AArch64 EL2 hypervisor for QEMU virt that boots at EL2
Constrain register emulation with explicit architectural masks
author
vm.fail
date
(May 24, 2026, 9:18 PM UTC)
commit
b44ebfb3
b44ebfb3b5be323b540f649ccf2a1a3a9ea6e6cc
parent
2973835d
2973835d98d0aa22482139c7607af7c2309806ae
vm.fail
date
(May 24, 2026, 9:18 PM UTC)
commit
b44ebfb3
b44ebfb3b5be323b540f649ccf2a1a3a9ea6e6cc
parent
2973835d
2973835d98d0aa22482139c7607af7c2309806ae
+11
-2
+11
-2
core/policy.c
+11
-2
core/policy.c
···
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return true;
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}
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+
static uint64_t policy_mask_value(const struct policy_entry *entry, uint64_t current, uint64_t operand)
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{
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uint64_t preserve = current & ~entry->writable_mask;
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if (preserve == 0u) {
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preserve = entry->reset_value & ~entry->writable_mask;
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}
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return preserve | (operand & entry->writable_mask);
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}
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+
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void policy_init(void)
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{
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g_profile = POLICY_PROFILE_STRICT;
···
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decision->action = POLICY_DENY_UNDEF;
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return true;
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}
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-
*slot = operand & entry->writable_mask;
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*slot = policy_mask_value(entry, *slot, operand);
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decision->value = *slot;
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if (g_profile == POLICY_PROFILE_LINUX_BOOT && is_el1_mmu_key(access->key)) {
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arch_sync_el1_sysregs(vcpu);
···
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decision->action = POLICY_DENY_UNDEF;
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return true;
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}
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-
*slot = (*slot & ~entry->writable_mask) | (operand & entry->writable_mask);
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*slot = policy_mask_value(entry, *slot, operand);
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decision->value = *slot;
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if (g_profile == POLICY_PROFILE_LINUX_BOOT && is_el1_mmu_key(access->key)) {
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arch_sync_el1_sysregs(vcpu);