Pullup ticket #5071 - requested by bouyer

sysutils/xenkernel42: security patch

Revisions pulled up:
- sysutils/xenkernel42/Makefile                                 1.22
- sysutils/xenkernel42/distinfo                                 1.20
- sysutils/xenkernel42/patches/patch-XSA-182                    1.1

-------------------------------------------------------------------
   Module Name:	pkgsrc
   Committed By:	bouyer
   Date:		Tue Jul 26 15:38:00 UTC 2016

   Modified Files:
   	pkgsrc/sysutils/xenkernel42: Makefile distinfo
   Added Files:
   	pkgsrc/sysutils/xenkernel42/patches: patch-XSA-182

   Log Message:
   Apply security patch from XSA-182. Bump PKGREVISION
   xen 4.2 is not vulnerable to XSA-183.


   To generate a diff of this commit:
   cvs rdiff -u -r1.21 -r1.22 pkgsrc/sysutils/xenkernel42/Makefile
   cvs rdiff -u -r1.19 -r1.20 pkgsrc/sysutils/xenkernel42/distinfo
   cvs rdiff -u -r0 -r1.1 pkgsrc/sysutils/xenkernel42/patches/patch-XSA-182

3 files changed, 95 insertions, 3 deletions

diff --git a/sysutils/xenkernel42/Makefile b/sysutils/xenkernel42/Makefile
index 2eacc900ffc..8a575a0c316 100644
--- a/sysutils/xenkernel42/Makefile
+++ b/sysutils/xenkernel42/Makefile
@@ -1,9 +1,9 @@
-# $NetBSD: Makefile,v 1.20 2016/01/07 17:53:58 bouyer Exp $
+# $NetBSD: Makefile,v 1.20.4.1 2016/07/28 13:54:43 spz Exp $
 
 VERSION=	4.2.5
 DISTNAME=	xen-${VERSION}
 PKGNAME=	xenkernel42-${VERSION}
-PKGREVISION=	10
+PKGREVISION=	11
 CATEGORIES=	sysutils
 MASTER_SITES=	http://bits.xensource.com/oss-xen/release/${VERSION}/
 
diff --git a/sysutils/xenkernel42/distinfo b/sysutils/xenkernel42/distinfo
index d6b758c003f..2ba35a79032 100644
--- a/sysutils/xenkernel42/distinfo
+++ b/sysutils/xenkernel42/distinfo
@@ -1,4 +1,4 @@
-$NetBSD: distinfo,v 1.19 2016/01/07 17:53:58 bouyer Exp $
+$NetBSD: distinfo,v 1.19.4.1 2016/07/28 13:54:43 spz Exp $
 
 SHA1 (xen-4.2.5.tar.gz) = f42741e4ec174495ace70c4b17a6b9b0e60e798a
 RMD160 (xen-4.2.5.tar.gz) = 7d4f7f1b32ee541d341a756b1f8da02816438d19
@@ -26,6 +26,7 @@ SHA1 (patch-CVE-2015-8339) = 080bc4c04ee5ad832756b11a65b1598f12eae97e
 SHA1 (patch-CVE-2015-8555) = 594f85557efe137fb32a88c0dc589a1318184b66
 SHA1 (patch-Config.mk) = a43ed1b3304d6383dc093acd128a7f373d0ca266
 SHA1 (patch-XSA-166) = 24fccf8e30ccf910a128e5e0365800191a90524c
+SHA1 (patch-XSA-182) = f0325a6f7c7cc20c3f11367384628dbe25c90b2d
 SHA1 (patch-xen_Makefile) = e0d1b74518b9675ddc64295d1523ded9a8757c0a
 SHA1 (patch-xen_arch_x86_Rules.mk) = 6b9b4bfa28924f7d3f6c793a389f1a7ac9d228e2
 SHA1 (patch-xen_arch_x86_hvm_hvm.c) = b6bac1d466ba5bc276bc3aea9d4c9df37f2b9b0f
diff --git a/sysutils/xenkernel42/patches/patch-XSA-182 b/sysutils/xenkernel42/patches/patch-XSA-182
new file mode 100644
index 00000000000..50da8b26b11
--- /dev/null
+++ b/sysutils/xenkernel42/patches/patch-XSA-182
@@ -0,0 +1,91 @@
+$NetBSD: patch-XSA-182,v 1.1.2.2 2016/07/28 13:54:43 spz Exp $
+
+backported from:
+
+From 798c1498f764bfaa7b0b955bab40b01b0610d372 Mon Sep 17 00:00:00 2001
+From: Andrew Cooper <andrew.cooper3@citrix.com>
+Date: Mon, 11 Jul 2016 14:32:03 +0100
+Subject: [PATCH] x86/pv: Remove unsafe bits from the mod_l?_entry() fastpath
+
+All changes in writeability and cacheability must go through full
+re-validation.
+
+Rework the logic as a whitelist, to make it clearer to follow.
+
+This is XSA-182
+
+--- xen/arch/x86/mm.c.orig	2016-07-26 16:33:46.000000000 +0200
++++ xen/arch/x86/mm.c	2016-07-26 16:37:14.000000000 +0200
+@@ -1860,6 +1860,14 @@
+                   _t ## e_get_intpte(_o), _t ## e_get_intpte(_n),   \
+                   (_m), (_v), (_ad))
+ 
++/*
++ * PTE flags that a guest may change without re-validating the PTE.
++ * All other bits affect translation, caching, or Xen's safety.
++ */
++#define FASTPATH_FLAG_WHITELIST                                     \
++    (_PAGE_NX_BIT | _PAGE_AVAIL_HIGH | _PAGE_AVAIL | _PAGE_GLOBAL | \
++     _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_USER)
++
+ /* Update the L1 entry at pl1e to new value nl1e. */
+ static int mod_l1_entry(l1_pgentry_t *pl1e, l1_pgentry_t nl1e,
+                         unsigned long gl1mfn, int preserve_ad,
+@@ -1900,8 +1908,8 @@
+             return -EINVAL;
+         }
+ 
+-        /* Fast path for identical mapping, r/w and presence. */
+-        if ( !l1e_has_changed(ol1e, nl1e, _PAGE_RW | _PAGE_PRESENT) )
++        /* Fast path for sufficiently-similar mappings.*/
++        if ( !l1e_has_changed(ol1e, nl1e, ~FASTPATH_FLAG_WHITELIST) )
+         {
+             adjust_guest_l1e(nl1e, pt_dom);
+             if ( UPDATE_ENTRY(l1, pl1e, ol1e, nl1e, gl1mfn, pt_vcpu,
+@@ -1982,11 +1990,8 @@
+             return -EINVAL;
+         }
+ 
+-        /* Fast path for identical mapping and presence. */
+-        if ( !l2e_has_changed(ol2e, nl2e,
+-                              unlikely(opt_allow_superpage)
+-                              ? _PAGE_PSE | _PAGE_RW | _PAGE_PRESENT
+-                              : _PAGE_PRESENT) )
++        /* Fast path for sufficiently-similar mappings. */
++        if ( !l2e_has_changed(ol2e, nl2e, ~FASTPATH_FLAG_WHITELIST) )
+         {
+             adjust_guest_l2e(nl2e, d);
+             if ( UPDATE_ENTRY(l2, pl2e, ol2e, nl2e, pfn, vcpu, preserve_ad) )
+@@ -2051,8 +2056,8 @@
+             return -EINVAL;
+         }
+ 
+-        /* Fast path for identical mapping and presence. */
+-        if ( !l3e_has_changed(ol3e, nl3e, _PAGE_PRESENT) )
++        /* Fast path for sufficiently-similar mappings. */
++        if ( !l3e_has_changed(ol3e, nl3e, ~FASTPATH_FLAG_WHITELIST) )
+         {
+             adjust_guest_l3e(nl3e, d);
+             rc = UPDATE_ENTRY(l3, pl3e, ol3e, nl3e, pfn, vcpu, preserve_ad);
+@@ -2121,8 +2126,8 @@
+             return -EINVAL;
+         }
+ 
+-        /* Fast path for identical mapping and presence. */
+-        if ( !l4e_has_changed(ol4e, nl4e, _PAGE_PRESENT) )
++        /* Fast path for sufficiently-similar mappings. */
++        if ( !l4e_has_changed(ol4e, nl4e, ~FASTPATH_FLAG_WHITELIST) )
+         {
+             adjust_guest_l4e(nl4e, d);
+             rc = UPDATE_ENTRY(l4, pl4e, ol4e, nl4e, pfn, vcpu, preserve_ad);
+
+--- xen/include/asm-x86/page.h.orig	2014-09-02 08:22:57.000000000 +0200
++++ xen/include/asm-x86/page.h	2016-07-26 16:39:51.000000000 +0200
+@@ -332,6 +332,7 @@
+ #define _PAGE_AVAIL2   0x800U
+ #define _PAGE_AVAIL    0xE00U
+ #define _PAGE_PSE_PAT 0x1000U
++#define _PAGE_AVAIL_HIGH (0x7ffU << 12)
+ #define _PAGE_PAGED   0x2000U
+ #define _PAGE_SHARED  0x4000U
+