1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
$NetBSD: patch-CVE-2015-7835,v 1.1.2.2 2015/11/04 19:55:44 bsiegert Exp $
Patch for CVE-2015-7835 aka XSA-148 based on
http://xenbits.xenproject.org/xsa/xsa148-4.4.patch
--- xen/include/asm-x86/x86_32/page.h.orig 2015-10-29 20:35:24.000000000 +0100
+++ xen/include/asm-x86/x86_32/page.h 2015-10-29 20:38:02.000000000 +0100
@@ -130,7 +130,9 @@
#define BASE_DISALLOW_MASK (0xFFFFF198U & ~_PAGE_NX)
#define L1_DISALLOW_MASK (BASE_DISALLOW_MASK | _PAGE_GNTTAB)
-#define L2_DISALLOW_MASK (BASE_DISALLOW_MASK & ~_PAGE_PSE)
+#define L2_DISALLOW_MASK (unlikely(opt_allow_superpage) \
+ ? BASE_DISALLOW_MASK & ~_PAGE_PSE \
+ : BASE_DISALLOW_MASK )
#define L3_DISALLOW_MASK 0xFFFFF1FEU /* must-be-zero */
#endif /* __X86_32_PAGE_H__ */
--- xen/include/asm-x86/x86_64/page.h.orig 2015-10-29 20:35:36.000000000 +0100
+++ xen/include/asm-x86/x86_64/page.h 2015-10-29 20:37:33.000000000 +0100
@@ -167,7 +167,9 @@
#define BASE_DISALLOW_MASK (0xFF800198U & ~_PAGE_NX)
#define L1_DISALLOW_MASK (BASE_DISALLOW_MASK | _PAGE_GNTTAB)
-#define L2_DISALLOW_MASK (BASE_DISALLOW_MASK & ~_PAGE_PSE)
+#define L2_DISALLOW_MASK (unlikely(opt_allow_superpage) \
+ ? BASE_DISALLOW_MASK & ~_PAGE_PSE \
+ : BASE_DISALLOW_MASK )
#define L3_DISALLOW_MASK (BASE_DISALLOW_MASK)
#define L4_DISALLOW_MASK (BASE_DISALLOW_MASK)
--- xen/arch/x86/mm.c.orig 2015-10-29 20:30:55.000000000 +0100
+++ xen/arch/x86/mm.c 2015-10-29 20:32:56.000000000 +0100
@@ -1898,7 +1898,10 @@
}
/* Fast path for identical mapping and presence. */
- if ( !l2e_has_changed(ol2e, nl2e, _PAGE_PRESENT) )
+ if ( !l2e_has_changed(ol2e, nl2e,
+ unlikely(opt_allow_superpage)
+ ? _PAGE_PSE | _PAGE_RW | _PAGE_PRESENT
+ : _PAGE_PRESENT) )
{
adjust_guest_l2e(nl2e, d);
rc = UPDATE_ENTRY(l2, pl2e, ol2e, nl2e, pfn, vcpu, preserve_ad);
|
