KVM: Fix the bitmap range to copy during clear dirty

kvm_dirty_bitmap_bytes() will return the size of the dirty bitmap of
the memslot rather than the size of bitmap passed over from the ioctl.
Here for KVM_CLEAR_DIRTY_LOG we should only copy exactly the size of
bitmap that covers kvm_clear_dirty_log.num_pages.

Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 2a31b9db15
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Peter Xu 2019-05-08 17:15:45 +08:00 committed by Paolo Bonzini
parent e9c16c7850
commit 4ddc920457

View File

@ -1251,7 +1251,7 @@ int kvm_clear_dirty_log_protect(struct kvm *kvm,
if (!dirty_bitmap)
return -ENOENT;
n = kvm_dirty_bitmap_bytes(memslot);
n = ALIGN(log->num_pages, BITS_PER_LONG) / 8;
if (log->first_page > memslot->npages ||
log->num_pages > memslot->npages - log->first_page ||