: 51 PID: 9155 at drivers/dpll/dpll_core.c:809 dpll_pin_ops+0x20/0x30
RIP: 0010:dpll_pin_ops+0x20/0x30
Call Trace:
 ? __warn+0x7f/0x130
 ? dpll_pin_ops+0x20/0x30
 dpll_msg_add_pin_freq+0x37/0x1d0
 dpll_cmd_pin_get_one+0x1c0/0x400
 ? __nlmsg_put+0x63/0x80
 dpll_pin_event_send+0x93/0x140
 dpll_pin_on_pin_unregister+0x3f/0x100
 ice_dpll_deinit_pins+0xa1/0x230 [ice]
 ice_remove+0xf1/0x210 [ice]

Fix by adding a parent pointer as a cookie when creating a registration,
also when searching for it. For the regular pins pass NULL, this allows to
create separated registration for each parent the pin is registered with.

The Linux kernel CVE team has assigned CVE-2024-36002 to this issue.

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

	Issue introduced in 6.8.2 with commit b27e32e9367d and fixed in 6.8.9 with commit f3e1cf62d182
	Issue introduced in 6.7.11 with commit 769324eb3514

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-2024-36002
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/dpll/dpll_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/f3e1cf62d18220a3aa97e084e7a3552debece9fc
	https://git.kernel.org/stable/c/38d7b94e81d068b8d8c8392f421cfd2c3bbfd1a6