{"cve":"CVE-2022-50517","nvd":{"published":"2025-10-07T16:15:35.367","modified":"2026-08-04T10:18:18.670","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/huge_memory: do not clobber swp_entry_t during THP split\n\nThe following has been observed when running stressng mmap since commit\nb653db77350c (\"mm: Clear page->private when splitting or migrating a page\")\n\n   watchdog: BUG: soft lockup - CPU#75 stuck for 26s! [stress-ng:9546]\n   CPU: 75 PID: 9546 Comm: stress-ng Tainted: G            E      6.0.0-revert-b653db77-fix+ #29 0357d79b60fb09775f678e4f3f64ef0579ad1374\n   Hardware name: SGI.COM C2112-4GP3/X10DRT-P-Series, BIOS 2.0a 05/09/2016\n   RIP: 0010:xas_descend+0x28/0x80\n   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\n   RSP: 0018:ffffbbf02a2236a8 EFLAGS: 00000246\n   RAX: ffff9cab7d6a0002 RBX: ffffe04b0af88040 RCX: 0000000000000002\n   RDX: 0000000000000030 RSI: ffff9cab60509b60 RDI: ffffbbf02a2236c0\n   RBP: 0000000000000000 R08: ffff9cab60509b60 R09: ffffbbf02a2236c0\n   R10: 0000000000000001 R11: ffffbbf02a223698 R12: 0000000000000000\n   R13: ffff9cab4e28da80 R14: 0000000000039c01 R15: ffff9cab4e28da88\n   FS:  00007fab89b85e40(0000) GS:ffff9cea3fcc0000(0000) knlGS:0000000000000000\n   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n   CR2: 00007fab84e00000 CR3: 00000040b73a4003 CR4: 00000000003706e0\n   DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n   DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n   Call Trace:\n    <TASK>\n    xas_load+0x3a/0x50\n    __filemap_get_folio+0x80/0x370\n    ? put_swap_page+0x163/0x360\n    pagecache_get_page+0x13/0x90\n    __try_to_reclaim_swap+0x50/0x190\n    scan_swap_map_slots+0x31e/0x670\n    get_swap_pages+0x226/0x3c0\n    folio_alloc_swap+0x1cc/0x240\n    add_to_swap+0x14/0x70\n    shrink_page_list+0x968/0xbc0\n    reclaim_page_list+0x70/0xf0\n    reclaim_pages+0xdd/0x120\n    madvise_cold_or_pageout_pte_range+0x814/0xf30\n    walk_pgd_range+0x637/0xa30\n    __walk_page_range+0x142/0x170\n    walk_page_range+0x146/0x170\n    madvise_pageout+0xb7/0x280\n    ? asm_common_interrupt+0x22/0x40\n    madvise_vma_behavior+0x3b7/0xac0\n    ? find_vma+0x4a/0x70\n    ? find_vma+0x64/0x70\n    ? madvise_vma_anon_name+0x40/0x40\n    madvise_walk_vmas+0xa6/0x130\n    do_madvise+0x2f4/0x360\n    __x64_sys_madvise+0x26/0x30\n    do_syscall_64+0x5b/0x80\n    ? do_syscall_64+0x67/0x80\n    ? syscall_exit_to_user_mode+0x17/0x40\n    ? do_syscall_64+0x67/0x80\n    ? syscall_exit_to_user_mode+0x17/0x40\n    ? do_syscall_64+0x67/0x80\n    ? do_syscall_64+0x67/0x80\n    ? common_interrupt+0x8b/0xa0\n    entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nThe problem can be reproduced with the mmtests config\nconfig-workload-stressng-mmap.  It does not always happen and when it\ntriggers is variable but it has happened on multiple machines.\n\nThe intent of commit b653db77350c patch was to avoid the case where\nPG_private is clear but folio->private is not-NULL.  However, THP tail\npages uses page->private for \"swp_entry_t if folio_test_swapcache()\" as\nstated in the documentation for struct folio.  This patch only clobbers\npage->private for tail pages if the head page was not in swapcache and\nwarns once if page->private had an unexpected value.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/71e2d666ef85d51834d658830f823560c402b8b6","https://git.kernel.org/stable/c/8cace0eeb03d6043827faa6cf6c9067a9f05cd9f"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:11:26.888974865+00:00"},"epss":{"cve":"CVE-2022-50517","score":0.00147,"percentile":0.03941,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}