{"id":"CVE-2026-97988","summary":"vhost: invalidate vring access on IOTLB transitions","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nvhost: invalidate vring access on IOTLB transitions\n\nWhen VIRTIO_F_ACCESS_PLATFORM changes, cached vring pointers and IOTLB\nmetadata are interpreted in a different address space. Keeping them\nacross the transition can leave stale ring mappings in use.\n\nClearing d-\u003eiotlb before taking the VQ locks also lets a worker observe\na transient NULL d-\u003eiotlb and fall back to d-\u003eumem while translating a\ndescriptor.\n\nAdd a common vhost_clear_device_iotlb() helper for vhost-net and\nvhost-vsock. Take all VQ mutexes in index order before dropping the\ndevice-wide IOTLB, invalidate each VQ's cached ring access and metadata,\nclear pending IOTLB messages, and free the old table after the handoff.\nThis serializes the transition with workers and prevents mixed address\nspace mappings.\n\nOn the first direct-to-IOTLB transition, invalidate the cached vring\naddresses. When an existing device IOTLB is replaced, preserve the\nGIOVA ring addresses and reset only the metadata cache. After clearing\nACCESS_PLATFORM, userspace must configure the vring addresses for the\nnew address mode.\n\nvhost_vq_invalidate_access() clears desc, avail, and used together.\nTreat the VQ as invalidated only when all three are NULL, since a single\nGIOVA address may legitimately be zero.","modified":"2026-09-26T03:48:36.837129419Z","published":"2026-09-25T10:23:21.998Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97988.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4a454af8e56c1596ada1421ae5eba90c8896c7c7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e4f4761879a230aa59e569102a6ab9851847d833"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97988.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97988"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6b1e6cc7855b09a0a9bfa1d9f30172ba366f161c"},{"fixed":"4a454af8e56c1596ada1421ae5eba90c8896c7c7"},{"fixed":"e4f4761879a230aa59e569102a6ab9851847d833"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-97988.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.8.0"},{"fixed":"7.2.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-97988.json"}}],"schema_version":"1.9.0"}