Daniel De Graaf
2013-Mar-27 17:43 UTC
[PATCH] xen/arch/x86: remove IS_PRIV access check bypasses
Several domctl functions dealing with rangesets contain a short-circuit
bypass if the domain is privileged. Since the construction of domain 0
permits access to all I/O ranges, the call to irq_access_permitted will
normally return true even without the IS_PRIV check, and the presence of
the IS_PRIV check prevents the creation of a privileged domain without
access to specific devices or IO memory ranges.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
---
xen/arch/x86/domctl.c | 12 ++++--------
xen/arch/x86/irq.c | 3 +--
2 files changed, 5 insertions(+), 10 deletions(-)
diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
index a196e2a..327a792 100644
--- a/xen/arch/x86/domctl.c
+++ b/xen/arch/x86/domctl.c
@@ -578,8 +578,7 @@ long arch_do_domctl(
break;
ret = -EPERM;
- if ( !IS_PRIV(current->domain) &&
- !irq_access_permitted(current->domain, bind->machine_irq) )
+ if ( !irq_access_permitted(current->domain, bind->machine_irq) )
break;
ret = -ESRCH;
@@ -602,8 +601,7 @@ long arch_do_domctl(
bind = &(domctl->u.bind_pt_irq);
ret = -EPERM;
- if ( !IS_PRIV(current->domain) &&
- !irq_access_permitted(current->domain, bind->machine_irq) )
+ if ( !irq_access_permitted(current->domain, bind->machine_irq) )
break;
ret = xsm_unbind_pt_irq(XSM_HOOK, d, bind);
@@ -637,8 +635,7 @@ long arch_do_domctl(
break;
ret = -EPERM;
- if ( !IS_PRIV(current->domain) &&
- !iomem_access_permitted(current->domain, mfn, mfn + nr_mfns -
1) )
+ if ( !iomem_access_permitted(current->domain, mfn, mfn + nr_mfns -
1) )
break;
ret = xsm_iomem_mapping(XSM_HOOK, d, mfn, mfn + nr_mfns - 1, add);
@@ -715,8 +712,7 @@ long arch_do_domctl(
}
ret = -EPERM;
- if ( !IS_PRIV(current->domain) &&
- !ioports_access_permitted(current->domain, fmp, fmp + np - 1) )
+ if ( !ioports_access_permitted(current->domain, fmp, fmp + np - 1) )
break;
ret = xsm_ioport_mapping(XSM_HOOK, d, fmp, fmp + np - 1, add);
diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c
index ca829bb..17a3174 100644
--- a/xen/arch/x86/irq.c
+++ b/xen/arch/x86/irq.c
@@ -1852,8 +1852,7 @@ int map_domain_pirq(
ASSERT(spin_is_locked(&d->event_lock));
- if ( !IS_PRIV(current->domain) &&
- !irq_access_permitted(current->domain, pirq))
+ if ( !irq_access_permitted(current->domain, pirq))
return -EPERM;
if ( pirq < 0 || pirq >= d->nr_pirqs || irq < 0 || irq >=
nr_irqs )
--
1.8.1.4