Given the following code containing errors, provide Common Weakness Enumeration (CWE) identifiers and corresponding messages in JSON format. Each identified weakness should have a unique entry in the JSON array.
    Code: 
static void kvm_invalidate_memslot(struct kvm *kvm,
				   struct kvm_memory_slot *old,
				   struct kvm_memory_slot *invalid_slot)
{
	/*
	 * Mark the current slot INVALID.  As with all memslot modifications,
	 * this must be done on an unreachable slot to avoid modifying the
	 * current slot in the active tree.
	 */
	kvm_copy_memslot(invalid_slot, old);
	invalid_slot->flags |= KVM_MEMSLOT_INVALID;
	kvm_replace_memslot(kvm, old, invalid_slot);

	/*
	 * Activate the slot that is now marked INVALID, but don't propagate
	 * the slot to the now inactive slots. The slot is either going to be
	 * deleted or recreated as a new slot.
	 */
	kvm_swap_active_memslots(kvm, old->as_id);

	/*
	 * From this point no new shadow pages pointing to a deleted, or moved,
	 * memslot will be created.  Validation of sp->gfn happens in:
	 *	- gfn_to_hva (kvm_read_guest, gfn_to_pfn)
	 *	- kvm_is_visible_gfn (mmu_check_root)
	 */
	kvm_arch_flush_shadow_memslot(kvm, old);

	/* Was released by kvm_swap_active_memslots, reacquire. */
	mutex_lock(&kvm->slots_arch_lock);

	/*
	 * Copy the arch-specific field of the newly-installed slot back to the
	 * old slot as the arch data could have changed between releasing
	 * slots_arch_lock in install_new_memslots() and re-acquiring the lock
	 * above.  Writers are required to retrieve memslots *after* acquiring
	 * slots_arch_lock, thus the active slot's data is guaranteed to be fresh.
	 */
	old->arch = invalid_slot->arch; ; Sample JSON Format Confermily Expected output: "examples" => "cwe": "xxx"; "message": "xxx"
    
 'cwe': ['CWE-459'], 'message': 'KVM: SEV: add cache flush to solve SEV cache incoherency issues

Flush the CPU caches when memory is reclaimed from an SEV guest (where
reclaim also includes it being unmapped from KVM's memslots).  Due to lack
of coherency for SEV encrypted memory, failure to flush results in silent
data corruption if userspace is malicious/broken and doesn't ensure SEV
guest memory is properly pinned and unpinned.

Cache coherency is not enforced across the VM boundary in SEV (AMD APM
vol.2 Section 15.34.7). Confidential cachelines, generated by confidential
VM guests have to be explicitly flushed on the host side. If a memory page
containing dirty confidential cachelines was released by VM and reallocated
to another user, the cachelines may corrupt the new user at a later time.

KVM takes a shortcut by assuming all confidential memory remain pinned
until the end of VM lifetime. Therefore, KVM does not flush cache at
mmu_notifier invalidation events. Because of this incorrect assumption and
the lack of cache flushing, malicous userspace can crash the host kernel:
creating a malicious VM and continuously allocates/releases unpinned
confidential memory pages when the VM is running.

Add cache flush operations to mmu_notifier operations to ensure that any
physical memory leaving the guest VM get flushed. In particular, hook
mmu_notifier_invalidate_range_start and mmu_notifier_release events and
flush cache accordingly. The hook after releasing the mmu lock to avoid
contention with other vCPUs.

Cc: stable@vger.kernel.org
Suggested-by: Sean Christpherson <seanjc@google.com>
Reported-by: Mingwei Zhang <mizhang@google.com>
Signed-off-by: Mingwei Zhang <mizhang@google.com>
Message-Id: <20220421031407.2516575-4-mizhang@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>'