From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-43298][LOW] drm/amdgpu: Skip vcn poison irq release on VF [ Upstream Date: Sat, 01 Aug 2026 12:45:04 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-43298 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: 1 X-AL-KERNEL-ActionableScore-Lower: 0 X-AL-KERNEL-Commit: 8ee9aa80d4f1893a6699d46c403a1731548b544b List-Id: CVE: CVE-2026-43298 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: drm/amdgpu: Skip vcn poison irq release on VF [ Upstream Commit: 8ee9aa80d4f1893a6699d46c403a1731548b544b Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8ee9aa80d4f1893a6699d46c403a1731548b544b Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43298 Analysis date: Sat, 01 Aug 2026 12:45:04 -0400 ActionableScore: 1 ActionableScore lower bound: 0 Actionable bucket: Ordinary Moderate / Low-like Manual review required: NO Summary: AMDGPU VCN 2.5 VF cleanup could incorrectly release a RAS poison IRQ that was never enabled, causing a local WARN during driver teardown with possible DoS only on panic_on_warn systems. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-43298 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43298 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-2026-43298 LOW CHECK WITH IMPACT FROM ORIG NN LOW Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H';CWE-703;CWE-754;CWE-404;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.4';DESCR 'A warning in the amdgpu VCN 2.5 cleanup path can occur because a SR-IOV VF does not enable RAS VCN poison IRQ operations, but vcn_v2_5_hw_fini still attempted to release that IRQ during deinitialization. This is a local driver cleanup issue and the observable effect is a WARN or call trace during rmmod or VF cleanup. For the CVSS the PR:H is used because reliable triggering normally requires administrative control over the GPU driver unload, VF lifecycle, or equivalent device management operations. The issue is not network reachable. Impact is mainly availability and log noise, with possible local DoS only on systems where WARN is configured to panic the kernel. No memory corruption, information disclosure, or privilege escalation primitive is supported by the patch context.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 1) SKIP CVE-2026-43298 SKIP No affected files built, so skip this CVE NO - - unknown MAYBE DANGER DMAorINTERRUPT HARDWARE DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=1 ActionableScoreLower=0 ## 1. ActionableScore * Conservative score: 0 * Paranoid score: 1 * Final recommended bucket: **Ordinary Moderate / Low-like**:: ## 2. Signal breakdown * WARN or cleanup-state mismatch: +1 paranoid only. The patch prevents `amdgpu_irq_put()` from being called for a VF path where the VCN RAS poison IRQ was never enabled. * Availability impact: +0 conservative. The demonstrated effect is a WARN/call trace during deinitialization, not a normal kernel panic. * Possible panic-on-warn DoS: +1 paranoid interpretation only, if the system is configured with `panic_on_warn`. * Requires admin/root/device-management privileges: -2. Reliable triggering normally requires `rmmod`, driver teardown, VF lifecycle control, or equivalent GPU management authority. * Rare/config-dependent path: -1. The issue is specific to AMDGPU SR-IOV VF with VCNv2.5/RAS poison IRQ cleanup behavior. * No memory corruption signal: +0. The patch does not show UAF, OOB access, double free, refcount misuse, type confusion, arbitrary write, or stale callback. * No LPE signal: +0. No privilege escalation primitive is supported by the patch. * No confidentiality/integrity signal: +0. No data exposure or modification primitive is shown. Call-site confidence: high. The relevant call site is visible in `vcn_v2_5_hw_fini()` and the fix is a direct conditional skip around `amdgpu_irq_put()`. ## 3. Reachability analysis The bug is locally reachable through AMDGPU driver deinitialization or VF cleanup. In typical deployments this requires administrative control over module unload, GPU device management, or SR-IOV VF lifecycle operations. It is not network reachable. Namespaces or containers do not normally lower this to an unprivileged trigger unless the environment delegates privileged GPU/VF management operations, which would already be an unusual administrative configuration. ## 4. Severity interpretation This behaves like a Low or ordinary Moderate cleanup bug, not an Actionable Moderate and not an Important candidate. The realistic impact is a WARN/call trace during driver cleanup. A paranoid availability concern exists only for systems configured to panic on WARN, but the patch context does not support memory corruption, privilege escalation, information disclosure, or persistent integrity impact. ## 5. One-sentence report phrase AMDGPU VCN 2.5 VF cleanup could incorrectly release a RAS poison IRQ that was never enabled, causing a local WARN during driver teardown with possible DoS only on panic_on_warn systems. ## 6. Manual review recommendation NO MANUAL CHECK NEEDED The issue is admin-triggered, hardware/configuration-specific, and limited to a cleanup WARN without a demonstrated memory corruption or security-boundary bypass primitive. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/amdgpu: Skip vcn poison irq release on VF [ Upstream Commit: 8ee9aa80d4f1893a6699d46c403a1731548b544b Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8ee9aa80d4f1893a6699d46c403a1731548b544b Changed files: drivers/gpu/drm/amd/amdgpu/vcn_v2_5.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=8ee9aa80d4f1893a6699d46c403a1731548b544b ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-43298 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43298 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:L/PR:H/UI:N/S:U/C:N/I:N/A:L The Best / paranoid CVSS vector: AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 4.4 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: 0 Paranoid ActionableScore: 1 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).