# CVE-2022-50517: mm/huge_memory: do not clobber swp_entry_t during THP split > A bug in the Linux kernel's Transparent Huge Page split logic causes a soft lockup, leading to system denial of service. - **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 7 Oct 2025 - **Updated:** 5 Aug 2026 - **Also known as:** DEBIAN-CVE-2022-50517, GHSA-8jc8-9g79-v496, UBUNTU-CVE-2022-50517 ## What is CVE-2022-50517? CVE-2022-50517 is a high-severity denial of service vulnerability in Linux kernel, published on 7 Oct 2025. 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/huge_memory: do not clobber swp_entry_t during THP split The following has been observed when running stressng mmap since commit b653db77350c ("mm: Clear page->private when splitting or migrating a page") watchdog: BUG: soft lockup - CPU#75 stuck for 26s! [stress-ng:9546] CPU: 75 PID: 9546 Comm: stress-ng Tainted: G E 6.0.0-revert-b653db77-fix+ #29 0357d79b60fb09775f678e4f3f64ef0579ad1374 Hardware name: SGI.COM C2112-4GP3/X10DRT-P-Series, BIOS 2.0a 05/09/2016 RIP: 0010:xas_descend+0x28/0x80 Code: cc cc 0f b6 0e 48 8b 57 08 48 d3 ea 83 e2 3f 89 d0 48 83 c0 04 48 8b 44 c6 08 48 89 77 18 48 89 c1 83 e1 03 48 83 f9 02 75 08 <48> 3d fd 00 00 00 76 08 88 57 12 c3 cc cc cc cc 48 c1 e8 02 89 c2 RSP: 0018:ffffbbf02a2236a8 EFLAGS: 00000246 RAX: ffff9cab7d6a0002 RBX: ffffe04b0af88040 RCX: 0000000000000002 RDX: 0000000000000030 RSI: ffff9cab60509b60 RDI: ffffbbf02a2236c0 RBP: 0000000000000000 R08: ffff9cab60509b60 R09: ffffbbf02a2236c0 R10: 0000000000000001 R11: ffffbbf02a223698 R12: 0000000000000000 R13: ffff9cab4e28da80 R14: 0000000000039c01 R15: ffff9cab4e28da88 FS: 00007fab89b85e40(0000) GS:ffff9cea3fcc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fab84e00000 CR3: 00000040b73a4003 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: xas_load+0x3a/0x50 __filemap_get_folio+0x80/0x370 ? put_swap_page+0x163/0x360 pagecache_get_page+0x13/0x90 __try_to_reclaim_swap+0x50/0x190 scan_swap_map_slots+0x31e/0x670 get_swap_pages+0x226/0x3c0 folio_alloc_swap+0x1cc/0x240 add_to_swap+0x14/0x70 shrink_page_list+0x968/0xbc0 reclaim_page_list+0x70/0xf0 reclaim_pages+0xdd/0x120 madvise_cold_or_pageout_pte_range+0x814/0xf30 walk_pgd_range+0x637/0xa30 __walk_page_range+0x142/0x170 walk_page_range+0x146/0x170 madvise_pageout+0xb7/0x280 ? asm_common_interrupt+0x22/0x40 madvise_vma_behavior+0x3b7/0xac0 ? find_vma+0x4a/0x70 ? find_vma+0x64/0x70 ? madvise_vma_anon_name+0x40/0x40 madvise_walk_vmas+0xa6/0x130 do_madvise+0x2f4/0x360 __x64_sys_madvise+0x26/0x30 do_syscall_64+0x5b/0x80 ? do_syscall_64+0x67/0x80 ? syscall_exit_to_user_mode+0x17/0x40 ? do_syscall_64+0x67/0x80 ? syscall_exit_to_user_mode+0x17/0x40 ? do_syscall_64+0x67/0x80 ? do_syscall_64+0x67/0x80 ? common_interrupt+0x8b/0xa0 entry_SYSCALL_64_after_hwframe+0x63/0xcd The problem can be reproduced with the mmtests config config-workload-stressng-mmap. It does not always happen and when it triggers is variable but it has happened on multiple machines. The intent of commit b653db77350c patch was to avoid the case where PG_private is clear but folio->private is not-NULL. However, THP tail pages uses page->private for "swp_entry_t if folio_test_swapcache()" as stated in the documentation for struct folio. This patch only clobbers page->private for tail pages if the head page was not in swapcache and warns once if page->private had an unexpected value. ## Which versions are affected by CVE-2022-50517? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2022-50517? Apply the vendor's patch. ## Is CVE-2022-50517 being exploited? There is no known exploitation of CVE-2022-50517 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-2022-50517 and fix it if it is affected. What it is: CVE-2022-50517 is a high-severity denial of service vulnerability in Linux kernel, published on 7 Oct 2025. 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-2022-50517 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-2022-50517/ (Markdown: https://insights.sbomify.com/CVE-2022-50517/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2022-50517 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-50517 - OSV: https://osv.dev/vulnerability/CVE-2022-50517 --- From sbomify Insights: https://insights.sbomify.com/CVE-2022-50517/ Summaries are generated and may contain mistakes; the official description above is the record.