[Xen-changelog] [xen master] x86/mm: fix checks against max_mapped_pfn

[patchbot@xxxxxxx]

commit 088ee1d47b65d6bb92de61b404805f4ca92e3240
Author:     Jan Beulich <JBeulich@xxxxxxxx>
AuthorDate: Thu Apr 3 08:47:28 2014 +0100
Commit:     Tim Deegan <tim@xxxxxxx>
CommitDate: Thu Apr 3 12:08:43 2014 +0100

    x86/mm: fix checks against max_mapped_pfn
    
    This value is an inclusive one, i.e. this fixes an off-by-one in memory
    sharing and an off-by-two in shadow code.
    
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Tim Deegan <tim@xxxxxxx>
---
 xen/arch/x86/mm/mem_sharing.c   |    4 ++--
 xen/arch/x86/mm/shadow/common.c |    4 +---
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/xen/arch/x86/mm/mem_sharing.c b/xen/arch/x86/mm/mem_sharing.c
index 7ed6594..237d346 100644
--- a/xen/arch/x86/mm/mem_sharing.c
+++ b/xen/arch/x86/mm/mem_sharing.c
@@ -1267,8 +1267,8 @@ int relinquish_shared_pages(struct domain *d)
         return 0;
 
     p2m_lock(p2m);
-    for (gfn = p2m->next_shared_gfn_to_relinquish; 
-         gfn < p2m->max_mapped_pfn; gfn++ )
+    for ( gfn = p2m->next_shared_gfn_to_relinquish;
+          gfn <= p2m->max_mapped_pfn; gfn++ )
     {
         p2m_access_t a;
         p2m_type_t t;
diff --git a/xen/arch/x86/mm/shadow/common.c b/xen/arch/x86/mm/shadow/common.c
index 517b5f1..9258d2a 100644
--- a/xen/arch/x86/mm/shadow/common.c
+++ b/xen/arch/x86/mm/shadow/common.c
@@ -3487,9 +3487,7 @@ int shadow_track_dirty_vram(struct domain *d,
     struct sh_dirty_vram *dirty_vram = d->arch.hvm_domain.dirty_vram;
     struct p2m_domain *p2m = p2m_get_hostp2m(d);
 
-    if (end_pfn < begin_pfn
-            || begin_pfn > p2m->max_mapped_pfn
-            || end_pfn >= p2m->max_mapped_pfn)
+    if ( end_pfn < begin_pfn || end_pfn > p2m->max_mapped_pfn + 1 )
         return -EINVAL;
 
     /* We perform p2m lookups, so lock the p2m upfront to avoid deadlock */
--
generated by git-patchbot for /home/xen/git/xen.git#master

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