On Tue, Feb 23, 2016 at 3:30 PM, Paolo Bonzini <[email protected]> wrote: > > > On 15/01/2016 18:02, Sasha Levin wrote: >> Hi all, >> >> While fuzzing with syzkaller on the latest -next kernel running on a KVM >> tools >> guest, I've hit the following use of an uninitialized variable: >> >> [ 810.783676] UBSAN: Undefined behaviour in arch/x86/kvm/mmu.c:3502:6 >> >> [ 810.785650] load of value 179 is not a valid value for type '_Bool' > > Can you check this patch: > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index be3cef12706c..fd54613a1204 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -1449,8 +1449,11 @@ pfn_t __gfn_to_pfn_memslot(struct > if (addr == KVM_HVA_ERR_RO_BAD) > return KVM_PFN_ERR_RO_FAULT; > > - if (kvm_is_error_hva(addr)) > + if (kvm_is_error_hva(addr)) { > + if (writable) > + *writable = false; > return KVM_PFN_NOSLOT; > + } > > /* Do not map writable pfn in the readonly memslot. */ > if (writable && memslot_is_readonly(slot)) {
Sasha, does it fix the issue? This patch is still not merged.
