CVE-2021-47046 drm/amd/display: Fix off by one in hdmi_14_process_transaction()

2024-02-2808:13:50

Linux

github.com

linux kernel

drm/amd/display

hdcp_i2c_offsets

read overflow

vulnerability fix

6.9 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

15.7%

JSON

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

drm/amd/display: Fix off by one in hdmi_14_process_transaction()

The hdcp_i2c_offsets[] array did not have an entry for
HDCP_MESSAGE_ID_WRITE_CONTENT_STREAM_TYPE so it led to an off by one
read overflow. I added an entry and copied the 0x0 value for the offset
from similar code in drivers/gpu/drm/amd/display/modules/hdcp/hdcp_ddc.c.

I also declared several of these arrays as having HDCP_MESSAGE_ID_MAX
entries. This doesn’t change the code, but it’s just a belt and
suspenders approach to try future proof the code.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/gpu/drm/amd/display/dc/hdcp/hdcp_msg.c"
    ],
    "versions": [
      {
        "version": "4c283fdac08a",
        "lessThan": "403c4528e588",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4c283fdac08a",
        "lessThan": "6a58310d5d1e",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4c283fdac08a",
        "lessThan": "080bd41d6478",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4c283fdac08a",
        "lessThan": "8e6fafd5a22e",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/gpu/drm/amd/display/dc/hdcp/hdcp_msg.c"
    ],
    "versions": [
      {
        "version": "5.5",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.5",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.37",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.11.21",
        "lessThanOrEqual": "5.11.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.12.4",
        "lessThanOrEqual": "5.12.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.13",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]