CVE-2024-50114

{"id": "CVE-2024-50114", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "published": "2024-11-05T18:15:14.630", "references": [{"url": "https://git.kernel.org/stable/c/6bcc2890b883ba1d16b8942937750565f6e9db0d", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ae8f8b37610269009326f4318df161206c59843e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-416"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Unregister redistributor for failed vCPU creation\n\nAlex reports that syzkaller has managed to trigger a use-after-free when\ntearing down a VM:\n\n BUG: KASAN: slab-use-after-free in kvm_put_kvm+0x300/0xe68 virt/kvm/kvm_main.c:5769\n Read of size 8 at addr ffffff801c6890d0 by task syz.3.2219/10758\n\n CPU: 3 UID: 0 PID: 10758 Comm: syz.3.2219 Not tainted 6.11.0-rc6-dirty #64\n Hardware name: linux,dummy-virt (DT)\n Call trace:\n dump_backtrace+0x17c/0x1a8 arch/arm64/kernel/stacktrace.c:317\n show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324\n __dump_stack lib/dump_stack.c:93 [inline]\n dump_stack_lvl+0x94/0xc0 lib/dump_stack.c:119\n print_report+0x144/0x7a4 mm/kasan/report.c:377\n kasan_report+0xcc/0x128 mm/kasan/report.c:601\n __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381\n kvm_put_kvm+0x300/0xe68 virt/kvm/kvm_main.c:5769\n kvm_vm_release+0x4c/0x60 virt/kvm/kvm_main.c:1409\n __fput+0x198/0x71c fs/file_table.c:422\n ____fput+0x20/0x30 fs/file_table.c:450\n task_work_run+0x1cc/0x23c kernel/task_work.c:228\n do_notify_resume+0x144/0x1a0 include/linux/resume_user_mode.h:50\n el0_svc+0x64/0x68 arch/arm64/kernel/entry-common.c:169\n el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730\n el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598\n\nUpon closer inspection, it appears that we do not properly tear down the\nMMIO registration for a vCPU that fails creation late in the game, e.g.\na vCPU w/ the same ID already exists in the VM.\n\nIt is important to consider the context of commit that introduced this bug\nby moving the unregistration out of __kvm_vgic_vcpu_destroy(). That\nchange correctly sought to avoid an srcu v. config_lock inversion by\nbreaking up the vCPU teardown into two parts, one guarded by the\nconfig_lock.\n\nFix the use-after-free while avoiding lock inversion by adding a\nspecial-cased unregistration to __kvm_vgic_vcpu_destroy(). This is safe\nbecause failed vCPUs are torn down outside of the config_lock."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: KVM: arm64: Anular el registro del redistribuidor en caso de creaci\u00f3n fallida de una vCPU. Alex informa que syzkaller ha conseguido activar un use-after-free al desmantelar una m\u00e1quina virtual: ERROR: KASAN: slab-use-after-free en kvm_put_kvm+0x300/0xe68 virt/kvm/kvm_main.c:5769 Lectura de tama\u00f1o 8 en la direcci\u00f3n ffffff801c6890d0 por la tarea syz.3.2219/10758 CPU: 3 UID: 0 PID: 10758 Comm: syz.3.2219 No contaminado 6.11.0-rc6-dirty #64 Nombre del hardware: linux,dummy-virt (DT) Rastreo de llamadas: dump_backtrace+0x17c/0x1a8 arch/arm64/kernel/stacktrace.c:317 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324 __dump_stack lib/dump_stack.c:93 [en l\u00ednea] dump_stack_lvl+0x94/0xc0 lib/dump_stack.c:119 print_report+0x144/0x7a4 mm/kasan/report.c:377 kasan_report+0xcc/0x128 mm/kasan/report.c:601 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381 kvm_put_kvm+0x300/0xe68 virt/kvm/kvm_main.c:5769 kvm_vm_release+0x4c/0x60 virt/kvm/kvm_main.c:1409 __fput+0x198/0x71c fs/file_table.c:422 ____fput+0x20/0x30 fs/file_table.c:450 task_work_run+0x1cc/0x23c kernel/task_work.c:228 do_notify_resume+0x144/0x1a0 include/linux/resume_user_mode.h:50 el0_svc+0x64/0x68 arch/arm64/kernel/entry-common.c:169 el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 Tras una inspecci\u00f3n m\u00e1s detallada, parece que no eliminamos correctamente el registro MMIO para una vCPU que falla en la creaci\u00f3n tarde en el juego, por ejemplo, una vCPU con el mismo ID ya existe en la VM. Es importante considerar el contexto de la confirmaci\u00f3n que introdujo este error al mover la anulaci\u00f3n del registro fuera de __kvm_vgic_vcpu_destroy(). Ese cambio busc\u00f3 correctamente evitar una inversi\u00f3n de srcu v. config_lock al dividir el desmontaje de la vCPU en dos partes, una protegida por config_lock. Corrija el use-after-free mientras evita la inversi\u00f3n del bloqueo agregando una anulaci\u00f3n del registro con caso especial a __kvm_vgic_vcpu_destroy(). Esto es seguro porque las vCPU fallidas se eliminan fuera de config_lock."}], "lastModified": "2024-11-08T19:11:43.650", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "35973F0F-C32F-4D88-B0FE-C75F65A0002B", "versionEndExcluding": "6.11.6", "versionStartIncluding": "6.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7F361E1D-580F-4A2D-A509-7615F73167A1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "925478D0-3E3D-4E6F-ACD5-09F28D5DF82C"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "3C95E234-D335-4B6C-96BF-E2CEBD8654ED"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.12:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E0F717D8-3014-4F84-8086-0124B2111379"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}