CVE-2026-98786

drm/amd/display: guard dc_sink dereferences in MST mode validation

cve-program · severity unknownCVSS unknownCheck source for fixed versionsKEV status unknown

Original advisory

Historical advisory recorded 6 Nov 2026 19:02:40 UTC. Read the latest advisory.

cve-program · CVE-2026-98786

Published

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: guard dc_sink dereferences in MST mode validation dm_dp_mst_is_port_support_mode() reads aconnector->dc_sink->dsc_caps... for the DSC branch-throughput check, and get_conv_frl_bw()'s HDMI-PCON FRL-bandwidth path reads aconnector->dc_sink->edid_caps.max_frl_rate, both without a NULL check. dc_sink is cleared asynchronously on MST unplug, and both functions run from paths that the driver's own comments document as racing that teardown: the connector probe worker's ->mode_valid callback and a compositor's atomic check, neither of which holds the MST manager lock that the teardown path uses. The former does have an existing dsc_aux NULL check, but dsc_aux isn't reliably cleared in every path that clears dc_sink, so it doesn't cover this. Fail the port-support check and skip the FRL conversion path when the sink is already gone. (cherry picked from commit 7c3db8da4e039698ae198c870712428644e965c7)

Read the publisher's advisory

Affected versions, risk and source history

cve-program · CVE-2026-98786

Published

Linux

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "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/amdgpu_dm/amdgpu_dm_mst_types.c"
                    ],
                    "versions": [
                        {
                            "version": "f04d275d94e164d24516c32437c988a323018f63",
                            "lessThan": "5684a6c24c0d7c40ef2c4ccb3e4a64cffe76a791",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "f04d275d94e164d24516c32437c988a323018f63",
                            "lessThan": "daa0437fe5e451856aaf8fda602a9fc2105bbd54",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "f04d275d94e164d24516c32437c988a323018f63",
                            "lessThan": "217f64f348c90cba62164e7ff38e0ccf78a5ca09",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                }

Linux

Vendor product

Publisher's version information

Shown as published. These rules are not interpreted as NuGet package version ranges.

{
                    "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/amdgpu_dm/amdgpu_dm_mst_types.c"
                    ],
                    "versions": [
                        {
                            "version": "6.0",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.0",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.61",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.10",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }

Original source record · Cite this exact observation · Complete original publisher JSON