CVE-2025-39843
Vulnerability Summary
Timeline
Description
In the Linux kernel, the following vulnerability has been resolved: mm: slub: avoid wake up kswapd in set_track_prepare set_track_prepare() can incur lock recursion. The issue is that it is called from hrtimer_start_range_ns holding the per_cpu(hrtimer_bases)[n].lock, but when enabled CONFIG_DEBUG_OBJECTS_TIMERS, may wake up kswapd in set_track_prepare, and try to hold the per_cpu(hrtimer_bases)[n].lock. Avoid deadlock caused by implicitly waking up kswapd by passing in allocation flags, which do not contain __GFP_KSWAPD_RECLAIM in the debug_objects_fill_pool() case. Inside stack depot they are processed by gfp_nested_mask(). Since ___slab_alloc() has preemption disabled, we mask out __GFP_DIRECT_RECLAIM from the flags there. The oops looks something like: BUG: spinlock recursion on CPU#3, swapper/3/0 lock: 0xffffff8a4bf29c80, .magic: dead4ead, .owner: swapper/3/0, .owner_cpu: 3 Hardware name: Qualcomm Technologies, Inc. Popsicle based on SM8850 (DT) Call trace: spin_bug+0x0 _raw_spin_lock_irqsave+0x80 hrtimer_try_to_cancel+0x94 task_contending+0x10c enqueue_dl_entity+0x2a4 dl_server_start+0x74 enqueue_task_fair+0x568 enqueue_task+0xac do_activate_task+0x14c ttwu_do_activate+0xcc try_to_wake_up+0x6c8 default_wake_function+0x20 autoremove_wake_function+0x1c __wake_up+0xac wakeup_kswapd+0x19c wake_all_kswapds+0x78 __alloc_pages_slowpath+0x1ac __alloc_pages_noprof+0x298 stack_depot_save_flags+0x6b0 stack_depot_save+0x14 set_track_prepare+0x5c ___slab_alloc+0xccc __kmalloc_cache_noprof+0x470 __set_page_owner+0x2bc post_alloc_hook[jt]+0x1b8 prep_new_page+0x28 get_page_from_freelist+0x1edc __alloc_pages_noprof+0x13c alloc_slab_page+0x244 allocate_slab+0x7c ___slab_alloc+0x8e8 kmem_cache_alloc_noprof+0x450 debug_objects_fill_pool+0x22c debug_object_activate+0x40 enqueue_hrtimer[jt]+0xdc hrtimer_start_range_ns+0x5f8 ...
CVSS Metrics
- v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS Trends
Current EPSS score: 0.11%• Percentile: 2%
Techniques & Countermeasures
- CWE-667•Improper Locking
The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.
Affected Systems
- debian•linux
< 6.1.153-1 | < 6.12.48-1 | < 6.16.6-1
- debian•linux-6.1
< 6.1.153-1~deb11u1
- ubuntu•linux
< 6.8.0-106.106
- ubuntu•linux-allwinner-5.19
all
- ubuntu•linux-aws
< 6.8.0-1050.53
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.11
all
- ubuntu•linux-aws-5.13
all
- ubuntu•linux-aws-5.19
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.8
all
- ubuntu•linux-aws-6.14
all
- ubuntu•linux-aws-6.2
all
- ubuntu•linux-aws-6.5
all
- ubuntu•linux-aws-6.8
< 6.8.0-1050.53~22.04.1
- ubuntu•linux-aws-fips
< 6.8.0-1050.53+fips1
- ubuntu•linux-azure
all | < 6.8.0-1051.57
- ubuntu•linux-azure-5.11
all
- ubuntu•linux-azure-5.13
all
- ubuntu•linux-azure-5.19
all
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.8
all
- ubuntu•linux-azure-6.11
all
- ubuntu•linux-azure-6.14
all
- ubuntu•linux-azure-6.2
all
- ubuntu•linux-azure-6.5
all
- ubuntu•linux-azure-6.8
< 6.8.0-1051.57~22.04.1
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fde
all | all | all
- ubuntu•linux-azure-fde-5.19
all
- ubuntu•linux-azure-fde-6.14
all
- ubuntu•linux-azure-fde-6.2
all
- ubuntu•linux-azure-fde-6.8
all
- ubuntu•linux-azure-fips
< 6.8.0-1052.58+fips1
- ubuntu•linux-azure-nvidia
all
- ubuntu•linux-azure-nvidia-6.14
all
- ubuntu•linux-bluefield
all | < 6.8.0-1017.21
- ubuntu•linux-fips
< 6.8.0-106.106+fips1
- ubuntu•linux-gcp
all | < 6.8.0-1052.55
- ubuntu•linux-gcp-5.11
all
- ubuntu•linux-gcp-5.13
all
- ubuntu•linux-gcp-5.19
all
- ubuntu•linux-gcp-5.3
all
- ubuntu•linux-gcp-5.8
all
- ubuntu•linux-gcp-6.11
all
- ubuntu•linux-gcp-6.14
all
- ubuntu•linux-gcp-6.2
all
- ubuntu•linux-gcp-6.5
all
- ubuntu•linux-gcp-6.8
< 6.8.0-1052.55~22.04.1
- ubuntu•linux-gcp-fips
< 6.8.0-1052.55+fips1
Showing first 50 affected entries in server-rendered view.
References (21)
- https://git.kernel.org/stable/c/994b03b9605d36d814c611385fbf90ca6db20aa8
- https://git.kernel.org/stable/c/522ffe298627cfe72539d72167c2e20e72b5e856
- https://git.kernel.org/stable/c/243b705a90ed8449f561a271cf251fd2e939f3db
- https://git.kernel.org/stable/c/eb3240ffd243bfb8b1e9dc568d484ecf9fd660ab
- https://git.kernel.org/stable/c/850470a8413a8a78e772c4f6bd9fe81ec6bd5b0f
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
- https://ubuntu.com/security/CVE-2025-39843
- https://www.cve.org/CVERecord?id=CVE-2025-39843
- https://git.kernel.org/linus/850470a8413a8a78e772c4f6bd9fe81ec6bd5b0f
- https://ubuntu.com/security/notices/USN-8095-1
- https://ubuntu.com/security/notices/USN-8100-1
- https://ubuntu.com/security/notices/USN-8095-2
- https://ubuntu.com/security/notices/USN-8095-3
- https://ubuntu.com/security/notices/USN-8095-4
- https://ubuntu.com/security/notices/USN-8125-1
- https://ubuntu.com/security/notices/USN-8126-1
- https://ubuntu.com/security/notices/USN-8095-5
- https://ubuntu.com/security/notices/USN-8165-1
- https://ubuntu.com/security/notices/USN-8261-1
- https://security-tracker.debian.org/tracker/CVE-2025-39843