CVE Published: 22/05/2024 |
CVE Updated: 04/11/2024 |
CVE Year: 2021 Source: Linux |
Vendor: Linux |
Product: Linux Status : PUBLISHED
CVE-2021-47450 Description
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().