diff options
| author | Quentin Perret <qperret@google.com> | 2024-04-23 16:05:13 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2024-05-01 16:46:58 +0100 |
| commit | cb16301626c339b3ccde93e5deea0569e508cb98 (patch) | |
| tree | 7e3f49b92bc65fc74dc76d665984e0629108789a /arch/arm64/kvm | |
| parent | 40099dedb4a81fbf13ebac3a9dafcb72c7722d6a (diff) | |
KVM: arm64: Issue CMOs when tearing down guest s2 pages
On the guest teardown path, pKVM will zero the pages used to back
the guest data structures before returning them to the host as
they may contain secrets (e.g. in the vCPU registers). However,
the zeroing is done using a cacheable alias, and CMOs are
missing, hence giving the host a potential opportunity to read
the original content of the guest structs from memory.
Fix this by issuing CMOs after zeroing the pages.
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240423150538.2103045-6-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'arch/arm64/kvm')
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/pkvm.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c index 492b7fc2c0c7..315d4ebe1d6a 100644 --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c @@ -441,6 +441,7 @@ static void *map_donated_memory(unsigned long host_va, size_t size) static void __unmap_donated_memory(void *va, size_t size) { + kvm_flush_dcache_to_poc(va, size); WARN_ON(__pkvm_hyp_donate_host(hyp_virt_to_pfn(va), PAGE_ALIGN(size) >> PAGE_SHIFT)); } |