{ "data_version": "4.0", "data_type": "CVE", "data_format": "MITRE", "CVE_data_meta": { "ID": "CVE-2024-41070", "ASSIGNER": "cve@kernel.org", "STATE": "PUBLIC" }, "description": { "description_data": [ { "lang": "eng", "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." } ] }, "problemtype": { "problemtype_data": [ { "description": [ { "lang": "eng", "value": "n/a" } ] } ] }, "affects": { "vendor": { "vendor_data": [ { "vendor_name": "Linux", "product": { "product_data": [ { "product_name": "Linux", "version": { "version_data": [ { "version_affected": "<", "version_name": "1da177e4c3f4", "version_value": "be847bb20c80" }, { "version_value": "not down converted", "x_cve_json_5_version_data": { "versions": [ { "version": "5.4.281", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "custom" }, { "version": "5.10.223", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "custom" }, { "version": "5.15.164", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "custom" }, { "version": "6.1.101", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "custom" }, { "version": "6.6.42", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "custom" }, { "version": "6.9.11", "lessThanOrEqual": "6.9.*", "status": "unaffected", "versionType": "custom" }, { "version": "6.10", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ], "defaultStatus": "affected" } } ] } } ] } } ] } }, "references": { "reference_data": [ { "url": "https://git.kernel.org/stable/c/be847bb20c809de8ac124431b556f244400b0491", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/be847bb20c809de8ac124431b556f244400b0491" }, { "url": "https://git.kernel.org/stable/c/4cdf6926f443c84f680213c7aafbe6f91a5fcbc0", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/4cdf6926f443c84f680213c7aafbe6f91a5fcbc0" }, { "url": "https://git.kernel.org/stable/c/b26c8c85463ef27a522d24fcd05651f0bb039e47", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/b26c8c85463ef27a522d24fcd05651f0bb039e47" }, { "url": "https://git.kernel.org/stable/c/5f856023971f97fff74cfaf21b48ec320147b50a", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/5f856023971f97fff74cfaf21b48ec320147b50a" }, { "url": "https://git.kernel.org/stable/c/82c7a4cf14aa866f8f7f09e662b02eddc49ee0bf", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/82c7a4cf14aa866f8f7f09e662b02eddc49ee0bf" }, { "url": "https://git.kernel.org/stable/c/9975f93c760a32453d7639cf6fcf3f73b4e71ffe", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/9975f93c760a32453d7639cf6fcf3f73b4e71ffe" }, { "url": "https://git.kernel.org/stable/c/a986fa57fd81a1430e00b3c6cf8a325d6f894a63", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/a986fa57fd81a1430e00b3c6cf8a325d6f894a63" } ] }, "generator": { "engine": "bippy-c9c4e1df01b2" } }