From: Will Deacon <will@xxxxxxxxxx>
[ Upstream commit 09cce60bddd6461a93a5bf434265a47827d1bc6f ]
Since host stage-2 mappings are created lazily, we cannot rely solely on
the pte in order to recover the target physical address when checking a
host-initiated memory transition as this permits donation of unmapped
regions corresponding to MMIO or "no-map" memory.
Instead of inspecting the pte, move the addr_is_allowed_memory() check
into the host callback function where it is passed the physical address
directly from the walker.
Cc: Quentin Perret <qperret@xxxxxxxxxx>
Fixes: e82edcc75c4e ("KVM: arm64: Implement do_share() helper for sharing memory")
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230518095844.1178-1-will@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm64/kvm/hyp/nvhe/mem_protect.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
index 552653fa18be3..dab14d3ca7bb6 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
@@ -568,7 +568,7 @@ struct pkvm_mem_donation {
struct check_walk_data {
enum pkvm_page_state desired;
- enum pkvm_page_state (*get_page_state)(kvm_pte_t pte);
+ enum pkvm_page_state (*get_page_state)(kvm_pte_t pte, u64 addr);
};
static int __check_page_state_visitor(const struct kvm_pgtable_visit_ctx *ctx,
@@ -576,10 +576,7 @@ static int __check_page_state_visitor(const struct kvm_pgtable_visit_ctx *ctx,
{
struct check_walk_data *d = ctx->arg;
- if (kvm_pte_valid(ctx->old) && !addr_is_allowed_memory(kvm_pte_to_phys(ctx->old)))
- return -EINVAL;
-
- return d->get_page_state(ctx->old) == d->desired ? 0 : -EPERM;
+ return d->get_page_state(ctx->old, ctx->addr) == d->desired ? 0 : -EPERM;
}
static int check_page_state_range(struct kvm_pgtable *pgt, u64 addr, u64 size,
@@ -594,8 +591,11 @@ static int check_page_state_range(struct kvm_pgtable *pgt, u64 addr, u64 size,
return kvm_pgtable_walk(pgt, addr, size, &walker);
}
-static enum pkvm_page_state host_get_page_state(kvm_pte_t pte)
+static enum pkvm_page_state host_get_page_state(kvm_pte_t pte, u64 addr)
{
+ if (!addr_is_allowed_memory(addr))
+ return PKVM_NOPAGE;
+
if (!kvm_pte_valid(pte) && pte)
return PKVM_NOPAGE;
@@ -702,7 +702,7 @@ static int host_complete_donation(u64 addr, const struct pkvm_mem_transition *tx
return host_stage2_set_owner_locked(addr, size, host_id);
}
-static enum pkvm_page_state hyp_get_page_state(kvm_pte_t pte)
+static enum pkvm_page_state hyp_get_page_state(kvm_pte_t pte, u64 addr)
{
if (!kvm_pte_valid(pte))
return PKVM_NOPAGE;
--
2.39.2
