From: Quentin Perret <qperret@google.com>
To: maz@kernel.org, james.morse@arm.com, alexandru.elisei@arm.com,
suzuki.poulose@arm.com, catalin.marinas@arm.com, will@kernel.org
Cc: linux-arm-kernel@lists.infradead.org,
kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org,
ardb@kernel.org, qwandor@google.com, tabba@google.com,
dbrazdil@google.com, kernel-team@android.com,
Quentin Perret <qperret@google.com>
Subject: [PATCH 14/14] KVM: arm64: Prevent late calls to __pkvm_create_private_mapping()
Date: Mon, 19 Jul 2021 11:47:35 +0100 [thread overview]
Message-ID: <20210719104735.3681732-15-qperret@google.com> (raw)
In-Reply-To: <20210719104735.3681732-1-qperret@google.com>
__pkvm_create_private_mapping() allows the host kernel to create
arbitrary mappings the hypervisor's "private" range. However, this is
only needed early on, and there should be no good reason for the host
to need this past the point where the pkvm static is set. Make sure to
stub the hypercall past this point to ensure it can't be used by a
malicious host.
Signed-off-by: Quentin Perret <qperret@google.com>
---
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
index f05ecbd382d0..e1d12f8122a7 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
@@ -154,7 +154,10 @@ static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ct
DECLARE_REG(size_t, size, host_ctxt, 2);
DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3);
- cpu_reg(host_ctxt, 1) = __pkvm_create_private_mapping(phys, size, prot);
+ if (static_branch_unlikely(&kvm_protected_mode_initialized))
+ cpu_reg(host_ctxt, 1) = -EPERM;
+ else
+ cpu_reg(host_ctxt, 1) = __pkvm_create_private_mapping(phys, size, prot);
}
static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt)
--
2.32.0.402.g57bb445576-goog
prev parent reply other threads:[~2021-07-19 10:48 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-19 10:47 [PATCH 00/14] Track shared pages at EL2 in protected mode Quentin Perret
2021-07-19 10:47 ` [PATCH 01/14] KVM: arm64: Provide the host_stage2_try() helper macro Quentin Perret
2021-07-20 13:57 ` Fuad Tabba
2021-07-19 10:47 ` [PATCH 02/14] KVM: arm64: Optimize kvm_pgtable_stage2_find_range() Quentin Perret
2021-07-19 10:47 ` [PATCH 03/14] KVM: arm64: Continue stage-2 map when re-creating mappings Quentin Perret
2021-07-19 12:14 ` Marc Zyngier
2021-07-19 13:32 ` Quentin Perret
2021-07-20 8:26 ` Marc Zyngier
2021-07-20 11:56 ` Quentin Perret
2021-07-19 10:47 ` [PATCH 04/14] KVM: arm64: Rename KVM_PTE_LEAF_ATTR_S2_IGNORED Quentin Perret
2021-07-19 10:47 ` [PATCH 05/14] KVM: arm64: Don't overwrite ignored bits with owner id Quentin Perret
2021-07-19 12:55 ` Marc Zyngier
2021-07-19 13:39 ` Quentin Perret
2021-07-20 8:46 ` Marc Zyngier
2021-07-19 10:47 ` [PATCH 06/14] KVM: arm64: Tolerate re-creating hyp mappings to set ignored bits Quentin Perret
2021-07-20 10:17 ` Fuad Tabba
2021-07-20 10:30 ` Quentin Perret
2021-07-20 10:59 ` Fuad Tabba
2021-07-20 11:14 ` Quentin Perret
2021-07-19 10:47 ` [PATCH 07/14] KVM: arm64: Enable forcing page-level stage-2 mappings Quentin Perret
2021-07-19 14:24 ` Marc Zyngier
2021-07-19 15:36 ` Quentin Perret
2021-07-19 10:47 ` [PATCH 08/14] KVM: arm64: Add support for tagging shared pages in page-table Quentin Perret
2021-07-19 14:43 ` Marc Zyngier
2021-07-19 15:49 ` Quentin Perret
2021-07-20 10:13 ` Marc Zyngier
2021-07-20 11:48 ` Quentin Perret
2021-07-20 13:48 ` Fuad Tabba
2021-07-20 14:06 ` Quentin Perret
2021-07-21 7:34 ` Fuad Tabba
2021-07-19 10:47 ` [PATCH 09/14] KVM: arm64: Mark host bss and rodata section as shared Quentin Perret
2021-07-19 15:01 ` Marc Zyngier
2021-07-19 15:56 ` Quentin Perret
2021-07-19 10:47 ` [PATCH 10/14] KVM: arm64: Enable retrieving protections attributes of PTEs Quentin Perret
2021-07-19 10:47 ` [PATCH 11/14] KVM: arm64: Expose kvm_pte_valid() helper Quentin Perret
2021-07-21 8:20 ` Fuad Tabba
2021-07-19 10:47 ` [PATCH 12/14] KVM: arm64: Refactor pkvm_pgtable locking Quentin Perret
2021-07-21 8:37 ` Fuad Tabba
2021-07-19 10:47 ` [PATCH 13/14] KVM: arm64: Restrict hyp stage-1 manipulation in protected mode Quentin Perret
2021-07-21 10:45 ` Fuad Tabba
2021-07-21 13:35 ` Quentin Perret
2021-07-19 10:47 ` Quentin Perret [this message]
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