diff options
Diffstat (limited to 'xsa345-2.patch')
| -rw-r--r-- | xsa345-2.patch | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/xsa345-2.patch b/xsa345-2.patch new file mode 100644 index 0000000..a007f05 --- /dev/null +++ b/xsa345-2.patch @@ -0,0 +1,55 @@ +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. + +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> + +--- a/xen/arch/x86/mm.c ++++ b/xen/arch/x86/mm.c +@@ -5564,6 +5564,7 @@ int modify_xen_mappings(unsigned long s, + 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) +@@ -5605,7 +5606,8 @@ int modify_xen_mappings(unsigned long s, + /* 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) + +@@ -5660,7 +5662,8 @@ int modify_xen_mappings(unsigned long s, + /* 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, +@@ -5789,7 +5792,10 @@ int modify_xen_mappings(unsigned long s, + flush_area(NULL, FLUSH_TLB_GLOBAL); + + #undef FLAGS_MASK +- return 0; ++ rc = 0; ++ ++ out: ++ return rc; + } + + #undef flush_area |