Description
In the Linux kernel, the following vulnerability has been resolved:
mm/kmemleak: avoid soft lockup in __kmemleak_do_cleanup()
A soft lockup warning was observed on a relative small system x86-64
system with 16 GB of memory when running a debug kernel with kmemleak
enabled.
watchdog: BUG: soft lockup - CPU#8 stuck for 33s! [kworker/8:1:134]
The test system was running a workload with hot unplug happening in
parallel. Then kemleak decided to disable itself due to its inability to
allocate more kmemleak objects. The debug kernel has its
CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE set to 40,000.
The soft lockup happened in kmemleak_do_cleanup() when the existing
kmemleak objects were being removed and deleted one-by-one in a loop via a
workqueue. In this particular case, there are at least 40,000 objects
that need to be processed and given the slowness of a debug kernel and the
fact that a raw_spinlock has to be acquired and released in
__delete_object(), it could take a while to properly handle all these
objects.
As kmemleak has been disabled in this case, the object removal and
deletion process can be further optimized as locking isn't really needed.
However, it is probably not worth the effort to optimize for such an edge
case that should rarely happen. So the simple solution is to call
cond_resched() at periodic interval in the iteration loop to avoid soft
lockup.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.4 | 5.4.297 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 6.16.3-1 | — |
| Debian 13 | linux | 6.12.43-1 | — |
| Debian 12 | linux | 6.1.153-1 | DSA-6009-1 |
| Debian 11 | linux | 5.10.244-1 | DLA-4327-1 |
| Debian 11 | linux-6.1 | 6.1.153-1~deb11u1 | DLA-4328-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1016.20 | — |
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | 5.15.0-1081.83 | — |
| Ubuntu 25.10 | linux-azure-fde | No fix yet | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-100.100 | USN-8028-1 |
| Ubuntu 24.04 LTS | linux-aws +1 | 6.8.0-1046.49 | USN-8028-5 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1046.52 | USN-8074-1 |
| Ubuntu 24.04 LTS | linux-azure-fde | 6.8.0-1046.53 | — |
| Ubuntu 24.04 LTS | linux-azure-nvidia | 6.8.0-1039.42 | — |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1047.50 | USN-8031-3 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1043.48 | USN-8031-3 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1030.33 | USN-8028-5 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1044.44 | USN-8028-8 |
| Ubuntu 24.04 LTS | linux-intel +19 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-100.100.1 | USN-8052-1 |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1046.49.1 | USN-8028-7 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1020.20 | — |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1043.44 | USN-8028-5 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1047.51 | USN-8028-1 |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1023.24 | USN-8052-2 |
| Ubuntu 22.04 LTS | linux +1 | 5.15.0-163.173 | USN-7909-1 |
| Ubuntu 22.04 LTS | linux-aws | 5.15.0-1097.104 | USN-7909-1 |
| Ubuntu 22.04 LTS | linux-aws-6.8 +1 | 6.8.0-1046.49~22.04.1 | USN-8028-5 |
| Ubuntu 22.04 LTS | linux-azure | 5.15.0-1101.110 | USN-7910-2 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1051.57~22.04.1 | USN-8126-1 |
| Ubuntu 22.04 LTS | linux-azure-fde | 5.15.0-1102.111.1 | — |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1046.53~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-gcp | 5.15.0-1097.106 | USN-7909-4 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1047.50~22.04.2 | USN-8031-1 |
| Ubuntu 22.04 LTS | linux-gke | 5.15.0-1093.99 | USN-7909-4 |
| Ubuntu 22.04 LTS | linux-gkeop | 5.15.0-1080.88 | USN-7909-4 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 +1 | 6.8.0-100.100~22.04.1 | USN-8028-6 |
| Ubuntu 22.04 LTS | linux-ibm +1 | 5.15.0-1091.94 | USN-7909-5, USN-7909-1 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1044.44~22.04.1 | USN-8028-8 |
| Ubuntu 22.04 LTS | linux-intel-iotg | 5.15.0-1092.98 | USN-7909-1 |
| Ubuntu 22.04 LTS | linux-kvm | 5.15.0-1089.94 | USN-7933-1 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-100.100.1~22.04.1 | USN-8028-6 |
| Ubuntu 22.04 LTS | linux-nvidia | 5.15.0-1092.93 | USN-7909-1 |
| Ubuntu 22.04 LTS | linux-nvidia-tegra | 5.15.0-1049.49 | USN-7909-1 |
| Ubuntu 22.04 LTS | linux-nvidia-tegra-igx | 5.15.0-1038.38 | USN-7909-1 |
| Ubuntu 22.04 LTS | linux-oracle | 5.15.0-1094.100 | USN-7909-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1043.44~22.04.1 | USN-8028-5 |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-xilinx-zynqmp | 5.15.0-1061.65 | USN-7909-1 |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2037.38 | USN-8028-3 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1041.42 | USN-8028-3 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-intel-iot-realtime | 5.15.0-1089.91 | USN-7909-2 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime | 5.15.0-1096.105 | USN-7909-2 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1041.42~22.04.1 | USN-8028-2 |
| Ubuntu Pro FIPS 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1046.49+fips1 | USN-8028-4 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1046.52+fips1 | USN-8074-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-100.100+fips1 | USN-8028-4 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1047.50+fips1 | USN-8031-2 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-aws-fips | 5.15.0-1097.104+fips1 | USN-7909-3 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-azure-fips | 5.15.0-1101.110+fips1 | USN-7910-1 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips | 5.15.0-163.173+fips1 | USN-7909-3 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-gcp-fips | 5.15.0-1097.106+fips1 | USN-7909-3 |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux +10 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux-aws-5.15 | 5.15.0-1097.104~20.04.1 | USN-7909-1 |
| Ubuntu Pro 20.04 LTS | linux-azure-5.15 | 5.15.0-1102.111~20.04.1 | USN-7938-1 |
| Ubuntu Pro 20.04 LTS | linux-gcp-5.15 | 5.15.0-1097.106~20.04.1 | USN-7909-1 |
| Ubuntu Pro 20.04 LTS | linux-hwe-5.15 +1 | 5.15.0-163.173~20.04.1 | USN-7909-1 |
| Ubuntu Pro 20.04 LTS | linux-ibm-5.15 | 5.15.0-1091.94~20.04.1 | USN-7909-1 |
| Ubuntu Pro 20.04 LTS | linux-intel-iotg-5.15 | 5.15.0-1092.98~20.04.1 | USN-7909-1 |
| Ubuntu Pro 20.04 LTS | linux-nvidia-tegra-5.15 | 5.15.0-1049.49~20.04.1 | USN-7909-1 |
| Ubuntu Pro 20.04 LTS | linux-oracle-5.15 | 5.15.0-1094.100~20.04.1 | USN-7909-1 |
| Ubuntu Pro 20.04 LTS | linux-riscv-5.15 | 5.15.0-1092.96~20.04.1 | — |
| Ubuntu Pro 18.04 LTS | linux-aws-5.4 +6 | No fix yet | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.104.2-1 | — |
| Azure Linux 2 (CBL-Mariner) | kernel | 5.15.200.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | kernel-uek +6 | 5.4.17-2136.348.3.el8uek | ELSA-2025-20663 |
| Oracle Linux 7 | kernel-uek-tools | 5.4.17-2136.348.3.el7uek | ELSA-2025-20663 |
Advisories 33
- WID-SEC-2025-2040 Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 12, 2026
- USN-7909-1 linux, linux-aws, linux-aws-5.15, linux-gcp-5.15, linux-hwe-5.15, linux-ibm, linux-ibm-5.15, linux-intel-iotg, linux-intel-iotg-5.15, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-nvidia, linux-nvidia-tegra, linux-nvidia-tegra-5.15, linux-nvidia-tegra-igx, linux-oracle, linux-oracle-5.15, linux-xilinx-zynqmp vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-5 linux-aws, linux-aws-6.8, linux-gkeop, linux-nvidia, linux-nvidia-6.8, linux-oracle, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8126-1 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-8 linux-ibm, linux-ibm-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-6 linux-hwe-6.8, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8052-1 linux-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8052-2 linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8074-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8074-2 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8031-3 linux-gcp, linux-gke vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-4 linux-aws-fips, linux-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-1 linux, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-3 linux-realtime, linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-7 linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-2 linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8031-2 linux-gcp-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8031-1 linux-gcp-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7909-3 linux-aws-fips, linux-fips, linux-gcp-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7909-4 linux-gcp, linux-gke, linux-gkeop vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7938-1 linux-azure-5.15 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7933-1 linux-kvm vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7909-5 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7910-2 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7909-2 linux-intel-iot-realtime, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7910-1 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- ICSA-26-134-10 Siemens SIMATIC CISA ICS & IT advisories · May 14, 2026
- NCSC-2026-0147 Kwetsbaarheden verholpen in Siemens-producten NCSC-NL (Netherlands) · May 13, 2026
- SSA-032379 SSA-032379: Multiple Vulnerabilities in SIMATIC CN 4100 Before V5.0 Siemens ProductCERT · May 12, 2026
- DLA-4327-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-6009-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-4328-1 linux-6.1 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- ELSA-2025-20663 Important: Unbreakable Enterprise kernel security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Oct 11, 2025
References
- https://git.kernel.org/stable/c/9f1f4e95031f84867c5821540466d62f88dab8ca
- https://git.kernel.org/stable/c/1ef72a7fedc5bca70e8cc980985790de10d407aa
- https://git.kernel.org/stable/c/a04de4c40aab9b338dfa989cf4aec70fd187eeb2
- https://git.kernel.org/stable/c/f014c10d190b92aad366e56b445daffcd1c075e4
- https://git.kernel.org/stable/c/e21a3ddd58733ce31afcb1e5dc3cb80a4b5bc29b
- https://git.kernel.org/stable/c/8d2d22a55ffe35c38e69795468a7addd1a80e9ce
- https://git.kernel.org/stable/c/926092268efdf1ed7b55cf486356c74a9e7710d1
- https://git.kernel.org/stable/c/9b80430c194e4a114dc663c1025d56b4f3d0153d
- https://git.kernel.org/stable/c/d1534ae23c2b6be350c8ab060803fbf6e9682adc