Description
In the Linux kernel, the following vulnerability has been resolved:
futex: Prevent use-after-free during requeue-PI
syzbot managed to trigger the following race:
T1 T2
futex_wait_requeue_pi()
futex_do_wait()
schedule()
futex_requeue()
futex_proxy_trylock_atomic()
futex_requeue_pi_prepare()
requeue_pi_wake_futex()
futex_requeue_pi_complete()
/* preempt */
* timeout/ signal wakes T1 *
futex_requeue_pi_wakeup_sync() // Q_REQUEUE_PI_LOCKED
futex_hash_put()
// back to userland, on stack futex_q is garbage
/* back */
wake_up_state(q->task, TASK_NORMAL);
In this scenario futex_wait_requeue_pi() is able to leave without using
futex_q::lock_ptr for synchronization.
This can be prevented by reading futex_q::task before updating the
futex_q::requeue_state. A reference on the task_struct is not needed
because requeue_pi_wake_futex() is invoked with a spinlock_t held which
implies a RCU read section.
Even if T1 terminates immediately after, the task_struct will remain valid
during T2's wake_up_state(). A READ_ONCE on futex_q::task before
futex_requeue_pi_complete() is enough because it ensures that the variable
is read before the state is updated.
Read futex_q::task before updating the requeue state, use it for the
following wakeup.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.15 | 6.1.155 |
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 | 6.16.10-1 | — |
| Debian 13 | linux | 6.12.57-1 | — |
| Debian 12 | linux | 6.1.158-1 | DSA-6053-1 |
| Debian 11 | linux-6.1 | 6.1.158-1~deb11u1 | DLA-4379-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1017.21 | — |
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | No fix yet | — |
| Ubuntu 25.10 | linux | 6.17.0-6.6 | — |
| Ubuntu 25.10 | linux-aws +2 | 6.17.0-1003.3 | — |
| Ubuntu 25.10 | linux-azure | 6.17.0-1006.6 | — |
| Ubuntu 25.10 | linux-azure-fde | No fix yet | — |
| Ubuntu 25.10 | linux-raspi | 6.17.0-1004.4 | — |
| Ubuntu 25.10 | linux-realtime | 6.17.0-1002.3 | — |
| Ubuntu 25.10 | linux-riscv | 6.17.0-6.6.1 | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-106.106 | USN-8095-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1050.53 | USN-8095-1 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1051.57 | USN-8125-1 |
| Ubuntu 24.04 LTS | linux-azure-fde | 6.8.0-1058.65 | — |
| Ubuntu 24.04 LTS | linux-azure-nvidia | 6.8.0-1039.42 | — |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1052.55 | USN-8095-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1048.53 | USN-8095-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1035.38 | USN-8095-1 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1049.49 | USN-8095-1 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-106.106.1 | USN-8095-1 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1049.52 | USN-8100-1 |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1049.52.1 | USN-8100-1 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1020.20 | — |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1047.48 | USN-8095-1 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1050.54 | USN-8095-5 |
| Ubuntu 24.04 LTS | linux-riscv +18 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1028.29 | USN-8261-1 |
| Ubuntu 22.04 LTS | linux +49 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1050.53~22.04.1 | USN-8095-4 |
| 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 | 6.8.0-1058.65~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1052.55~22.04.1 | USN-8095-1 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 +1 | 6.8.0-106.106~22.04.1 | USN-8095-1 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1049.49~22.04.1 | USN-8095-1 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-106.106.1~22.04.1 | USN-8095-1 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1049.52~22.04.1 | USN-8100-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1047.48~22.04.1 | USN-8095-1 |
Show 9 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 | 6.8.0-2040.41 | USN-8095-5 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1045.46 | USN-8095-3 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime +1 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1045.46~22.04.1 | USN-8095-3 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1050.53+fips1 | USN-8095-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1052.58+fips1 | USN-8165-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-106.106+fips1 | USN-8095-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1052.55+fips1 | USN-8095-2 |
| Ubuntu Pro FIPS-updates 22.04 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-aws-5.15 +10 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +6 | 6.4.0-150700.53.28.1 | SUSE-SU-2026:0315-1 |
| SLES 15 SP7 | kernel-azure +2 | 6.4.0-150700.20.24.1 | SUSE-SU-2026:0281-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.28.1.150700.17.19.1 | SUSE-SU-2026:0315-1 |
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.84.1 | SUSE-SU-2026:0293-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.84.1.150600.12.38.1 | SUSE-SU-2026:0293-1 |
| SLES 15 SP5 | kernel-64kb +6 | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLES 15 SP5 | kernel-default-base | 5.14.21-150500.55.133.1.150500.6.65.1 | SUSE-SU-2026:0317-1 |
| SLES 15 SP4 | kernel-64kb +6 | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLES 15 SP4 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
Show 18 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.9.1 | SUSE-SU-2026:20220-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.9.1.160000.2.6 | SUSE-SU-2026:20220-1 |
| SLES for SAP 15 SP6 | kernel-default-base | 6.4.0-150600.23.84.1.150600.12.38.1 | SUSE-SU-2026:0293-1 |
| SLES for SAP 15 SP6 | kernel-docs +4 | 6.4.0-150600.23.84.1 | SUSE-SU-2026:0293-1 |
| SLES for SAP 15 SP5 | kernel-default-base | 5.14.21-150500.55.133.1.150500.6.65.1 | SUSE-SU-2026:0317-1 |
| SLES for SAP 15 SP5 | kernel-docs +4 | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLES for SAP 15 SP4 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
| SLES for SAP 15 SP4 | kernel-docs +4 | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.9.1 | SUSE-SU-2026:20228-1, SUSE-SU-2026:20220-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.9.1.160000.2.6 | SUSE-SU-2026:20220-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.9.1.160000.2.6 | SUSE-SU-2026:20207-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.9.1 | SUSE-SU-2026:20564-1, SUSE-SU-2026:20207-1 |
| SLE Micro 6.1 | kernel-default-base | 6.4.0-39.1.21.16 | SUSE-SU-2026:20498-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-40.1 | SUSE-SU-2026:20876-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-39.1 | SUSE-SU-2026:20498-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-39.1.21.16 | SUSE-SU-2026:20477-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-40.1 | SUSE-SU-2026:20845-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-39.1 | SUSE-SU-2026:20477-1 |
| SLE Micro 5.5 | kernel-default-base | 5.14.21-150500.55.133.1.150500.6.65.1 | SUSE-SU-2026:0317-1 |
| SLE Micro 5.5 | kernel-rt +1 | 5.14.21-150500.13.118.1 | SUSE-SU-2026:0263-1 |
| SLE Micro 5.5 | kernel-source +1 | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLE Micro 5.4 | kernel-default | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE Micro 5.4 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
| SLE Micro 5.4 | kernel-rt +1 | 5.14.21-150400.15.142.1 | SUSE-SU-2026:0411-1 |
| SLE Micro 5.3 | kernel-default | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE Micro 5.3 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
| SLE Micro 5.3 | kernel-rt +1 | 5.14.21-150400.15.142.1 | SUSE-SU-2026:0411-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.28.1 | SUSE-SU-2026:0315-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_8 | 1-150700.1.3.1 | SUSE-SU-2026:0278-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_8 | 1-150700.15.3.1 | SUSE-SU-2026:0315-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.84.1 | SUSE-SU-2026:0293-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_19 | 1-150600.13.3.1 | SUSE-SU-2026:0293-1 |
| SLE Live Patching 15 SP5 | kernel-default | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLE Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5_Update_34 | 1-150500.11.3.1 | SUSE-SU-2026:0317-1 |
| SLE Live Patching 15 SP4 | kernel-default | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE Live Patching 15 SP4 | kernel-livepatch-SLE15-SP4_Update_48 | 1-150400.9.7.1 | SUSE-SU-2026:0617-1 |
| SLE HPC 15 SP5 | kernel-64kb +5 | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLE HPC 15 SP5 | kernel-default-base | 5.14.21-150500.55.133.1.150500.6.65.1 | SUSE-SU-2026:0317-1 |
| SLE HPC 15 SP4 | kernel-64kb +5 | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE HPC 15 SP4 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.28.1 | SUSE-SU-2026:0278-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.9.1.160000.2.6 | openSUSE-SU-2026:20145-1 |
| openSUSE Leap 16.0 | kernel-rt +11 | 6.12.0-160000.9.1 | openSUSE-SU-2026:20145-1 |
| openSUSE Leap 15.6 | dtb-aarch64 +10 | 6.4.0-150600.23.84.1 | SUSE-SU-2026:0293-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.84.1.150600.12.38.1 | SUSE-SU-2026:0293-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.12.53-69.119 +1 | 1:1.0-0.amzn2023 | ALAS2023-2025-1254, ALAS2023-2025-1223 |
| Amazon Linux 2023 | perf +14 | 1:6.1.155-176.282.amzn2023 | ALAS2023-2025-1223 |
| Amazon Linux 2023 | perf6.12 +14 | 1:6.12.53-69.119.amzn2023 | ALAS2023-2025-1254 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.112.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-104.43.4.3.el10uek | ELSA-2025-20719 |
Advisories 39
- SSA-457936 SSA-457936: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.7 Siemens ProductCERT · Nov 10, 2026
- USN-8100-1 linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8165-1 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- WID-SEC-2025-2298 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 3, 2026
- USN-8095-1 linux, linux-aws, linux-gcp, linux-gcp-6.8, linux-gke, linux-gkeop, linux-hwe-6.8, linux-ibm, linux-ibm-6.8, linux-lowlatency, linux-lowlatency-hwe-6.8, linux-oracle, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8095-2 linux-fips, linux-aws-fips, linux-gcp-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8126-1 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8095-5 linux-raspi, linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8125-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8095-4 linux-aws-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8095-3 linux-realtime, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- ICSA-26-295-11 Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP CISA ICS & IT advisories · Oct 22, 2026
- SSA-019113 SSA-019113: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.6 Siemens ProductCERT · Oct 13, 2026
- SSA-082556 SSA-082556: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.5 Siemens ProductCERT · Oct 13, 2026
- USN-8261-1 linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Sep 7, 2026
- ICSA-26-209-04 Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP CISA ICS & IT advisories · Jul 28, 2026
- SUSE-SU-2026:20564-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- ICSA-25-162-05 Siemens SIMATIC S7-1500 CPU family CISA ICS & IT advisories · May 14, 2026
- SUSE-SU-2026:20876-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 31, 2026
- SUSE-SU-2026:20845-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 28, 2026
- openSUSE-SU-2026:20145-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20498-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20477-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20228-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20207-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20220-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0293-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0317-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0281-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0278-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0315-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0617-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 26, 2026
- SUSE-SU-2026:0411-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 10, 2026
- SUSE-SU-2026:0263-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- DLA-4379-1 linux-6.1 - security update Debian Security (DSA / DLA) · Nov 25, 2025
- DSA-6053-1 linux - security update Debian Security (DSA / DLA) · Nov 11, 2025
- ALAS2023-2025-1254 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 27, 2025
- ELSA-2025-20719 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 24, 2025
- ALAS2023-2025-1223 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 14, 2025
References
- https://git.kernel.org/stable/c/cb5d19a61274b51b49601214a87af573b43d60fa
- https://git.kernel.org/stable/c/348736955ed6ca6e99ca24b93b1d3fbfe352c181
- https://git.kernel.org/stable/c/a170b9c0dde83312b8b58ccc91509c7c15711641
- https://git.kernel.org/stable/c/d824b2dbdcfe3c390278dd9652ea526168ef6850
- https://git.kernel.org/stable/c/b549113738e8c751b613118032a724b772aa83f2