{"id":"CVE-2026-80626","state":"PUBLISHED","title":"powerpc/perf: fix preempt count underflow in fsl_emb_pmu_del","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/perf: fix preempt count underflow in fsl_emb_pmu_del\n\nfsl_emb_pmu_del() unconditionally calls put_cpu_var(cpu_hw_events) at\nthe 'out:' label, but only calls the matching get_cpu_var() after the\n'i < 0' early-return check. When event->hw.idx is negative the\nfunction jumps to 'out:' without having taken get_cpu_var(), and the\ntrailing put_cpu_var() then issues an unmatched preempt_enable(),\nunderflowing preempt_count.\n\nOn a CONFIG_PREEMPT=y kernel preempt_count would underflow and\neventually present as a 'scheduling while atomic' BUG.\n\nMove put_cpu_var() to pair with get_cpu_var() so the percpu access is\ncorrectly bracketed and the 'out:' label only handles perf_pmu_enable.","publishedAt":"2026-08-28T06:48:44.182Z","updatedAt":"2026-08-28T06:48:44.182Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"c0c7722308c5f303117d8bd555290fdf26b098da","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"67aeb1eb93d4ffd898a3e74a7f3fe46ee71feb28","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"9a515e00b00132b6fc3f1dd62dc5204bbda8cb10","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"5397142d60aa29dcf636f5459d960bfc4f97c42a","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"b89477077c834d94381c7bf07d81193bebefcff9","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"73711688479df333acc134e3730fff1acba1843e","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"b504fd953664c3f4d176ae8cb594adb3fda9d577","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"81e3a86030462824a67d697739cf3f387f4ba350","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/powerpc/perf/core-fsl-emb.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.34","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.34","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/powerpc/perf/core-fsl-emb.c"]}],"references":["https://git.kernel.org/stable/c/c0c7722308c5f303117d8bd555290fdf26b098da","https://git.kernel.org/stable/c/67aeb1eb93d4ffd898a3e74a7f3fe46ee71feb28","https://git.kernel.org/stable/c/9a515e00b00132b6fc3f1dd62dc5204bbda8cb10","https://git.kernel.org/stable/c/5397142d60aa29dcf636f5459d960bfc4f97c42a","https://git.kernel.org/stable/c/b89477077c834d94381c7bf07d81193bebefcff9","https://git.kernel.org/stable/c/73711688479df333acc134e3730fff1acba1843e","https://git.kernel.org/stable/c/b504fd953664c3f4d176ae8cb594adb3fda9d577","https://git.kernel.org/stable/c/81e3a86030462824a67d697739cf3f387f4ba350"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80626.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80626","state":"PUBLISHED","datePublished":"2026-08-28T06:48:44.182Z","dateUpdated":"2026-08-28T06:48:44.182Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-26T14:34:25.775Z"},"containers":{"cna":{"title":"powerpc/perf: fix preempt count underflow in fsl_emb_pmu_del","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/perf: fix preempt count underflow in fsl_emb_pmu_del\n\nfsl_emb_pmu_del() unconditionally calls put_cpu_var(cpu_hw_events) at\nthe 'out:' label, but only calls the matching get_cpu_var() after the\n'i < 0' early-return check. When event->hw.idx is negative the\nfunction jumps to 'out:' without having taken get_cpu_var(), and the\ntrailing put_cpu_var() then issues an unmatched preempt_enable(),\nunderflowing preempt_count.\n\nOn a CONFIG_PREEMPT=y kernel preempt_count would underflow and\neventually present as a 'scheduling while atomic' BUG.\n\nMove put_cpu_var() to pair with get_cpu_var() so the percpu access is\ncorrectly bracketed and the 'out:' label only handles perf_pmu_enable."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"c0c7722308c5f303117d8bd555290fdf26b098da","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"67aeb1eb93d4ffd898a3e74a7f3fe46ee71feb28","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"9a515e00b00132b6fc3f1dd62dc5204bbda8cb10","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"5397142d60aa29dcf636f5459d960bfc4f97c42a","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"b89477077c834d94381c7bf07d81193bebefcff9","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"73711688479df333acc134e3730fff1acba1843e","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"b504fd953664c3f4d176ae8cb594adb3fda9d577","versionType":"git"},{"version":"a11106544f33c104706ae42d27219a409b67478e","status":"affected","lessThan":"81e3a86030462824a67d697739cf3f387f4ba350","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/powerpc/perf/core-fsl-emb.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.34","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.34","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/powerpc/perf/core-fsl-emb.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/c0c7722308c5f303117d8bd555290fdf26b098da"},{"url":"https://git.kernel.org/stable/c/67aeb1eb93d4ffd898a3e74a7f3fe46ee71feb28"},{"url":"https://git.kernel.org/stable/c/9a515e00b00132b6fc3f1dd62dc5204bbda8cb10"},{"url":"https://git.kernel.org/stable/c/5397142d60aa29dcf636f5459d960bfc4f97c42a"},{"url":"https://git.kernel.org/stable/c/b89477077c834d94381c7bf07d81193bebefcff9"},{"url":"https://git.kernel.org/stable/c/73711688479df333acc134e3730fff1acba1843e"},{"url":"https://git.kernel.org/stable/c/b504fd953664c3f4d176ae8cb594adb3fda9d577"},{"url":"https://git.kernel.org/stable/c/81e3a86030462824a67d697739cf3f387f4ba350"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-28T06:48:44.182Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.34","versionEndExcluding":"5.10.261"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.34","versionEndExcluding":"5.15.212"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.34","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.34","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.34","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.34","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.34","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.34","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}