CVE-2026-23302: net: annotate data-races around sk->sk_{data_ready,write_space}

CVE-2026-23302: net: annotate data-races around sk->sk_{data_ready,write_space}

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

net: annotate data-races around sk->sk_{data_ready,write_space}

skmsg (and probably other layers) are changing these pointers
while other cpus might read them concurrently.

Add corresponding READ_ONCE()/WRITE_ONCE() annotations
for UDP, TCP and AF_UNIX.

The Linux kernel CVE team has assigned CVE-2026-23302 to this issue.


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

	Issue introduced in 4.20 with commit 604326b41a6fb9b4a78b6179335decee0365cd8c and fixed in 6.18.17 with commit f17c1c4acbe2bd702abce73a847a04a196fab2c5
	Issue introduced in 4.20 with commit 604326b41a6fb9b4a78b6179335decee0365cd8c and fixed in 6.19.7 with commit 27fccdbcbbfc4651b6f66756e6fa3f52e051ec23
	Issue introduced in 4.20 with commit 604326b41a6fb9b4a78b6179335decee0365cd8c and fixed in 7.0-rc3 with commit 2ef2b20cf4e04ac8a6ba68493f8780776ff84300

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-2026-23302
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:
	net/core/skmsg.c
	net/ipv4/tcp.c
	net/ipv4/tcp_bpf.c
	net/ipv4/tcp_input.c
	net/ipv4/tcp_minisocks.c
	net/ipv4/udp.c
	net/ipv4/udp_bpf.c
	net/unix/af_unix.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/f17c1c4acbe2bd702abce73a847a04a196fab2c5
	https://git.kernel.org/stable/c/27fccdbcbbfc4651b6f66756e6fa3f52e051ec23
	https://git.kernel.org/stable/c/2ef2b20cf4e04ac8a6ba68493f8780776ff84300