From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-80678][MODERATE 7.0] i2c: imx: Fix slave registration race and error handling [ Upstream Date: Fri, 28 Aug 2026 05:10:35 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-80678 X-AL-KERNEL-Priority: MODERATE 7.0 X-AL-KERNEL-Severity: MODERATE 7.0 X-AL-KERNEL-Base-Severity: MODERATE X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 5 X-AL-KERNEL-ActionableScore-Lower: 3 X-AL-KERNEL-Commit: 754bc62f72fd64b202462367134ac8ce95b005de List-Id: CVE: CVE-2026-80678 Priority: MODERATE 7.0 AL-KERNEL base severity: MODERATE KPANIC flag: NO Patch: i2c: imx: Fix slave registration race and error handling [ Upstream Commit: 754bc62f72fd64b202462367134ac8ce95b005de Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=754bc62f72fd64b202462367134ac8ce95b005de Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80678 Analysis date: Fri, 28 Aug 2026 05:10:35 -0400 ActionableScore: 5 ActionableScore lower bound: 3 Actionable bucket: Actionable Moderate at minimum Manual review required: YES Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-80678 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80678 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 7.0 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-2026-80678 MODERATE 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:L/I:L/A:H';CWE-362;**CWE-476;CWE-825;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.8';DESCR 'The i2c imx slave registration path can leave the adapter slave pointer in an inconsistent state when pm_runtime_resume_and_get fails after the pointer was already assigned. A shared IRQ handler can run concurrently and observe this pointer while handling slave events, which can lead to a NULL pointer dereference or a stale pointer use depending on timing and client lifetime. For the CVSS the PR:L is used for the paranoid interpretation because delegated device management, container root, or a service account may be able to trigger slave registration or controller resume paths in some deployments, while typical systems are closer to PR:H. The issue is not network reachable and requires local interaction with the I2C controller or its driver control path. Impact is at least local denial of service via kernel crash, with limited confidentiality or integrity impact kept only for the paranoid score because the race touches pointer validity but does not show a clear arbitrary write primitive.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate at minimum (with actual score 4) YES LOCK NULLPTR USB SIMPLEFIX RACE ERRORPATH LINUS INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5 YES NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=5 ActionableScoreLower=3 1. ActionableScore * Conservative score: 3 * Paranoid score: 5 * Final recommended bucket: **Actionable Moderate at minimum**:: 2. Signal breakdown * Weak/indirect corruption candidate: +1. The shared IRQ handler may observe an invalid or stale `i2c_imx->slave` pointer state during slave registration error handling. * Real lifetime corruption: +1. The bug is about pointer lifetime and synchronization between registration, runtime PM failure, and IRQ-side dereference. * Reliable kernel crash / strong DoS: +1. The commit explicitly describes a possible NULL pointer dereference in the ISR path. * Privileged kernel/device-management memory corruption path: +1. The affected path is an I2C controller driver with runtime PM and IRQ handling, but attacker control is limited. * Availability impact realistic: +1 in the paranoid score. Besides crash risk, the stale non-NULL pointer can also leave the device unable to register a slave again with `-EBUSY`. * Hard or unreliable race / special timing required: -1. The crash depends on shared IRQ concurrency and timing around runtime PM failure. * Requires admin/root/CAP or driver-level control in typical deployments: -2 for the conservative score. Registering I2C slave mode is normally not exposed to ordinary users. * No remote/network signal. This is not network reachable. 3. Reachability analysis Typical triggering requires local control over the I2C slave registration path, device configuration, or a privileged service managing the controller. On standard systems this is closer to admin or driver-level control, so the conservative interpretation is low-to-borderline. In embedded, containerized, or delegated device-management environments, a reduced-privilege service account or container root may be able to exercise the relevant path, so the paranoid interpretation uses a lower privilege assumption. The bug is hardware and driver specific, but i.MX I2C is common enough in embedded deployments that I would not treat it as purely rare. Exploitation requires local interaction and a timing window with runtime PM failure and shared IRQ handling. 4. Severity interpretation This is not an Important-class issue based on the supplied patch alone, because there is no demonstrated attacker-controlled reclaim, arbitrary write, callback control, or strong privilege-escalation primitive. It is more than an ordinary cleanup bug because it combines pointer lifetime, IRQ concurrency, and a concrete NULL dereference crash path. Realistic impact is local DoS and failed device operation. The paranoid score treats stale pointer observation by the ISR as a weak memory lifetime concern that should not be auto-closed without review. 5. One-sentence report phrase A race in i2c imx slave registration can expose a stale or invalid slave pointer to the shared IRQ handler after runtime PM failure, causing local DoS and weak memory lifetime concern requiring manual review. 6. Manual review recommendation MANUAL CHECK REQUIRED. YES REQUIRES MANUAL CHECK. Reason: this is a race involving pointer lifetime and IRQ concurrency, with at least a concrete local DoS and a weak but nonzero stale-pointer concern. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: i2c: imx: Fix slave registration race and error handling [ Upstream Commit: 754bc62f72fd64b202462367134ac8ce95b005de Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=754bc62f72fd64b202462367134ac8ce95b005de Changed files: drivers/i2c/busses/i2c-imx.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=754bc62f72fd64b202462367134ac8ce95b005de ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-80678 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80678 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:L/I:L/A:H The Best / paranoid CVSS score: 5.8 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: 3 Paranoid ActionableScore: 5 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 7.0 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).