{"dataType": "CVE_RECORD", "dataVersion": "5.1", "cveMetadata": {"cveId": "CVE-2025-21895", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-12-29T08:45:45.783Z", "datePublished": "2025-04-01T15:26:48.607Z", "dateUpdated": "2025-05-04T07:23:42.762Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2025-05-04T07:23:42.762Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Order the PMU list to fix warning about unordered pmu_ctx_list\n\nSyskaller triggers a warning due to prev_epc->pmu != next_epc->pmu in\nperf_event_swap_task_ctx_data(). vmcore shows that two lists have the same\nperf_event_pmu_context, but not in the same order.\n\nThe problem is that the order of pmu_ctx_list for the parent is impacted by\nthe time when an event/PMU is added. While the order for a child is\nimpacted by the event order in the pinned_groups and flexible_groups. So\nthe order of pmu_ctx_list in the parent and child may be different.\n\nTo fix this problem, insert the perf_event_pmu_context to its proper place\nafter iteration of the pmu_ctx_list.\n\nThe follow testcase can trigger above warning:\n\n # perf record -e cycles --call-graph lbr -- taskset -c 3 ./a.out &\n # perf stat -e cpu-clock,cs -p xxx // xxx is the pid of a.out\n\n test.c\n\n void main() {\n int count = 0;\n pid_t pid;\n\n printf(\"%d running\\n\", getpid());\n sleep(30);\n printf(\"running\\n\");\n\n pid = fork();\n if (pid == -1) {\n printf(\"fork error\\n\");\n return;\n }\n if (pid == 0) {\n while (1) {\n count++;\n }\n } else {\n while (1) {\n count++;\n }\n }\n }\n\nThe testcase first opens an LBR event, so it will allocate task_ctx_data,\nand then open tracepoint and software events, so the parent context will\nhave 3 different perf_event_pmu_contexts. On inheritance, child ctx will\ninsert the perf_event_pmu_context in another order and the warning will\ntrigger.\n\n[ mingo: Tidied up the changelog. ]"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/events/core.c"], "versions": [{"version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "f0c3971405cef6892844016aa710121a02da3a23", "status": "affected", "versionType": "git"}, {"version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "7d582eb6e4e100959ba07083d7563453c8c2a343", "status": "affected", "versionType": "git"}, {"version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "3e812a70732d84b7873cea61a7f6349b9a9dcbf5", "status": "affected", "versionType": "git"}, {"version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "2016066c66192a99d9e0ebf433789c490a6785a2", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/events/core.c"], "versions": [{"version": "6.2", "status": "affected"}, {"version": "0", "lessThan": "6.2", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.81", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.18", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.13.6", "lessThanOrEqual": "6.13.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.14", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.81"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.12.18"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.13.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.14"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/f0c3971405cef6892844016aa710121a02da3a23"}, {"url": "https://git.kernel.org/stable/c/7d582eb6e4e100959ba07083d7563453c8c2a343"}, {"url": "https://git.kernel.org/stable/c/3e812a70732d84b7873cea61a7f6349b9a9dcbf5"}, {"url": "https://git.kernel.org/stable/c/2016066c66192a99d9e0ebf433789c490a6785a2"}], "title": "perf/core: Order the PMU list to fix warning about unordered pmu_ctx_list", "x_generator": {"engine": "bippy-1.2.0"}}}}

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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "8C92C9CD-2ADE-412E-A7FF-DC9E0630B25D", "versionEndExcluding": "6.6.81", "versionStartIncluding": "6.2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "3D5C8D9A-4013-4C1A-810F-AA540BB5737C", "versionEndExcluding": "6.12.18", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "64F12D9B-71C2-4CD7-A288-0D5EF1709620", "versionEndExcluding": "6.13.6", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*", "matchCriteriaId": "186716B6-2B66-4BD0-852E-D48E71C0C85F", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*", "matchCriteriaId": "0D3E781C-403A-498F-9DA9-ECEE50F41E75", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*", "matchCriteriaId": "66619FB8-0AAF-4166-B2CF-67B24143261D", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*", "matchCriteriaId": "D3D6550E-6679-4560-902D-AF52DCFE905B", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Order the PMU list to fix warning about unordered pmu_ctx_list\n\nSyskaller triggers a warning due to prev_epc->pmu != next_epc->pmu in\nperf_event_swap_task_ctx_data(). vmcore shows that two lists have the same\nperf_event_pmu_context, but not in the same order.\n\nThe problem is that the order of pmu_ctx_list for the parent is impacted by\nthe time when an event/PMU is added. While the order for a child is\nimpacted by the event order in the pinned_groups and flexible_groups. So\nthe order of pmu_ctx_list in the parent and child may be different.\n\nTo fix this problem, insert the perf_event_pmu_context to its proper place\nafter iteration of the pmu_ctx_list.\n\nThe follow testcase can trigger above warning:\n\n # perf record -e cycles --call-graph lbr -- taskset -c 3 ./a.out &\n # perf stat -e cpu-clock,cs -p xxx // xxx is the pid of a.out\n\n test.c\n\n void main() {\n int count = 0;\n pid_t pid;\n\n printf(\"%d running\\n\", getpid());\n sleep(30);\n printf(\"running\\n\");\n\n pid = fork();\n if (pid == -1) {\n printf(\"fork error\\n\");\n return;\n }\n if (pid == 0) {\n while (1) {\n count++;\n }\n } else {\n while (1) {\n count++;\n }\n }\n }\n\nThe testcase first opens an LBR event, so it will allocate task_ctx_data,\nand then open tracepoint and software events, so the parent context will\nhave 3 different perf_event_pmu_contexts. On inheritance, child ctx will\ninsert the perf_event_pmu_context in another order and the warning will\ntrigger.\n\n[ mingo: Tidied up the changelog. ]"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: perf/core: Ordenar la lista de PMU para corregir la advertencia sobre pmu_ctx_list desordenada Syskaller activa una advertencia debido a prev_epc->pmu != next_epc->pmu en perf_event_swap_task_ctx_data(). vmcore muestra que dos listas tienen el mismo perf_event_pmu_context, pero no en el mismo orden. El problema es que el orden de pmu_ctx_list para el padre se ve afectado por el momento en que se agrega un evento/PMU. Mientras que el orden para un hijo se ve afectado por el orden de los eventos en pinned_groups y flexible_groups. Por lo tanto, el orden de pmu_ctx_list en el padre y el hijo puede ser diferente. Para corregir este problema, inserte perf_event_pmu_context en su lugar correcto despu\u00e9s de la iteraci\u00f3n de pmu_ctx_list. El siguiente caso de prueba puede activar la advertencia anterior: # perf record -e cycles --call-graph lbr -- tasket -c 3 ./a.out & # perf stat -e cpu-clock,cs -p xxx // xxx es el pid de a.out test.c void main() { int count = 0; pid_t pid; printf(\"%d en ejecuci\u00f3n\\n\", getpid()); sleep(30); printf(\"en ejecuci\u00f3n\\n\"); pid = fork(); if (pid == -1) { printf(\"fork error\\n\"); return; } if (pid == 0) { while (1) { count++; } } else { while (1) { count++; } } } El caso de prueba primero abre un evento LBR, por lo que asignar\u00e1 task_ctx_data y luego abrir\u00e1 los eventos de tracepoint y software, por lo que el contexto principal tendr\u00e1 3 perf_event_pmu_contexts diferentes. En caso de herencia, el ctx secundario insertar\u00e1 perf_event_pmu_context en otro orden y se activar\u00e1 la advertencia. [mingo: Se orden\u00f3 el registro de cambios.]"}], "id": "CVE-2025-21895", "lastModified": "2025-10-31T18:50:50.357", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 4.7, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.0, "impactScore": 3.6, "source": "[email protected]", "type": "Primary"}]}, "published": "2025-04-01T16:15:19.883", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2016066c66192a99d9e0ebf433789c490a6785a2"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/3e812a70732d84b7873cea61a7f6349b9a9dcbf5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/7d582eb6e4e100959ba07083d7563453c8c2a343"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f0c3971405cef6892844016aa710121a02da3a23"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-362"}], "source": "[email protected]", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: perf/core: Order the PMU list to fix warning about unordered pmu_ctx_list", "id": "2356614", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2356614"}, "csaw": false, "cvss3": {"cvss3_base_score": "2.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-362", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nperf/core: Order the PMU list to fix warning about unordered pmu_ctx_list\nSyskaller triggers a warning due to prev_epc->pmu != next_epc->pmu in\nperf_event_swap_task_ctx_data(). vmcore shows that two lists have the same\nperf_event_pmu_context, but not in the same order.\nThe problem is that the order of pmu_ctx_list for the parent is impacted by\nthe time when an event/PMU is added. While the order for a child is\nimpacted by the event order in the pinned_groups and flexible_groups. So\nthe order of pmu_ctx_list in the parent and child may be different.\nTo fix this problem, insert the perf_event_pmu_context to its proper place\nafter iteration of the pmu_ctx_list.\nThe follow testcase can trigger above warning:\n# perf record -e cycles --call-graph lbr -- taskset -c 3 ./a.out &\n# perf stat -e cpu-clock,cs -p xxx // xxx is the pid of a.out\ntest.c\nvoid main() {\nint count = 0;\npid_t pid;\nprintf(\"%d running\\n\", getpid());\nsleep(30);\nprintf(\"running\\n\");\npid = fork();\nif (pid == -1) {\nprintf(\"fork error\\n\");\nreturn;\n}\nif (pid == 0) {\nwhile (1) {\ncount++;\n}\n} else {\nwhile (1) {\ncount++;\n}\n}\n}\nThe testcase first opens an LBR event, so it will allocate task_ctx_data,\nand then open tracepoint and software events, so the parent context will\nhave 3 different perf_event_pmu_contexts. On inheritance, child ctx will\ninsert the perf_event_pmu_context in another order and the warning will\ntrigger.\n[ mingo: Tidied up the changelog. ]"], "name": "CVE-2025-21895", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-04-01T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-21895\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-21895\nhttps://lore.kernel.org/linux-cve-announce/2025040132-CVE-2025-21895-5c1a@gregkh/T"], "threat_severity": "Low"}