CVE-2024-41070

{"id": "CVE-2024-41070", "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": "2024-07-29T15:15:14.787", "references": [{"url": "https://git.kernel.org/stable/c/4cdf6926f443c84f680213c7aafbe6f91a5fcbc0", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/5f856023971f97fff74cfaf21b48ec320147b50a", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/82c7a4cf14aa866f8f7f09e662b02eddc49ee0bf", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/9975f93c760a32453d7639cf6fcf3f73b4e71ffe", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/a986fa57fd81a1430e00b3c6cf8a325d6f894a63", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b26c8c85463ef27a522d24fcd05651f0bb039e47", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/be847bb20c809de8ac124431b556f244400b0491", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/4cdf6926f443c84f680213c7aafbe6f91a5fcbc0", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/5f856023971f97fff74cfaf21b48ec320147b50a", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/82c7a4cf14aa866f8f7f09e662b02eddc49ee0bf", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/9975f93c760a32453d7639cf6fcf3f73b4e71ffe", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/a986fa57fd81a1430e00b3c6cf8a325d6f894a63", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/b26c8c85463ef27a522d24fcd05651f0bb039e47", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/be847bb20c809de8ac124431b556f244400b0491", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Modified", "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: PPC: Book3S HV: Prevent UAF in kvm_spapr_tce_attach_iommu_group()\n\nAl reported a possible use-after-free (UAF) in kvm_spapr_tce_attach_iommu_group().\n\nIt looks up `stt` from tablefd, but then continues to use it after doing\nfdput() on the returned fd. After the fdput() the tablefd is free to be\nclosed by another thread. The close calls kvm_spapr_tce_release() and\nthen release_spapr_tce_table() (via call_rcu()) which frees `stt`.\n\nAlthough there are calls to rcu_read_lock() in\nkvm_spapr_tce_attach_iommu_group() they are not sufficient to prevent\nthe UAF, because `stt` is used outside the locked regions.\n\nWith an artifcial delay after the fdput() and a userspace program which\ntriggers the race, KASAN detects the UAF:\n\n BUG: KASAN: slab-use-after-free in kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm]\n Read of size 4 at addr c000200027552c30 by task kvm-vfio/2505\n CPU: 54 PID: 2505 Comm: kvm-vfio Not tainted 6.10.0-rc3-next-20240612-dirty #1\n Hardware name: 8335-GTH POWER9 0x4e1202 opal:skiboot-v6.5.3-35-g1851b2a06 PowerNV\n Call Trace:\n dump_stack_lvl+0xb4/0x108 (unreliable)\n print_report+0x2b4/0x6ec\n kasan_report+0x118/0x2b0\n __asan_load4+0xb8/0xd0\n kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm]\n kvm_vfio_set_attr+0x524/0xac0 [kvm]\n kvm_device_ioctl+0x144/0x240 [kvm]\n sys_ioctl+0x62c/0x1810\n system_call_exception+0x190/0x440\n system_call_vectored_common+0x15c/0x2ec\n ...\n Freed by task 0:\n ...\n kfree+0xec/0x3e0\n release_spapr_tce_table+0xd4/0x11c [kvm]\n rcu_core+0x568/0x16a0\n handle_softirqs+0x23c/0x920\n do_softirq_own_stack+0x6c/0x90\n do_softirq_own_stack+0x58/0x90\n __irq_exit_rcu+0x218/0x2d0\n irq_exit+0x30/0x80\n arch_local_irq_restore+0x128/0x230\n arch_local_irq_enable+0x1c/0x30\n cpuidle_enter_state+0x134/0x5cc\n cpuidle_enter+0x6c/0xb0\n call_cpuidle+0x7c/0x100\n do_idle+0x394/0x410\n cpu_startup_entry+0x60/0x70\n start_secondary+0x3fc/0x410\n start_secondary_prolog+0x10/0x14\n\nFix it by delaying the fdput() until `stt` is no longer in use, which\nis effectively the entire function. To keep the patch minimal add a call\nto fdput() at each of the existing return paths. Future work can convert\nthe function to goto or __cleanup style cleanup.\n\nWith the fix in place the test case no longer triggers the UAF."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: KVM: PPC: Book3S HV: Prevenir UAF en kvm_spapr_tce_attach_iommu_group() Al inform\u00f3 un posible use after free (UAF) en kvm_spapr_tce_attach_iommu_group(). Busca `stt` en tablefd, pero luego contin\u00faa us\u00e1ndolo despu\u00e9s de realizar fdput() en el fd devuelto. Despu\u00e9s de fdput(), otro hilo puede cerrar el tablefd. El cierre llama a kvm_spapr_tce_release() y luego a release_spapr_tce_table() (a trav\u00e9s de call_rcu()) que libera `stt`. Aunque hay llamadas a rcu_read_lock() en kvm_spapr_tce_attach_iommu_group(), no son suficientes para evitar la UAF, porque `stt` se usa fuera de las regiones bloqueadas. Con un retraso artificial despu\u00e9s de fdput() y un programa de espacio de usuario que desencadena la ejecuci\u00f3n, KASAN detecta la UAF: ERROR: KASAN: slab-use-after-free in kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm] Lectura de tama\u00f1o 4 en direcci\u00f3n c000200027552c30 por tarea kvm-vfio/2505 CPU: 54 PID: 2505 Comm: kvm-vfio Not tainted 6.10.0-rc3-next-20240612-dirty #1 Nombre de hardware: 8335-GTH POWER9 0x4e1202 opal:skiboot-v6.5.3-35 -g1851b2a06 Seguimiento de llamadas de PowerNV: dump_stack_lvl+0xb4/0x108 (no confiable) print_report+0x2b4/0x6ec kasan_report+0x118/0x2b0 __asan_load4+0xb8/0xd0 kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm] kvm_vfio_set_attr+0x524/0xac0 [kvm] kvm_device_ioctl+0x144/0x240 [kvm] sys_ioctl+0x62c/0x1810 system_call_exception+0x190/0x440 system_call_vectored_common+0x15c/0x2ec ... Liberado por la tarea 0: ... kfree+0xec/0x3e0 release_spapr_tce_table+0xd4/0x11c [rcu_core+0x568/0 x16a0 handle_softirqs+0x23c /0x920 do_softirq_own_stack+0x6c/0x90 do_softirq_own_stack+0x58/0x90 __irq_exit_rcu+0x218/0x2d0 irq_exit+0x30/0x80 arch_local_irq_restore+0x128/0x230 arch_local_irq_enable+0x1c/0x 30 cpuidle_enter_state+0x134/0x5cc cpuidle_enter+0x6c/0xb0 call_cpuidle+0x7c/0x100 do_idle+0x394 /0x410 cpu_startup_entry+0x60/0x70 start_secondary+0x3fc/0x410 start_secondary_prolog+0x10/0x14 Solucionarlo retrasando fdput() hasta que `stt` ya no est\u00e9 en uso, que es efectivamente toda la funci\u00f3n. Para mantener el parche m\u00ednimo, agregue una llamada a fdput() en cada una de las rutas de retorno existentes. El trabajo futuro puede convertir la funci\u00f3n a limpieza de estilo goto o __cleanup. Con la soluci\u00f3n implementada, el caso de prueba ya no activa la UAF."}], "lastModified": "2024-11-21T09:32:11.070", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BCD1D392-BEF8-4D8D-B191-C64E1875241F", "versionEndExcluding": "5.4.281"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "12CD4E48-26A1-40B4-AF6A-1CC066193F4C", "versionEndExcluding": "5.10.223", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "3D6B1E23-6E6C-4761-ACD4-EA687A95F56F", "versionEndExcluding": "5.15.164", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2B46438B-72B8-4053-8554-94AED3EB13EB", "versionEndExcluding": "6.1.101", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "972274A2-D688-4C37-BE42-689B58B4C225", "versionEndExcluding": "6.6.42", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "01E300B3-8B39-4A2D-8B03-4631433D3915", "versionEndExcluding": "6.9.11", "versionStartIncluding": "6.7"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}