CVE-2026-43300: drm/panel: Fix a possible null-pointer dereference in jdi_panel_dsi_remove()

CVE-2026-43300: drm/panel: Fix a possible null-pointer dereference in jdi_panel_dsi_remove()

[Greg Kroah-Hartman]

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

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

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

drm/panel: Fix a possible null-pointer dereference in jdi_panel_dsi_remove()

In jdi_panel_dsi_remove(), jdi is explicitly checked, indicating that it
may be NULL:

  if (!jdi)
    mipi_dsi_detach(dsi);

However, when jdi is NULL, the function does not return and continues by
calling jdi_panel_disable():

  err = jdi_panel_disable(&jdi->base);

Inside jdi_panel_disable(), jdi is dereferenced unconditionally, which can
lead to a NULL-pointer dereference:

  struct jdi_panel *jdi = to_panel_jdi(panel);
  backlight_disable(jdi->backlight);

To prevent such a potential NULL-pointer dereference, return early from
jdi_panel_dsi_remove() when jdi is NULL.

The Linux kernel CVE team has assigned CVE-2026-43300 to this issue.


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

	Fixed in 6.12.75 with commit ec2f37bbb733cdd7ed7d04171fca728a532414d5
	Fixed in 6.18.16 with commit 2f5427d8726b22b807beec248d7d6bf88e291e0b
	Fixed in 6.19.6 with commit 83ce0085fabf757b039322928188ad78e962d609
	Fixed in 7.0 with commit 95eed73b871111123a8b1d31cb1fce7e902e49ea

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-2026-43300
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/gpu/drm/panel/panel-jdi-lpm102a188a.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/ec2f37bbb733cdd7ed7d04171fca728a532414d5
	https://git.kernel.org/stable/c/2f5427d8726b22b807beec248d7d6bf88e291e0b
	https://git.kernel.org/stable/c/83ce0085fabf757b039322928188ad78e962d609
	https://git.kernel.org/stable/c/95eed73b871111123a8b1d31cb1fce7e902e49ea