CVE-2026-74263: net: wwan: t7xx: check skb_clone in control TX

CVE-2026-74263: net: wwan: t7xx: check skb_clone in control TX

[Greg Kroah-Hartman]

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

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

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

net: wwan: t7xx: check skb_clone in control TX

t7xx_port_ctrl_tx() clones each skb fragment before passing it to the
port transmit path. The clone is used immediately to set cloned->len, so
an skb_clone() failure results in a NULL pointer dereference.

Check the clone before using it. If previous fragments were already
queued, preserve the driver's existing partial-write behavior by
returning the number of bytes submitted so far.

The Linux kernel CVE team has assigned CVE-2026-74263 to this issue.


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

	Issue introduced in 6.4 with commit 36bd28c1cb0dbf48645cfe43159907fb3253b33a and fixed in 6.6.145 with commit 7edd4db82f9429591de10be4c904c817f12ba029
	Issue introduced in 6.4 with commit 36bd28c1cb0dbf48645cfe43159907fb3253b33a and fixed in 6.12.97 with commit 112490467586146d323cb7230b1d72137e36900c
	Issue introduced in 6.4 with commit 36bd28c1cb0dbf48645cfe43159907fb3253b33a and fixed in 6.18.40 with commit f7aebaee2961bfcb86f282202d3dbd9b69db1a7c
	Issue introduced in 6.4 with commit 36bd28c1cb0dbf48645cfe43159907fb3253b33a and fixed in 7.1.5 with commit 4c1b25d85f4c9a0f85f3f8c39988ad266a3f3095
	Issue introduced in 6.4 with commit 36bd28c1cb0dbf48645cfe43159907fb3253b33a and fixed in 7.2-rc1 with commit 05f789fa90d95d5771230e78453cedff2486039d

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-2026-74263
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/wwan/t7xx/t7xx_port_wwan.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/7edd4db82f9429591de10be4c904c817f12ba029
	https://git.kernel.org/stable/c/112490467586146d323cb7230b1d72137e36900c
	https://git.kernel.org/stable/c/f7aebaee2961bfcb86f282202d3dbd9b69db1a7c
	https://git.kernel.org/stable/c/4c1b25d85f4c9a0f85f3f8c39988ad266a3f3095
	https://git.kernel.org/stable/c/05f789fa90d95d5771230e78453cedff2486039d