From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-80903][MODERATE REGULAR] drm/xe/oa: Fix sync entry leak on OA config emit failure [ Upstream Date: Fri, 04 Sep 2026 14:46:20 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-80903 X-AL-KERNEL-Priority: MODERATE REGULAR X-AL-KERNEL-Severity: MODERATE REGULAR X-AL-KERNEL-Base-Severity: MODERATE X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 3 X-AL-KERNEL-ActionableScore-Lower: 2 X-AL-KERNEL-Commit: fcf7943b0a38568c547d7b5702de1d8190480616 List-Id: CVE: CVE-2026-80903 Priority: MODERATE REGULAR AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: drm/xe/oa: Fix sync entry leak on OA config emit failure [ Upstream Commit: fcf7943b0a38568c547d7b5702de1d8190480616 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=fcf7943b0a38568c547d7b5702de1d8190480616 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80903 Analysis date: Fri, 04 Sep 2026 14:46:20 -0400 ActionableScore: 3 ActionableScore lower bound: 2 Actionable bucket: Ordinary Moderate / Low-like, not an Important candidate Manual review required: NO Summary: A resource leak in the DRM Xe OA config ioctl error path can leave sync entries and dma fence references unreleased after xe_oa_emit_oa_config failure, allowing a local GPU/OA user to cause memory or fence reference exhaustion DoS, with no evidence of memory corruption or privilege escalation. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-80903 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80903 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: MODERATE REGULAR 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-2026-80903 MODERATE https://www.kernelcve.org/list/?q=CVE-2026-80903 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:L/UI:N/S:U/C:N/I:N/A:H';*CWE-401;*CWE-772;CWE-404;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.5';DESCR 'A resource leak in the DRM Xe OA config ioctl path can occur when xe_oa_emit_oa_config fails before completing OA config emission. The failure path can leave the parsed sync array and dma fence references held by sync entries without cleanup, and a later config ioctl can overwrite stream syncs so the leaked objects become permanently unreachable. For the CVSS the PR:L is used because the attacker needs local access to the DRM Xe OA interface, but this access may be available to a non root user through render node permissions, perf related delegation, or a service account with GPU access. The issue is not network reachable and is triggered through a local DRM ioctl rather than packet traffic. Impact is denial of service through memory and fence reference exhaustion. The patch context does not indicate a stale pointer, UAF, OOB access, information leak, or arbitrary write primitive.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like, not an Important candidate (with actual score 3) YES SIMPLEFIX LEAK ERRORPATH HARDWARE INCREASED_FROM_LOW_BASED_ON_HIGHCVSSSCORE DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=3 ActionableScoreLower=2 ## 1. ActionableScore * Conservative score: 2 * Paranoid score: 3 * Final recommended bucket: **Ordinary Moderate / Low-like, not an Important candidate**:: ## 2. Signal breakdown Conservative signals: * Local unprivileged trigger: +1. The issue is reachable through a local DRM Xe OA config ioctl by a process with access to the relevant GPU/OA interface. * Real lifetime / reference handling bug: +1. The bug leaks parsed sync entries and dma fence references on an error path. * Availability impact realistic: +1. Repeated failures may accumulate leaked memory and fence references and cause resource exhaustion. * Rare / configuration-dependent subsystem: -1. This requires Intel Xe DRM OA support, an OA stream, and an error during OA config emission. Conservative total: 2 Paranoid additional interpretation: * Reliable strong DoS concern: +1. If a local user can repeatedly force the failing config path, sustained leaks may create a practical resource exhaustion DoS. Paranoid total: 3 No memory corruption signal is awarded. The patch shows a leak of memory and fence references, not UAF, double free, OOB access, stale callback, type confusion, arbitrary write, or page-cache/shared-page corruption. ## 3. Reachability analysis The trigger is local through the DRM Xe OA configuration path. It is not network reachable. In typical deployments, access depends on GPU device permissions and OA/perf policy, so this is not equivalent to full host root but is also not a universal unprivileged interface. Containers or service accounts with delegated GPU access may make the path reachable without full administrative privileges. Realistic exploitation requires repeatedly reaching an OA config emit failure before cleanup, so the practical impact is resource exhaustion rather than immediate compromise. Call-site confidence: medium. The provided patch and commit message clearly show the failing caller path in xe_oa_config_locked and the missing cleanup of param.syncs and sync entry fence references, but broader access-control details for the OA ioctl are not included. ## 4. Severity interpretation This behaves like an ordinary Moderate or Low-like local resource leak. The realistic impact is denial of service through memory and fence reference exhaustion. There is no supported privilege escalation path and no demonstrated confidentiality or integrity impact. The paranoid score is slightly higher only because repeated local triggering could make the resource exhaustion more operationally relevant. ## 5. One-sentence report phrase A resource leak in the DRM Xe OA config ioctl error path can leave sync entries and dma fence references unreleased after xe_oa_emit_oa_config failure, allowing a local GPU/OA user to cause memory or fence reference exhaustion DoS, with no evidence of memory corruption or privilege escalation. ## 6. Manual review recommendation NO MANUAL CHECK NEEDED. This can be auto-closed or handled in deferred mode unless the affected product exposes Xe OA ioctls broadly to untrusted users or there is separate evidence that the leaked fence references can trigger a stronger cross-process or memory-corruption primitive. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/xe/oa: Fix sync entry leak on OA config emit failure [ Upstream Commit: fcf7943b0a38568c547d7b5702de1d8190480616 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=fcf7943b0a38568c547d7b5702de1d8190480616 Changed files: drivers/gpu/drm/xe/xe_oa.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=fcf7943b0a38568c547d7b5702de1d8190480616 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-80903 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80903 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:L/PR:L/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 5.5 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: 2 Paranoid ActionableScore: 3 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: MODERATE KPANIC detected for this report: NO Published priority for this report (same as in Subject): MODERATE REGULAR 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).