system/xen: Updated for version 4.6.1.

Signed-off-by: Mario Preksavec <mario@slackware.hr>

8 files changed, 734 insertions, 0 deletions

diff --git a/system/xen/patches/xsa173-4.6.patch b/system/xen/patches/xsa173-4.6.patch
new file mode 100644
index 000000000000..aecf120c74fd
--- /dev/null
+++ b/system/xen/patches/xsa173-4.6.patch
@@ -0,0 +1,244 @@
+commit 54a4651cb4e744960fb375ed99909d7dfb943caf
+Author: Tim Deegan <tim@xen.org>
+Date:   Wed Mar 16 16:51:27 2016 +0000
+
+    x86: limit GFNs to 32 bits for shadowed superpages.
+    
+    Superpage shadows store the shadowed GFN in the backpointer field,
+    which for non-BIGMEM builds is 32 bits wide.  Shadowing a superpage
+    mapping of a guest-physical address above 2^44 would lead to the GFN
+    being truncated there, and a crash when we come to remove the shadow
+    from the hash table.
+    
+    Track the valid width of a GFN for each guest, including reporting it
+    through CPUID, and enforce it in the shadow pagetables.  Set the
+    maximum witth to 32 for guests where this truncation could occur.
+    
+    This is XSA-173.
+    
+    Signed-off-by: Tim Deegan <tim@xen.org>
+    Signed-off-by: Jan Beulich <jbeulich@suse.com>
+
+Reported-by: Ling Liu <liuling-it@360.cn>
+diff --git a/xen/arch/x86/cpu/common.c b/xen/arch/x86/cpu/common.c
+index 35ef21b..528c283 100644
+--- a/xen/arch/x86/cpu/common.c
++++ b/xen/arch/x86/cpu/common.c
+@@ -38,6 +38,7 @@ integer_param("cpuid_mask_ext_edx", opt_cpuid_mask_ext_edx);
+ const struct cpu_dev *__read_mostly cpu_devs[X86_VENDOR_NUM] = {};
+ 
+ unsigned int paddr_bits __read_mostly = 36;
++unsigned int hap_paddr_bits __read_mostly = 36;
+ 
+ /*
+  * Default host IA32_CR_PAT value to cover all memory types.
+@@ -211,7 +212,7 @@ static void __init early_cpu_detect(void)
+ 
+ static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
+ {
+-	u32 tfms, capability, excap, ebx;
++	u32 tfms, capability, excap, ebx, eax;
+ 
+ 	/* Get vendor name */
+ 	cpuid(0x00000000, &c->cpuid_level,
+@@ -248,8 +249,11 @@ static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
+ 		}
+ 		if ( c->extended_cpuid_level >= 0x80000004 )
+ 			get_model_name(c); /* Default name */
+-		if ( c->extended_cpuid_level >= 0x80000008 )
+-			paddr_bits = cpuid_eax(0x80000008) & 0xff;
++		if ( c->extended_cpuid_level >= 0x80000008 ) {
++			eax = cpuid_eax(0x80000008);
++			paddr_bits = eax & 0xff;
++			hap_paddr_bits = ((eax >> 16) & 0xff) ?: paddr_bits;
++		}
+ 	}
+ 
+ 	/* Might lift BIOS max_leaf=3 limit. */
+diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
+index e200aab..0b4d9f0 100644
+--- a/xen/arch/x86/hvm/hvm.c
++++ b/xen/arch/x86/hvm/hvm.c
+@@ -4567,8 +4567,7 @@ void hvm_cpuid(unsigned int input, unsigned int *eax, unsigned int *ebx,
+         break;
+ 
+     case 0x80000008:
+-        count = cpuid_eax(0x80000008);
+-        count = (count >> 16) & 0xff ?: count & 0xff;
++        count = d->arch.paging.gfn_bits + PAGE_SHIFT;
+         if ( (*eax & 0xff) > count )
+             *eax = (*eax & ~0xff) | count;
+ 
+diff --git a/xen/arch/x86/mm/guest_walk.c b/xen/arch/x86/mm/guest_walk.c
+index 773454d..06543d3 100644
+--- a/xen/arch/x86/mm/guest_walk.c
++++ b/xen/arch/x86/mm/guest_walk.c
+@@ -93,6 +93,12 @@ void *map_domain_gfn(struct p2m_domain *p2m, gfn_t gfn, mfn_t *mfn,
+     struct page_info *page;
+     void *map;
+ 
++    if ( gfn_x(gfn) >> p2m->domain->arch.paging.gfn_bits )
++    {
++        *rc = _PAGE_INVALID_BIT;
++        return NULL;
++    }
++
+     /* Translate the gfn, unsharing if shared */
+     page = get_page_from_gfn_p2m(p2m->domain, p2m, gfn_x(gfn), p2mt, NULL,
+                                  q);
+@@ -326,20 +332,8 @@ guest_walk_tables(struct vcpu *v, struct p2m_domain *p2m,
+             flags &= ~_PAGE_PAT;
+ 
+         if ( gfn_x(start) & GUEST_L2_GFN_MASK & ~0x1 )
+-        {
+-#if GUEST_PAGING_LEVELS == 2
+-            /*
+-             * Note that _PAGE_INVALID_BITS is zero in this case, yielding a
+-             * no-op here.
+-             *
+-             * Architecturally, the walk should fail if bit 21 is set (others
+-             * aren't being checked at least in PSE36 mode), but we'll ignore
+-             * this here in order to avoid specifying a non-natural, non-zero
+-             * _PAGE_INVALID_BITS value just for that case.
+-             */
+-#endif
+             rc |= _PAGE_INVALID_BITS;
+-        }
++
+         /* Increment the pfn by the right number of 4k pages.  
+          * Mask out PAT and invalid bits. */
+         start = _gfn((gfn_x(start) & ~GUEST_L2_GFN_MASK) +
+@@ -422,5 +416,11 @@ set_ad:
+         put_page(mfn_to_page(mfn_x(gw->l1mfn)));
+     }
+ 
++    /* If this guest has a restricted physical address space then the
++     * target GFN must fit within it. */
++    if ( !(rc & _PAGE_PRESENT)
++         && gfn_x(guest_l1e_get_gfn(gw->l1e)) >> d->arch.paging.gfn_bits )
++        rc |= _PAGE_INVALID_BITS;
++
+     return rc;
+ }
+diff --git a/xen/arch/x86/mm/hap/hap.c b/xen/arch/x86/mm/hap/hap.c
+index 6eb2167..f3475c6 100644
+--- a/xen/arch/x86/mm/hap/hap.c
++++ b/xen/arch/x86/mm/hap/hap.c
+@@ -448,6 +448,8 @@ void hap_domain_init(struct domain *d)
+ {
+     INIT_PAGE_LIST_HEAD(&d->arch.paging.hap.freelist);
+ 
++    d->arch.paging.gfn_bits = hap_paddr_bits - PAGE_SHIFT;
++
+     /* Use HAP logdirty mechanism. */
+     paging_log_dirty_init(d, hap_enable_log_dirty,
+                           hap_disable_log_dirty,
+diff --git a/xen/arch/x86/mm/shadow/common.c b/xen/arch/x86/mm/shadow/common.c
+index bad8360..98d0d2c 100644
+--- a/xen/arch/x86/mm/shadow/common.c
++++ b/xen/arch/x86/mm/shadow/common.c
+@@ -51,6 +51,16 @@ int shadow_domain_init(struct domain *d, unsigned int domcr_flags)
+     INIT_PAGE_LIST_HEAD(&d->arch.paging.shadow.freelist);
+     INIT_PAGE_LIST_HEAD(&d->arch.paging.shadow.pinned_shadows);
+ 
++    d->arch.paging.gfn_bits = paddr_bits - PAGE_SHIFT;
++#ifndef CONFIG_BIGMEM
++    /*
++     * Shadowed superpages store GFNs in 32-bit page_info fields.
++     * Note that we cannot use guest_supports_superpages() here.
++     */
++    if ( !is_pv_domain(d) || opt_allow_superpage )
++        d->arch.paging.gfn_bits = 32;
++#endif
++
+     /* Use shadow pagetables for log-dirty support */
+     paging_log_dirty_init(d, sh_enable_log_dirty,
+                           sh_disable_log_dirty, sh_clean_dirty_bitmap);
+diff --git a/xen/arch/x86/mm/shadow/multi.c b/xen/arch/x86/mm/shadow/multi.c
+index 43c9488..71477fe 100644
+--- a/xen/arch/x86/mm/shadow/multi.c
++++ b/xen/arch/x86/mm/shadow/multi.c
+@@ -525,7 +525,8 @@ _sh_propagate(struct vcpu *v,
+     ASSERT(GUEST_PAGING_LEVELS > 3 || level != 3);
+ 
+     /* Check there's something for the shadows to map to */
+-    if ( !p2m_is_valid(p2mt) && !p2m_is_grant(p2mt) )
++    if ( (!p2m_is_valid(p2mt) && !p2m_is_grant(p2mt))
++         || gfn_x(target_gfn) >> d->arch.paging.gfn_bits )
+     {
+         *sp = shadow_l1e_empty();
+         goto done;
+diff --git a/xen/include/asm-x86/domain.h b/xen/include/asm-x86/domain.h
+index c6c6e71..74c3a52 100644
+--- a/xen/include/asm-x86/domain.h
++++ b/xen/include/asm-x86/domain.h
+@@ -193,6 +193,9 @@ struct paging_domain {
+     /* log dirty support */
+     struct log_dirty_domain log_dirty;
+ 
++    /* Number of valid bits in a gfn. */
++    unsigned int gfn_bits;
++
+     /* preemption handling */
+     struct {
+         const struct domain *dom;
+diff --git a/xen/include/asm-x86/guest_pt.h b/xen/include/asm-x86/guest_pt.h
+index f8a0d76..b5db401 100644
+--- a/xen/include/asm-x86/guest_pt.h
++++ b/xen/include/asm-x86/guest_pt.h
+@@ -210,15 +210,17 @@ guest_supports_nx(struct vcpu *v)
+ }
+ 
+ 
+-/* Some bits are invalid in any pagetable entry. */
+-#if GUEST_PAGING_LEVELS == 2
+-#define _PAGE_INVALID_BITS (0)
+-#elif GUEST_PAGING_LEVELS == 3
+-#define _PAGE_INVALID_BITS \
+-    get_pte_flags(((1ull<<63) - 1) & ~((1ull<<paddr_bits) - 1))
+-#else /* GUEST_PAGING_LEVELS == 4 */
++/*
++ * Some bits are invalid in any pagetable entry.
++ * Normal flags values get represented in 24-bit values (see
++ * get_pte_flags() and put_pte_flags()), so set bit 24 in
++ * addition to be able to flag out of range frame numbers.
++ */
++#if GUEST_PAGING_LEVELS == 3
+ #define _PAGE_INVALID_BITS \
+-    get_pte_flags(((1ull<<52) - 1) & ~((1ull<<paddr_bits) - 1))
++    (_PAGE_INVALID_BIT | get_pte_flags(((1ull << 63) - 1) & ~(PAGE_SIZE - 1)))
++#else /* 2-level and 4-level */
++#define _PAGE_INVALID_BITS _PAGE_INVALID_BIT
+ #endif
+ 
+ 
+diff --git a/xen/include/asm-x86/processor.h b/xen/include/asm-x86/processor.h
+index f507f5e..a200470 100644
+--- a/xen/include/asm-x86/processor.h
++++ b/xen/include/asm-x86/processor.h
+@@ -212,6 +212,8 @@ extern u32 cpuid_ext_features;
+ 
+ /* Maximum width of physical addresses supported by the hardware */
+ extern unsigned int paddr_bits;
++/* Max physical address width supported within HAP guests */
++extern unsigned int hap_paddr_bits;
+ 
+ extern const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id table[]);
+ 
+diff --git a/xen/include/asm-x86/x86_64/page.h b/xen/include/asm-x86/x86_64/page.h
+index 19ab4d0..eb5e2fd 100644
+--- a/xen/include/asm-x86/x86_64/page.h
++++ b/xen/include/asm-x86/x86_64/page.h
+@@ -141,6 +141,12 @@ typedef l4_pgentry_t root_pgentry_t;
+ #define _PAGE_GNTTAB (1U<<22)
+ 
+ /*
++ * Bit 24 of a 24-bit flag mask!  This is not any bit of a real pte,
++ * and is only used for signalling in variables that contain flags.
++ */
++#define _PAGE_INVALID_BIT (1U<<24)
++
++/*
+  * Bit 12 of a 24-bit flag mask. This corresponds to bit 52 of a pte.
+  * This is needed to distinguish between user and kernel PTEs since _PAGE_USER
+  * is asserted for both.
diff --git a/system/xen/patches/xsa176.patch b/system/xen/patches/xsa176.patch
new file mode 100644
index 000000000000..1c15abd3e333
--- /dev/null
+++ b/system/xen/patches/xsa176.patch
@@ -0,0 +1,45 @@
+x86/mm: fully honor PS bits in guest page table walks
+
+In L4 entries it is currently unconditionally reserved (and hence
+should, when set, always result in a reserved bit page fault), and is
+reserved on hardware not supporting 1Gb pages (and hence should, when
+set, similarly cause a reserved bit page fault on such hardware).
+
+This is CVE-2016-4480 / XSA-176.
+
+Signed-off-by: Jan Beulich <jbeulich@suse.com>
+Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
+
+--- a/xen/arch/x86/mm/guest_walk.c
++++ b/xen/arch/x86/mm/guest_walk.c
+@@ -226,6 +226,11 @@ guest_walk_tables(struct vcpu *v, struct
+         rc |= _PAGE_PRESENT;
+         goto out;
+     }
++    if ( gflags & _PAGE_PSE )
++    {
++        rc |= _PAGE_PSE | _PAGE_INVALID_BIT;
++        goto out;
++    }
+     rc |= ((gflags & mflags) ^ mflags);
+ 
+     /* Map the l3 table */
+@@ -247,7 +252,7 @@ guest_walk_tables(struct vcpu *v, struct
+     }
+     rc |= ((gflags & mflags) ^ mflags);
+     
+-    pse1G = (gflags & _PAGE_PSE) && guest_supports_1G_superpages(v); 
++    pse1G = !!(gflags & _PAGE_PSE);
+ 
+     if ( pse1G )
+     {
+@@ -267,6 +272,8 @@ guest_walk_tables(struct vcpu *v, struct
+             /* _PAGE_PSE_PAT not set: remove _PAGE_PAT from flags. */
+             flags &= ~_PAGE_PAT;
+ 
++        if ( !guest_supports_1G_superpages(v) )
++            rc |= _PAGE_PSE | _PAGE_INVALID_BIT;
+         if ( gfn_x(start) & GUEST_L3_GFN_MASK & ~0x1 )
+             rc |= _PAGE_INVALID_BITS;
+ 
diff --git a/system/xen/patches/xsa179-qemuu-4.6-0001-vga-fix-banked-access-bounds-checking-CVE-2016-3710.patch b/system/xen/patches/xsa179-qemuu-4.6-0001-vga-fix-banked-access-bounds-checking-CVE-2016-3710.patch
new file mode 100644
index 000000000000..3ad3cf43271e
--- /dev/null
+++ b/system/xen/patches/xsa179-qemuu-4.6-0001-vga-fix-banked-access-bounds-checking-CVE-2016-3710.patch
@@ -0,0 +1,108 @@
+From b16db5ab2d0c5ff755e08942f4c8e8f9f8618eae Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Tue, 26 Apr 2016 08:49:10 +0200
+Subject: [PATCH 1/5] vga: fix banked access bounds checking (CVE-2016-3710)
+
+vga allows banked access to video memory using the window at 0xa00000
+and it supports a different access modes with different address
+calculations.
+
+The VBE bochs extentions support banked access too, using the
+VBE_DISPI_INDEX_BANK register.  The code tries to take the different
+address calculations into account and applies different limits to
+VBE_DISPI_INDEX_BANK depending on the current access mode.
+
+Which is probably effective in stopping misprogramming by accident.
+But from a security point of view completely useless as an attacker
+can easily change access modes after setting the bank register.
+
+Drop the bogus check, add range checks to vga_mem_{readb,writeb}
+instead.
+
+Fixes: CVE-2016-3710
+Reported-by: Qinghao Tang <luodalongde@gmail.com>
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
+---
+ hw/display/vga.c | 24 ++++++++++++++++++------
+ 1 file changed, 18 insertions(+), 6 deletions(-)
+
+diff --git a/hw/display/vga.c b/hw/display/vga.c
+index 52eaf05..b577712 100644
+--- a/hw/display/vga.c
++++ b/hw/display/vga.c
+@@ -178,6 +178,7 @@ static void vga_update_memory_access(VGACommonState *s)
+             break;
+         }
+         base += isa_mem_base;
++        assert(offset + size <= s->vram_size);
+         memory_region_init_alias(&s->chain4_alias, memory_region_owner(&s->vram),
+                                  "vga.chain4", &s->vram, offset, size);
+         memory_region_add_subregion_overlap(s->legacy_address_space, base,
+@@ -715,11 +716,7 @@ void vbe_ioport_write_data(void *opaque, uint32_t addr, uint32_t val)
+             vbe_fixup_regs(s);
+             break;
+         case VBE_DISPI_INDEX_BANK:
+-            if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4) {
+-              val &= (s->vbe_bank_mask >> 2);
+-            } else {
+-              val &= s->vbe_bank_mask;
+-            }
++            val &= s->vbe_bank_mask;
+             s->vbe_regs[s->vbe_index] = val;
+             s->bank_offset = (val << 16);
+             vga_update_memory_access(s);
+@@ -818,13 +815,21 @@ uint32_t vga_mem_readb(VGACommonState *s, hwaddr addr)
+ 
+     if (s->sr[VGA_SEQ_MEMORY_MODE] & VGA_SR04_CHN_4M) {
+         /* chain 4 mode : simplest access */
++        assert(addr < s->vram_size);
+         ret = s->vram_ptr[addr];
+     } else if (s->gr[VGA_GFX_MODE] & 0x10) {
+         /* odd/even mode (aka text mode mapping) */
+         plane = (s->gr[VGA_GFX_PLANE_READ] & 2) | (addr & 1);
+-        ret = s->vram_ptr[((addr & ~1) << 1) | plane];
++        addr = ((addr & ~1) << 1) | plane;
++        if (addr >= s->vram_size) {
++            return 0xff;
++        }
++        ret = s->vram_ptr[addr];
+     } else {
+         /* standard VGA latched access */
++        if (addr * sizeof(uint32_t) >= s->vram_size) {
++            return 0xff;
++        }
+         s->latch = ((uint32_t *)s->vram_ptr)[addr];
+ 
+         if (!(s->gr[VGA_GFX_MODE] & 0x08)) {
+@@ -881,6 +886,7 @@ void vga_mem_writeb(VGACommonState *s, hwaddr addr, uint32_t val)
+         plane = addr & 3;
+         mask = (1 << plane);
+         if (s->sr[VGA_SEQ_PLANE_WRITE] & mask) {
++            assert(addr < s->vram_size);
+             s->vram_ptr[addr] = val;
+ #ifdef DEBUG_VGA_MEM
+             printf("vga: chain4: [0x" TARGET_FMT_plx "]\n", addr);
+@@ -894,6 +900,9 @@ void vga_mem_writeb(VGACommonState *s, hwaddr addr, uint32_t val)
+         mask = (1 << plane);
+         if (s->sr[VGA_SEQ_PLANE_WRITE] & mask) {
+             addr = ((addr & ~1) << 1) | plane;
++            if (addr >= s->vram_size) {
++                return;
++            }
+             s->vram_ptr[addr] = val;
+ #ifdef DEBUG_VGA_MEM
+             printf("vga: odd/even: [0x" TARGET_FMT_plx "]\n", addr);
+@@ -967,6 +976,9 @@ void vga_mem_writeb(VGACommonState *s, hwaddr addr, uint32_t val)
+         mask = s->sr[VGA_SEQ_PLANE_WRITE];
+         s->plane_updated |= mask; /* only used to detect font change */
+         write_mask = mask16[mask];
++        if (addr * sizeof(uint32_t) >= s->vram_size) {
++            return;
++        }
+         ((uint32_t *)s->vram_ptr)[addr] =
+             (((uint32_t *)s->vram_ptr)[addr] & ~write_mask) |
+             (val & write_mask);
+-- 
+1.9.1
+
diff --git a/system/xen/patches/xsa179-qemuu-4.6-0002-vga-add-vbe_enabled-helper.patch b/system/xen/patches/xsa179-qemuu-4.6-0002-vga-add-vbe_enabled-helper.patch
new file mode 100644
index 000000000000..0daa3141ebab
--- /dev/null
+++ b/system/xen/patches/xsa179-qemuu-4.6-0002-vga-add-vbe_enabled-helper.patch
@@ -0,0 +1,68 @@
+From e026859e9aecf8635daf06e9fc2325239f458959 Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Tue, 26 Apr 2016 14:11:34 +0200
+Subject: [PATCH 2/5] vga: add vbe_enabled() helper
+
+Makes code a bit easier to read.
+
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
+---
+ hw/display/vga.c | 13 +++++++++----
+ 1 file changed, 9 insertions(+), 4 deletions(-)
+
+diff --git a/hw/display/vga.c b/hw/display/vga.c
+index b577712..ebf63ff 100644
+--- a/hw/display/vga.c
++++ b/hw/display/vga.c
+@@ -140,6 +140,11 @@ static uint32_t expand4[256];
+ static uint16_t expand2[256];
+ static uint8_t expand4to8[16];
+ 
++static inline bool vbe_enabled(VGACommonState *s)
++{
++    return s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED;
++}
++
+ static void vga_update_memory_access(VGACommonState *s)
+ {
+     hwaddr base, offset, size;
+@@ -563,7 +568,7 @@ static void vbe_fixup_regs(VGACommonState *s)
+     uint16_t *r = s->vbe_regs;
+     uint32_t bits, linelength, maxy, offset;
+ 
+-    if (!(r[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED)) {
++    if (!vbe_enabled(s)) {
+         /* vbe is turned off -- nothing to do */
+         return;
+     }
+@@ -1057,7 +1062,7 @@ static void vga_get_offsets(VGACommonState *s,
+ {
+     uint32_t start_addr, line_offset, line_compare;
+ 
+-    if (s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED) {
++    if (vbe_enabled(s)) {
+         line_offset = s->vbe_line_offset;
+         start_addr = s->vbe_start_addr;
+         line_compare = 65535;
+@@ -1382,7 +1387,7 @@ static int vga_get_bpp(VGACommonState *s)
+ {
+     int ret;
+ 
+-    if (s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED) {
++    if (vbe_enabled(s)) {
+         ret = s->vbe_regs[VBE_DISPI_INDEX_BPP];
+     } else {
+         ret = 0;
+@@ -1394,7 +1399,7 @@ static void vga_get_resolution(VGACommonState *s, int *pwidth, int *pheight)
+ {
+     int width, height;
+ 
+-    if (s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED) {
++    if (vbe_enabled(s)) {
+         width = s->vbe_regs[VBE_DISPI_INDEX_XRES];
+         height = s->vbe_regs[VBE_DISPI_INDEX_YRES];
+     } else {
+-- 
+1.9.1
+
diff --git a/system/xen/patches/xsa179-qemuu-4.6-0003-vga-factor-out-vga-register-setup.patch b/system/xen/patches/xsa179-qemuu-4.6-0003-vga-factor-out-vga-register-setup.patch
new file mode 100644
index 000000000000..70e4bdbca8d9
--- /dev/null
+++ b/system/xen/patches/xsa179-qemuu-4.6-0003-vga-factor-out-vga-register-setup.patch
@@ -0,0 +1,127 @@
+From b36a4e26caf7a050a6e8593527c26bfa4f47a758 Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Tue, 26 Apr 2016 15:24:18 +0200
+Subject: [PATCH 3/5] vga: factor out vga register setup
+
+When enabling vbe mode qemu will setup a bunch of vga registers to make
+sure the vga emulation operates in correct mode for a linear
+framebuffer.  Move that code to a separate function so we can call it
+from other places too.
+
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
+---
+ hw/display/vga.c | 78 ++++++++++++++++++++++++++++++++------------------------
+ 1 file changed, 44 insertions(+), 34 deletions(-)
+
+diff --git a/hw/display/vga.c b/hw/display/vga.c
+index ebf63ff..fb822f4 100644
+--- a/hw/display/vga.c
++++ b/hw/display/vga.c
+@@ -643,6 +643,49 @@ static void vbe_fixup_regs(VGACommonState *s)
+     s->vbe_start_addr  = offset / 4;
+ }
+ 
++/* we initialize the VGA graphic mode */
++static void vbe_update_vgaregs(VGACommonState *s)
++{
++    int h, shift_control;
++
++    if (!vbe_enabled(s)) {
++        /* vbe is turned off -- nothing to do */
++        return;
++    }
++
++    /* graphic mode + memory map 1 */
++    s->gr[VGA_GFX_MISC] = (s->gr[VGA_GFX_MISC] & ~0x0c) | 0x04 |
++        VGA_GR06_GRAPHICS_MODE;
++    s->cr[VGA_CRTC_MODE] |= 3; /* no CGA modes */
++    s->cr[VGA_CRTC_OFFSET] = s->vbe_line_offset >> 3;
++    /* width */
++    s->cr[VGA_CRTC_H_DISP] =
++        (s->vbe_regs[VBE_DISPI_INDEX_XRES] >> 3) - 1;
++    /* height (only meaningful if < 1024) */
++    h = s->vbe_regs[VBE_DISPI_INDEX_YRES] - 1;
++    s->cr[VGA_CRTC_V_DISP_END] = h;
++    s->cr[VGA_CRTC_OVERFLOW] = (s->cr[VGA_CRTC_OVERFLOW] & ~0x42) |
++        ((h >> 7) & 0x02) | ((h >> 3) & 0x40);
++    /* line compare to 1023 */
++    s->cr[VGA_CRTC_LINE_COMPARE] = 0xff;
++    s->cr[VGA_CRTC_OVERFLOW] |= 0x10;
++    s->cr[VGA_CRTC_MAX_SCAN] |= 0x40;
++
++    if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4) {
++        shift_control = 0;
++        s->sr[VGA_SEQ_CLOCK_MODE] &= ~8; /* no double line */
++    } else {
++        shift_control = 2;
++        /* set chain 4 mode */
++        s->sr[VGA_SEQ_MEMORY_MODE] |= VGA_SR04_CHN_4M;
++        /* activate all planes */
++        s->sr[VGA_SEQ_PLANE_WRITE] |= VGA_SR02_ALL_PLANES;
++    }
++    s->gr[VGA_GFX_MODE] = (s->gr[VGA_GFX_MODE] & ~0x60) |
++        (shift_control << 5);
++    s->cr[VGA_CRTC_MAX_SCAN] &= ~0x9f; /* no double scan */
++}
++
+ static uint32_t vbe_ioport_read_index(void *opaque, uint32_t addr)
+ {
+     VGACommonState *s = opaque;
+@@ -729,52 +772,19 @@ void vbe_ioport_write_data(void *opaque, uint32_t addr, uint32_t val)
+         case VBE_DISPI_INDEX_ENABLE:
+             if ((val & VBE_DISPI_ENABLED) &&
+                 !(s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED)) {
+-                int h, shift_control;
+ 
+                 s->vbe_regs[VBE_DISPI_INDEX_VIRT_WIDTH] = 0;
+                 s->vbe_regs[VBE_DISPI_INDEX_X_OFFSET] = 0;
+                 s->vbe_regs[VBE_DISPI_INDEX_Y_OFFSET] = 0;
+                 s->vbe_regs[VBE_DISPI_INDEX_ENABLE] |= VBE_DISPI_ENABLED;
+                 vbe_fixup_regs(s);
++                vbe_update_vgaregs(s);
+ 
+                 /* clear the screen */
+                 if (!(val & VBE_DISPI_NOCLEARMEM)) {
+                     memset(s->vram_ptr, 0,
+                            s->vbe_regs[VBE_DISPI_INDEX_YRES] * s->vbe_line_offset);
+                 }
+-
+-                /* we initialize the VGA graphic mode */
+-                /* graphic mode + memory map 1 */
+-                s->gr[VGA_GFX_MISC] = (s->gr[VGA_GFX_MISC] & ~0x0c) | 0x04 |
+-                    VGA_GR06_GRAPHICS_MODE;
+-                s->cr[VGA_CRTC_MODE] |= 3; /* no CGA modes */
+-                s->cr[VGA_CRTC_OFFSET] = s->vbe_line_offset >> 3;
+-                /* width */
+-                s->cr[VGA_CRTC_H_DISP] =
+-                    (s->vbe_regs[VBE_DISPI_INDEX_XRES] >> 3) - 1;
+-                /* height (only meaningful if < 1024) */
+-                h = s->vbe_regs[VBE_DISPI_INDEX_YRES] - 1;
+-                s->cr[VGA_CRTC_V_DISP_END] = h;
+-                s->cr[VGA_CRTC_OVERFLOW] = (s->cr[VGA_CRTC_OVERFLOW] & ~0x42) |
+-                    ((h >> 7) & 0x02) | ((h >> 3) & 0x40);
+-                /* line compare to 1023 */
+-                s->cr[VGA_CRTC_LINE_COMPARE] = 0xff;
+-                s->cr[VGA_CRTC_OVERFLOW] |= 0x10;
+-                s->cr[VGA_CRTC_MAX_SCAN] |= 0x40;
+-
+-                if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4) {
+-                    shift_control = 0;
+-                    s->sr[VGA_SEQ_CLOCK_MODE] &= ~8; /* no double line */
+-                } else {
+-                    shift_control = 2;
+-                    /* set chain 4 mode */
+-                    s->sr[VGA_SEQ_MEMORY_MODE] |= VGA_SR04_CHN_4M;
+-                    /* activate all planes */
+-                    s->sr[VGA_SEQ_PLANE_WRITE] |= VGA_SR02_ALL_PLANES;
+-                }
+-                s->gr[VGA_GFX_MODE] = (s->gr[VGA_GFX_MODE] & ~0x60) |
+-                    (shift_control << 5);
+-                s->cr[VGA_CRTC_MAX_SCAN] &= ~0x9f; /* no double scan */
+             } else {
+                 s->bank_offset = 0;
+             }
+-- 
+1.9.1
+
diff --git a/system/xen/patches/xsa179-qemuu-4.6-0004-vga-update-vga-register-setup-on-vbe-changes.patch b/system/xen/patches/xsa179-qemuu-4.6-0004-vga-update-vga-register-setup-on-vbe-changes.patch
new file mode 100644
index 000000000000..0638edb91be8
--- /dev/null
+++ b/system/xen/patches/xsa179-qemuu-4.6-0004-vga-update-vga-register-setup-on-vbe-changes.patch
@@ -0,0 +1,29 @@
+From ef8bd1b26a597ae7c306227655626640093cb7a2 Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Tue, 26 Apr 2016 15:39:22 +0200
+Subject: [PATCH 4/5] vga: update vga register setup on vbe changes
+
+Call the new vbe_update_vgaregs() function on vbe configuration
+changes, to make sure vga registers are up-to-date.
+
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
+---
+ hw/display/vga.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/hw/display/vga.c b/hw/display/vga.c
+index fb822f4..3739758 100644
+--- a/hw/display/vga.c
++++ b/hw/display/vga.c
+@@ -762,6 +762,7 @@ void vbe_ioport_write_data(void *opaque, uint32_t addr, uint32_t val)
+         case VBE_DISPI_INDEX_Y_OFFSET:
+             s->vbe_regs[s->vbe_index] = val;
+             vbe_fixup_regs(s);
++            vbe_update_vgaregs(s);
+             break;
+         case VBE_DISPI_INDEX_BANK:
+             val &= s->vbe_bank_mask;
+-- 
+1.9.1
+
diff --git a/system/xen/patches/xsa179-qemuu-4.6-0005-vga-make-sure-vga-register-setup-for-vbe-stays-intac.patch b/system/xen/patches/xsa179-qemuu-4.6-0005-vga-make-sure-vga-register-setup-for-vbe-stays-intac.patch
new file mode 100644
index 000000000000..c22f2d719519
--- /dev/null
+++ b/system/xen/patches/xsa179-qemuu-4.6-0005-vga-make-sure-vga-register-setup-for-vbe-stays-intac.patch
@@ -0,0 +1,75 @@
+From 92456c0c361d5da858d544647c6246ec78ed922b Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Tue, 26 Apr 2016 14:48:06 +0200
+Subject: [PATCH 5/5] vga: make sure vga register setup for vbe stays intact
+ (CVE-2016-3712).
+
+Call vbe_update_vgaregs() when the guest touches GFX, SEQ or CRT
+registers, to make sure the vga registers will always have the
+values needed by vbe mode.  This makes sure the sanity checks
+applied by vbe_fixup_regs() are effective.
+
+Without this guests can muck with shift_control, can turn on planar
+vga modes or text mode emulation while VBE is active, making qemu
+take code paths meant for CGA compatibility, but with the very
+large display widths and heigts settable using VBE registers.
+
+Which is good for one or another buffer overflow.  Not that
+critical as they typically read overflows happening somewhere
+in the display code.  So guests can DoS by crashing qemu with a
+segfault, but it is probably not possible to break out of the VM.
+
+Fixes: CVE-2016-3712
+Reported-by: Zuozhi Fzz <zuozhi.fzz@alibaba-inc.com>
+Reported-by: P J P <ppandit@redhat.com>
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
+---
+ hw/display/vga.c | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+diff --git a/hw/display/vga.c b/hw/display/vga.c
+index 3739758..e7be97e 100644
+--- a/hw/display/vga.c
++++ b/hw/display/vga.c
+@@ -140,6 +140,8 @@ static uint32_t expand4[256];
+ static uint16_t expand2[256];
+ static uint8_t expand4to8[16];
+ 
++static void vbe_update_vgaregs(VGACommonState *s);
++
+ static inline bool vbe_enabled(VGACommonState *s)
+ {
+     return s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED;
+@@ -483,6 +485,7 @@ void vga_ioport_write(void *opaque, uint32_t addr, uint32_t val)
+         printf("vga: write SR%x = 0x%02x\n", s->sr_index, val);
+ #endif
+         s->sr[s->sr_index] = val & sr_mask[s->sr_index];
++        vbe_update_vgaregs(s);
+         if (s->sr_index == VGA_SEQ_CLOCK_MODE) {
+             s->update_retrace_info(s);
+         }
+@@ -514,6 +517,7 @@ void vga_ioport_write(void *opaque, uint32_t addr, uint32_t val)
+         printf("vga: write GR%x = 0x%02x\n", s->gr_index, val);
+ #endif
+         s->gr[s->gr_index] = val & gr_mask[s->gr_index];
++        vbe_update_vgaregs(s);
+         vga_update_memory_access(s);
+         break;
+     case VGA_CRT_IM:
+@@ -532,10 +536,12 @@ void vga_ioport_write(void *opaque, uint32_t addr, uint32_t val)
+             if (s->cr_index == VGA_CRTC_OVERFLOW) {
+                 s->cr[VGA_CRTC_OVERFLOW] = (s->cr[VGA_CRTC_OVERFLOW] & ~0x10) |
+                     (val & 0x10);
++                vbe_update_vgaregs(s);
+             }
+             return;
+         }
+         s->cr[s->cr_index] = val;
++        vbe_update_vgaregs(s);
+ 
+         switch(s->cr_index) {
+         case VGA_CRTC_H_TOTAL:
+-- 
+1.9.1
+
diff --git a/system/xen/patches/xsa181.patch b/system/xen/patches/xsa181.patch
new file mode 100644
index 000000000000..c44541ec4d93
--- /dev/null
+++ b/system/xen/patches/xsa181.patch
@@ -0,0 +1,38 @@
+From ee488e2133e581967d13d5287d7bd654e9b2e2a6 Mon Sep 17 00:00:00 2001
+From: Andrew Cooper <andrew.cooper3@citrix.com>
+Date: Thu, 2 Jun 2016 14:19:00 +0100
+Subject: [PATCH] xen/arm: Don't free p2m->root in p2m_teardown() before it has
+ been allocated
+
+If p2m_init() didn't complete successfully, (e.g. due to VMID
+exhaustion), p2m_teardown() is called and unconditionally tries to free
+p2m->root before it has been allocated.  free_domheap_pages() doesn't
+tolerate NULL pointers.
+
+This is XSA-181
+
+Reported-by: Aaron Cornelius <Aaron.Cornelius@dornerworks.com>
+Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Reviewed-by: Julien Grall <julien.grall@arm.com>
+---
+ xen/arch/arm/p2m.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
+index 838d004..6a19c57 100644
+--- a/xen/arch/arm/p2m.c
++++ b/xen/arch/arm/p2m.c
+@@ -1408,7 +1408,8 @@ void p2m_teardown(struct domain *d)
+     while ( (pg = page_list_remove_head(&p2m->pages)) )
+         free_domheap_page(pg);
+ 
+-    free_domheap_pages(p2m->root, P2M_ROOT_ORDER);
++    if ( p2m->root )
++        free_domheap_pages(p2m->root, P2M_ROOT_ORDER);
+ 
+     p2m->root = NULL;
+ 
+-- 
+2.1.4
+