Description
In the Linux kernel, the following vulnerability has been resolved:
perf/core: Order the PMU list to fix warning about unordered pmu_ctx_list
Syskaller triggers a warning due to prev_epc->pmu != next_epc->pmu in
perf_event_swap_task_ctx_data(). vmcore shows that two lists have the same
perf_event_pmu_context, but not in the same order.
The problem is that the order of pmu_ctx_list for the parent is impacted by
the time when an event/PMU is added. While the order for a child is
impacted by the event order in the pinned_groups and flexible_groups. So
the order of pmu_ctx_list in the parent and child may be different.
To fix this problem, insert the perf_event_pmu_context to its proper place
after iteration of the pmu_ctx_list.
The follow testcase can trigger above warning:
# perf record -e cycles --call-graph lbr -- taskset -c 3 ./a.out &
# perf stat -e cpu-clock,cs -p xxx // xxx is the pid of a.out
test.c
void main() {
int count = 0;
pid_t pid;
printf("%d running\n", getpid());
sleep(30);
printf("running\n");
pid = fork();
if (pid == -1) {
printf("fork error\n");
return;
}
if (pid == 0) {
while (1) {
count++;
}
} else {
while (1) {
count++;
}
}
}
The testcase first opens an LBR event, so it will allocate task_ctx_data,
and then open tracepoint and software events, so the parent context will
have 3 different perf_event_pmu_contexts. On inheritance, child ctx will
insert the perf_event_pmu_context in another order and the warning will
trigger.
[ mingo: Tidied up the changelog. ]
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.2 | 6.6.81 |
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 | 6.12.19-1 | — |
| Debian 13 | linux | 6.12.19-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux | 6.8.0-84.84 | USN-7764-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1039.41 | USN-7764-1 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1038.44 | USN-7802-1 |
| Ubuntu 24.04 LTS | linux-azure-nvidia | 6.8.0-1025.27 | USN-7809-1 |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1040.42 | USN-7764-1 |
| Ubuntu 24.04 LTS | linux-gcp-6.11 +1 | 6.11.0-1015.15~24.04.1 | USN-7521-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1036.40 | USN-7764-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1023.25 | USN-7764-1 |
| Ubuntu 24.04 LTS | linux-hwe-6.11 | 6.11.0-26.26~24.04.1 | USN-7521-1 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1037.37 | USN-7779-1 |
| Ubuntu 24.04 LTS | linux-intel +4 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-84.84.1 | USN-7764-1 |
| Ubuntu 24.04 LTS | linux-lowlatency-hwe-6.11 | 6.11.0-1014.15~24.04.1 | USN-7521-3 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1039.42 | USN-7765-1 |
| Ubuntu 24.04 LTS | linux-nvidia-6.11 | 6.11.0-1010.10 | — |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1039.42.1 | USN-7765-1 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1010.10 | — |
| Ubuntu 24.04 LTS | linux-oem-6.11 | 6.11.0-1022.22 | USN-7521-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1037.38 | USN-7801-2 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1039.43 | USN-7790-1 |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1018.19 | — |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1039.41~22.04.1 | USN-7766-1 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1036.42~22.04.1 | USN-7802-1 |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1040.42~22.04.1 | USN-7766-1 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 | 6.8.0-85.85~22.04.1 | USN-7801-1, USN-7764-2 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1037.37~22.04.1 | USN-7779-1 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-84.84.1~22.04.1 | USN-7764-1 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1039.42~22.04.1 | USN-7765-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1037.38~22.04.1 | USN-7801-3 |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv-6.8 | 6.8.0-84.84~22.04.1 | — |
| 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 | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2030.31 | USN-7800-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1034.35 | USN-7767-1 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1034.35~22.04.1 | USN-7767-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1039.41+fips1 | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1040.46+fips1 | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-84.84+fips1 | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1040.42+fips1 | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +6 | 6.4.0-150700.53.3.1 | SUSE-SU-2025:01951-1 |
| SLES 15 SP7 | kernel-azure +2 | 6.4.0-150700.20.3.1 | SUSE-SU-2025:01967-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.3.1.150700.17.2.1 | SUSE-SU-2025:01951-1 |
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.50.1 | SUSE-SU-2025:01614-1 |
| SLES 15 SP6 | kernel-azure +2 | 6.4.0-150600.8.37.1 | SUSE-SU-2025:01707-1 |
| SLES 15 SP6 | kernel-coco +3 | 6.4.0-15061.21.coco15sp6.1 | SUSE-SU-2025:01919-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.50.1.150600.12.22.1 | SUSE-SU-2025:01614-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 6.1 | kernel-default-base | 6.4.0-28.1.21.6 | SUSE-SU-2025:20270-1 |
| SLE Micro 6.1 | kernel-livepatch-MICRO-6-0-RT_Update_7 | 1-1.3 | SUSE-SU-2025:20283-1 |
| SLE Micro 6.1 | kernel-livepatch-MICRO-6-0_Update_6 | 1-3.1 | SUSE-SU-2025:20270-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-30.1 | SUSE-SU-2025:20283-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-28.1 | SUSE-SU-2025:20270-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-28.1.21.6 | SUSE-SU-2025:20192-1 |
| SLE Micro 6.0 | kernel-livepatch-MICRO-6-0-RT_Update_7 | 1-1.3 | SUSE-SU-2025:20206-1 |
| SLE Micro 6.0 | kernel-livepatch-MICRO-6-0_Update_6 | 1-3.1 | SUSE-SU-2025:20192-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-30.1 | SUSE-SU-2025:20206-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-28.1 | SUSE-SU-2025:20192-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.3.1 | SUSE-SU-2025:01951-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_1 | 1-150700.15.3.1 | SUSE-SU-2025:01951-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.50.1 | SUSE-SU-2025:01614-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6-RT_Update_11 | 1-150600.1.3.2 | SUSE-SU-2025:01964-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_11 | 1-150600.13.3.1 | SUSE-SU-2025:01614-1 |
| SUSE Real Time Module 15 SP6 | kernel-rt +3 | 6.4.0-150600.10.39.1 | SUSE-SU-2025:01964-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.6 | dtb-aarch64 +10 | 6.4.0-150600.23.50.1 | SUSE-SU-2025:01614-1 |
| openSUSE Leap 15.6 | kernel-azure +2 | 6.4.0-150600.8.37.1 | SUSE-SU-2025:01707-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.50.1.150600.12.22.1 | SUSE-SU-2025:01614-1 |
| openSUSE Leap 15.6 | kernel-rt +3 | 6.4.0-150600.10.39.1 | SUSE-SU-2025:01964-1 |
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 29
- WID-SEC-2025-0683 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 10, 2026
- USN-7802-1 linux-azure, linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7809-1 linux-azure-nvidia vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7801-1 linux-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7801-3 linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7800-1 linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7801-2 linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7764-1 linux, linux-aws, linux-gcp, linux-gke, linux-gkeop, linux-lowlatency, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7765-1 linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7766-1 linux-aws-6.8, linux-gcp-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7767-2 linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7767-1 linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7779-1 linux-ibm, linux-ibm-6.8 vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7790-1 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7521-1 linux, linux-azure, linux-azure-6.11, linux-gcp, linux-gcp-6.11, linux-hwe-6.11, linux-oem-6.11, linux-raspi, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7521-3 linux-lowlatency, linux-lowlatency-hwe-6.11, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- USN-7764-2 linux-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- SUSE-SU-2025:20270-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20283-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20192-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20206-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:01614-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:01967-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:01919-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:01951-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:01964-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:01707-1 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
- ELSA-2025-20480 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 17, 2025