From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-43369][LOW] drm/amd: Fix NULL pointer dereference in device cleanup Date: Sat, 01 Aug 2026 12:25:25 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-43369 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: 43025c941aced9a9009f9ff20eea4eb78c61deb8 List-Id: CVE: CVE-2026-43369 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: drm/amd: Fix NULL pointer dereference in device cleanup Commit: 43025c941aced9a9009f9ff20eea4eb78c61deb8 Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=43025c941aced9a9009f9ff20eea4eb78c61deb8 Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43369 Analysis date: Sat, 01 Aug 2026 12:25:25 -0400 ActionableScore: 1 ActionableScore lower bound: 0 Actionable bucket: Ordinary Moderate / Low-like Manual review required: NO Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-43369 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43369 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-2026-43369 LOW CHECK WITH IMPACT FROM ORIG NN MODERATE 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-476;CWE-703;CWE-754;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '4.7';DESCR 'A NULL pointer dereference can occur in the AMDGPU cleanup path when GPU initialization fails because an unsupported hardware block leaves an IP block with a NULL version pointer. During teardown, amdgpu_device_set_cg_state() and amdgpu_device_set_pg_state() iterate over IP blocks and may access the version field while applying clock gating or power gating state. For the CVSS the PR:L paranoid case only applies if a local user or reduced privilege service can trigger GPU reset, driver bind/unbind, or recovery paths through delegated permissions. In the typical case administrative control or a specific failing hardware initialization path is required. The issue is not network reachable. Impact is denial of service via kernel crash with C:N/I:N/A:H, and there is no supported evidence for memory corruption or privilege escalation.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 1) MAYBE DANGER NULLPTR SIMPLEFIX HARDWARE DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH 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 * Reliable kernel crash / strong DoS: +1. The patch prevents a concrete NULL pointer dereference in amdgpu_device_set_cg_state() and amdgpu_device_set_pg_state() during failed GPU teardown. * Broad/default/common subsystem: +1 in the paranoid view only. AMDGPU is broadly deployed, but the affected path is not an ordinary runtime userspace data path. * Requires admin/root/CAP_* in typical deployments: -2. Reliable triggering usually requires driver load failure, device teardown, reset, bind/unbind, or hardware management conditions normally controlled by root or system services. * Physical-only or rare hardware-only condition: -2 conservatively. The described trigger depends on GPU initialization failing due to an unsupported HW block, not on a normal attacker-controlled input stream. * Weak corruption: +0. This is a NULL pointer dereference, not UAF, OOB write, double free, type confusion, refcount abuse, or attacker-controlled overwrite. * Privilege escalation plausible: +0. No reclaim, stale callback, writable stale object, object replacement, or other LPE primitive is shown. * Confidentiality impact: +0. * Integrity impact: +0. * Availability impact realistic: not additionally counted beyond the crash signal to avoid double-counting. 3. Reachability analysis The bug is reachable during AMDGPU cleanup after partial initialization failure, when an IP block has status.late_initialized set but version is NULL. In normal deployments, a local unprivileged user generally cannot choose unsupported GPU HW blocks or directly force this exact failed initialization and teardown sequence. A reduced-privilege service or container with delegated device reset or driver management access could make the paranoid PR:L CVSS interpretation plausible, but that is environment-specific. The path is not network reachable. It is hardware and driver-state dependent rather than a broadly exposed kernel API. Call-site confidence: high. The provided patch and commit message identify the direct cleanup callers and the dereferenced field. 4. Severity interpretation This behaves like an ordinary Moderate or Low-like availability issue, not an Important-class vulnerability. The theoretical impact is a kernel crash through NULL pointer dereference during device cleanup. Realistic exploitation evidence for privilege escalation, confidentiality impact, integrity impact, or controllable memory corruption is absent. The most defensible triage outcome is delayed handling or normal maintenance unless the affected product exposes AMDGPU reset or driver management to reduced-privilege users. 5. One-sentence report phrase A NULL pointer dereference in AMDGPU cleanup can crash the kernel after failed GPU initialization leaves an IP block with a NULL version pointer, but exploitation is local or hardware-management dependent and no privilege escalation primitive is evident. 6. Manual review recommendation NO MANUAL CHECK NEEDED. This is a constrained NULL dereference in a cleanup path with no demonstrated memory corruption primitive beyond crash, no network reachability, and typical admin or hardware-specific triggering requirements. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: drm/amd: Fix NULL pointer dereference in device cleanup Commit: 43025c941aced9a9009f9ff20eea4eb78c61deb8 Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=43025c941aced9a9009f9ff20eea4eb78c61deb8 Commit description: When GPU initialization fails due to an unsupported HW block IP blocks may have a NULL version pointer. During cleanup in amdgpu_device_fini_hw, the code calls amdgpu_device_set_pg_state and amdgpu_device_set_cg_state which iterate over all IP blocks and access adev->ip_blocks[i].version without NULL checks, leading to a kernel NULL pointer dereference. Add NULL checks for adev->ip_blocks[i].version in both amdgpu_device_set_cg_state and amdgpu_device_set_pg_state to prevent dereferencing NULL pointers during GPU teardown when initialization has failed. Fixes: 39fc2bc ("drm/amdgpu: Protect GPU register accesses in powergated state in some paths") Reviewed-by: Alex Deucher Signed-off-by: Mario Limonciello Signed-off-by: Alex Deucher (cherry picked from commit b7ac774 ) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman Changed files: drivers/gpu/drm/amd/amdgpu/amdgpu_device.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=43025c941aced9a9009f9ff20eea4eb78c61deb8 ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-43369 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-43369 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:H/UI:N/S:U/C:N/I:N/A:H 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: 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).