Subject: CVE-2024-50021: ice: Fix improper handling of refcount in ice_dpll_init_rclk_pins()

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

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

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

ice: Fix improper handling of refcount in ice_dpll_init_rclk_pins()

This patch addresses a reference count handling issue in the
ice_dpll_init_rclk_pins() function. The function calls ice_dpll_get_pins(),
which increments the reference count of the relevant resources. However,
if the condition WARN_ON((!vsi || !vsi->netdev)) is met, the function
currently returns an error without properly releasing the resources
acquired by ice_dpll_get_pins(), leading to a reference count leak.

To resolve this, the check has been moved to the top of the function. This
ensures that the function verifies the state before any resources are
acquired, avoiding the need for additional resource management in the
error path.

This bug was identified by an experimental static analysis tool developed
by our team. The tool specializes in analyzing reference count operations
and detecting potential issues where resources are not properly managed.
In this case, the tool flagged the missing release operation as a
potential problem, which led to the development of this patch.

The Linux kernel CVE team has assigned CVE-2024-50021 to this issue.

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

	Issue introduced in 6.7 with commit d7999f5ea64b and fixed in 6.11.4 with commit aefecead9d08
	Issue introduced in 6.7 with commit d7999f5ea64b and fixed in 6.12-rc3 with commit ccca30a18e36

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-2024-50021
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/intel/ice/ice_dpll.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/aefecead9d08f4a35ab6f51ba2e408d2cef4e31d
	https://git.kernel.org/stable/c/ccca30a18e36a742e606d5bf0630e75be7711d0a