powerpc/perf: fix preempt count underflow in fsl_emb_pmu_del
Summary
| CVE | CVE-2026-80626 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-28 08:16:46 UTC |
| Updated | 2026-08-28 08:16:46 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: powerpc/perf: fix preempt count underflow in fsl_emb_pmu_del fsl_emb_pmu_del() unconditionally calls put_cpu_var(cpu_hw_events) at the 'out:' label, but only calls the matching get_cpu_var() after the 'i < 0' early-return check. When event->hw.idx is negative the function jumps to 'out:' without having taken get_cpu_var(), and the trailing put_cpu_var() then issues an unmatched preempt_enable(), underflowing preempt_count. On a CONFIG_PREEMPT=y kernel preempt_count would underflow and eventually present as a 'scheduling while atomic' BUG. Move put_cpu_var() to pair with get_cpu_var() so the percpu access is correctly bracketed and the 'out:' label only handles perf_pmu_enable. |
Risk And Classification
EPSS: 0.001760000 probability, percentile 0.072550000 (date 2026-08-30)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected a11106544f33c104706ae42d27219a409b67478e c0c7722308c5f303117d8bd555290fdf26b098da git | Not specified |
| CNA | Linux | Linux | affected a11106544f33c104706ae42d27219a409b67478e 67aeb1eb93d4ffd898a3e74a7f3fe46ee71feb28 git | Not specified |
| CNA | Linux | Linux | affected a11106544f33c104706ae42d27219a409b67478e 9a515e00b00132b6fc3f1dd62dc5204bbda8cb10 git | Not specified |
| CNA | Linux | Linux | affected a11106544f33c104706ae42d27219a409b67478e 5397142d60aa29dcf636f5459d960bfc4f97c42a git | Not specified |
| CNA | Linux | Linux | affected a11106544f33c104706ae42d27219a409b67478e b89477077c834d94381c7bf07d81193bebefcff9 git | Not specified |
| CNA | Linux | Linux | affected a11106544f33c104706ae42d27219a409b67478e 73711688479df333acc134e3730fff1acba1843e git | Not specified |
| CNA | Linux | Linux | affected a11106544f33c104706ae42d27219a409b67478e b504fd953664c3f4d176ae8cb594adb3fda9d577 git | Not specified |
| CNA | Linux | Linux | affected a11106544f33c104706ae42d27219a409b67478e 81e3a86030462824a67d697739cf3f387f4ba350 git | Not specified |
| CNA | Linux | Linux | affected 2.6.34 | Not specified |
| CNA | Linux | Linux | unaffected 2.6.34 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.261 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.212 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.178 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.145 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.97 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.40 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.5 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/67aeb1eb93d4ffd898a3e74a7f3fe46ee71feb28 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/5397142d60aa29dcf636f5459d960bfc4f97c42a | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/b504fd953664c3f4d176ae8cb594adb3fda9d577 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/b89477077c834d94381c7bf07d81193bebefcff9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/9a515e00b00132b6fc3f1dd62dc5204bbda8cb10 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/73711688479df333acc134e3730fff1acba1843e | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/81e3a86030462824a67d697739cf3f387f4ba350 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c0c7722308c5f303117d8bd555290fdf26b098da | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.