cve-2021-47450
Vulnerability from cvelistv5
Published
2024-05-22 06:19
Modified
2024-12-19 07:42
Severity ?
EPSS score ?
0.06% (0.14687)
Summary
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().
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39
Impacted products
Vendor Product Version
Linux Linux Version: 1025c8c0c6accfcbdc8f52ca1940160f65cd87d6
Version: 1025c8c0c6accfcbdc8f52ca1940160f65cd87d6
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   Linux Linux Version: 5.13
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