CVE-2021-47450
KVM: arm64: Fix host stage-2 PGD refcount
Vexday Risk Score
3Baixo
Decisão SSVC (CISA)
Track
Sem sinal de exploração → monitorar
CVSS —EPSS 0.2%KEV nãoPoC —Nuclei —Metasploit —Patch —
Ciclo de vida
22 mai 2024Publicada no NVD
Recomendação: Monitorar — sem sinal de exploração no momento.
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix host stage-2 PGD refcount
The KVM page-table library refcounts the pages of concatenated stage-2
PGDs individually. However, when running KVM in protected mode, the
host's stage-2 PGD is currently managed by EL2 as a single high-order
compound page, which can cause the refcount of the tail pages to reach 0
when they shouldn't, hence corrupting the page-table.
Fix this by introducing a new hyp_split_page() helper in the EL2 page
allocator (matching the kernel's split_page() function), and make use of
it from host_s2_zalloc_pages_exact().
Produtos afetados
Linux · Linux