Commit 871c433b authored by Rustam Kovhaev's avatar Rustam Kovhaev Committed by Paolo Bonzini
Browse files

KVM: use struct_size() and flex_array_size() helpers in kvm_io_bus_unregister_dev() 



Make use of the struct_size() helper to avoid any potential type
mistakes and protect against potential integer overflows
Make use of the flex_array_size() helper to calculate the size of a
flexible array member within an enclosing structure

Suggested-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: default avatarRustam Kovhaev <rkovhaev@gmail.com>
Message-Id: <20200918120500.954436-1-rkovhaev@gmail.com>
Reviewed-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 4407a797

virt/kvm/kvm_main.c

+2 −2
Original line number Diff line number Diff line
@@ -4350,10 +4350,10 @@ void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, 
	new_bus = kmalloc(struct_size(bus, range, bus->dev_count - 1),

			  GFP_KERNEL_ACCOUNT);

	if (new_bus) {

		memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));

		memcpy(new_bus, bus, struct_size(bus, range, i));

		new_bus->dev_count--;

		memcpy(new_bus->range + i, bus->range + i + 1,

		       (new_bus->dev_count - i) * sizeof(struct kvm_io_range));

				flex_array_size(new_bus, range, new_bus->dev_count - i));

	} else {

		pr_err("kvm: failed to shrink bus, removing it completely\n");

		for (j = 0; j < bus->dev_count; j++) {