CVE-2024-53195

{"id": "CVE-2024-53195", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "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": "2024-12-27T14:15:27.137", "references": [{"url": "https://git.kernel.org/stable/c/38d7aacca09230fdb98a34194fec2af597e8e20d", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c16e2dba39ff6ae84bb8dc9c8e0fb21d9b2f6f5c", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/dd2f9861f27571d47998d71e7516bf7216db0b52", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/fe425d5239a28c21e0c83ee7a8f4cb210d29fdb4", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Get rid of userspace_irqchip_in_use\n\nImproper use of userspace_irqchip_in_use led to syzbot hitting the\nfollowing WARN_ON() in kvm_timer_update_irq():\n\nWARNING: CPU: 0 PID: 3281 at arch/arm64/kvm/arch_timer.c:459\nkvm_timer_update_irq+0x21c/0x394\nCall trace:\n kvm_timer_update_irq+0x21c/0x394 arch/arm64/kvm/arch_timer.c:459\n kvm_timer_vcpu_reset+0x158/0x684 arch/arm64/kvm/arch_timer.c:968\n kvm_reset_vcpu+0x3b4/0x560 arch/arm64/kvm/reset.c:264\n kvm_vcpu_set_target arch/arm64/kvm/arm.c:1553 [inline]\n kvm_arch_vcpu_ioctl_vcpu_init arch/arm64/kvm/arm.c:1573 [inline]\n kvm_arch_vcpu_ioctl+0x112c/0x1b3c arch/arm64/kvm/arm.c:1695\n kvm_vcpu_ioctl+0x4ec/0xf74 virt/kvm/kvm_main.c:4658\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:907 [inline]\n __se_sys_ioctl fs/ioctl.c:893 [inline]\n __arm64_sys_ioctl+0x108/0x184 fs/ioctl.c:893\n __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]\n invoke_syscall+0x78/0x1b8 arch/arm64/kernel/syscall.c:49\n el0_svc_common+0xe8/0x1b0 arch/arm64/kernel/syscall.c:132\n do_el0_svc+0x40/0x50 arch/arm64/kernel/syscall.c:151\n el0_svc+0x54/0x14c arch/arm64/kernel/entry-common.c:712\n el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730\n el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598\n\nThe following sequence led to the scenario:\n - Userspace creates a VM and a vCPU.\n - The vCPU is initialized with KVM_ARM_VCPU_PMU_V3 during\n KVM_ARM_VCPU_INIT.\n - Without any other setup, such as vGIC or vPMU, userspace issues\n KVM_RUN on the vCPU. Since the vPMU is requested, but not setup,\n kvm_arm_pmu_v3_enable() fails in kvm_arch_vcpu_run_pid_change().\n As a result, KVM_RUN returns after enabling the timer, but before\n incrementing 'userspace_irqchip_in_use':\n kvm_arch_vcpu_run_pid_change()\n ret = kvm_arm_pmu_v3_enable()\n if (!vcpu->arch.pmu.created)\n return -EINVAL;\n if (ret)\n return ret;\n [...]\n if (!irqchip_in_kernel(kvm))\n static_branch_inc(&userspace_irqchip_in_use);\n - Userspace ignores the error and issues KVM_ARM_VCPU_INIT again.\n Since the timer is already enabled, control moves through the\n following flow, ultimately hitting the WARN_ON():\n kvm_timer_vcpu_reset()\n if (timer->enabled)\n kvm_timer_update_irq()\n if (!userspace_irqchip())\n ret = kvm_vgic_inject_irq()\n ret = vgic_lazy_init()\n if (unlikely(!vgic_initialized(kvm)))\n if (kvm->arch.vgic.vgic_model !=\n KVM_DEV_TYPE_ARM_VGIC_V2)\n return -EBUSY;\n WARN_ON(ret);\n\nTheoretically, since userspace_irqchip_in_use's functionality can be\nsimply replaced by '!irqchip_in_kernel()', get rid of the static key\nto avoid the mismanagement, which also helps with the syzbot issue."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: KVM: arm64: deshacerse de userspace_irqchip_in_use El uso inadecuado de userspace_irqchip_in_use provoc\u00f3 que syzbot ejecutara el siguiente WARN_ON() en kvm_timer_update_irq(): ADVERTENCIA: CPU: 0 PID: 3281 en arch/arm64/kvm/arch_timer.c:459 kvm_timer_update_irq+0x21c/0x394 Rastreo de llamadas: kvm_timer_update_irq+0x21c/0x394 arch/arm64/kvm/arch_timer.c:459 kvm_timer_vcpu_reset+0x158/0x684 arch/arm64/kvm/arch_timer.c:968 kvm_reset_vcpu+0x3b4/0x560 arch/arm64/kvm/reset.c:264 kvm_vcpu_set_target arch/arm64/kvm/arm.c:1553 [en l\u00ednea] kvm_arch_vcpu_ioctl_vcpu_init arch/arm64/kvm/arm.c:1573 [en l\u00ednea] kvm_arch_vcpu_ioctl+0x112c/0x1b3c arch/arm64/kvm/arm.c:1695 kvm_vcpu_ioctl+0x4ec/0xf74 virt/kvm/kvm_main.c:4658 vfs_ioctl fs/ioctl.c:51 [en l\u00ednea] __do_sys_ioctl fs/ioctl.c:907 [en l\u00ednea] __se_sys_ioctl fs/ioctl.c:893 [en l\u00ednea] __arm64_sys_ioctl+0x108/0x184 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [en l\u00ednea] anybody_syscall+0x78/0x1b8 another_syscall arch/arm64/kernel/syscall.c:49 another_svc_common+0xe8/0x1b0 another_syscall arch/arm64/kernel/syscall.c:132 another_svc+0x40/0x50 another_syscall arch/arm64/kernel/syscall.c:151 another_svc+0x54/0x14c arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 La siguiente secuencia condujo al escenario: - El espacio de usuario crea una VM y una vCPU. - La vCPU se inicializa con KVM_ARM_VCPU_PMU_V3 durante KVM_ARM_VCPU_INIT. - Sin ninguna otra configuraci\u00f3n, como vGIC o vPMU, el espacio de usuario emite KVM_RUN en la vCPU. Dado que se solicita la vPMU, pero no se configura, kvm_arm_pmu_v3_enable() falla en kvm_arch_vcpu_run_pid_change(). Como resultado, KVM_RUN regresa despu\u00e9s de habilitar el temporizador, pero antes de incrementar 'userspace_irqchip_in_use': kvm_arch_vcpu_run_pid_change() ret = kvm_arm_pmu_v3_enable() if (!vcpu->arch.pmu.created) return -EINVAL; if (ret) return ret; [...] if (!irqchip_in_kernel(kvm)) static_branch_inc(&userspace_irqchip_in_use); - Userspace ignora el error y emite KVM_ARM_VCPU_INIT nuevamente. Como el temporizador ya est\u00e1 habilitado, el control se mueve a trav\u00e9s del siguiente flujo, y finalmente llega a WARN_ON(): kvm_timer_vcpu_reset() if (timer->enabled) kvm_timer_update_irq() if (!userspace_irqchip()) ret = kvm_vgic_inject_irq() ret = vgic_lazy_init() if (unlikely(!vgic_initialized(kvm))) if (kvm->arch.vgic.vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2) return -EBUSY; WARN_ON(ret); Te\u00f3ricamente, dado que la funcionalidad de userspace_irqchip_in_use se puede reemplazar simplemente por '!irqchip_in_kernel()', desh\u00e1gase de la clave est\u00e1tica para evitar la mala administraci\u00f3n, lo que tambi\u00e9n ayuda con el problema de syzbot."}], "lastModified": "2025-10-08T14:07:06.337", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "523573B1-32B0-4CEF-A666-DC2DA3D85104", "versionEndExcluding": "6.6.64"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "21434379-192D-472F-9B54-D45E3650E893", "versionEndExcluding": "6.11.11", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D8882B1B-2ABC-4838-AC1D-DBDBB5764776", "versionEndExcluding": "6.12.2", "versionStartIncluding": "6.12"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}