From: Will Deacon will@kernel.org
commit 09cce60bddd6461a93a5bf434265a47827d1bc6f upstream.
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@google.com Fixes: e82edcc75c4e ("KVM: arm64: Implement do_share() helper for sharing memory") Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20230518095844.1178-1-will@kernel.org [ bp: s/ctx->addr/addr in __check_page_state_visitor due to missing commit "KVM: arm64: Combine visitor arguments into a context structure" in stable. ] Signed-off-by: Suraj Jitindar Singh surajjs@amazon.com --- 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 0f6c053686c7..0faa330a41ed 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -424,7 +424,7 @@ struct pkvm_mem_share {
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(u64 addr, u64 end, u32 level, @@ -435,10 +435,7 @@ static int __check_page_state_visitor(u64 addr, u64 end, u32 level, struct check_walk_data *d = arg; kvm_pte_t pte = *ptep;
- if (kvm_pte_valid(pte) && !addr_is_allowed_memory(kvm_pte_to_phys(pte))) - return -EINVAL; - - return d->get_page_state(pte) == d->desired ? 0 : -EPERM; + return d->get_page_state(pte, addr) == d->desired ? 0 : -EPERM; }
static int check_page_state_range(struct kvm_pgtable *pgt, u64 addr, u64 size, @@ -453,8 +450,11 @@ 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;
@@ -521,7 +521,7 @@ static int host_initiate_unshare(u64 *completer_addr, return __host_set_page_state_range(addr, size, PKVM_PAGE_OWNED); }
-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;