#!/bin/sh test "$1" = "-h" && { echo afl-system-config by Marc Heuse echo echo $0 echo echo afl-system-config has no command line options echo echo afl-system reconfigures the system to a high performance fuzzing state echo WARNING: this reduces the security of the system echo exit 1 } PLATFORM=`uname -s` echo This reconfigures the system to have a better fuzzing performance if [ '!' "$EUID" = 0 ] && [ '!' `id -u` = 0 ] ; then echo Error you need to be root to run this exit 1 fi if [ "$PLATFORM" = "Linux" ] ; then sysctl -w kernel.core_pattern=core sysctl -w kernel.randomize_va_space=0 sysctl -w kernel.sched_child_runs_first=1 sysctl -w kernel.sched_autogroup_enabled=1 sysctl -w kernel.sched_migration_cost_ns=50000000 sysctl -w kernel.sched_latency_ns=250000000 echo never > /sys/kernel/mm/transparent_hugepage/enabled test -e /sys/devices/system/cpu/cpufreq/scaling_governor && echo performance | tee /sys/devices/system/cpu/cpufreq/scaling_governor test -e /sys/devices/system/cpu/cpufreq/policy0/scaling_governor && echo performance | tee /sys/devices/system/cpu/cpufreq/policy*/scaling_governor test -e /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor && echo performance | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor test -e /sys/devices/system/cpu/intel_pstate/no_turbo && echo 0 > /sys/devices/system/cpu/intel_pstate/no_turbo test -e /sys/devices/system/cpu/cpufreq/boost && echo 1 > /sys/devices/system/cpu/cpufreq/boost echo echo It is recommended to boot the kernel with lots of security off - if you are running a machine that is in a secured network - so set this: echo '/etc/default/grub:GRUB_CMDLINE_LINUX_DEFAULT="ibpb=off ibrs=off kpti=off l1tf=off mds=off mitigations=off no_stf_barrier noibpb noibrs nopcid nopti nospec_store_bypass_disable nospectre_v1 nospectre_v2 pcid=off pti=off spec_store_bypass_disable=off spectre_v2=off stf_barrier=off"' fi if [ "$PLATFORM" = "FreeBSD" ] ; then sysctl kern.elf32.aslr.enable=0 sysctl kern.elf64.aslr.enable=0 echo echo It is recommended to boot the kernel with lots of security off - if you are running a machine that is in a secured network - so set this: echo 'sysctl hw.ibrs_disable=1' echo echo 'Setting kern.pmap.pg_ps_enabled=0 into /boot/loader.conf might be helpful too.' fi if [ "$PLATFORM" = "OpenBSD" ] ; then echo echo 'System security features cannot be disabled on OpenBSD.' fi if [ "$PLATFORM" = "NetBSD" ] ; then echo echo It is recommended to enable unprivileged users to set cpu affinity echo to be able to use afl-gotcpu meaningfully. /sbin/sysctl -w security.models.extensions.user_set_cpu_affinity=1 fi if [ "$PLATFORM" = "Darwin" ] ; then if [ $(launchctl list 2>/dev/null | grep -q '\.ReportCrash$') ] ; then echo We unload the default crash reporter here SL=/System/Library; PL=com.apple.ReportCrash launchctl unload -w ${SL}/LaunchAgents/${PL}.plist sudo launchctl unload -w ${SL}/LaunchDaemons/${PL}.Root.plist fi fi echo echo Also use AFL_TMPDIR to use a tmpfs for the input file