From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-45961][LOW] gfs2: fix memory leaks in gfs2_fill_super error path [ Upstream Date: Wed, 27 May 2026 19:16:09 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-45961 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: unknown X-AL-KERNEL-Commit: e54229ecf49add8451d5f765a32c86ab4446e06c List-Id: CVE: CVE-2026-45961 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: gfs2: fix memory leaks in gfs2_fill_super error path [ Upstream Commit: e54229ecf49add8451d5f765a32c86ab4446e06c Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=e54229ecf49add8451d5f765a32c86ab4446e06c Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-45961 Analysis date: Wed, 27 May 2026 19:16:09 -0400 ActionableScore: 1 ActionableScore lower bound: unknown 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-2026-45961 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-45961 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-2026-45961 LOW CHECK 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-404;CWE-703;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '4.7';DESCR 'gfs2 mount error handling can leak kernel threads and quota bitmap memory when the filesystem fails while transitioning to read write mode. A failed gfs2_fill_super() path can leave logd or quotad kthreads alive, and a failed gfs2_make_fs_rw() path after quota initialization can leave the quota bitmap allocated. For the CVSS the PR:L is used only in the paranoid score because delegated mount helpers or containerized mount workflows may let a reduced privilege actor trigger repeated mount failures, while direct mounting normally requires administrator privileges. The issue is not network reachable and does not provide a memory corruption primitive. Impact is availability only through resource leakage under repeated error conditions.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate / Low-like (with actual score 1) MAYBE DISK LEAK ERRORPATH IMPROVEONLY LINUS SYZBOT - - checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=1 1. ActionableScore * Conservative score: 1 * Paranoid score: 1 * Final recommended bucket: **Ordinary Moderate / Low-like**:: 2. Signal breakdown * Availability/resource leak concern: +1. Failed GFS2 mount paths can leak kthreads and an 8192-byte quota bitmap. * Important filesystem/storage path: +1. The issue is in GFS2 mount/read-write transition handling. * Requires admin/root/CAP_SYS_ADMIN in typical deployments: -2. Directly mounting GFS2 filesystems normally requires administrative privileges. * Resource leak only. No UAF, OOB write, arbitrary write, information disclosure, or privilege escalation primitive is shown. * No network trigger. The issue is local mount/error-path handling. 3. Reachability analysis The trigger is a failed GFS2 mount or read-write transition after partial initialization. In normal deployments, this requires `CAP_SYS_ADMIN` or equivalent mount control. Delegated mount helpers or containerized workflows could lower practical privilege, but the bug still requires repeated failed mount attempts and specific error conditions such as freeze-lock failure or filesystem withdrawal. It is not network reachable. 4. Severity interpretation This behaves like a Low-like resource leak. The realistic impact is gradual resource exhaustion from leaked kthreads or quota buffers under repeated failed mount attempts. There is no memory corruption, confidentiality impact, integrity impact, or LPE evidence. 5. One-sentence report phrase GFS2 mount error paths can leak log or quota kernel threads and quota bitmap memory after read-write transition failures, causing only resource-exhaustion DoS under repeated failures. 6. Manual review recommendation NO MANUAL CHECK NEEDED. This is a privileged or delegated mount error-path resource leak with no memory corruption or security-boundary bypass primitive. ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: gfs2: fix memory leaks in gfs2_fill_super error path [ Upstream Commit: e54229ecf49add8451d5f765a32c86ab4446e06c Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=e54229ecf49add8451d5f765a32c86ab4446e06c Changed files: kernel/fork.c kernel/kthread.c fs/gfs2/ops_fstype.c fs/gfs2/quota.c fs/gfs2/super.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=e54229ecf49add8451d5f765a32c86ab4446e06c ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-45961 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-45961 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: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: unknown 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).