• Paolo Bonzini's avatar
    KVM: fix KVM_CLEAR_DIRTY_LOG for memory slots of unaligned size · 76d58e0f
    Paolo Bonzini authored
    If a memory slot's size is not a multiple of 64 pages (256K), then
    the KVM_CLEAR_DIRTY_LOG API is unusable: clearing the final 64 pages
    either requires the requested page range to go beyond memslot->npages,
    or requires log->num_pages to be unaligned, and kvm_clear_dirty_log_protect
    requires log->num_pages to be both in range and aligned.
    
    To allow this case, allow log->num_pages not to be a multiple of 64 if
    it ends exactly on the last page of the slot.
    Reported-by: default avatarPeter Xu <peterx@redhat.com>
    Fixes: 98938aa8 ("KVM: validate userspace input in kvm_clear_dirty_log_protect()", 2019-01-02)
    Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
    76d58e0f
kvm_main.c 99.7 KB