# CVE-2024-50022: device-dax: correct pgoff align in dax_set_mapping() > Incorrect alignment in device-dax causes infinite MCE loops and kernel panic when handling memory errors on non-aligned addresses. - **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Local or same network only - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 21 Oct 2024 - **Updated:** 11 May 2026 - **Also known as:** AZL-51386, BELL-CVE-2024-50022, DEBIAN-CVE-2024-50022, GHSA-g9c5-q45g-cc74, UBUNTU-CVE-2024-50022 ## What is CVE-2024-50022? CVE-2024-50022 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 Oct 2024. It can only be exploited from the same machine or local network, with no action from the victim. ### Official description In the Linux kernel, the following vulnerability has been resolved: device-dax: correct pgoff align in dax_set_mapping() pgoff should be aligned using ALIGN_DOWN() instead of ALIGN(). Otherwise, vmf->address not aligned to fault_size will be aligned to the next alignment, that can result in memory failure getting the wrong address. It's a subtle situation that only can be observed in page_mapped_in_vma() after the page is page fault handled by dev_dax_huge_fault. Generally, there is little chance to perform page_mapped_in_vma in dev-dax's page unless in specific error injection to the dax device to trigger an MCE - memory-failure. In that case, page_mapped_in_vma() will be triggered to determine which task is accessing the failure address and kill that task in the end. We used self-developed dax device (which is 2M aligned mapping) , to perform error injection to random address. It turned out that error injected to non-2M-aligned address was causing endless MCE until panic. Because page_mapped_in_vma() kept resulting wrong address and the task accessing the failure address was never killed properly: [ 3783.719419] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3784.049006] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3784.049190] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3784.448042] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3784.448186] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3784.792026] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3784.792179] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3785.162502] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3785.162633] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3785.461116] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3785.461247] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3785.764730] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3785.764859] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3786.042128] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3786.042259] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3786.464293] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3786.464423] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3786.818090] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3786.818217] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3787.085297] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3787.085424] Memory failure: 0x200c9742: recovery action for dax page: Recovered It took us several weeks to pinpoint this problem,  but we eventually used bpftrace to trace the page fault and mce address and successfully identified the issue. Joao added: ; Likely we never reproduce in production because we always pin : device-dax regions in the region align they provide (Qemu does : similarly with prealloc in hugetlb/file backed memory). I think this : bug requires that we touch *unpinned* device-dax regions unaligned to : the device-dax selected alignment (page size i.e. 4K/2M/1G) ## Which versions are affected by CVE-2024-50022? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2024-50022? Apply the vendor's patch. ## Is CVE-2024-50022 being exploited? There is no known exploitation of CVE-2024-50022 in the wild and no public exploit code. ## Other vulnerabilities in Linux kernel - [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild) - [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild) - [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild) - [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild) - [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2024-50022 and fix it if it is affected. What it is: CVE-2024-50022 is a medium-severity denial of service vulnerability in Linux kernel, published on 21 Oct 2024. It can only be exploited from the same machine or local network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2024-50022 in the wild and no public exploit code. Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2024-50022/ (Markdown: https://insights.sbomify.com/CVE-2024-50022/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2024-50022 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-50022 - OSV: https://osv.dev/vulnerability/CVE-2024-50022 --- From sbomify Insights: https://insights.sbomify.com/CVE-2024-50022/ Summaries are generated and may contain mistakes; the official description above is the record.