KVM: arm64: Reassign nested_mmus array behind mmu_lock
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.18.35, 7.0.12
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Reassign nested_mmus array behind mmu_lock kvm->arch.nested_mmus[] is walked under kvm->mmu_lock, including from the MMU notifier path (kvm_unmap_gfn_range() -> kvm_nested_s2_unmap()), which can run at any time. kvm_vcpu_init_nested() reallocates the array and frees the old buffer while holding only kvm->arch.config_lock, so such a walker can reference the freed array. Allocate the new array outside of mmu_lock, as the allocation can sleep. Under the lock, copy the existing entries, fix up the back pointers and reassign the array. Free the old buffer after dropping the lock, as kvfree() can sleep as well.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From 4f128f8e1aaac189f83d0f828bcdb2986d8d2e51 · fixed in 918450ad6010df6ecd2efde12a1409e011da22d6; From 4f128f8e1aaac189f83d0f828bcdb2986d8d2e51 · fixed in 4424dbcb06d68e34e51c019a5781a7dc00731971; From 4f128f8e1aaac189f83d0f828bcdb2986d8d2e51 · fixed in 70543358fa08e0f7cebc3447c3b70fe97ad7aaa8
- Linux Linux
6.11
- KernelLinux
From 6.11.0 · fixed in 6.18.35; From 6.19.0 · fixed in 7.0.12