1 files changed, 68 insertions, 0 deletions
diff --git a/system/xen/xsa/xsa345-0002-x86-mm-Refactor-modify_xen_mappings-to-have-one-exit.patch b/system/xen/xsa/xsa345-0002-x86-mm-Refactor-modify_xen_mappings-to-have-one-exit.patch
new file mode 100644
index 0000000000..836bed681a
--- /dev/null
+++ b/system/xen/xsa/xsa345-0002-x86-mm-Refactor-modify_xen_mappings-to-have-one-exit.patch
@@ -0,0 +1,68 @@
+From 9f6f35b833d295acaaa2d8ff8cf309bf688cfd50 Mon Sep 17 00:00:00 2001
+From: Wei Liu <wei.liu2@citrix.com>
+Date: Sat, 11 Jan 2020 21:57:42 +0000
+Subject: [PATCH 2/3] x86/mm: Refactor modify_xen_mappings to have one exit
+ path
+
+We will soon need to perform clean-ups before returning.
+
+No functional change.
+
+This is part of XSA-345.
+
+Reported-by: Hongyan Xia <hongyxia@amazon.com>
+Signed-off-by: Wei Liu <wei.liu2@citrix.com>
+Signed-off-by: Hongyan Xia <hongyxia@amazon.com>
+Signed-off-by: George Dunlap <george.dunlap@citrix.com>
+Acked-by: Jan Beulich <jbeulich@suse.com>
+---
+ xen/arch/x86/mm.c | 12 +++++++++---
+ 1 file changed, 9 insertions(+), 3 deletions(-)
+
+diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
+index 133a393875..af726d3274 100644
+--- a/xen/arch/x86/mm.c
++++ b/xen/arch/x86/mm.c
+@@ -5570,6 +5570,7 @@ int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf)
+     l1_pgentry_t *pl1e;
+     unsigned int  i;
+     unsigned long v = s;
++    int rc = -ENOMEM;
+ 
+     /* Set of valid PTE bits which may be altered. */
+ #define FLAGS_MASK (_PAGE_NX|_PAGE_RW|_PAGE_PRESENT)
+@@ -5611,7 +5612,8 @@ int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf)
+             /* PAGE1GB: shatter the superpage and fall through. */
+             pl2e = alloc_xen_pagetable();
+             if ( !pl2e )
+-                return -ENOMEM;
++                goto out;
++
+             for ( i = 0; i < L2_PAGETABLE_ENTRIES; i++ )
+                 l2e_write(pl2e + i,
+                           l2e_from_pfn(l3e_get_pfn(*pl3e) +
+@@ -5666,7 +5668,8 @@ int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf)
+                 /* PSE: shatter the superpage and try again. */
+                 pl1e = alloc_xen_pagetable();
+                 if ( !pl1e )
+-                    return -ENOMEM;
++                    goto out;
++
+                 for ( i = 0; i < L1_PAGETABLE_ENTRIES; i++ )
+                     l1e_write(&pl1e[i],
+                               l1e_from_pfn(l2e_get_pfn(*pl2e) + i,
+@@ -5795,7 +5798,10 @@ int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf)
+     flush_area(NULL, FLUSH_TLB_GLOBAL);
+ 
+ #undef FLAGS_MASK
+-    return 0;
++    rc = 0;
++
++ out:
++    return rc;
+ }
+ 
+ #undef flush_area
+-- 
+2.25.1
+