From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-53143][IMPORTANT] drm/amdkfd: Fix buffer overflow in SDMA queue checkpoint/restore on GFX11 Date: Thu, 25 Jun 2026 17:42:11 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-53143 X-AL-KERNEL-Priority: IMPORTANT X-AL-KERNEL-Severity: IMPORTANT X-AL-KERNEL-Base-Severity: IMPORTANT X-AL-KERNEL-KPANIC: YES X-AL-KERNEL-ActionableScore: 8 X-AL-KERNEL-ActionableScore-Lower: 7 X-AL-KERNEL-Commit: 16dad1fb0d783a4008de30e32d0038c393de05b1 List-Id: CVE: CVE-2026-53143 Priority: IMPORTANT AL-KERNEL base severity: IMPORTANT KPANIC flag: YES Patch: drm/amdkfd: Fix buffer overflow in SDMA queue checkpoint/restore on GFX11 Commit: 16dad1fb0d783a4008de30e32d0038c393de05b1 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=16dad1fb0d783a4008de30e32d0038c393de05b1 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53143 Analysis date: Thu, 25 Jun 2026 17:42:11 -0400 ActionableScore: 8 ActionableScore lower bound: 7 Actionable bucket: Strong Important candidate / Actionable Moderate at minimum Manual review required: YES Summary: A GFX11 AMD KFD SDMA queue checkpoint/restore bug copies compute MQD sized data for smaller SDMA MQDs, leaking adjacent GTT memory during checkpoint and corrupting adjacent GTT memory during restore, with local PR:L reachability through GPU device access and plausible DoS or privilege escalation impact. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-53143 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53143 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: IMPORTANT Manual review required: YES A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-53143 IMPORTANT CHECK Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H';*CWE-787;CWE-125;CWE-120;BEST CVSS score: '7.8';DESCR 'A buffer overflow in the AMD KFD GFX11 SDMA MQD checkpoint and restore path occurs because SDMA queues were assigned compute MQD handlers that copy 2048 bytes while the SDMA MQD object is only 512 bytes. During checkpoint, a local user with KFD queue access can read 1536 bytes past the SDMA MQD buffer and copy adjacent GTT memory to userspace. During restore, the same size mismatch can write 1536 bytes past the SDMA MQD buffer and corrupt adjacent GTT memory such as ring buffers or neighboring MQDs. For the CVSS the PR:L is used because triggering requires local code execution and access to the AMD KFD or render device, but not necessarily full administrator privileges. The issue is not network reachable. Impact includes information disclosure, memory corruption, denial of service, and a plausible privilege escalation path due to attacker influenced out of bounds writes in GPU queue metadata.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Strong Important candidate / Actionable Moderate at minimum (with actual score 8) SKIP CVE-2026-53143 SKIP No affected files built, so skip this CVE NO - - unknown MAYBE OOB LEAK HARDWARE KPANIC INCREASED_TO_MODERATE_FROM_LOW_BASED_ON_GUESSCVSS KPANIC INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7 - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=8 ActionableScoreLower=7 ## 1. ActionableScore * Conservative score: 7 * Paranoid score: 8 * Final recommended bucket: **Strong Important candidate / Actionable Moderate at minimum**:: ## 2. Signal breakdown * Local unprivileged trigger: +1 A local user with access to AMD KFD or render device nodes can plausibly reach KFD queue checkpoint or restore paths. * Memory corruption, Strong corruption primitive: +2 Restore copies 2048 bytes into a 512 byte SDMA MQD object, causing a 1536 byte OOB write into adjacent GTT memory. * Confidentiality impact plausible: +1 Checkpoint copies 2048 bytes from a 512 byte SDMA MQD object and leaks 1536 bytes of adjacent GTT memory to userspace. * Integrity impact plausible: +1 Restore corrupts adjacent GTT memory, potentially including ring buffers or neighboring MQDs. * Reliable kernel or device DoS concern: +1 Corrupting queue metadata or ring related GTT memory can realistically crash or hang the GPU/KFD path, and possibly destabilize the host graphics/compute stack. * Privilege escalation plausible: +1 conservative, +2 paranoid Conservative scoring treats this as a weak but real LPE concern because the corrupted target is adjacent GPU/KFD metadata rather than a demonstrated kernel heap object takeover. Paranoid scoring treats the attacker influenced OOB write into queue metadata as a plausible stronger escalation primitive. * Privileged kernel/device-management memory corruption path: +1 The corruption occurs in a trusted GPU device-management path involving KFD MQD state and GTT memory. * Hardware/path specificity: -1 The issue is specific to GFX11/Navi3x SDMA queues and checkpoint/restore behavior, not a generic always-on kernel path. ## 3. Reachability analysis The bug is local, not network reachable. The attacker needs local code execution and access to AMD KFD/render device interfaces, which is commonly granted to users in GPU-enabled desktop, compute, or containerized GPU workloads, but is not universal. Namespaces and containers can matter: if a container or reduced-privilege service is given GPU device access, this should not be treated as full host-root privilege. No CAP_SYS_ADMIN assumption is needed for the practical risk model if the relevant device nodes and KFD operations are exposed. The path is hardware and workload dependent: it requires affected GFX11 AMDGPU/KFD support and SDMA queue checkpoint/restore activity. That reduces broad exposure, but the primitive is explicit OOB read plus OOB write once the path is reachable. ## 4. Severity interpretation This behaves more like an Important-class kernel/device vulnerability candidate than an ordinary Moderate. The patch shows a concrete size mismatch causing both information disclosure and memory corruption, not merely a crash or warning. Realistic exploitation evidence is not enough to claim guaranteed privilege escalation, because target placement in adjacent GTT memory and downstream effects need manual validation. However, the OOB write is large, attacker influenced through restore input, and affects trusted GPU queue metadata, so auto-closing as a routine Moderate would be unsafe. ## 5. One-sentence report phrase A GFX11 AMD KFD SDMA queue checkpoint/restore bug copies compute MQD sized data for smaller SDMA MQDs, leaking adjacent GTT memory during checkpoint and corrupting adjacent GTT memory during restore, with local PR:L reachability through GPU device access and plausible DoS or privilege escalation impact. ## 6. Manual review recommendation MANUAL CHECK REQUIRED Explicit OOB read and OOB write are present, the write affects trusted GPU/KFD metadata, and the impact may extend beyond DoS into information disclosure or privilege escalation depending on adjacent object layout and restore controllability. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/amdkfd: Fix buffer overflow in SDMA queue checkpoint/restore on GFX11 Commit: 16dad1fb0d783a4008de30e32d0038c393de05b1 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=16dad1fb0d783a4008de30e32d0038c393de05b1 Commit description: The v11 MQD manager incorrectly assigned the CP-compute variants of checkpoint_mqd/restore_mqd for KFD_MQD_TYPE_SDMA queues. These functions use sizeof(struct v11_compute_mqd) (2048 bytes) instead of sizeof(struct v11_sdma_mqd) (512 bytes), causing a 1536-byte overflow. During CRIU checkpoint of an SDMA queue on Navi3x: - checkpoint_mqd() reads 2048 bytes from a 512-byte SDMA MQD buffer, leaking 1536 bytes of adjacent GTT memory to userspace During CRIU restore: - restore_mqd() writes 2048 bytes into a 512-byte SDMA MQD buffer, corrupting 1536 bytes of adjacent GTT memory (often the ring buffer or neighboring MQDs) This is a copy-paste regression unique to v11. All other ASIC backends (cik, vi, v9, v10, v12) correctly use the SDMA-specific variants. Add checkpoint_mqd_sdma() and restore_mqd_sdma() functions that properly handle the smaller v11_sdma_mqd structure, matching the pattern used in other MQD managers. Fixes: cc009e6 ("drm/amdkfd: Add KFD support for soc21 v3") Assisted-by: Claude:Sonnet 4-5 Signed-off-by: Andrew Martin Acked-by: Alex Deucher Signed-off-by: Alex Deucher (cherry picked from commit 6fa41db ) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman Changed files: drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v11.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=16dad1fb0d783a4008de30e32d0038c393de05b1 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-53143 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-53143 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: Not available The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H The Best / paranoid CVSS score: 7.8 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: 7 Paranoid ActionableScore: 8 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: IMPORTANT KPANIC detected for this report: YES Published priority for this report (same as in Subject): IMPORTANT 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).