[IA64] vmx_vcpu_set_rr: check rid validity

Signed-off-by: Tristan Gingold <tristan.gingold@bull.net>

xen/arch/ia64/vmx/vmx_vcpu.c

@@ -210,8 +210,11 @@ IA64FAULT vmx_vcpu_set_rr(VCPU *vcpu, UINT64 reg, UINT64 val)
     ia64_rr oldrr,newrr;
     thash_cb_t *hcb;
     extern void * pal_vaddr;
+
     vcpu_get_rr(vcpu, reg, &oldrr.rrval);
     newrr.rrval=val;
+    if (newrr.rid >= (1 << vcpu->domain->arch.rid_bits))
+        panic_domain (NULL, "use of invalid rid %lx\n", newrr.rid);
     if(oldrr.ps!=newrr.ps){
         hcb = vmx_vcpu_get_vtlb(vcpu);
         thash_purge_all(hcb);