From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-98898][LOW] drm/amd/pm/si: Don't schedule thermal work when queue isn't initialized [ Upstream Date: Mon, 26 Oct 2026 20:46:00 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-98898 X-AL-KERNEL-Priority: LOW X-AL-KERNEL-Severity: LOW X-AL-KERNEL-Base-Severity: LOW X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 0 X-AL-KERNEL-ActionableScore-Lower: unknown X-AL-KERNEL-Commit: 2c08ae91df3cf11d517dc1273195f7b1df2a0ddb List-Id: CVE: CVE-2026-98898 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: drm/amd/pm/si: Don't schedule thermal work when queue isn't initialized [ Upstream Commit: 2c08ae91df3cf11d517dc1273195f7b1df2a0ddb Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2c08ae91df3cf11d517dc1273195f7b1df2a0ddb Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98898 Analysis date: Mon, 26 Oct 2026 20:46:00 -0400 ActionableScore: 0 ActionableScore lower bound: unknown Actionable bucket: Ordinary Moderate Manual review required: NO Summary: An AMD SI thermal interrupt can schedule an uninitialized work item when DPM is disabled, plausibly causing a warning, driver failure, or kernel crash without a shown corruption primitive. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98898 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98898 The original announcement does not normally provide a security severity estimate, CVSS assessment, or enough information to determine whether the reported kernel bug represents a practically relevant security issue. This report was generated by AL-KERNEL, an AI-assisted Linux kernel vulnerability analysis system developed by Alexander Larkin. It combines an autonomous classifier with LLM-assisted technical analysis and a separate ActionableScore mechanism. The purpose of this report is to prioritize Linux kernel CVEs before manual review, identify cases that require prompt investigation, and support automatic closure of issues that are unlikely to have meaningful security impact. Published priority for this report: LOW Manual review required: NO A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-98898 LOW https://www.kernelcve.org/list/?q=CVE-2026-98898 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT LOW AEGIS_AS=0 LEGACY=LOW RESULT=SAME (final reconciliation agrees; DECISION: both LOW) Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H';CWE-665;CWE-754;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.7';DESCR 'With amdgpu DPM disabled, the thermal work item is not initialized, but a thermal interrupt could still make si_dpm_process_interrupt pass it to schedule_work. This is an invalid workqueue object state that may cause a warning, driver failure, or kernel crash, but the patch provides no evidence of UAF, OOB access, information disclosure, or a controlled write. For the CVSS the PR:L value reflects that practical attacker influence would require a local user or process able to generate GPU workload, while reliable control of the thermal event is not established. Attack complexity is high because the system must use affected AMD SI hardware, boot with amdgpu.dpm disabled, and encounter a qualifying interrupt. Automated impact decision path. The original SimpleNet classifier selected LOW. The primary LLM estimated paranoid CVSS 4.7 and the production ActionableScore returned 0 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. No severity changing production threshold or specialist override was recorded. The legacy KP specialist has no review artifact for this run. The legacy FD or DH downgrade specialist has no review artifact for this run. The independent weaker Aegis shadow evaluated CVSS 0.0 and ActionableScore 0 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was LOW. The shadow agreed with the final production impact and aggregation did not change that impact. The final reported impact is LOW.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 0) MAYBE HARDWARE - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=0 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=NO AutoDowngradeAllowed=YES RequiresHostUID0=UNKNOWN AuthorizationDecisionBypass=NO ProtectedResourceImpact=NONE B4PendingReview=NO B4PendingConfirmed=NO 1. ActionableScore * Raw base score: 0. * Conservative score: 0; no floor or cap applied. * Raw paranoid score: 0. * Paranoid score: 0; no floor or cap applied. * Final recommended bucket: **Ordinary Moderate**:: 2. Signal breakdown * +1 Reliable kernel crash / strong DoS: `schedule_work()` can receive an uninitialized thermal work item when `amdgpu_dpm=0`; a warning, driver failure, or kernel fault is plausible. * -1 Rare and difficult-to-reach configuration: the path requires affected AMD SI hardware, DPM disabled through a boot/module parameter, and a qualifying thermal interrupt. An attacker cannot ordinarily instantiate these prerequisites. * No UAF, OOB access, heap overwrite, initialized-object corruption, disclosure, authorization bypass, or controlled write is shown. * No extra availability point: any warning or crash is the same immediate invalid-work-item consequence. * No race penalty: difficult interrupt control is already represented by the configuration/reachability limitation. * NEW52/B5-R does not apply: there is no retry-accumulated index or confirmed OOB write. * NEW53/B3-PENDING does not apply: no shared-backing write exists. * NEW54/B4-PENDING does not apply: the added condition is an initialization-state guard, not an authorization DENY-to-ALLOW correction. 3. Reachability analysis The system administrator must configure `amdgpu.dpm=0`, but that is prior setup rather than proof that the later trigger requires host-admin powers. A local GPU workload might influence thermal activity, yet the evidence does not establish that an unprivileged user can generate the required interrupt reliably. No namespace capability path is shown. The hardware and disabled-DPM configuration are genuine prerequisites; no timing race is identified. 4. Primitive and severity reading The exact defect is scheduling a never-initialized `work_struct`. This is invalid fixed driver state, not a stale post-lifetime object. The patch supports CLASS_C crash/DoS behavior only. Stronger memory corruption or useful exploitation leverage is unproven, so this is not an Important candidate and automatic downgrade is allowed. 5. One-sentence report phrase An AMD SI thermal interrupt can schedule an uninitialized work item when DPM is disabled, plausibly causing a warning, driver failure, or kernel crash without a shown corruption primitive. 6. Manual review advice NO MANUAL CHECK NEEDED The patch shows a configuration-specific initialization guard with no material corruption or security-boundary primitive. 7. Call-site confidence Call-site confidence: high ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/amd/pm/si: Don't schedule thermal work when queue isn't initialized [ Upstream Commit: 2c08ae91df3cf11d517dc1273195f7b1df2a0ddb Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2c08ae91df3cf11d517dc1273195f7b1df2a0ddb Changed files: drivers/gpu/drm/amd/pm/powerplay/si_dpm.c Diff excerpt: Not included in this email. See the upstream URL for the full patch. Full patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2c08ae91df3cf11d517dc1273195f7b1df2a0ddb ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-98898 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98898 The original CVE announcement normally does not include a security-level estimate. In particular, it may not contain a CVSS assessment, an impact level, or enough information to determine whether the reported bug is a practically relevant security issue. One purpose of this parallel CVE list is to provide that missing technical and prioritization information. The original goal of the AL-KERNEL project was to prioritize Linux kernel CVE analysis automatically before manual review. The system can also help identify non-security issues that may be suitable for automatic closure. This report was generated by AL-KERNEL, an AI-assisted Linux kernel vulnerability analysis system developed by Alexander Larkin. The first analysis stage combines an autonomous classifier with additional LLM-based analysis. The autonomous classifier runs locally on a CPU and is based on a backpropagation neural network. Together, these mechanisms produce a technical vulnerability description, identify likely weakness types, estimate CVSS severity, and provide input for ActionableScore. Two CVSS estimates are retained because incomplete kernel vulnerability information often permits more than one defensible interpretation: Conservative CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 4.7 The conservative vector represents a lower-impact interpretation. The Best/paranoid vector intentionally represents a plausible upper-bound interpretation and should not automatically be treated as demonstrated real-world impact. CVSS may also need to be adjusted for a particular Linux deployment, because actual reachability, privileges, enabled kernel configuration, hardware, namespaces, exposed device nodes, and other environmental conditions can differ significantly between systems. A separate ActionableScore mechanism evaluates practical remediation urgency. Its analysis may include reachability, attack prerequisites, subsystem exposure, memory-corruption characteristics, denial-of-service reliability, and possible confidentiality, integrity, or privilege-escalation impact. Conservative ActionableScore: unknown Paranoid ActionableScore: 0 The final base severity is taken directly from the second tab-separated field of the AL-KERNEL classification result. ActionableScore does not replace or independently override that final AL-KERNEL decision, and if ActionableScore adjusted impact level of ALKERNEL, then you would see self-readable flags above like INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7. For an AL-KERNEL result of MODERATE, this report uses the following additional presentation split: ActionableScore below 5 -> MODERATE REGULAR ActionableScore 5 or more -> MODERATE 7.0 The distinction between MODERATE REGULAR and MODERATE 7.0 makes it possible to identify Moderate issues that should receive manual analysis and fixes before lower-priority MODERATE REGULAR issues. In many cases, MODERATE REGULAR fixes may wait for a later rebase or routine update. There is one override in which MODERATE REGULAR becomes MODERATE 7.0 even when the ActionableScore is below 5. When the AL-KERNEL result contains the KPANIC flag, a MODERATE result is always presented as MODERATE 7.0. The KPANIC flag selected with few regexps without usage of AI at all, so it helps to detect cases when Kernel Crash happens and similar (to filter False-Negative results from the LLM usage). KPANIC indicates that a reliable kernel crash, kernel panic, or similarly serious kernel availability impact was identified by the classification workflow. AL-KERNEL base severity for this report: LOW KPANIC detected for this report: NO Published priority for this report (same as in Subject): LOW These results are intended to support engineering triage. They are machine-generated estimates, and cases marked for manual review should be validated by a human security engineer before final disposition. For more info read docs linked from here: https://kernelcve.org/ (and you can submit you own patch there to generate such a report for non-existant CVE-id yet). Note that in many cases this AI tool selects higher severity, than real is (means you can expect Importants instead of Moderate 7.0 or Moderates 7.0 instead of regular Moderates). If you see such cases, please use reply email interface to add additional manual analyses info to this particular CVE. And please, please, let me know when you see Lows instead of Importants or Important instead of Low (because particular for such cases I need to tune this AI tool to make it better for this one and next similar). My contact email for such notifications is alexanjelausa@gmail.com (and both send reply to CVE record itself too and see "reply" button below for howto reply).