Integer overflow

Multiple integer overflows in the 1 FLASKGETBOOL, 2 FLASKSETBOOL, 3 FLASKUSER, and 4 FLASKCONTEXTTOSID suboperations in the flask hypercall in Xen 4.3.x, 4.2.x, 4.1.x, 3.2.x, and earlier, when XSM is enabled, allow local users to cause a denial of service processor fault via unspecified vectors, ...