blob: 2d5a87f3337b74e91c2cfec008b08f080408ccaf [file] [log] [blame]
{
"containers": {
"cna": {
"providerMetadata": {
"orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86/mmu: Zap _all_ roots when unmapping gfn range in TDP MMU\n\nZap both valid and invalid roots when zapping/unmapping a gfn range, as\nKVM must ensure it holds no references to the freed page after returning\nfrom the unmap operation. Most notably, the TDP MMU doesn't zap invalid\nroots in mmu_notifier callbacks. This leads to use-after-free and other\nissues if the mmu_notifier runs to completion while an invalid root\nzapper yields as KVM fails to honor the requirement that there must be\n_no_ references to the page after the mmu_notifier returns.\n\nThe bug is most easily reproduced by hacking KVM to cause a collision\nbetween set_nx_huge_pages() and kvm_mmu_notifier_release(), but the bug\nexists between kvm_mmu_notifier_invalidate_range_start() and memslot\nupdates as well. Invalidating a root ensures pages aren't accessible by\nthe guest, and KVM won't read or write page data itself, but KVM will\ntrigger e.g. kvm_set_pfn_dirty() when zapping SPTEs, and thus completing\na zap of an invalid root _after_ the mmu_notifier returns is fatal.\n\n WARNING: CPU: 24 PID: 1496 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:173 [kvm]\n RIP: 0010:kvm_is_zone_device_pfn+0x96/0xa0 [kvm]\n Call Trace:\n <TASK>\n kvm_set_pfn_dirty+0xa8/0xe0 [kvm]\n __handle_changed_spte+0x2ab/0x5e0 [kvm]\n __handle_changed_spte+0x2ab/0x5e0 [kvm]\n __handle_changed_spte+0x2ab/0x5e0 [kvm]\n zap_gfn_range+0x1f3/0x310 [kvm]\n kvm_tdp_mmu_zap_invalidated_roots+0x50/0x90 [kvm]\n kvm_mmu_zap_all_fast+0x177/0x1a0 [kvm]\n set_nx_huge_pages+0xb4/0x190 [kvm]\n param_attr_store+0x70/0x100\n module_attr_store+0x19/0x30\n kernfs_fop_write_iter+0x119/0x1b0\n new_sync_write+0x11c/0x1b0\n vfs_write+0x1cc/0x270\n ksys_write+0x5f/0xe0\n do_syscall_64+0x38/0xc0\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n </TASK>"
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"arch/x86/kvm/mmu/tdp_mmu.c"
],
"versions": [
{
"version": "b7cccd397f310739fb85383033e95580f99927e0",
"lessThan": "af47248407c0c5ae52a752af1ab5ce5b0db91502",
"status": "affected",
"versionType": "git"
},
{
"version": "b7cccd397f310739fb85383033e95580f99927e0",
"lessThan": "0c8a8da182d4333d9bbb9131d765145568c847b2",
"status": "affected",
"versionType": "git"
},
{
"version": "b7cccd397f310739fb85383033e95580f99927e0",
"lessThan": "8cf6f98ab1d16d5e607635a0c21c4231eb15367e",
"status": "affected",
"versionType": "git"
},
{
"version": "b7cccd397f310739fb85383033e95580f99927e0",
"lessThan": "d62007edf01f5c11f75d0f4b1e538fc52a5b1982",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"arch/x86/kvm/mmu/tdp_mmu.c"
],
"versions": [
{
"version": "5.13",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.13",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.15.33",
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.16.19",
"lessThanOrEqual": "5.16.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.17.2",
"lessThanOrEqual": "5.17.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.18",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.13",
"versionEndExcluding": "5.15.33"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.13",
"versionEndExcluding": "5.16.19"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.13",
"versionEndExcluding": "5.17.2"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.13",
"versionEndExcluding": "5.18"
}
]
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/af47248407c0c5ae52a752af1ab5ce5b0db91502"
},
{
"url": "https://git.kernel.org/stable/c/0c8a8da182d4333d9bbb9131d765145568c847b2"
},
{
"url": "https://git.kernel.org/stable/c/8cf6f98ab1d16d5e607635a0c21c4231eb15367e"
},
{
"url": "https://git.kernel.org/stable/c/d62007edf01f5c11f75d0f4b1e538fc52a5b1982"
}
],
"title": "KVM: x86/mmu: Zap _all_ roots when unmapping gfn range in TDP MMU",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
"cveID": "CVE-2021-47639",
"requesterUserId": "gregkh@kernel.org",
"serial": "1",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.0"
}