system/xen: Additional features, patches and script fixes.

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

4 files changed, 263 insertions, 0 deletions

diff --git a/system/xen/xsa/xsa182-4.6.patch b/system/xen/xsa/xsa182-4.6.patch
new file mode 100644
index 0000000000..be2047d688
--- /dev/null
+++ b/system/xen/xsa/xsa182-4.6.patch
@@ -0,0 +1,102 @@
+From f48a75b0c10ac79b287ca2b580ecb9ea2f696607 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
+
+Reported-by: Jérémie Boutoille <jboutoille@ext.quarkslab.com>
+Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Reviewed-by: Tim Deegan <tim@xen.org>
+---
+ xen/arch/x86/mm.c          | 28 ++++++++++++++++------------
+ xen/include/asm-x86/page.h |  1 +
+ 2 files changed, 17 insertions(+), 12 deletions(-)
+
+diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
+index daf02ab..8dd22b8 100644
+--- a/xen/arch/x86/mm.c
++++ b/xen/arch/x86/mm.c
+@@ -1780,6 +1780,14 @@ static inline int update_intpte(intpte_t *p,
+                   _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,
+@@ -1820,9 +1828,8 @@ static int mod_l1_entry(l1_pgentry_t *pl1e, l1_pgentry_t nl1e,
+             return -EINVAL;
+         }
+ 
+-        /* Fast path for identical mapping, r/w, presence, and cachability. */
+-        if ( !l1e_has_changed(ol1e, nl1e,
+-                              PAGE_CACHE_ATTRS | _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,
+@@ -1904,11 +1911,8 @@ static int mod_l2_entry(l2_pgentry_t *pl2e,
+             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) )
+@@ -1973,8 +1977,8 @@ static int mod_l3_entry(l3_pgentry_t *pl3e,
+             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);
+@@ -2037,8 +2041,8 @@ static int mod_l4_entry(l4_pgentry_t *pl4e,
+             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);
+diff --git a/xen/include/asm-x86/page.h b/xen/include/asm-x86/page.h
+index 66b611c..1a59ed8 100644
+--- a/xen/include/asm-x86/page.h
++++ b/xen/include/asm-x86/page.h
+@@ -311,6 +311,7 @@ void efi_update_l4_pgtable(unsigned int l4idx, l4_pgentry_t);
+ #define _PAGE_AVAIL2   _AC(0x800,U)
+ #define _PAGE_AVAIL    _AC(0xE00,U)
+ #define _PAGE_PSE_PAT  _AC(0x1000,U)
++#define _PAGE_AVAIL_HIGH (_AC(0x7ff, U) << 12)
+ #define _PAGE_NX       (cpu_has_nx ? _PAGE_NX_BIT : 0)
+ /* non-architectural flags */
+ #define _PAGE_PAGED   0x2000U
+-- 
+2.1.4
+
diff --git a/system/xen/xsa/xsa183-4.6.patch b/system/xen/xsa/xsa183-4.6.patch
new file mode 100644
index 0000000000..84d70077c8
--- /dev/null
+++ b/system/xen/xsa/xsa183-4.6.patch
@@ -0,0 +1,75 @@
+From 777ebe30e81ab284f9b78392875fe884a593df35 Mon Sep 17 00:00:00 2001
+From: Andrew Cooper <andrew.cooper3@citrix.com>
+Date: Wed, 15 Jun 2016 18:32:14 +0100
+Subject: [PATCH] x86/entry: Avoid SMAP violation in
+ compat_create_bounce_frame()
+
+A 32bit guest kernel might be running on user mappings.
+compat_create_bounce_frame() must whitelist its guest accesses to avoid
+risking a SMAP violation.
+
+For both variants of create_bounce_frame(), re-blacklist user accesses if
+execution exits via an exception table redirection.
+
+This is XSA-183 / CVE-2016-6259
+
+Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Reviewed-by: George Dunlap <george.dunlap@citrix.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+---
+v2:
+ * Include CLAC on the exit paths from compat_create_bounce_frame which occur
+   from faults attempting to load %fs
+ * Reposition ASM_STAC to avoid breaking the macro-op fusion of test/jz
+---
+ xen/arch/x86/x86_64/compat/entry.S | 3 +++
+ xen/arch/x86/x86_64/entry.S        | 2 ++
+ 2 files changed, 5 insertions(+)
+
+diff --git a/xen/arch/x86/x86_64/compat/entry.S b/xen/arch/x86/x86_64/compat/entry.S
+index 0e3db7c..1eaf4bb 100644
+--- a/xen/arch/x86/x86_64/compat/entry.S
++++ b/xen/arch/x86/x86_64/compat/entry.S
+@@ -350,6 +350,7 @@ ENTRY(compat_int80_direct_trap)
+ compat_create_bounce_frame:
+         ASSERT_INTERRUPTS_ENABLED
+         mov   %fs,%edi
++        ASM_STAC
+         testb $2,UREGS_cs+8(%rsp)
+         jz    1f
+         /* Push new frame at registered guest-OS stack base. */
+@@ -403,6 +404,7 @@ UNLIKELY_START(nz, compat_bounce_failsafe)
+         movl  %ds,%eax
+ .Lft12: movl  %eax,%fs:0*4(%rsi)        # DS
+ UNLIKELY_END(compat_bounce_failsafe)
++        ASM_CLAC
+         /* Rewrite our stack frame and return to guest-OS mode. */
+         /* IA32 Ref. Vol. 3: TF, VM, RF and NT flags are cleared on trap. */
+         andl  $~(X86_EFLAGS_VM|X86_EFLAGS_RF|\
+@@ -448,6 +450,7 @@ compat_crash_page_fault_4:
+         addl  $4,%esi
+ compat_crash_page_fault:
+ .Lft14: mov   %edi,%fs
++        ASM_CLAC
+         movl  %esi,%edi
+         call  show_page_walk
+         jmp   dom_crash_sync_extable
+diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S
+index 6e27508..0c2e63a 100644
+--- a/xen/arch/x86/x86_64/entry.S
++++ b/xen/arch/x86/x86_64/entry.S
+@@ -462,9 +462,11 @@ domain_crash_page_fault_16:
+ domain_crash_page_fault_8:
+         addq  $8,%rsi
+ domain_crash_page_fault:
++        ASM_CLAC
+         movq  %rsi,%rdi
+         call  show_page_walk
+ ENTRY(dom_crash_sync_extable)
++        ASM_CLAC
+         # Get out of the guest-save area of the stack.
+         GET_STACK_BASE(%rax)
+         leaq  STACK_CPUINFO_FIELD(guest_cpu_user_regs)(%rax),%rsp
+-- 
+2.1.4
+
diff --git a/system/xen/xsa/xsa184-qemut-master.patch b/system/xen/xsa/xsa184-qemut-master.patch
new file mode 100644
index 0000000000..d15167f4ac
--- /dev/null
+++ b/system/xen/xsa/xsa184-qemut-master.patch
@@ -0,0 +1,43 @@
+From 17d8c4e47dfb41cb6778520ff2eab7a11fe12dfd Mon Sep 17 00:00:00 2001
+From: P J P <ppandit@redhat.com>
+Date: Tue, 26 Jul 2016 15:31:59 +0100
+Subject: [PATCH] virtio: error out if guest exceeds virtqueue size
+
+A broken or malicious guest can submit more requests than the virtqueue
+size permits.
+
+The guest can submit requests without bothering to wait for completion
+and is therefore not bound by virtqueue size.  This requires reusing
+vring descriptors in more than one request, which is incorrect but
+possible.  Processing a request allocates a VirtQueueElement and
+therefore causes unbounded memory allocation controlled by the guest.
+
+Exit with an error if the guest provides more requests than the
+virtqueue size permits.  This bounds memory allocation and makes the
+buggy guest visible to the user.
+
+Reported-by: Zhenhao Hong <zhenhaohong@gmail.com>
+Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
+---
+ hw/virtio.c | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/hw/virtio.c b/hw/virtio.c
+index c26feff..42897bf 100644
+--- a/hw/virtio.c
++++ b/hw/virtio.c
+@@ -421,6 +421,11 @@ int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem)
+     /* When we start there are none of either input nor output. */
+     elem->out_num = elem->in_num = 0;
+ 
++    if (vq->inuse >= vq->vring.num) {
++        fprintf(stderr, "Virtqueue size exceeded");
++        exit(1);
++    }
++
+     i = head = virtqueue_get_head(vq, vq->last_avail_idx++);
+     do {
+         struct iovec *sg;
+-- 
+2.1.4
+
diff --git a/system/xen/xsa/xsa184-qemuu-master.patch b/system/xen/xsa/xsa184-qemuu-master.patch
new file mode 100644
index 0000000000..ef96bff80c
--- /dev/null
+++ b/system/xen/xsa/xsa184-qemuu-master.patch
@@ -0,0 +1,43 @@
+From e469db25d6b2e5c71cd15451889226641c53a5cd Mon Sep 17 00:00:00 2001
+From: P J P <ppandit@redhat.com>
+Date: Mon, 25 Jul 2016 17:37:18 +0530
+Subject: [PATCH] virtio: error out if guest exceeds virtqueue size
+
+A broken or malicious guest can submit more requests than the virtqueue
+size permits.
+
+The guest can submit requests without bothering to wait for completion
+and is therefore not bound by virtqueue size.  This requires reusing
+vring descriptors in more than one request, which is incorrect but
+possible.  Processing a request allocates a VirtQueueElement and
+therefore causes unbounded memory allocation controlled by the guest.
+
+Exit with an error if the guest provides more requests than the
+virtqueue size permits.  This bounds memory allocation and makes the
+buggy guest visible to the user.
+
+Reported-by: Zhenhao Hong <zhenhaohong@gmail.com>
+Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
+---
+ hw/virtio/virtio.c | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
+index d24f775..f8ac0fb 100644
+--- a/hw/virtio/virtio.c
++++ b/hw/virtio/virtio.c
+@@ -483,6 +483,11 @@ int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem)
+ 
+     max = vq->vring.num;
+ 
++    if (vq->inuse >= max) {
++        error_report("Virtqueue size exceeded");
++        exit(1);
++    }
++
+     i = head = virtqueue_get_head(vq, vq->last_avail_idx++);
+     if (virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) {
+         vring_set_avail_event(vq, vq->last_avail_idx);
+-- 
+2.1.4
+