Subject: CVE-2024-35790: usb: typec: altmodes/displayport: create sysfs nodes as driver's default device attribute group

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

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

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

usb: typec: altmodes/displayport: create sysfs nodes as driver's default device attribute group

The DisplayPort driver's sysfs nodes may be present to the userspace before
typec_altmode_set_drvdata() completes in dp_altmode_probe. This means that
a sysfs read can trigger a NULL pointer error by deferencing dp->hpd in
hpd_show or dp->lock in pin_assignment_show, as dev_get_drvdata() returns
NULL in those cases.

Remove manual sysfs node creation in favor of adding attribute group as
default for devices bound to the driver. The ATTRIBUTE_GROUPS() macro is
not used here otherwise the path to the sysfs nodes is no longer compliant
with the ABI.

The Linux kernel CVE team has assigned CVE-2024-35790 to this issue.

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

	Issue introduced in 4.19 with commit 0e3bb7d6894d and fixed in 6.6.24 with commit 4a22aeac24d0
	Issue introduced in 4.19 with commit 0e3bb7d6894d and fixed in 6.7.12 with commit 0ad011776c05
	Issue introduced in 4.19 with commit 0e3bb7d6894d and fixed in 6.8 with commit 165376f6b23e

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-2024-35790
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/usb/typec/altmodes/displayport.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/4a22aeac24d0d5f26ba741408e8b5a4be6dc5dc0
	https://git.kernel.org/stable/c/0ad011776c057ce881b7fd6d8c79ecd459c087e9
	https://git.kernel.org/stable/c/165376f6b23e9a779850e750fb2eb06622e5a531