Description
In the Linux kernel, the following vulnerability has been resolved:
sched/deadline: Fix task_struct reference leak
During the execution of the following stress test with linux-rt:
stress-ng --cyclic 30 --timeout 30 --minimize --quiet
kmemleak frequently reported a memory leak concerning the task_struct:
unreferenced object 0xffff8881305b8000 (size 16136):
comm "stress-ng", pid 614, jiffies 4294883961 (age 286.412s)
object hex dump (first 32 bytes):
02 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 .@..............
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
debug hex dump (first 16 bytes):
53 09 00 00 00 00 00 00 00 00 00 00 00 00 00 00 S...............
backtrace:
[<00000000046b6790>] dup_task_struct+0x30/0x540
[<00000000c5ca0f0b>] copy_process+0x3d9/0x50e0
[<00000000ced59777>] kernel_clone+0xb0/0x770
[<00000000a50befdc>] __do_sys_clone+0xb6/0xf0
[<000000001dbf2008>] do_syscall_64+0x5d/0xf0
[<00000000552900ff>] entry_SYSCALL_64_after_hwframe+0x6e/0x76
The issue occurs in start_dl_timer(), which increments the task_struct
reference count and sets a timer. The timer callback, dl_task_timer,
is supposed to decrement the reference count upon expiration. However,
if enqueue_task_dl() is called before the timer expires and cancels it,
the reference count is not decremented, leading to the leak.
This patch fixes the reference leak by ensuring the task_struct
reference count is properly decremented when the timer is canceled.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 4.19.257 – < 4.20, 5.4.212 – < 5.5, 5.10 | 4.20 |
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 | 6.9.10-1 | — |
| Debian 13 | linux | 6.9.10-1 | — |
| Debian 12 | linux | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | No fix yet | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-48.48 | USN-7089-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1018.20 | USN-7089-3 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1017.20 | USN-7089-2 |
| Ubuntu 24.04 LTS | linux-gcp +1 | 6.8.0-1017.19 | USN-7095-1, USN-7089-2 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1013.17 | USN-7089-6 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1002.4 | USN-7156-1 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1015.15 | USN-7089-2 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-48.48.3 | USN-7089-7 |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1017.19.1 | USN-7095-1 |
| Ubuntu 24.04 LTS | linux-oem-6.8 | 6.8.0-1016.16 | USN-7089-4 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1015.16 | USN-7089-3 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1014.16 | USN-7089-5 |
| Ubuntu 24.04 LTS | linux-riscv | 6.8.0-48.48.1 | — |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1009.10 | — |
| Ubuntu 22.04 LTS | linux +49 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1018.19~22.04.1 | USN-7089-3 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1017.20~22.04.1 | USN-7090-1 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 +1 | 6.8.0-1017.19~22.04.1 | USN-7095-1, USN-7089-1 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 | 6.8.0-48.48~22.04.1 | USN-7089-1 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 +1 | 6.8.0-1015.15~22.04.1 | USN-7089-3 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-48.48.3~22.04.1 | USN-7089-7 |
| Ubuntu 22.04 LTS | linux-riscv-6.8 | 6.8.0-48.48.1~22.04.2 | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +13 | No fix yet | — |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2013.14 | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1011.11 | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime +1 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1011.11~22.04.1 | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-78.78+fips1 | — |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips +3 | No fix yet | — |
| 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 +21 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | linux-aws-5.4 +6 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | perf +26 | 4.18.0-553.22.1.el8_10 | RHSA-2024:7000 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.4 EUS | bpftool | 7.3.0-427.44.1.el9_4 | RHSA-2024:9546 |
| RHEL 9.4 EUS | rv +64 | 5.14.0-427.44.1.el9_4 | RHSA-2024:9546 |
| RHEL 9.2 EUS | bpftool | 7.0.0-284.84.1.el9_2 | RHSA-2024:6744 |
| RHEL 9.2 EUS | kernel-rt +14 | 5.14.0-284.84.1.rt14.369.el9_2 | RHSA-2024:6745 |
| RHEL 9.2 EUS | perf +47 | 5.14.0-284.84.1.el9_2 | RHSA-2024:6744 |
| RHEL 8.8 EUS | perf +26 | 4.18.0-477.81.1.el8_8 | RHSA-2024:10262 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | perf +24 | 4.18.0-553.22.1.el8_10 | ALSA-2024:7000 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | kernel | 4.18.0-553.22.1.el8_10 | RLSA-2024:7000 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.30.1 | SUSE-SU-2024:4318-1 |
| SLES 15 SP6 | kernel-azure +2 | 6.4.0-150600.8.20.1 | SUSE-SU-2024:4316-1 |
| SLES 15 SP6 | kernel-coco +3 | 6.4.0-15061.9.coco15sp6.1 | SUSE-SU-2024:4387-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.30.1.150600.12.12.6 | SUSE-SU-2024:4318-1 |
| SLES 15 SP5 | kernel-64kb +6 | 5.14.21-150500.55.88.1 | SUSE-SU-2024:4364-1 |
| SLES 15 SP5 | kernel-azure +2 | 5.14.21-150500.33.75.1 | SUSE-SU-2024:4376-1 |
| SLES 15 SP5 | kernel-default-base | 5.14.21-150500.55.88.1.150500.6.39.4 | SUSE-SU-2024:4364-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 6.1 | kernel-default-base | 6.4.0-24.1.21.4 | SUSE-SU-2025:20247-1 |
| SLE Micro 6.1 | kernel-livepatch-MICRO-6-0-RT_Update_4 | 1-1.1 | SUSE-SU-2025:20246-1 |
| SLE Micro 6.1 | kernel-livepatch-MICRO-6-0_Update_4 | 1-1.2 | SUSE-SU-2025:20247-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-22.1 | SUSE-SU-2025:20246-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-24.1 | SUSE-SU-2025:20247-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-24.1.21.4 | SUSE-SU-2025:20164-1 |
| SLE Micro 6.0 | kernel-livepatch-MICRO-6-0-RT_Update_4 | 1-1.1 | SUSE-SU-2025:20163-1 |
| SLE Micro 6.0 | kernel-livepatch-MICRO-6-0_Update_4 | 1-1.2 | SUSE-SU-2025:20164-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-22.1 | SUSE-SU-2025:20163-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-24.1 | SUSE-SU-2025:20164-1 |
| SLE Micro 5.5 | kernel-default | 5.14.21-150500.55.88.1 | SUSE-SU-2024:4364-1 |
| SLE Micro 5.5 | kernel-default-base | 5.14.21-150500.55.88.1.150500.6.39.4 | SUSE-SU-2024:4364-1 |
| SLE Micro 5.5 | kernel-rt +1 | 5.14.21-150500.13.79.1 | SUSE-SU-2024:4315-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.30.1 | SUSE-SU-2024:4318-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6-RT_Update_6 | 1-150600.1.3.1 | SUSE-SU-2024:4314-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_6 | 1-150600.13.3.5 | SUSE-SU-2024:4318-1 |
| SLE Live Patching 15 SP5 | kernel-default | 5.14.21-150500.55.88.1 | SUSE-SU-2024:4364-1 |
| SLE Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5-RT_Update_23 | 1-150500.11.3.1 | SUSE-SU-2024:4315-1 |
| SLE Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5_Update_21 | 1-150500.11.5.1 | SUSE-SU-2024:4364-1 |
| SUSE Real Time Module 15 SP6 | kernel-rt +3 | 6.4.0-150600.10.20.1 | SUSE-SU-2024:4314-1 |
| SUSE Real Time Module 15 SP5 | kernel-rt +3 | 5.14.21-150500.13.79.1 | SUSE-SU-2024:4315-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.6 | dtb-aarch64 +10 | 6.4.0-150600.23.30.1 | SUSE-SU-2024:4318-1 |
| openSUSE Leap 15.6 | kernel-azure +2 | 6.4.0-150600.8.20.1 | SUSE-SU-2024:4316-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.30.1.150600.12.12.6 | SUSE-SU-2024:4318-1 |
| openSUSE Leap 15.6 | kernel-rt +3 | 6.4.0-150600.10.20.1 | SUSE-SU-2024:4314-1 |
| openSUSE Leap 15.5 | kernel-azure +2 | 5.14.21-150500.33.75.1 | SUSE-SU-2024:4376-1 |
| openSUSE Leap 15.5 | kernel-rt +3 | 5.14.21-150500.13.79.1 | SUSE-SU-2024:4315-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap Micro 5.5 | kernel-rt | 5.14.21-150500.13.79.1 | SUSE-SU-2024:4315-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | No fix yet | — |
| Azure Linux 2 (CBL-Mariner) | kernel | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | perf +19 | 4.18.0-553.22.1.el8_10 | ELSA-2024-7000 |
Advisories 30
- WID-SEC-2024-1722 Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff BSI CERT-Bund (WID) · Nov 9, 2026
- USN-7156-1 linux-gkeop vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7095-1 linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- USN-7090-1 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 29, 2026
- ALSA-2024:7000 Important: kernel security update AlmaLinux Security Advisories · Oct 29, 2026
- USN-7089-6 linux-gke vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-7089-3 linux-aws, linux-aws-6.8, linux-oracle, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-7089-7 linux-lowlatency, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-7089-2 linux-azure, linux-gcp, linux-ibm vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-7089-1 linux, linux-gcp-6.8, linux-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-7089-5 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- USN-7089-4 linux-oem-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 26, 2026
- RHSA-2024:7000 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Oct 17, 2026
- RHSA-2024:10262 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Oct 17, 2026
- RHSA-2024:9546 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Oct 15, 2026
- RHSA-2024:6744 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Aug 20, 2026
- RHSA-2024:6745 Red Hat Security Advisory: kernel-rt security update Red Hat Security Advisories (RHSA) · Aug 20, 2026
- SUSE-SU-2025:20163-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20246-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20164-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20247-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2024:4376-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4318-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4364-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4316-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4315-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4387-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:4314-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- RLSA-2024:7000 Important: kernel security update Rocky Linux Security Advisories · May 7, 2025
- ELSA-2024-7000 Important: kernel security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Sep 24, 2024