# Protect the zero page of memory from userspace mmap to prevent kernel # NULL-dereference attacks against potential future kernel security # vulnerabilities. (Added in kernel 2.6.23.) # # While this default is built into the Ubuntu kernel, there is no way to # restore the kernel default if the value is changed during runtime; for # example via package removal (e.g. wine, dosemu). Therefore, this value # is reset to the secure default each time the sysctl values are loaded. vm.mmap_min_addr = 65536