On Tue, Dec 15, 2015 at 11:23 AM, Christian Borntraeger
<borntraeger@xxxxxxxxxx> wrote:
> The s390dbf and trace events provide a debugfs interface.
> If kptr_restrict is active, we should not expose kernel
> pointers. We can fence the debugfs output by using %pK
> instead of %p.
>
> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> Reviewed-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx>
> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Nice catch, thanks!
Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>
-Kees
> ---
> arch/s390/kvm/kvm-s390.c | 9 +++++----
> arch/s390/kvm/trace-s390.h | 6 +++---
> 2 files changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 6dec01d..c14845c 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -1185,7 +1185,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
> kvm->arch.epoch = 0;
>
> spin_lock_init(&kvm->arch.start_stop_lock);
> - KVM_EVENT(3, "vm 0x%p created by pid %u", kvm, current->pid);
> + KVM_EVENT(3, "vm 0x%pK created by pid %u", kvm, current->pid);
>
> return 0;
> out_err:
> @@ -1245,7 +1245,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
> gmap_free(kvm->arch.gmap);
> kvm_s390_destroy_adapters(kvm);
> kvm_s390_clear_float_irqs(kvm);
> - KVM_EVENT(3, "vm 0x%p destroyed", kvm);
> + KVM_EVENT(3, "vm 0x%pK destroyed", kvm);
> }
>
> /* Section: vcpu related */
> @@ -1349,7 +1349,8 @@ static int sca_switch_to_extended(struct kvm *kvm)
>
> free_page((unsigned long)old_sca);
>
> - VM_EVENT(kvm, 2, "Switched to ESCA (%p -> %p)", old_sca, kvm->arch.sca);
> + VM_EVENT(kvm, 2, "Switched to ESCA (0x%pK -> 0x%pK)",
> + old_sca, kvm->arch.sca);
> return 0;
> }
>
> @@ -1624,7 +1625,7 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
> rc = kvm_vcpu_init(vcpu, kvm, id);
> if (rc)
> goto out_free_sie_block;
> - VM_EVENT(kvm, 3, "create cpu %d at %p, sie block at %p", id, vcpu,
> + VM_EVENT(kvm, 3, "create cpu %d at 0x%pK, sie block at 0x%pK", id, vcpu,
> vcpu->arch.sie_block);
> trace_kvm_s390_create_vcpu(id, vcpu, vcpu->arch.sie_block);
>
> diff --git a/arch/s390/kvm/trace-s390.h b/arch/s390/kvm/trace-s390.h
> index cc1d6c6..396485b 100644
> --- a/arch/s390/kvm/trace-s390.h
> +++ b/arch/s390/kvm/trace-s390.h
> @@ -55,8 +55,8 @@ TRACE_EVENT(kvm_s390_create_vcpu,
> __entry->sie_block = sie_block;
> ),
>
> - TP_printk("create cpu %d at %p, sie block at %p", __entry->id,
> - __entry->vcpu, __entry->sie_block)
> + TP_printk("create cpu %d at 0x%pK, sie block at 0x%pK",
> + __entry->id, __entry->vcpu, __entry->sie_block)
> );
>
> TRACE_EVENT(kvm_s390_destroy_vcpu,
> @@ -254,7 +254,7 @@ TRACE_EVENT(kvm_s390_enable_css,
> __entry->kvm = kvm;
> ),
>
> - TP_printk("enabling channel I/O support (kvm @ %p)\n",
> + TP_printk("enabling channel I/O support (kvm @ %pK)\n",
> __entry->kvm)
> );
>
> --
> 2.3.0
>
--
Kees Cook
Chrome OS & Brillo Security
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
