# CVE-2023-52490: mm: migrate: fix getting incorrect page mapping during page migration > A race condition during page migration and memory hotplug causes a NULL pointer dereference, leading to a kernel crash and denial of service. - **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:** 29 Feb 2024 - **Updated:** 23 May 2026 - **Also known as:** ALSA-2025:1659, BELL-CVE-2023-52490, DEBIAN-CVE-2023-52490, GHSA-j4qq-hcfp-m638, RHSA-2025:1659, UBUNTU-CVE-2023-52490 ## What is CVE-2023-52490? CVE-2023-52490 is a medium-severity vulnerability in Linux kernel, published on 29 Feb 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: mm: migrate: fix getting incorrect page mapping during page migration When running stress-ng testing, we found below kernel crash after a few hours: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 pc : dentry_name+0xd8/0x224 lr : pointer+0x22c/0x370 sp : ffff800025f134c0 ...... Call trace: dentry_name+0xd8/0x224 pointer+0x22c/0x370 vsnprintf+0x1ec/0x730 vscnprintf+0x2c/0x60 vprintk_store+0x70/0x234 vprintk_emit+0xe0/0x24c vprintk_default+0x3c/0x44 vprintk_func+0x84/0x2d0 printk+0x64/0x88 __dump_page+0x52c/0x530 dump_page+0x14/0x20 set_migratetype_isolate+0x110/0x224 start_isolate_page_range+0xc4/0x20c offline_pages+0x124/0x474 memory_block_offline+0x44/0xf4 memory_subsys_offline+0x3c/0x70 device_offline+0xf0/0x120 ...... After analyzing the vmcore, I found this issue is caused by page migration. The scenario is that, one thread is doing page migration, and we will use the target page's ->mapping field to save 'anon_vma' pointer between page unmap and page move, and now the target page is locked and refcount is 1. Currently, there is another stress-ng thread performing memory hotplug, attempting to offline the target page that is being migrated. It discovers that the refcount of this target page is 1, preventing the offline operation, thus proceeding to dump the page. However, page_mapping() of the target page may return an incorrect file mapping to crash the system in dump_mapping(), since the target page->mapping only saves 'anon_vma' pointer without setting PAGE_MAPPING_ANON flag. There are seveval ways to fix this issue: (1) Setting the PAGE_MAPPING_ANON flag for target page's ->mapping when saving 'anon_vma', but this can confuse PageAnon() for PFN walkers, since the target page has not built mappings yet. (2) Getting the page lock to call page_mapping() in __dump_page() to avoid crashing the system, however, there are still some PFN walkers that call page_mapping() without holding the page lock, such as compaction. (3) Using target page->private field to save the 'anon_vma' pointer and 2 bits page state, just as page->mapping records an anonymous page, which can remove the page_mapping() impact for PFN walkers and also seems a simple way. So I choose option 3 to fix this issue, and this can also fix other potential issues for PFN walkers, such as compaction. Weakness: CWE-476 (NULL Pointer Dereference) ## Which versions are affected by CVE-2023-52490? It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `bpftool` | AlmaLinux:9 | All versions | 7.4.0-503.26.1.el9_5 | | `kernel` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-debug` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-debug-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-debug-devel` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-debug-devel-matched` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-debug-modules` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-debug-modules-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-debug-modules-extra` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-devel` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-devel-matched` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-modules` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-modules-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-64k-modules-extra` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-abi-stablelists` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-cross-headers` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-debug` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-debug-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-debug-devel` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-debug-devel-matched` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-debug-modules` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-debug-modules-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-debug-modules-extra` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-debug-uki-virt` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-devel` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-devel-matched` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-doc` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-headers` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-modules` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-modules-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-modules-extra` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-rt` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-rt-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-rt-debug` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-rt-debug-core` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-rt-debug-devel` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | | `kernel-rt-debug-modules` | AlmaLinux:9 | All versions | 5.14.0-503.26.1.el9_5 | Products: Linux kernel. ## How do I fix CVE-2023-52490? Apply the vendor's patch. ## Is CVE-2023-52490 being exploited? There is no known exploitation of CVE-2023-52490 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-2023-52490 and fix it if it is affected. What it is: CVE-2023-52490 is a medium-severity vulnerability in Linux kernel, published on 29 Feb 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-2023-52490 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-2023-52490/ (Markdown: https://insights.sbomify.com/CVE-2023-52490/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-52490 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-52490 - OSV: https://osv.dev/vulnerability/CVE-2023-52490 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-52490/ Summaries are generated and may contain mistakes; the official description above is the record.