CVE-2025-37871

{"id": "CVE-2025-37871", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "[email protected]", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2025-05-09T07:16:08.210", "references": [{"url": "https://git.kernel.org/stable/c/14985d66b9b99c12995dd99d1c6c8dec4114c2a5", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/7d192e27a431026c58d60edf66dc6cd98d0c01fc", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/a1d14d931bf700c1025db8c46d6731aa5cf440f9", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/a70832d3555987035fc430ccd703acd89393eadb", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/a7fce086f6ca84db409b9d58493ea77c1978897c", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b9bbe8f9d5663311d06667ce36d6ed255ead1a26", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ba903539fff745d592d893c71b30e5e268a95413", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html", "tags": ["Mailing List", "Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html", "tags": ["Mailing List", "Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "[email protected]", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: decrease sc_count directly if fail to queue dl_recall\n\nA deadlock warning occurred when invoking nfs4_put_stid following a failed\ndl_recall queue operation:\n T1 T2\n nfs4_laundromat\n nfs4_get_client_reaplist\n nfs4_anylock_blockers\n__break_lease\n spin_lock // ctx->flc_lock\n spin_lock // clp->cl_lock\n nfs4_lockowner_has_blockers\n locks_owner_has_blockers\n spin_lock // flctx->flc_lock\n nfsd_break_deleg_cb\n nfsd_break_one_deleg\n nfs4_put_stid\n refcount_dec_and_lock\n spin_lock // clp->cl_lock\n\nWhen a file is opened, an nfs4_delegation is allocated with sc_count\ninitialized to 1, and the file_lease holds a reference to the delegation.\nThe file_lease is then associated with the file through kernel_setlease.\n\nThe disassociation is performed in nfsd4_delegreturn via the following\ncall chain:\nnfsd4_delegreturn --> destroy_delegation --> destroy_unhashed_deleg -->\nnfs4_unlock_deleg_lease --> kernel_setlease --> generic_delete_lease\nThe corresponding sc_count reference will be released after this\ndisassociation.\n\nSince nfsd_break_one_deleg executes while holding the flc_lock, the\ndisassociation process becomes blocked when attempting to acquire flc_lock\nin generic_delete_lease. This means:\n1) sc_count in nfsd_break_one_deleg will not be decremented to 0;\n2) The nfs4_put_stid called by nfsd_break_one_deleg will not attempt to\nacquire cl_lock;\n3) Consequently, no deadlock condition is created.\n\nGiven that sc_count in nfsd_break_one_deleg remains non-zero, we can\nsafely perform refcount_dec on sc_count directly. This approach\neffectively avoids triggering deadlock warnings."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: nfsd: disminuir sc_count directamente si no se puede poner en cola dl_recall Se produjo una advertencia de bloqueo al invocar nfs4_put_stid despu\u00e9s de una operaci\u00f3n de cola dl_recall fallida: T1 T2 nfs4_laundromat nfs4_get_client_reaplist nfs4_anylock_blockers __break_lease spin_lock // ctx->flc_lock spin_lock // clp->cl_lock nfs4_lockowner_has_blockers locks_owner_has_blockers spin_lock // flctx->flc_lock nfsd_break_deleg_cb nfsd_break_one_deleg nfs4_put_stid refcount_dec_and_lock spin_lock // clp->cl_lock Cuando se abre un archivo, se genera una nfs4_delegation asignado con sc_count inicializado a 1, y el file_lease contiene una referencia a la delegaci\u00f3n. El file_lease se asocia entonces con el archivo a trav\u00e9s de kernel_setlease. La disociaci\u00f3n se realiza en nfsd4_delegreturn mediante la siguiente cadena de llamadas: nfsd4_delegreturn --> destroy_delegation --> destroy_unhashed_deleg --> nfs4_unlock_deleg_lease --> kernel_setlease --> generic_delete_lease La referencia sc_count correspondiente se liberar\u00e1 despu\u00e9s de esta disociaci\u00f3n. Dado que nfsd_break_one_deleg se ejecuta mientras mantiene el flc_lock, el proceso de disociaci\u00f3n se bloquea al intentar adquirir flc_lock en generic_delete_lease. Esto significa: 1) sc_count en nfsd_break_one_deleg no se decrementar\u00e1 a 0; 2) El `nfs4_put_stid` llamado por `nfsd_break_one_deleg` no intentar\u00e1 adquirir `cl_lock`; 3) Por consiguiente, no se crea ninguna condici\u00f3n de interbloqueo. Dado que `sc_count` en `nfsd_break_one_deleg` permanece distinto de cero, podemos ejecutar `refcount_dec` en `sc_count` directamente. Este enfoque evita eficazmente la activaci\u00f3n de advertencias de interbloqueo."}], "lastModified": "2025-11-12T19:45:36.967", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FC39818A-8C20-4C6C-8155-9E364AC53D54", "versionEndExcluding": "6.12.25", "versionStartIncluding": "6.12.23"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "124AE182-7E9F-4410-9E08-5976ED49C6A4", "versionEndExcluding": "6.14", "versionStartIncluding": "6.13.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "ABA7F402-1511-4ECC-907D-578BA5B25742", "versionEndExcluding": "6.14.4", "versionStartIncluding": "6.14.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.10.236:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9160FCF1-2EF7-4794-86E9-26699C94A1FA"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.15.180:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5BC2D57B-41D0-407A-94E2-C73578390691"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.1.134:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5712D157-5E0C-40C1-97C5-7256A0103FC7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.6.87:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D5321373-E31B-44C8-84D5-0AC97FF10114"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8D465631-2980-487A-8E65-40AE2B9F8ED1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4C9D071F-B28E-46EC-AC61-22B913390211"}], "operator": "OR"}]}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}