KVM: Fix kvm_clear_dirty_log_protect off-by-(minus-)one (53eac7a8) · Commits · 戴 / test

Just imaging the case where num_pages < BITS_PER_LONG, then the loop will be skipped while it shouldn't. Signed-off-by:

Peter Xu <peterx@redhat.com> Fixes: Signed-off-by:

virt/kvm/kvm_main.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1264,8 +1264,8 @@ int kvm_clear_dirty_log_protect(struct kvm *kvm,
		return -EFAULT;

		spin_lock(&kvm->mmu_lock);
		for (offset = log->first_page,
		i = offset / BITS_PER_LONG, n = log->num_pages / BITS_PER_LONG; n--;
		for (offset = log->first_page, i = offset / BITS_PER_LONG,
		n = DIV_ROUND_UP(log->num_pages, BITS_PER_LONG); n--;
		i++, offset += BITS_PER_LONG) {
		unsigned long mask = *dirty_bitmap_buffer++;
		atomic_long_t p = (atomic_long_t ) &dirty_bitmap[i];