Description
In the Linux kernel, the following vulnerability has been resolved:
mm/page_alloc: fix race condition in unaccepted memory handling
The page allocator tracks the number of zones that have unaccepted memory
using static_branch_enc/dec() and uses that static branch in hot paths to
determine if it needs to deal with unaccepted memory.
Borislav and Thomas pointed out that the tracking is racy: operations on
static_branch are not serialized against adding/removing unaccepted pages
to/from the zone.
Sanity checks inside static_branch machinery detects it:
WARNING: CPU: 0 PID: 10 at kernel/jump_label.c:276 __static_key_slow_dec_cpuslocked+0x8e/0xa0
The comment around the WARN() explains the problem:
/*
* Warn about the '-1' case though; since that means a
* decrement is concurrent with a first (0->1) increment. IOW
* people are trying to disable something that wasn't yet fully
* enabled. This suggests an ordering problem on the user side.
*/
The effect of this static_branch optimization is only visible on
microbenchmark.
Instead of adding more complexity around it, remove it altogether.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.5 | 6.6.92 |
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 | 6.12.30-1 | — |
| Debian 13 | linux | 6.12.30-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1016.20 | — |
| Ubuntu 25.10 | linux-azure-fde | No fix yet | — |
| Ubuntu 25.04 | linux-azure | 6.14.0-1010.10 | USN-7721-1 |
| 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-aws-6.14 +1 | 6.14.0-1011.11~24.04.1 | USN-7699-1 |
| 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-gcp-6.14 | 6.14.0-1014.15~24.04.1 | USN-7699-1 |
| 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-hwe-6.14 | 6.14.0-28.28~24.04.1 | USN-7699-2 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1044.44 | USN-8028-8 |
| Ubuntu 24.04 LTS | linux-intel +10 | 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-oem-6.14 | 6.14.0-1010.10 | USN-7699-2 |
| 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-riscv-6.14 | 6.14.0-28.28.1~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1023.24 | USN-8052-2 |
| 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-6.8 | 6.8.0-1051.57~22.04.1 | USN-8126-1 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1046.53~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1047.50~22.04.2 | USN-8031-1 |
| 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-6.8 | 6.8.0-1044.44~22.04.1 | USN-8028-8 |
| 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-oracle-6.8 | 6.8.0-1043.44~22.04.1 | USN-8028-5 |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
Show 6 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 | 6.14.0-1010.10~24.04.1 | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1041.42~22.04.1 | USN-8028-2 |
| 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 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +6 | 6.4.0-150700.53.22.1 | SUSE-SU-2025:4057-1 |
| SLES 15 SP7 | kernel-azure +2 | 6.4.0-150700.20.18.1 | SUSE-SU-2025:4132-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.22.1.150700.17.15.1 | SUSE-SU-2025:4057-1 |
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.78.1 | SUSE-SU-2025:4140-1 |
| SLES 15 SP6 | kernel-azure +2 | 6.4.0-150600.8.55.1 | SUSE-SU-2025:4128-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.78.1.150600.12.34.2 | SUSE-SU-2025:4140-1 |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +7 | 6.12.0-160000.6.1 | SUSE-SU-2025:21139-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.6.1.160000.2.4 | SUSE-SU-2025:21139-1 |
| SLES 16.0 | kernel-64kb +7 | 6.12.0-160000.6.1 | SUSE-SU-2025:21179-1, SUSE-SU-2025:21139-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.6.1.160000.2.4 | SUSE-SU-2025:21139-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.6.1.160000.2.4 | SUSE-SU-2025:21074-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.6.1 | SUSE-SU-2026:20560-1, SUSE-SU-2025:21074-1 |
| SLE Micro 6.1 | kernel-default-base | 6.4.0-36.1.21.13 | SUSE-SU-2025:21056-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-38.1 | SUSE-SU-2025:21064-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-36.1 | SUSE-SU-2025:21056-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-36.1.21.13 | SUSE-SU-2025:21040-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-38.1 | SUSE-SU-2025:21052-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-36.1 | SUSE-SU-2025:21040-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.22.1 | SUSE-SU-2025:4057-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_6 | 1-150700.1.3.1 | SUSE-SU-2025:4141-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_6 | 1-150700.15.3.1 | SUSE-SU-2025:4057-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.78.1 | SUSE-SU-2025:4140-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6-RT_Update_17 | 1-150600.1.3.1 | SUSE-SU-2025:4301-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_17 | 1-150600.13.5.1 | SUSE-SU-2025:4140-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.22.1 | SUSE-SU-2025:4141-1 |
| SUSE Real Time Module 15 SP6 | kernel-rt +3 | 6.4.0-150600.10.58.1 | SUSE-SU-2025:4301-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.6.1.160000.2.4 | openSUSE-SU-2025:20081-1 |
| openSUSE Leap 16.0 | kernel-rt +10 | 6.12.0-160000.6.1 | openSUSE-SU-2025:20081-1 |
| openSUSE Leap 15.6 | dtb-aarch64 +10 | 6.4.0-150600.23.78.1 | SUSE-SU-2025:4140-1 |
| openSUSE Leap 15.6 | kernel-azure +2 | 6.4.0-150600.8.55.1 | SUSE-SU-2025:4128-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.78.1.150600.12.34.2 | SUSE-SU-2025:4140-1 |
| openSUSE Leap 15.6 | kernel-rt +3 | 6.4.0-150600.10.58.1 | SUSE-SU-2025:4301-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | bpftool +14 | 6.12.30-34.92.amzn2023 | ALAS2023-2025-1053 |
| Amazon Linux 2023 | kernel-livepatch-6.12.30-34.92 | 1.0-0.amzn2023 | ALAS2023-2025-1053 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-101.33.4.3.el10uek | ELSA-2025-20530, ELSA-2025-20480 |
Advisories 38
- WID-SEC-2025-1350 Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 12, 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-7699-2 linux-hwe-6.14, linux-oem-6.14 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7699-1 linux, linux-aws, linux-aws-6.14, linux-gcp, linux-gcp-6.14, linux-oracle, linux-oracle-6.14, linux-raspi, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- SUSE-SU-2026:20560-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- openSUSE-SU-2025:20081-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:4140-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:21179-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:21139-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:21074-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:21056-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:4141-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:21064-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:21040-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:21052-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:4128-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- USN-7721-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Feb 4, 2026
- SUSE-SU-2025:4132-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:4057-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:4301-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- ELSA-2025-20530 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Aug 18, 2025
- ALAS2023-2025-1053 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jul 29, 2025
- ELSA-2025-20480 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 17, 2025