CVE-2026-74548: forcedeth: fix UAF of txrx_stats in nv_remove

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

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

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

forcedeth: fix UAF of txrx_stats in nv_remove

nv_remove() frees the per-CPU txrx_stats before unregister_netdev().
Until unregister completes, ndo_get_stats64, the NAPI/xmit data path,
and nv_close()/drain may still access txrx_stats, leading to a
use-after-free.

Free the stats only after unregister_netdev().

The Linux kernel CVE team has assigned CVE-2026-74548 to this issue.


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

	Issue introduced in 5.3 with commit f4b633b911fd3b4cbe1dc065e8fb064078d0889d and fixed in 6.6.151 with commit cf2dcde2284562ff87830ca0b7fa2b06e95aef1e
	Issue introduced in 5.3 with commit f4b633b911fd3b4cbe1dc065e8fb064078d0889d and fixed in 6.12.103 with commit c9d24a205fd508b9999fcab6aca4c590490a12cf
	Issue introduced in 5.3 with commit f4b633b911fd3b4cbe1dc065e8fb064078d0889d and fixed in 6.18.44 with commit ae20a8a4de06a289d40b0a0633d8d573f1fcb049
	Issue introduced in 5.3 with commit f4b633b911fd3b4cbe1dc065e8fb064078d0889d and fixed in 7.1.8 with commit 201e05aa531eba0dfe2ee05b4e178f6ffa12c8b1
	Issue introduced in 5.3 with commit f4b633b911fd3b4cbe1dc065e8fb064078d0889d and fixed in 7.2-rc6 with commit 22666ba1420164753d7b0f5a841986b25ace5435

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-2026-74548
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/nvidia/forcedeth.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/cf2dcde2284562ff87830ca0b7fa2b06e95aef1e
	https://git.kernel.org/stable/c/c9d24a205fd508b9999fcab6aca4c590490a12cf
	https://git.kernel.org/stable/c/ae20a8a4de06a289d40b0a0633d8d573f1fcb049
	https://git.kernel.org/stable/c/201e05aa531eba0dfe2ee05b4e178f6ffa12c8b1
	https://git.kernel.org/stable/c/22666ba1420164753d7b0f5a841986b25ace5435