CVE-2026-98433 affecting package kernel 6.6.157.1-1
In the Linux kernel, the following vulnerability has been resolved: KVM: PPC: Book3S HV: fix secure device page leak on uv_page_in() failure In kvmppc_svm_page_in(), if uv_page_in() fails after kvmppc_uvmem_get_page() has succeeded, the secure device page is never released. kvmppc_uvmem_get_page() sets a bit in kvmppc_uvmem_bitmap, allocates a kvmppc_uvmem_page_pvt struct, marks the GFN as KVMPPC_GFN_UVMEM_PFN, and calls zone_device_page_init() which sets refcount=1 and locks the page. The subsequent goto out_finalize skips the *mig.dst assignment, so migrate_vma_finalize() is a no-op for the page, and none of those resources are ever reclaimed. Each occurrence permanently consumes one entry from the firmware-bounded secure memory pool (kvmppc_uvmem_bitmap), leaks pvt, and leaves the GFN marked as secure — making it unusable for the lifetime of the VM. The twin __kvmppc_svm_page_out() already handles the analogous uv_page_out() failure correctly with unlock_page(dpage); __free_page(dpage). Apply the same pattern here: unlock_page() followed by put_page(), which chains through free_zone_device_folio() into kvmppc_uvmem_folio_free() to clear the bitmap bit, free pvt, and reset the GFN state. Reachable whenever uv_page_in() returns an error (e.g. UV pool exhaustion) on any POWER9/10 + Ultravisor/PEF system.
- Products
- kernel
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-98433
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 17:23 UTC · Revision 1
Source evidence
CVE-2026-98433 affecting package kernel 6.6.157.1-1
core-osv · Original sourcePublished 18 Oct 2026, 15:16 UTC
In the Linux kernel, the following vulnerability has been resolved: KVM: PPC: Book3S HV: fix secure device page leak on uv_page_in() failure In kvmppc_svm_page_in(), if uv_page_in() fails after kvmppc_uvmem_get_page() has succeeded, the secure device page is never released. kvmppc_uvmem_get_page() sets a bit in kvmppc_uvmem_bitmap, allocates a kvmppc_uvmem_page_pvt struct, marks the GFN as KVMPPC_GFN_UVMEM_PFN, and calls zone_device_page_init() which sets refcount=1 and locks the page. The subsequent goto out_finalize skips the *mig.dst assignment, so migrate_vma_finalize() is a no-op for the page, and none of those resources are ever reclaimed. Each occurrence permanently consumes one entry from the firmware-bounded secure memory pool (kvmppc_uvmem_bitmap), leaks pvt, and leaves the GFN marked as secure — making it unusable for the lifetime of the VM. The twin __kvmppc_svm_page_out() already handles the analogous uv_page_out() failure correctly with unlock_page(dpage); __free_page(dpage). Apply the same pattern here: unlock_page() followed by put_page(), which chains through free_zone_device_folio() into kvmppc_uvmem_folio_free() to clear the bitmap bit, free pvt, and reset the GFN state. Reachable whenever uv_page_in() returns an error (e.g. UV pool exhaustion) on any POWER9/10 + Ultravisor/PEF system.
osv:AZL-108734
kernel
Fixed versions: Not specified
Complete source record
{
"id": "be8e625350fbd54d37cd5e888117bd525bb60432620593ba4792165d4198a4df",
"url": "https://osv.dev/vulnerability/AZL-108734",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2026-98433 affecting package kernel 6.6.157.1-1",
"summary": "In the Linux kernel, the following vulnerability has been resolved: KVM: PPC: Book3S HV: fix secure device page leak on uv_page_in() failure In kvmppc_svm_page_in(), if uv_page_in() fails after kvmppc_uvmem_get_page() has succeeded, the secure device page is never released. kvmppc_uvmem_get_page() sets a bit in kvmppc_uvmem_bitmap, allocates a kvmppc_uvmem_page_pvt struct, marks the GFN as KVMPPC_GFN_UVMEM_PFN, and calls zone_device_page_init() which sets refcount=1 and locks the page. The subsequent goto out_finalize skips the *mig.dst assignment, so migrate_vma_finalize() is a no-op for the page, and none of those resources are ever reclaimed. Each occurrence permanently consumes one entry from the firmware-bounded secure memory pool (kvmppc_uvmem_bitmap), leaks pvt, and leaves the GFN marked as secure — making it unusable for the lifetime of the VM. The twin __kvmppc_svm_page_out() already handles the analogous uv_page_out() failure correctly with unlock_page(dpage); __free_page(dpage). Apply the same pattern here: unlock_page() followed by put_page(), which chains through free_zone_device_folio() into kvmppc_uvmem_folio_free() to clear the bitmap bit, free pvt, and reset the GFN state. Reachable whenever uv_page_in() returns an error (e.g. UV pool exhaustion) on any POWER9/10 + Ultravisor/PEF system.",
"evidence": "osv:AZL-108734",
"products": [
{
"name": {
"value": "kernel",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "AZL-108734",
"aliases": [
"AZL-108734"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"last_affected": "6.6.157.1-1"
}
]
}
],
"package": {
"name": "kernel",
"purl": "pkg:rpm/azure-linux/kernel",
"ecosystem": "Azure Linux:3"
},
"database_specific": {
"source": "https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-108734.json"
}
}
],
"modified": "2026-10-27T05:36:16Z",
"provider": "osv",
"upstream": [
"CVE-2026-98433"
],
"references": [
"https://nvd.nist.gov/vuln/detail/CVE-2026-98433"
]
},
"related_cves": [
{
"value": "CVE-2026-98433",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 460403,
"published_at": "2026-10-18T15:16:53+00:00"
}