{"cve":"CVE-2025-38029","nvd":{"published":"2025-06-18T10:15:34.970","modified":"2026-10-21T13:18:07.740","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nkasan: avoid sleepable page allocation from atomic context\n\napply_to_pte_range() enters the lazy MMU mode and then invokes\nkasan_populate_vmalloc_pte() callback on each page table walk iteration. \nHowever, the callback can go into sleep when trying to allocate a single\npage, e.g.  if an architecutre disables preemption on lazy MMU mode enter.\n\nOn s390 if make arch_enter_lazy_mmu_mode() -> preempt_enable() and\narch_leave_lazy_mmu_mode() -> preempt_disable(), such crash occurs:\n\n[    0.663336] BUG: sleeping function called from invalid context at ./include/linux/sched/mm.h:321\n[    0.663348] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2, name: kthreadd\n[    0.663358] preempt_count: 1, expected: 0\n[    0.663366] RCU nest depth: 0, expected: 0\n[    0.663375] no locks held by kthreadd/2.\n[    0.663383] Preemption disabled at:\n[    0.663386] [<0002f3284cbb4eda>] apply_to_pte_range+0xfa/0x4a0\n[    0.663405] CPU: 0 UID: 0 PID: 2 Comm: kthreadd Not tainted 6.15.0-rc5-gcc-kasan-00043-gd76bb1ebb558-dirty #162 PREEMPT\n[    0.663408] Hardware name: IBM 3931 A01 701 (KVM/Linux)\n[    0.663409] Call Trace:\n[    0.663410]  [<0002f3284c385f58>] dump_stack_lvl+0xe8/0x140\n[    0.663413]  [<0002f3284c507b9e>] __might_resched+0x66e/0x700\n[    0.663415]  [<0002f3284cc4f6c0>] __alloc_frozen_pages_noprof+0x370/0x4b0\n[    0.663419]  [<0002f3284ccc73c0>] alloc_pages_mpol+0x1a0/0x4a0\n[    0.663421]  [<0002f3284ccc8518>] alloc_frozen_pages_noprof+0x88/0xc0\n[    0.663424]  [<0002f3284ccc8572>] alloc_pages_noprof+0x22/0x120\n[    0.663427]  [<0002f3284cc341ac>] get_free_pages_noprof+0x2c/0xc0\n[    0.663429]  [<0002f3284cceba70>] kasan_populate_vmalloc_pte+0x50/0x120\n[    0.663433]  [<0002f3284cbb4ef8>] apply_to_pte_range+0x118/0x4a0\n[    0.663435]  [<0002f3284cbc7c14>] apply_to_pmd_range+0x194/0x3e0\n[    0.663437]  [<0002f3284cbc99be>] __apply_to_page_range+0x2fe/0x7a0\n[    0.663440]  [<0002f3284cbc9e88>] apply_to_page_range+0x28/0x40\n[    0.663442]  [<0002f3284ccebf12>] kasan_populate_vmalloc+0x82/0xa0\n[    0.663445]  [<0002f3284cc1578c>] alloc_vmap_area+0x34c/0xc10\n[    0.663448]  [<0002f3284cc1c2a6>] __get_vm_area_node+0x186/0x2a0\n[    0.663451]  [<0002f3284cc1e696>] __vmalloc_node_range_noprof+0x116/0x310\n[    0.663454]  [<0002f3284cc1d950>] __vmalloc_node_noprof+0xd0/0x110\n[    0.663457]  [<0002f3284c454b88>] alloc_thread_stack_node+0xf8/0x330\n[    0.663460]  [<0002f3284c458d56>] dup_task_struct+0x66/0x4d0\n[    0.663463]  [<0002f3284c45be90>] copy_process+0x280/0x4b90\n[    0.663465]  [<0002f3284c460940>] kernel_clone+0xd0/0x4b0\n[    0.663467]  [<0002f3284c46115e>] kernel_thread+0xbe/0xe0\n[    0.663469]  [<0002f3284c4e440e>] kthreadd+0x50e/0x7f0\n[    0.663472]  [<0002f3284c38c04a>] __ret_from_fork+0x8a/0xf0\n[    0.663475]  [<0002f3284ed57ff2>] ret_from_fork+0xa/0x38\n\nInstead of allocating single pages per-PTE, bulk-allocate the shadow\nmemory prior to applying kasan_populate_vmalloc_pte() callback on a page\nrange.","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/468e7d51dba433a72dcd63eee6db9ad721d39ac5","https://git.kernel.org/stable/c/6748dd09196248b985cca39eaf651d5317271977","https://git.kernel.org/stable/c/b6ea95a34cbd014ab6ade4248107b86b0aaf2d6c","https://git.kernel.org/stable/c/c33a7fe6dda591694cebfe15abf4644abb4f61c0"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2025-38029","score":0.00237,"percentile":0.14569,"date":"2026-10-25"},"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."]}