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|
$NetBSD: patch-CVE-2013-1918_11,v 1.1 2013/05/03 16:48:37 drochner Exp $
--- xen/arch/x86/domain.c.orig 2013-05-03 13:27:23.000000000 +0000
+++ xen/arch/x86/domain.c
@@ -70,8 +70,6 @@ void (*dead_idle) (void) __read_mostly =
static void paravirt_ctxt_switch_from(struct vcpu *v);
static void paravirt_ctxt_switch_to(struct vcpu *v);
-static void vcpu_destroy_pagetables(struct vcpu *v);
-
static void continue_idle_domain(struct vcpu *v)
{
reset_stack_and_jump(idle_loop);
@@ -678,6 +676,7 @@ int arch_set_info_guest(
{
struct domain *d = v->domain;
unsigned long cr3_pfn = INVALID_MFN;
+ struct page_info *cr3_page;
unsigned long flags, cr4;
int i, rc = 0, compat;
@@ -817,72 +816,103 @@ int arch_set_info_guest(
if ( rc != 0 )
return rc;
+ set_bit(_VPF_in_reset, &v->pause_flags);
+
if ( !compat )
- {
cr3_pfn = gmfn_to_mfn(d, xen_cr3_to_pfn(c.nat->ctrlreg[3]));
+#ifdef __x86_64__
+ else
+ cr3_pfn = gmfn_to_mfn(d, compat_cr3_to_pfn(c.cmp->ctrlreg[3]));
+#endif
+ cr3_page = mfn_to_page(cr3_pfn);
- if ( !mfn_valid(cr3_pfn) ||
- (paging_mode_refcounts(d)
- ? !get_page(mfn_to_page(cr3_pfn), d)
- : !get_page_and_type(mfn_to_page(cr3_pfn), d,
- PGT_base_page_table)) )
- {
- destroy_gdt(v);
- return -EINVAL;
- }
+ if ( !mfn_valid(cr3_pfn) || !get_page(cr3_page, d) )
+ {
+ cr3_page = NULL;
+ rc = -EINVAL;
+ }
+ else if ( paging_mode_refcounts(d) )
+ /* nothing */;
+ else if ( cr3_page == v->arch.old_guest_table )
+ {
+ v->arch.old_guest_table = NULL;
+ put_page(cr3_page);
+ }
+ else
+ {
+ /*
+ * Since v->arch.guest_table{,_user} are both NULL, this effectively
+ * is just a call to put_old_guest_table().
+ */
+ if ( !compat )
+ rc = vcpu_destroy_pagetables(v);
+ if ( !rc )
+ rc = get_page_type_preemptible(cr3_page,
+ !compat ? PGT_root_page_table
+ : PGT_l3_page_table);
+ if ( rc == -EINTR )
+ rc = -EAGAIN;
+ }
+ if ( rc )
+ /* handled below */;
+ else if ( !compat )
+ {
v->arch.guest_table = pagetable_from_pfn(cr3_pfn);
#ifdef __x86_64__
if ( c.nat->ctrlreg[1] )
{
cr3_pfn = gmfn_to_mfn(d, xen_cr3_to_pfn(c.nat->ctrlreg[1]));
+ cr3_page = mfn_to_page(cr3_pfn);
- if ( !mfn_valid(cr3_pfn) ||
- (paging_mode_refcounts(d)
- ? !get_page(mfn_to_page(cr3_pfn), d)
- : !get_page_and_type(mfn_to_page(cr3_pfn), d,
- PGT_base_page_table)) )
+ if ( !mfn_valid(cr3_pfn) || !get_page(cr3_page, d) )
{
- cr3_pfn = pagetable_get_pfn(v->arch.guest_table);
- v->arch.guest_table = pagetable_null();
- if ( paging_mode_refcounts(d) )
- put_page(mfn_to_page(cr3_pfn));
- else
- put_page_and_type(mfn_to_page(cr3_pfn));
- destroy_gdt(v);
- return -EINVAL;
+ cr3_page = NULL;
+ rc = -EINVAL;
+ }
+ else if ( !paging_mode_refcounts(d) )
+ {
+ rc = get_page_type_preemptible(cr3_page, PGT_root_page_table);
+ switch ( rc )
+ {
+ case -EINTR:
+ rc = -EAGAIN;
+ case -EAGAIN:
+ v->arch.old_guest_table =
+ pagetable_get_page(v->arch.guest_table);
+ v->arch.guest_table = pagetable_null();
+ break;
+ }
}
- v->arch.guest_table_user = pagetable_from_pfn(cr3_pfn);
+ if ( !rc )
+ v->arch.guest_table_user = pagetable_from_pfn(cr3_pfn);
}
else if ( !(flags & VGCF_in_kernel) )
{
- destroy_gdt(v);
- return -EINVAL;
+ cr3_page = NULL;
+ rc = -EINVAL;
}
}
else
{
l4_pgentry_t *l4tab;
- cr3_pfn = gmfn_to_mfn(d, compat_cr3_to_pfn(c.cmp->ctrlreg[3]));
-
- if ( !mfn_valid(cr3_pfn) ||
- (paging_mode_refcounts(d)
- ? !get_page(mfn_to_page(cr3_pfn), d)
- : !get_page_and_type(mfn_to_page(cr3_pfn), d,
- PGT_l3_page_table)) )
- {
- destroy_gdt(v);
- return -EINVAL;
- }
-
l4tab = __va(pagetable_get_paddr(v->arch.guest_table));
*l4tab = l4e_from_pfn(
cr3_pfn, _PAGE_PRESENT|_PAGE_RW|_PAGE_USER|_PAGE_ACCESSED);
#endif
}
+ if ( rc )
+ {
+ if ( cr3_page )
+ put_page(cr3_page);
+ destroy_gdt(v);
+ return rc;
+ }
+
+ clear_bit(_VPF_in_reset, &v->pause_flags);
if ( v->vcpu_id == 0 )
update_domain_wallclock_time(d);
@@ -904,17 +934,16 @@ int arch_set_info_guest(
#undef c
}
-void arch_vcpu_reset(struct vcpu *v)
+int arch_vcpu_reset(struct vcpu *v)
{
if ( !is_hvm_vcpu(v) )
{
destroy_gdt(v);
- vcpu_destroy_pagetables(v);
- }
- else
- {
- vcpu_end_shutdown_deferral(v);
+ return vcpu_destroy_pagetables(v);
}
+
+ vcpu_end_shutdown_deferral(v);
+ return 0;
}
/*
@@ -1917,63 +1946,6 @@ static int relinquish_memory(
return ret;
}
-static void vcpu_destroy_pagetables(struct vcpu *v)
-{
- struct domain *d = v->domain;
- unsigned long pfn;
-
-#ifdef __x86_64__
- if ( is_pv_32on64_vcpu(v) )
- {
- pfn = l4e_get_pfn(*(l4_pgentry_t *)
- __va(pagetable_get_paddr(v->arch.guest_table)));
-
- if ( pfn != 0 )
- {
- if ( paging_mode_refcounts(d) )
- put_page(mfn_to_page(pfn));
- else
- put_page_and_type(mfn_to_page(pfn));
- }
-
- l4e_write(
- (l4_pgentry_t *)__va(pagetable_get_paddr(v->arch.guest_table)),
- l4e_empty());
-
- v->arch.cr3 = 0;
- return;
- }
-#endif
-
- pfn = pagetable_get_pfn(v->arch.guest_table);
- if ( pfn != 0 )
- {
- if ( paging_mode_refcounts(d) )
- put_page(mfn_to_page(pfn));
- else
- put_page_and_type(mfn_to_page(pfn));
- v->arch.guest_table = pagetable_null();
- }
-
-#ifdef __x86_64__
- /* Drop ref to guest_table_user (from MMUEXT_NEW_USER_BASEPTR) */
- pfn = pagetable_get_pfn(v->arch.guest_table_user);
- if ( pfn != 0 )
- {
- if ( !is_pv_32bit_vcpu(v) )
- {
- if ( paging_mode_refcounts(d) )
- put_page(mfn_to_page(pfn));
- else
- put_page_and_type(mfn_to_page(pfn));
- }
- v->arch.guest_table_user = pagetable_null();
- }
-#endif
-
- v->arch.cr3 = 0;
-}
-
int domain_relinquish_resources(struct domain *d)
{
int ret;
@@ -1992,7 +1964,9 @@ int domain_relinquish_resources(struct d
for_each_vcpu ( d, v )
{
/* Drop the in-use references to page-table bases. */
- vcpu_destroy_pagetables(v);
+ ret = vcpu_destroy_pagetables(v);
+ if ( ret )
+ return ret;
/*
* Relinquish GDT mappings. No need for explicit unmapping of the
|
