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pkgsrc-ng/sysutils/xenkernel41/patches/patch-CVE-2013-1918_8
2013-09-26 17:14:40 +02:00

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$NetBSD: patch-CVE-2013-1918_8,v 1.1 2013/05/03 16:48:38 drochner Exp $
--- xen/arch/x86/x86_64/compat/mm.c.orig 2013-05-03 13:37:44.000000000 +0000
+++ xen/arch/x86/x86_64/compat/mm.c
@@ -222,6 +222,13 @@ int compat_mmuext_op(XEN_GUEST_HANDLE(mm
int rc = 0;
XEN_GUEST_HANDLE(mmuext_op_t) nat_ops;
+ if ( unlikely(count == MMU_UPDATE_PREEMPTED) &&
+ likely(guest_handle_is_null(cmp_uops)) )
+ {
+ set_xen_guest_handle(nat_ops, NULL);
+ return do_mmuext_op(nat_ops, count, pdone, foreigndom);
+ }
+
preempt_mask = count & MMU_UPDATE_PREEMPTED;
count ^= preempt_mask;
@@ -319,17 +326,23 @@ int compat_mmuext_op(XEN_GUEST_HANDLE(mm
: mcs->call.args[1];
unsigned int left = arg1 & ~MMU_UPDATE_PREEMPTED;
- BUG_ON(left == arg1);
+ BUG_ON(left == arg1 && left != i);
BUG_ON(left > count);
guest_handle_add_offset(nat_ops, i - left);
guest_handle_subtract_offset(cmp_uops, left);
left = 1;
- BUG_ON(!hypercall_xlat_continuation(&left, 0x01, nat_ops, cmp_uops));
- BUG_ON(left != arg1);
- if (!test_bit(_MCSF_in_multicall, &mcs->flags))
- regs->_ecx += count - i;
+ if ( arg1 != MMU_UPDATE_PREEMPTED )
+ {
+ BUG_ON(!hypercall_xlat_continuation(&left, 0x01, nat_ops,
+ cmp_uops));
+ if ( !test_bit(_MCSF_in_multicall, &mcs->flags) )
+ regs->_ecx += count - i;
+ else
+ mcs->compat_call.args[1] += count - i;
+ }
else
- mcs->compat_call.args[1] += count - i;
+ BUG_ON(hypercall_xlat_continuation(&left, 0));
+ BUG_ON(left != arg1);
}
else
BUG_ON(err > 0);