// For flags

CVE-2021-47108

drm/mediatek: hdmi: Perform NULL pointer check for mtk_hdmi_conf

Severity Score

"-"
*CVSS v-

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

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

drm/mediatek: hdmi: Perform NULL pointer check for mtk_hdmi_conf

In commit 41ca9caaae0b
("drm/mediatek: hdmi: Add check for CEA modes only") a check
for CEA modes was added to function mtk_hdmi_bridge_mode_valid()
in order to address possible issues on MT8167;
moreover, with commit c91026a938c2
("drm/mediatek: hdmi: Add optional limit on maximal HDMI mode clock")
another similar check was introduced.

Unfortunately though, at the time of writing, MT8173 does not provide
any mtk_hdmi_conf structure and this is crashing the kernel with NULL
pointer upon entering mtk_hdmi_bridge_mode_valid(), which happens as
soon as a HDMI cable gets plugged in.

To fix this regression, add a NULL pointer check for hdmi->conf in the
said function, restoring HDMI functionality and avoiding NULL pointer
kernel panics.

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: drm/mediatek: hdmi: realice una verificación de puntero NULL para mtk_hdmi_conf En el commit 41ca9caaae0b ("drm/mediatek: hdmi: agregue verificación solo para modos CEA") se agregó una verificación para los modos CEA funcionar mtk_hdmi_bridge_mode_valid() para solucionar posibles problemas en MT8167; Además, con el commit c91026a938c2 ("drm/mediatek: hdmi: Agregar límite opcional en el reloj máximo en modo HDMI") se introdujo otra verificación similar. Desafortunadamente, al momento de escribir este artículo, MT8173 no proporciona ninguna estructura mtk_hdmi_conf y esto bloquea el kernel con un puntero NULL al ingresar a mtk_hdmi_bridge_mode_valid(), lo que sucede tan pronto como se conecta un cable HDMI. Para solucionar esta regresión, agregue un El puntero NULL comprueba hdmi->conf en dicha función, restaurando la funcionalidad HDMI y evitando pánicos del kernel del puntero NULL.

*Credits: N/A
CVSS Scores
Attack Vector
-
Attack Complexity
-
Privileges Required
-
User Interaction
-
Scope
-
Confidentiality
-
Integrity
-
Availability
-
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-03-04 CVE Reserved
  • 2024-03-04 CVE Published
  • 2024-03-05 EPSS Updated
  • 2024-08-04 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.14 < 5.15.12
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.14 < 5.15.12"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.14 < 5.16
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.14 < 5.16"
en
Affected