The __get_user_asm_ex macro in arch/x86/include/asm/uaccess.h in the Linux kernel before 4.7.5 does not initialize a certain integer variable, which allows local users to obtain sensitive information from kernel stack memory by triggering failure of a get_user_ex call. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-9178
