CVE-2025-38621

{"id": "CVE-2025-38621", "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": "2025-08-22T16:15:35.460", "references": [{"url": "https://git.kernel.org/stable/c/13017b427118f4311471ee47df74872372ca8482", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b5fbe940862339cdcc34dea7a057ad18d18fa137", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "[email protected]", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmd: make rdev_addable usable for rcu mode\n\nOur testcase trigger panic:\n\nBUG: kernel NULL pointer dereference, address: 00000000000000e0\n...\nOops: Oops: 0000 [#1] SMP NOPTI\nCPU: 2 UID: 0 PID: 85 Comm: kworker/2:1 Not tainted 6.16.0+ #94\nPREEMPT(none)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS\n1.16.1-2.fc37 04/01/2014\nWorkqueue: md_misc md_start_sync\nRIP: 0010:rdev_addable+0x4d/0xf0\n...\nCall Trace:\n <TASK>\n md_start_sync+0x329/0x480\n process_one_work+0x226/0x6d0\n worker_thread+0x19e/0x340\n kthread+0x10f/0x250\n ret_from_fork+0x14d/0x180\n ret_from_fork_asm+0x1a/0x30\n </TASK>\nModules linked in: raid10\nCR2: 00000000000000e0\n---[ end trace 0000000000000000 ]---\nRIP: 0010:rdev_addable+0x4d/0xf0\n\nmd_spares_need_change in md_start_sync will call rdev_addable which\nprotected by rcu_read_lock/rcu_read_unlock. This rcu context will help\nprotect rdev won't be released, but rdev->mddev will be set to NULL\nbefore we call synchronize_rcu in md_kick_rdev_from_array. Fix this by\nusing READ_ONCE and check does rdev->mddev still alive."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: md: hacer que rdev_addable sea utilizable para el modo rcu Nuestro caso de prueba activa el p\u00e1nico: ERROR: desreferencia de puntero NULL del kernel, direcci\u00f3n: 00000000000000e0 ... Oops: Oops: 0000 [#1] SMP NOPTI CPU: 2 UID: 0 PID: 85 Comm: kworker/2:1 No contaminado 6.16.0+ #94 PREEMPT(none) Nombre del hardware: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 01/04/2014 Cola de trabajo: md_misc md_start_sync RIP: 0010:rdev_addable+0x4d/0xf0 ... Rastreo de llamadas: M\u00f3dulos vinculados en: raid10 CR2: 00000000000000e0 ---[ fin de seguimiento 000000000000000 ]--- RIP: 0010:rdev_addable+0x4d/0xf0 md_spares_need_change en md_start_sync llamar\u00e1 a rdev_addable que est\u00e1 protegido por rcu_read_lock/rcu_read_unlock. Este contexto rcu ayudar\u00e1 a proteger rdev, ya que no se liberar\u00e1, pero rdev-&gt;mddev se establecer\u00e1 en NULL antes de llamar a synchronize_rcu en md_kick_rdev_from_array. Para solucionar esto, use READ_ONCE y compruebe si rdev-&gt;mddev sigue activo."}], "lastModified": "2025-11-26T17:46:17.203", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D14ECFCD-ABDE-4C5C-8550-773D587E5383", "versionEndExcluding": "6.16.1", "versionStartIncluding": "6.7"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}