On Tue, Jun 5, 2018 at 10:16 AM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: > On Mon, May 28, 2018 at 1:25 PM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: >> On 26/05/2018 11:29, Dmitry Vyukov wrote: >>> KASAN: stack-out-of-bounds Read in do_general_protection >>> KASAN: slab-out-of-bounds Read in vmx_vcpu_run >>> KASAN: use-after-scope Read in vmx_vcpu_run >>> KASAN: stack-out-of-bounds Write in notify_die >>> >>> See full info at: >>> https://syzkaller.appspot.com/bug?extid=a1264132fc103340628f >>> >>> >>> There seems to be 2 problems: >>> >>> 1. msr_write_intercepted doing something notoriously bad. >> >> The faulting line is >> >> msr_bitmap = to_vmx(vcpu)->loaded_vmcs->msr_bitmap; >> >> so I suppose to_vmx(vcpu)->loaded_vmcs is bogus? That seems like "just" >> a corruption of the struct kvm_vcpu, because the loaded_vmcs field is >> pointing elsewhere inside the same struct. > > This is reproducible and the reproducer only uses KVM syscalls. So it > seems that KVM corrupts itself. Perhaps it's KVM_SET_MSRS that messes > things? This one looks like the same root cause as here: KASAN: stack-out-of-bounds Read in unwind_next_frame https://groups.google.com/d/msg/syzkaller-bugs/MGQ_W8DPYXA/k-xK7sBrBgAJ
