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| author | Will Deacon <will@kernel.org> | 2023-05-18 12:58:44 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2023-05-19 12:20:30 +0300 |
| commit | 09cce60bddd6461a93a5bf434265a47827d1bc6f (patch) | |
| tree | c84563cbc42439f7939b36387b78e6e34873bc98 /arch/arm64/kvm | |
| parent | 62548732260976ca88fcb17ef98ab661e7ce7504 (diff) | |
| download | linux-09cce60bddd6461a93a5bf434265a47827d1bc6f.tar.xz | |
KVM: arm64: Prevent unconditional donation of unmapped regions from the host
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
Diffstat (limited to 'arch/arm64/kvm')
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/mem_protect.c | 14 |
1 files 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 2e9ec4a2a4a3..a8813b212996 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -575,7 +575,7 @@ 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, @@ -583,10 +583,7 @@ 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, @@ -601,8 +598,11 @@ 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; @@ -709,7 +709,7 @@ 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; |