From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-68298][LOW] drm/xe/vm: Fix SVM leak on resv obj alloc failure in xe_vm_create() [ Upstream Date: Mon, 10 Aug 2026 13:59:07 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-68298 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: 2 X-AL-KERNEL-ActionableScore-Lower: 1 X-AL-KERNEL-Commit: 279339aa8bdcf9db40094cf2bcbd495c53dbe817 List-Id: CVE: CVE-2026-68298 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: drm/xe/vm: Fix SVM leak on resv obj alloc failure in xe_vm_create() [ Upstream Commit: 279339aa8bdcf9db40094cf2bcbd495c53dbe817 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=279339aa8bdcf9db40094cf2bcbd495c53dbe817 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68298 Analysis date: Mon, 10 Aug 2026 13:59:07 -0400 ActionableScore: 2 ActionableScore lower bound: 1 Actionable bucket: Ordinary Moderate / Low-like Manual review required: NO Summary: A resource leak in the drm/xe VM creation error path can leave gpusvm and pagemap resources unreleased after a reservation object allocation failure, allowing a local user with Xe DRM device access to cause gradual resource exhaustion and denial of service. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-68298 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68298 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-2026-68298 LOW CHECK WITH IMPACT FROM ORIG NN 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-401;*CWE-772;**CWE-400;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.7';DESCR 'A resource leak in the drm/xe VM creation error path can occur after xe_svm_init succeeds and drm_gpuvm_resv_object_alloc fails. Non fault mode VMs can leave gpusvm resources initialized, while fault mode VMs can also keep pagemap owner and pagemap references because the close path is not executed. For the CVSS the PR:L is used because a local process with access to the DRM Xe device or render node can normally reach VM creation interfaces, but reliable triggering also depends on hitting the allocation failure path. The issue is not network reachable and does not show a concrete UAF, OOB access, or arbitrary write primitive. Impact is denial of service through gradual resource exhaustion rather than privilege escalation.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 2) YES LEAK ERRORPATH HARDWARE YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=2 ActionableScoreLower=1 ## 1. ActionableScore * Conservative score: 1 * Paranoid score: 2 * Final recommended bucket: **Ordinary Moderate / Low-like** ## 2. Signal breakdown Conservative: * Local unprivileged trigger: +1. A local process with access to the Intel Xe DRM device or render node can reach VM creation paths in typical desktop or GPU compute deployments. * Availability impact realistic: +1. Repeated triggering can leak gpusvm, pagemap owner, or pagemap references and may eventually cause resource exhaustion. * Hard or unreliable condition: -1. The leak is on an error unwind path after `xe_svm_init()` succeeds and `drm_gpuvm_resv_object_alloc()` fails, so reliable triggering depends on a specific allocation failure condition. Conservative total: 1 Paranoid: * Local unprivileged trigger: +1. DRM render node access can be available to non-root users depending on device permissions. * Availability impact realistic: +1. Sustained abuse could exhaust kernel or GPU VM related resources. * Reliable strong DoS is not awarded separately. The patch describes leaks, not an immediate crash or direct panic path. * No memory corruption signal. The patch fixes missing cleanup, with no UAF, OOB write, double free, type confusion, refcount takeover, arbitrary write, or page-cache corruption shown. * No privilege escalation signal. There is no concrete primitive beyond resource leakage. * Hard or unreliable condition: -1 would normally apply, but for the paranoid score it is effectively balanced by assuming the allocation failure path can be induced under memory pressure. Paranoid total: 2 ## 3. Reachability analysis A local process that can open the Xe DRM device and create VMs can potentially reach the affected path. This is usually PR:L rather than PR:H because render nodes are commonly delegated to non-root desktop, compute, or container workloads, although exact reachability depends on device node permissions and group membership. The issue is not network reachable. Namespaces or containers matter only if the Xe render device is passed through or exposed to the container. The path is hardware and driver dependent and also requires the specific reservation object allocation failure during VM creation, which makes reliable exploitation harder than ordinary ioctl-triggered crashes. Call-site confidence: medium. The provided patch shows the cleanup path and the missing calls, but not the full ioctl entry path or allocation failure controllability. ## 4. Severity interpretation This behaves like an ordinary Moderate or Low-like resource leak rather than an Important-class vulnerability. The realistic impact is local denial of service through gradual resource exhaustion. Theoretical severity is limited because the patch does not show a memory corruption primitive, stale pointer reuse, attacker-controlled reclaim, arbitrary write, information disclosure, or privilege escalation path. ## 5. One-sentence report phrase A resource leak in the drm/xe VM creation error path can leave gpusvm and pagemap resources unreleased after a reservation object allocation failure, allowing a local user with Xe DRM device access to cause gradual resource exhaustion and denial of service. ## 6. Manual review recommendation NO MANUAL CHECK NEEDED This can be processed as low-priority resource-leak triage unless product-specific policy exposes Xe render nodes broadly to untrusted users and resource exhaustion is considered operationally critical. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/xe/vm: Fix SVM leak on resv obj alloc failure in xe_vm_create() [ Upstream Commit: 279339aa8bdcf9db40094cf2bcbd495c53dbe817 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=279339aa8bdcf9db40094cf2bcbd495c53dbe817 Changed files: drivers/gpu/drm/xe/xe_vm.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=279339aa8bdcf9db40094cf2bcbd495c53dbe817 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-68298 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68298 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: 1 Paranoid ActionableScore: 2 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).