KVM: PPC: Book3S HV: fix use-after-free in kvmhv_emulate_tlbie_all_lpid()
In the Linux kernel, the following vulnerability has been resolved: KVM: PPC: Book3S HV: fix use-after-free in kvmhv_emulate_tlbie_all_lpid() kvmhv_emulate_tlbie_all_lpid() iterates the nested-guest IDR and drops mmu_lock before calling kvmhv_emulate_tlbie_lpid(), but does not hold a reference on the kvm_nested_guest pointer obtained from the IDR. A concurrent vCPU issuing a single-LPID tlbie (is=2, ric=2) can race through kvmhv_flush_nested() -> kvmhv_remove_nested() -> idr_remove / --refcnt -> kvmhv_release_nested() -> kfree(gp) in that window, leaving the iterating vCPU with a dangling pointer. The subsequent mutex_lock(&gp->tlb_lock) and accesses to gp->shadow_pgtable, gp->shadow_lpid and gp->l1_host all touch freed memory. The free path is fully L1-controlled. Fix this by incrementing gp->refcnt inside the loop before dropping mmu_lock, mirroring what kvmhv_get_nested() does, and releasing the reference with kvmhv_put_nested() after the per-guest work completes. This is the same get/put discipline already used at every other call site that drops mmu_lock while holding a nested-guest pointer.
CVE-2026-98283
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98283
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
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"version": "e3b6b4661527e821ffbe3db83952fdb1e6e47c49",
"lessThan": "4d8f7b1f586375df8bce23a0909566ad5e852259",
"versionType": "git"
},
{
"status": "affected",
"version": "e3b6b4661527e821ffbe3db83952fdb1e6e47c49",
"lessThan": "e37fba1ba69385cff2d0e60b371ee19e7d1852d1",
"versionType": "git"
},
{
"status": "affected",
"version": "e3b6b4661527e821ffbe3db83952fdb1e6e47c49",
"lessThan": "24b634852413229bb8340d908b115c3365f3a247",
"versionType": "git"
},
{
"status": "affected",
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"lessThan": "fbf69b7d0555ee83c871f58750770f74b7179ad1",
"versionType": "git"
},
{
"status": "affected",
"version": "e3b6b4661527e821ffbe3db83952fdb1e6e47c49",
"lessThan": "ec2d7a52b3996ae81131617b4afc0af31583c1b4",
"versionType": "git"
},
{
"status": "affected",
"version": "e3b6b4661527e821ffbe3db83952fdb1e6e47c49",
"lessThan": "51938dfa8a51a4f85328413fca9b6e21f9d2d088",
"versionType": "git"
}
],
"programFiles": [
"arch/powerpc/kvm/book3s_hv_nested.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.20"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.20",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.189",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.54",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.8",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"arch/powerpc/kvm/book3s_hv_nested.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98283
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #38361 · Revision 1
- Added to Heist Feed
- Publisher date