Summary
In the Linux kernel, the following vulnerability has been resolved: kasan: avoid sleepable page...
In the Linux kernel, the following vulnerability has been resolved:
kasan: avoid sleepable page allocation from atomic context
apply_to_pte_range() enters the lazy MMU mode and then invokes
kasan_populate_vmalloc_pte() callback on each page table walk iteration.
However, the callback can go into sleep when trying to allocate a single
page, e.g. if an architecutre disables preemption on lazy MMU mode enter.
On s390 if make arch_enter_lazy_mmu_mode() -> preempt_enable() and
arch_leave_lazy_mmu_mode() -> preempt_disable(), such crash occurs:
[ 0.663336] BUG: sleeping function called from invalid context at ./include/linux/sched/mm.h:321
[ 0.663348] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2, name: kthreadd
[ 0.663358] preempt_count: 1, expected: 0
[ 0.663366] RCU nest depth: 0, expected: 0
[ 0.663375] no locks held by kthreadd/2.
[ 0.663383] Preemption disabled at:
[ 0.663386] [<0002f3284cbb4eda>] apply_to_pte_range+0xfa/0x4a0
[ 0.663405] CPU: 0 UID: 0 PID: 2 Comm: kthreadd Not tainted 6.15.0-rc5-gcc-kasan-00043-gd76bb1ebb558-dirty #162 PREEMPT
[ 0.663408] Hardware name: IBM 3931 A01 701 (KVM/Linux)
[ 0.663409] Call Trace:
[ 0.663410] [<0002f3284c385f58>] dump_stack_lvl+0xe8/0x140
[ 0.663413] [<0002f3284c507b9e>] __might_resched+0x66e/0x700
[ 0.663415] [<0002f3284cc4f6c0>] __alloc_frozen_pages_noprof+0x370/0x4b0
[ 0.663419] [<0002f3284ccc73c0>] alloc_pages_mpol+0x1a0/0x4a0
[ 0.663421] [<0002f3284ccc8518>] alloc_frozen_pages_noprof+0x88/0xc0
[ 0.663424] [<0002f3284ccc8572>] alloc_pages_noprof+0x22/0x120
[ 0.663427] [<0002f3284cc341ac>] get_free_pages_noprof+0x2c/0xc0
[ 0.663429] [<0002f3284cceba70>] kasan_populate_vmalloc_pte+0x50/0x120
[ 0.663433] [<0002f3284cbb4ef8>] apply_to_pte_range+0x118/0x4a0
[ 0.663435] [<0002f3284cbc7c14>] apply_to_pmd_range+0x194/0x3e0
[ 0.663437] [<0002f3284cbc99be>] __apply_to_page_range+0x2fe/0x7a0
[ 0.663440] [<0002f3284cbc9e88>] apply_to_page_range+0x28/0x40
[ 0.663442] [<0002f3284ccebf12>] kasan_populate_vmalloc+0x82/0xa0
[ 0.663445] [<0002f3284cc1578c>] alloc_vmap_area+0x34c/0xc10
[ 0.663448] [<0002f3284cc1c2a6>] __get_vm_area_node+0x186/0x2a0
[ 0.663451] [<0002f3284cc1e696>] __vmalloc_node_range_noprof+0x116/0x310
[ 0.663454] [<0002f3284cc1d950>] __vmalloc_node_noprof+0xd0/0x110
[ 0.663457] [<0002f3284c454b88>] alloc_thread_stack_node+0xf8/0x330
[ 0.663460] [<0002f3284c458d56>] dup_task_struct+0x66/0x4d0
[ 0.663463] [<0002f3284c45be90>] copy_process+0x280/0x4b90
[ 0.663465] [<0002f3284c460940>] kernel_clone+0xd0/0x4b0
[ 0.663467] [<0002f3284c46115e>] kernel_thread+0xbe/0xe0
[ 0.663469] [<0002f3284c4e440e>] kthreadd+0x50e/0x7f0
[ 0.663472] [<0002f3284c38c04a>] __ret_from_fork+0x8a/0xf0
[ 0.663475] [<0002f3284ed57ff2>] ret_from_fork+0xa/0x38
Instead of allocating single pages per-PTE, bulk-allocate the shadow
memory prior to applying kasan_populate_vmalloc_pte() callback on a page
range.
Impact
CVE-2025-38029 has a CVSS score of 5.5 (Medium). The vector is requires local access, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2025-38029? CVE-2025-38029 is a medium-severity security vulnerability. No fixed version is listed yet.
- How severe is CVE-2025-38029? CVE-2025-38029 has a CVSS score of 5.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Is there a fix for CVE-2025-38029? No fixed version is listed for CVE-2025-38029 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-38029 exploitable, and should I be worried? Whether CVE-2025-38029 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-38029 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.