drm/amd/display: Do not skip unrelated mode changes in DSC validation
Summary
| CVE | CVE-2026-31488 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-22 14:16:46 UTC |
| Updated | 2026-07-10 12:16:38 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Do not skip unrelated mode changes in DSC validation Starting with commit 17ce8a6907f7 ("drm/amd/display: Add dsc pre-validation in atomic check"), amdgpu resets the CRTC state mode_changed flag to false when recomputing the DSC configuration results in no timing change for a particular stream. However, this is incorrect in scenarios where a change in MST/DSC configuration happens in the same KMS commit as another (unrelated) mode change. For example, the integrated panel of a laptop may be configured differently (e.g., HDR enabled/disabled) depending on whether external screens are attached. In this case, plugging in external DP-MST screens may result in the mode_changed flag being dropped incorrectly for the integrated panel if its DSC configuration did not change during precomputation in pre_validate_dsc(). At this point, however, dm_update_crtc_state() has already created new streams for CRTCs with DSC-independent mode changes. In turn, amdgpu_dm_commit_streams() will never release the old stream, resulting in a memory leak. amdgpu_dm_atomic_commit_tail() will never acquire a reference to the new stream either, which manifests as a use-after-free when the stream gets disabled later on: BUG: KASAN: use-after-free in dc_stream_release+0x25/0x90 [amdgpu] Write of size 4 at addr ffff88813d836524 by task kworker/9:9/29977 Workqueue: events drm_mode_rmfb_work_fn Call Trace: <TASK> dump_stack_lvl+0x6e/0xa0 print_address_description.constprop.0+0x88/0x320 ? dc_stream_release+0x25/0x90 [amdgpu] print_report+0xfc/0x1ff ? srso_alias_return_thunk+0x5/0xfbef5 ? __virt_addr_valid+0x225/0x4e0 ? dc_stream_release+0x25/0x90 [amdgpu] kasan_report+0xe1/0x180 ? dc_stream_release+0x25/0x90 [amdgpu] kasan_check_range+0x125/0x200 dc_stream_release+0x25/0x90 [amdgpu] dc_state_destruct+0x14d/0x5c0 [amdgpu] dc_state_release.part.0+0x4e/0x130 [amdgpu] dm_atomic_destroy_state+0x3f/0x70 [amdgpu] drm_atomic_state_default_clear+0x8ee/0xf30 ? drm_mode_object_put.part.0+0xb1/0x130 __drm_atomic_state_free+0x15c/0x2d0 atomic_remove_fb+0x67e/0x980 Since there is no reliable way of figuring out whether a CRTC has unrelated mode changes pending at the time of DSC validation, remember the value of the mode_changed flag from before the point where a CRTC was marked as potentially affected by a change in DSC configuration. Reset the mode_changed flag to this earlier value instead in pre_validate_dsc(). (cherry picked from commit cc7c7121ae082b7b82891baa7280f1ff2608f22b) |
Risk And Classification
Primary CVSS: v3.1 7.8 HIGH from ADP
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.000180000 probability, percentile 0.046080000 (date 2026-04-27)
Problem Types: CWE-416 | CWE-1288 | CWE-1288 Improper Validation of Consistency within Input
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | CVSS | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | DECLARED | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 17ce8a6907f77b7ac97ddaa071d8a1f6e06ce85b da1d0ed31e9802fd99384f43cc63678a5a11cb41 git | Not specified |
| CNA | Linux | Linux | affected 17ce8a6907f77b7ac97ddaa071d8a1f6e06ce85b 21159d8b335a6b9f44cbb506733013a902ae2da4 git | Not specified |
| CNA | Linux | Linux | affected 17ce8a6907f77b7ac97ddaa071d8a1f6e06ce85b 10862e344b4d6434642a48c87d765813fc0b0ba7 git | Not specified |
| CNA | Linux | Linux | affected 17ce8a6907f77b7ac97ddaa071d8a1f6e06ce85b 8a5edc97fd9c6415ff2eff872748439a97e3c3d8 git | Not specified |
| CNA | Linux | Linux | affected 17ce8a6907f77b7ac97ddaa071d8a1f6e06ce85b 111208b5b7ebcdadb3f922cc52d8425f0fa91b33 git | Not specified |
| CNA | Linux | Linux | affected 17ce8a6907f77b7ac97ddaa071d8a1f6e06ce85b aed3d041ab061ec8a64f50a3edda0f4db7280025 git | Not specified |
| CNA | Linux | Linux | affected 5.18 | Not specified |
| CNA | Linux | Linux | unaffected 5.18 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.175 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.140 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.80 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.21 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.11 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux AppStream V. 9 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux BaseOS V. 8 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux BaseOS V. 9 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux CRB V. 8 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux CodeReady Linux Builder V. 9 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux NFV V. 8 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux Real Time For NFV V. 9 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux RT V. 8 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux Real Time V. 9 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 10 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 6 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 7 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | |
| git.kernel.org/stable/c/da1d0ed31e9802fd99384f43cc63678a5a11cb41 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/aed3d041ab061ec8a64f50a3edda0f4db7280025 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/10862e344b4d6434642a48c87d765813fc0b0ba7 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/111208b5b7ebcdadb3f922cc52d8425f0fa91b33 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| access.redhat.com/errata/RHSA-2026:27354 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31488.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:27353 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:30848 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-31488 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| git.kernel.org/stable/c/8a5edc97fd9c6415ff2eff872748439a97e3c3d8 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/21159d8b335a6b9f44cbb506733013a902ae2da4 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| ADP | 2026-04-22T00:00:00.000Z | Reported to Red Hat. |
| ADP | 2026-04-22T00:00:00.000Z | Made public. |
Solutions
ADP: RHSA-2026:30848: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9)
ADP: RHSA-2026:27353: Red Hat Enterprise Linux BaseOS (v. 8), Red Hat Enterprise Linux CRB (v. 8)
ADP: RHSA-2026:27354: Red Hat Enterprise Linux NFV (v. 8), Red Hat Enterprise Linux RT (v. 8)
Workarounds
ADP: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.