mirror of
https://github.com/speed47/spectre-meltdown-checker.git
synced 2024-10-03 22:18:02 +02:00
e05ec5c85f
Implement detection of mitigation for Variant 1 that is being pushed on vanilla kernel. Current name of the patch: "spectre variant1 mitigations for tip/x86/pti" (v6) Also detect some distros that already backported this patch without modifying the vulnerabilities sysfs hierarchy. This detection is more reliable than the LFENCE one, trust it and skip the LFENCE heuristic if a match is found.
1779 lines
60 KiB
Bash
Executable File
1779 lines
60 KiB
Bash
Executable File
#! /bin/sh
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# Spectre & Meltdown checker
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#
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# Check for the latest version at:
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# https://github.com/speed47/spectre-meltdown-checker
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# git clone https://github.com/speed47/spectre-meltdown-checker.git
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# or wget https://raw.githubusercontent.com/speed47/spectre-meltdown-checker/master/spectre-meltdown-checker.sh
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#
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# Stephane Lesimple
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#
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VERSION='0.33+'
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show_usage()
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{
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# shellcheck disable=SC2086
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cat <<EOF
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Usage:
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Live mode: $(basename $0) [options] [--live]
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Offline mode: $(basename $0) [options] [--kernel <vmlinux_file>] [--config <kernel_config>] [--map <kernel_map_file>]
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Modes:
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Two modes are available.
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First mode is the "live" mode (default), it does its best to find information about the currently running kernel.
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To run under this mode, just start the script without any option (you can also use --live explicitly)
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Second mode is the "offline" mode, where you can inspect a non-running kernel.
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You'll need to specify the location of the vmlinux file, config and System.map files:
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--kernel vmlinux_file Specify a (possibly compressed) vmlinux file
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--config kernel_config Specify a kernel config file
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--map kernel_map_file Specify a kernel System.map file
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Options:
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--no-color Don't use color codes
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--verbose, -v Increase verbosity level
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--no-sysfs Don't use the /sys interface even if present
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--sysfs-only Only use the /sys interface, don't run our own checks
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--coreos Special mode for CoreOS (use an ephemeral toolbox to inspect kernel)
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--batch text Produce machine readable output, this is the default if --batch is specified alone
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--batch json Produce JSON output formatted for Puppet, Ansible, Chef...
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--batch nrpe Produce machine readable output formatted for NRPE
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--variant [1,2,3] Specify which variant you'd like to check, by default all variants are checked
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Can be specified multiple times (e.g. --variant 2 --variant 3)
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Return codes:
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0 (not vulnerable), 2 (vulnerable), 3 (unknown), 255 (error)
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IMPORTANT:
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A false sense of security is worse than no security at all.
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Please use the --disclaimer option to understand exactly what this script does.
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EOF
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}
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show_disclaimer()
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{
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cat <<EOF
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Disclaimer:
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This tool does its best to determine whether your system is immune (or has proper mitigations in place) for the
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collectively named "speculative execution" vulnerabilities. It doesn't attempt to run any kind of exploit, and can't guarantee
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that your system is secure, but rather helps you verifying whether your system has the known correct mitigations in place.
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However, some mitigations could also exist in your kernel that this script doesn't know (yet) how to detect, or it might
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falsely detect mitigations that in the end don't work as expected (for example, on backported or modified kernels).
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Your system exposure also depends on your CPU. As of now, AMD and ARM processors are marked as immune to some or all of these
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vulnerabilities (except some specific ARM models). All Intel processors manufactured since circa 1995 are thought to be vulnerable.
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Whatever processor one uses, one might seek more information from the manufacturer of that processor and/or of the device
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in which it runs.
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The nature of the discovered vulnerabilities being quite new, the landscape of vulnerable processors can be expected
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to change over time, which is why this script makes the assumption that all CPUs are vulnerable, except if the manufacturer
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explicitly stated otherwise in a verifiable public announcement.
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This tool has been released in the hope that it'll be useful, but don't use it to jump to conclusions about your security.
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EOF
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}
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# parse options
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opt_kernel=''
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opt_config=''
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opt_map=''
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opt_live_explicit=0
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opt_live=1
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opt_no_color=0
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opt_batch=0
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opt_batch_format="text"
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opt_verbose=1
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opt_variant1=0
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opt_variant2=0
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opt_variant3=0
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opt_allvariants=1
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opt_no_sysfs=0
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opt_sysfs_only=0
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opt_coreos=0
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global_critical=0
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global_unknown=0
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nrpe_vuln=""
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# find a sane `echo` command
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# we'll try to avoid using shell builtins that might not take options
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if which echo >/dev/null 2>&1; then
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echo_cmd=$(which echo)
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else
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[ -x /bin/echo ] && echo_cmd=/bin/echo
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[ -x /system/bin/echo ] && echo_cmd=/system/bin/echo
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fi
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# still empty ? fallback to builtin
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[ -z "$echo_cmd" ] && echo_cmd=echo
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__echo()
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{
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opt="$1"
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shift
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_msg="$*"
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if [ "$opt_no_color" = 1 ] ; then
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# strip ANSI color codes
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_msg=$($echo_cmd -e "$_msg" | sed -r "s/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[m|K]//g")
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fi
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# shellcheck disable=SC2086
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$echo_cmd $opt -e "$_msg"
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}
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_echo()
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{
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if [ "$opt_verbose" -ge "$1" ]; then
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shift
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__echo '' "$*"
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fi
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}
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_echo_nol()
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{
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if [ "$opt_verbose" -ge "$1" ]; then
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shift
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__echo -n "$*"
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fi
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}
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_warn()
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{
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_echo 0 "\033[31m$*\033[0m" >&2
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}
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_info()
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{
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_echo 1 "$*"
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}
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_info_nol()
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{
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_echo_nol 1 "$*"
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}
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_verbose()
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{
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_echo 2 "$*"
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}
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_verbose_nol()
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{
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_echo_nol 2 "$*"
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}
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_debug()
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{
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_echo 3 "\033[34m(debug) $*\033[0m"
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}
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is_cpu_vulnerable_cached=0
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_is_cpu_vulnerable_cached()
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{
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# shellcheck disable=SC2086
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[ "$1" = 1 ] && return $variant1
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# shellcheck disable=SC2086
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[ "$1" = 2 ] && return $variant2
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# shellcheck disable=SC2086
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[ "$1" = 3 ] && return $variant3
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echo "$0: error: invalid variant '$1' passed to is_cpu_vulnerable()" >&2
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exit 255
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}
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is_cpu_vulnerable()
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{
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# param: 1, 2 or 3 (variant)
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# returns 0 if vulnerable, 1 if not vulnerable
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# (note that in shell, a return of 0 is success)
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# by default, everything is vulnerable, we work in a "whitelist" logic here.
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# usage: is_cpu_vulnerable 2 && do something if vulnerable
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if [ "$is_cpu_vulnerable_cached" = 1 ]; then
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_is_cpu_vulnerable_cached "$1"
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return $?
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fi
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variant1=''
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variant2=''
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variant3=''
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# we also set a friendly name for the CPU to be used in the script if needed
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cpu_friendly_name=$(grep '^model name' /proc/cpuinfo | cut -d: -f2- | head -1 | sed -e 's/^ *//')
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# variant 0 is just for us to fill the cpu_friendly_name var
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[ "$1" = 0 ] && return 0
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if grep -q GenuineIntel /proc/cpuinfo; then
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# Intel
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# Old Atoms are not vulnerable to spectre 2 nor meltdown
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# https://security-center.intel.com/advisory.aspx?intelid=INTEL-SA-00088&languageid=en-fr
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# model name : Genuine Intel(R) CPU N270 @ 1.60GHz
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# model name : Intel(R) Atom(TM) CPU N270 @ 1.60GHz
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# model name : Intel(R) Atom(TM) CPU 330 @ 1.60GHz
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if grep -qE '^model name.+ Intel\(R\) (Atom\(TM\) CPU +(S|D|N|230|330)|CPU N[0-9]{3} )' /proc/cpuinfo; then
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variant1=vuln
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[ -z "$variant2" ] && variant2=immune
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[ -z "$variant3" ] && variant3=immune
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# https://github.com/crozone/SpectrePoC/issues/1 ^F E5200 => spectre 2 not vulnerable
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# https://github.com/paboldin/meltdown-exploit/issues/19 ^F E5200 => meltdown vulnerable
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# model name : Pentium(R) Dual-Core CPU E5200 @ 2.50GHz
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elif grep -qE '^model name.+ Pentium\(R\) Dual-Core[[:space:]]+CPU[[:space:]]+E[0-9]{4}K? ' /proc/cpuinfo; then
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variant1=vuln
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[ -z "$variant2" ] && variant2=immune
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variant3=vuln
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fi
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if [ "$capabilities_rdcl_no" = 1 ]; then
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# capability bit for future Intel processor that will explicitly state
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# that they're not vulnerable to Meltdown
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# this var is set in check_cpu()
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variant3=immune
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_debug "is_cpu_vulnerable: RDCL_NO is set so not vuln to meltdown"
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fi
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elif grep -q AuthenticAMD /proc/cpuinfo; then
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# AMD revised their statement about variant2 => vulnerable
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# https://www.amd.com/en/corporate/speculative-execution
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variant1=vuln
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variant2=vuln
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[ -z "$variant3" ] && variant3=immune
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elif grep -qi 'CPU implementer[[:space:]]*:[[:space:]]*0x41' /proc/cpuinfo; then
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# ARM
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# reference: https://developer.arm.com/support/security-update
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# some devices (phones or other) have several ARMs and as such different part numbers,
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# an example is "bigLITTLE". we shouldn't rely on the first CPU only, so we check the whole list
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cpupart_list=$(awk '/CPU part/ {print $4}' /proc/cpuinfo)
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cpuarch_list=$(awk '/CPU architecture/ {print $3}' /proc/cpuinfo)
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i=0
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for cpupart in $cpupart_list
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do
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i=$(( i + 1 ))
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cpuarch=$(echo "$cpuarch_list" | awk '{ print $'$i' }')
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_debug "checking cpu$i: <$cpupart> <$cpuarch>"
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# some kernels report AArch64 instead of 8
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[ "$cpuarch" = "AArch64" ] && cpuarch=8
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if [ -n "$cpupart" ] && [ -n "$cpuarch" ]; then
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cpu_friendly_name="ARM v$cpuarch model $cpupart"
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# Cortex-R7 and Cortex-R8 are real-time and only used in medical devices or such
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# I can't find their CPU part number, but it's probably not that useful anyway
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# model R7 R8 A9 A15 A17 A57 A72 A73 A75
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# part ? ? 0xc09 0xc0f 0xc0e 0xd07 0xd08 0xd09 0xd0a
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# arch 7? 7? 7 7 7 8 8 8 8
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#
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# variant 1 & variant 2
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if [ "$cpuarch" = 7 ] && echo "$cpupart" | grep -Eq '^0x(c09|c0f|c0e)$'; then
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# armv7 vulnerable chips
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_debug "checking cpu$i: this armv7 vulnerable to spectre 1 & 2"
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variant1=vuln
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variant2=vuln
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elif [ "$cpuarch" = 8 ] && echo "$cpupart" | grep -Eq '^0x(d07|d08|d09|d0a)$'; then
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# armv8 vulnerable chips
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_debug "checking cpu$i: this armv8 vulnerable to spectre 1 & 2"
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variant1=vuln
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variant2=vuln
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else
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_debug "checking cpu$i: this arm non vulnerable to 1 & 2"
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# others are not vulnerable
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[ -z "$variant1" ] && variant1=immune
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[ -z "$variant2" ] && variant2=immune
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fi
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# for variant3, only A75 is vulnerable
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if [ "$cpuarch" = 8 ] && [ "$cpupart" = 0xd0a ]; then
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_debug "checking cpu$i: arm A75 vulnerable to meltdown"
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variant3=vuln
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else
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_debug "checking cpu$i: this arm non vulnerable to meltdown"
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[ -z "$variant3" ] && variant3=immune
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fi
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fi
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_debug "is_cpu_vulnerable: for cpu$i and so far, we have <$variant1> <$variant2> <$variant3>"
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done
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fi
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_debug "is_cpu_vulnerable: temp results are <$variant1> <$variant2> <$variant3>"
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# if at least one of the cpu is vulnerable, then the system is vulnerable
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[ "$variant1" = "immune" ] && variant1=1 || variant1=0
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[ "$variant2" = "immune" ] && variant2=1 || variant2=0
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[ "$variant3" = "immune" ] && variant3=1 || variant3=0
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_debug "is_cpu_vulnerable: final results are <$variant1> <$variant2> <$variant3>"
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is_cpu_vulnerable_cached=1
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_is_cpu_vulnerable_cached "$1"
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return $?
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}
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show_header()
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{
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_info "\033[1;34mSpectre and Meltdown mitigation detection tool v$VERSION\033[0m"
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_info
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}
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parse_opt_file()
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{
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# parse_opt_file option_name option_value
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option_name="$1"
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option_value="$2"
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if [ -z "$option_value" ]; then
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show_header
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show_usage
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echo "$0: error: --$option_name expects one parameter (a file)" >&2
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exit 1
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elif [ ! -e "$option_value" ]; then
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show_header
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echo "$0: error: couldn't find file $option_value" >&2
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exit 1
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elif [ ! -f "$option_value" ]; then
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show_header
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echo "$0: error: $option_value is not a file" >&2
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exit 1
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elif [ ! -r "$option_value" ]; then
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show_header
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echo "$0: error: couldn't read $option_value (are you root?)" >&2
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exit 1
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fi
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echo "$option_value"
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exit 0
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}
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while [ -n "$1" ]; do
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if [ "$1" = "--kernel" ]; then
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opt_kernel=$(parse_opt_file kernel "$2"); ret=$?
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[ $ret -ne 0 ] && exit 255
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shift 2
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opt_live=0
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elif [ "$1" = "--config" ]; then
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opt_config=$(parse_opt_file config "$2"); ret=$?
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[ $ret -ne 0 ] && exit 255
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shift 2
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opt_live=0
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elif [ "$1" = "--map" ]; then
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opt_map=$(parse_opt_file map "$2"); ret=$?
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[ $ret -ne 0 ] && exit 255
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shift 2
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opt_live=0
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elif [ "$1" = "--live" ]; then
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opt_live_explicit=1
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shift
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elif [ "$1" = "--no-color" ]; then
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opt_no_color=1
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shift
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elif [ "$1" = "--no-sysfs" ]; then
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opt_no_sysfs=1
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shift
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elif [ "$1" = "--sysfs-only" ]; then
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opt_sysfs_only=1
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shift
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elif [ "$1" = "--coreos" ]; then
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opt_coreos=1
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shift
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elif [ "$1" = "--coreos-within-toolbox" ]; then
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# don't use directly: used internally by --coreos
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opt_coreos=0
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shift
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elif [ "$1" = "--batch" ]; then
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opt_batch=1
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opt_verbose=0
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shift
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case "$1" in
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text|nrpe|json) opt_batch_format="$1"; shift;;
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--*) ;; # allow subsequent flags
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'') ;; # allow nothing at all
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*)
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echo "$0: error: unknown batch format '$1'" >&2
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echo "$0: error: --batch expects a format from: text, nrpe, json" >&2
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exit 255
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;;
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esac
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elif [ "$1" = "-v" ] || [ "$1" = "--verbose" ]; then
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opt_verbose=$(( opt_verbose + 1 ))
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shift
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elif [ "$1" = "--variant" ]; then
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if [ -z "$2" ]; then
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echo "$0: error: option --variant expects a parameter (1, 2 or 3)" >&2
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exit 255
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fi
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case "$2" in
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1) opt_variant1=1; opt_allvariants=0;;
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2) opt_variant2=1; opt_allvariants=0;;
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3) opt_variant3=1; opt_allvariants=0;;
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*)
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echo "$0: error: invalid parameter '$2' for --variant, expected either 1, 2 or 3" >&2;
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exit 255
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;;
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esac
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shift 2
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elif [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
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show_header
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show_usage
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exit 0
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elif [ "$1" = "--version" ]; then
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opt_no_color=1
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show_header
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exit 0
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elif [ "$1" = "--disclaimer" ]; then
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show_header
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show_disclaimer
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exit 0
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else
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show_header
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show_usage
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echo "$0: error: unknown option '$1'"
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exit 255
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fi
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done
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show_header
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|
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if [ "$opt_no_sysfs" = 1 ] && [ "$opt_sysfs_only" = 1 ]; then
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_warn "Incompatible options specified (--no-sysfs and --sysfs-only), aborting"
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exit 255
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fi
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# print status function
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pstatus()
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{
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if [ "$opt_no_color" = 1 ]; then
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_info_nol "$2"
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else
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case "$1" in
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red) col="\033[41m\033[30m";;
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green) col="\033[42m\033[30m";;
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yellow) col="\033[43m\033[30m";;
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blue) col="\033[44m\033[30m";;
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*) col="";;
|
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esac
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_info_nol "$col $2 \033[0m"
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fi
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[ -n "$3" ] && _info_nol " ($3)"
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_info
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}
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|
|
# Print the final status of a vulnerability (incl. batch mode)
|
|
# Arguments are: CVE UNK/OK/VULN description
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|
pvulnstatus()
|
|
{
|
|
if [ "$opt_batch" = 1 ]; then
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|
case "$opt_batch_format" in
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text) _echo 0 "$1: $2 ($3)";;
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json)
|
|
case "$1" in
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CVE-2017-5753) aka="SPECTRE VARIANT 1";;
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CVE-2017-5715) aka="SPECTRE VARIANT 2";;
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CVE-2017-5754) aka="MELTDOWN";;
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esac
|
|
case "$2" in
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UNK) is_vuln="null";;
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VULN) is_vuln="true";;
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OK) is_vuln="false";;
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esac
|
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json_output="${json_output:-[}{\"NAME\":\"$aka\",\"CVE\":\"$1\",\"VULNERABLE\":$is_vuln,\"INFOS\":\"$3\"},"
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;;
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|
|
nrpe) [ "$2" = VULN ] && nrpe_vuln="$nrpe_vuln $1";;
|
|
esac
|
|
fi
|
|
|
|
# always fill global_* vars because we use that do decide the program exit code
|
|
case "$2" in
|
|
UNK) global_unknown="1";;
|
|
VULN) global_critical="1";;
|
|
esac
|
|
|
|
# display info if we're not in quiet/batch mode
|
|
vulnstatus="$2"
|
|
shift 2
|
|
_info_nol "> \033[46m\033[30mSTATUS:\033[0m "
|
|
case "$vulnstatus" in
|
|
UNK) pstatus yellow 'UNKNOWN' "$@";;
|
|
VULN) pstatus red 'VULNERABLE' "$@";;
|
|
OK) pstatus green 'NOT VULNERABLE' "$@";;
|
|
esac
|
|
}
|
|
|
|
|
|
# The 3 below functions are taken from the extract-linux script, available here:
|
|
# https://github.com/torvalds/linux/blob/master/scripts/extract-vmlinux
|
|
# The functions have been modified for better integration to this script
|
|
# The original header of the file has been retained below
|
|
|
|
# ----------------------------------------------------------------------
|
|
# extract-vmlinux - Extract uncompressed vmlinux from a kernel image
|
|
#
|
|
# Inspired from extract-ikconfig
|
|
# (c) 2009,2010 Dick Streefland <dick@streefland.net>
|
|
#
|
|
# (c) 2011 Corentin Chary <corentin.chary@gmail.com>
|
|
#
|
|
# Licensed under the GNU General Public License, version 2 (GPLv2).
|
|
# ----------------------------------------------------------------------
|
|
|
|
vmlinux=''
|
|
vmlinux_err=''
|
|
check_vmlinux()
|
|
{
|
|
readelf -h "$1" >/dev/null 2>&1 && return 0
|
|
return 1
|
|
}
|
|
|
|
try_decompress()
|
|
{
|
|
# The obscure use of the "tr" filter is to work around older versions of
|
|
# "grep" that report the byte offset of the line instead of the pattern.
|
|
|
|
# Try to find the header ($1) and decompress from here
|
|
for pos in $(tr "$1\n$2" "\n$2=" < "$6" | grep -abo "^$2")
|
|
do
|
|
_debug "try_decompress: magic for $3 found at offset $pos"
|
|
if ! which "$3" >/dev/null 2>&1; then
|
|
vmlinux_err="missing '$3' tool, please install it, usually it's in the '$5' package"
|
|
return 0
|
|
fi
|
|
pos=${pos%%:*}
|
|
# shellcheck disable=SC2086
|
|
tail -c+$pos "$6" 2>/dev/null | $3 $4 > "$vmlinuxtmp" 2>/dev/null
|
|
if check_vmlinux "$vmlinuxtmp"; then
|
|
vmlinux="$vmlinuxtmp"
|
|
_debug "try_decompress: decompressed with $3 successfully!"
|
|
return 0
|
|
else
|
|
_debug "try_decompress: decompression with $3 did not work"
|
|
fi
|
|
done
|
|
return 1
|
|
}
|
|
|
|
extract_vmlinux()
|
|
{
|
|
[ -n "$1" ] || return 1
|
|
# Prepare temp files:
|
|
vmlinuxtmp="$(mktemp /tmp/vmlinux-XXXXXX)"
|
|
# single quotes in trap cmd: will be expanded when signalled
|
|
trap 'rm -f $vmlinuxtmp' EXIT INT
|
|
|
|
# Initial attempt for uncompressed images or objects:
|
|
if check_vmlinux "$1"; then
|
|
cat "$1" > "$vmlinuxtmp"
|
|
vmlinux=$vmlinuxtmp
|
|
return 0
|
|
fi
|
|
|
|
# That didn't work, so retry after decompression.
|
|
try_decompress '\037\213\010' xy gunzip '' gunzip "$1" && return 0
|
|
try_decompress '\3757zXZ\000' abcde unxz '' xz-utils "$1" && return 0
|
|
try_decompress 'BZh' xy bunzip2 '' bzip2 "$1" && return 0
|
|
try_decompress '\135\0\0\0' xxx unlzma '' xz-utils "$1" && return 0
|
|
try_decompress '\211\114\132' xy 'lzop' '-d' lzop "$1" && return 0
|
|
try_decompress '\002\041\114\030' xyy 'lz4' '-d -l' liblz4-tool "$1" && return 0
|
|
return 1
|
|
}
|
|
|
|
# end of extract-vmlinux functions
|
|
|
|
mount_debugfs()
|
|
{
|
|
if [ ! -e /sys/kernel/debug/sched_features ]; then
|
|
# try to mount the debugfs hierarchy ourselves and remember it to umount afterwards
|
|
mount -t debugfs debugfs /sys/kernel/debug 2>/dev/null && mounted_debugfs=1
|
|
fi
|
|
}
|
|
|
|
umount_debugfs()
|
|
{
|
|
if [ "$mounted_debugfs" = 1 ]; then
|
|
# umount debugfs if we did mount it ourselves
|
|
umount /sys/kernel/debug
|
|
fi
|
|
}
|
|
|
|
load_msr()
|
|
{
|
|
modprobe msr 2>/dev/null && insmod_msr=1
|
|
_debug "attempted to load module msr, insmod_msr=$insmod_msr"
|
|
}
|
|
|
|
unload_msr()
|
|
{
|
|
if [ "$insmod_msr" = 1 ]; then
|
|
# if we used modprobe ourselves, rmmod the module
|
|
rmmod msr 2>/dev/null
|
|
_debug "attempted to unload module msr, ret=$?"
|
|
fi
|
|
}
|
|
|
|
load_cpuid()
|
|
{
|
|
modprobe cpuid 2>/dev/null && insmod_cpuid=1
|
|
_debug "attempted to load module cpuid, insmod_cpuid=$insmod_cpuid"
|
|
}
|
|
|
|
unload_cpuid()
|
|
{
|
|
if [ "$insmod_cpuid" = 1 ]; then
|
|
# if we used modprobe ourselves, rmmod the module
|
|
rmmod cpuid 2>/dev/null
|
|
_debug "attempted to unload module cpuid, ret=$?"
|
|
fi
|
|
}
|
|
|
|
dmesg_grep()
|
|
{
|
|
# grep for something in dmesg, ensuring that the dmesg buffer
|
|
# has not been truncated
|
|
dmesg_grepped=''
|
|
if ! dmesg | grep -qE '(^|\] )Linux version [0-9]'; then
|
|
# dmesg truncated
|
|
return 2
|
|
fi
|
|
dmesg_grepped=$(dmesg | grep -E "$1" | head -1)
|
|
# not found:
|
|
[ -z "$dmesg_grepped" ] && return 1
|
|
# found, output is in $dmesg_grepped
|
|
return 0
|
|
}
|
|
|
|
is_coreos()
|
|
{
|
|
which coreos-install >/dev/null 2>&1 && which toolbox >/dev/null 2>&1 && return 0
|
|
return 1
|
|
}
|
|
|
|
is_ucode_blacklisted()
|
|
{
|
|
# if it's not an Intel, don't bother: it's not blacklisted
|
|
grep -q GenuineIntel /proc/cpuinfo || return 1
|
|
# it also needs to be family=6
|
|
grep -qE '^cpu family.+ 6$' /proc/cpuinfo || return 1
|
|
cpu_model=$( grep '^model' /proc/cpuinfo | awk '{print $3}' | grep -E '^[0-9]+$' | head -1)
|
|
cpu_stepping=$(grep '^stepping' /proc/cpuinfo | awk '{print $3}' | grep -E '^[0-9]+$' | head -1)
|
|
cpu_ucode=$(grep '^microcode' /proc/cpuinfo | awk '{print $3}' | head -1)
|
|
# now, check each known bad microcode
|
|
# source: http://lkml.iu.edu/hypermail/linux/kernel/1801.2/06349.html
|
|
INTEL_FAM6_KABYLAKE_DESKTOP=158
|
|
INTEL_FAM6_KABYLAKE_MOBILE=142
|
|
INTEL_FAM6_SKYLAKE_X=85
|
|
INTEL_FAM6_SKYLAKE_MOBILE=78
|
|
INTEL_FAM6_SKYLAKE_DESKTOP=94
|
|
INTEL_FAM6_BROADWELL_CORE=61
|
|
INTEL_FAM6_BROADWELL_GT3E=71
|
|
INTEL_FAM6_HASWELL_ULT=69
|
|
INTEL_FAM6_HASWELL_GT3E=70
|
|
INTEL_FAM6_HASWELL_CORE=60
|
|
INTEL_FAM6_IVYBRIDGE_X=62
|
|
INTEL_FAM6_HASWELL_X=63
|
|
INTEL_FAM6_BROADWELL_XEON_D=86
|
|
INTEL_FAM6_BROADWELL_GT3E=71
|
|
INTEL_FAM6_BROADWELL_X=79
|
|
# model,stepping,microcode
|
|
for tuple in \
|
|
$INTEL_FAM6_KABYLAKE_DESKTOP,0x0B,0x80 \
|
|
$INTEL_FAM6_KABYLAKE_MOBILE,0x0A,0x80 \
|
|
$INTEL_FAM6_KABYLAKE_MOBILE,0x09,0x80 \
|
|
$INTEL_FAM6_KABYLAKE_DESKTOP,0x09,0x80 \
|
|
$INTEL_FAM6_SKYLAKE_X,0x04,0x0200003C \
|
|
$INTEL_FAM6_SKYLAKE_MOBILE,0x03,0x000000C2 \
|
|
$INTEL_FAM6_SKYLAKE_DESKTOP,0x03,0x000000C2 \
|
|
$INTEL_FAM6_BROADWELL_CORE,0x04,0x28 \
|
|
$INTEL_FAM6_BROADWELL_GT3E,0x01,0x0000001B \
|
|
$INTEL_FAM6_HASWELL_ULT,0x01,0x21 \
|
|
$INTEL_FAM6_HASWELL_GT3E,0x01,0x18 \
|
|
$INTEL_FAM6_HASWELL_CORE,0x03,0x23 \
|
|
$INTEL_FAM6_IVYBRIDGE_X,0x04,0x42a \
|
|
$INTEL_FAM6_HASWELL_X,0x02,0x3b \
|
|
$INTEL_FAM6_HASWELL_X,0x04,0x10 \
|
|
$INTEL_FAM6_HASWELL_CORE,0x03,0x23 \
|
|
$INTEL_FAM6_BROADWELL_XEON_D,0x02,0x14 \
|
|
$INTEL_FAM6_BROADWELL_XEON_D,0x03,0x7000011 \
|
|
$INTEL_FAM6_BROADWELL_GT3E,0x01,0x0000001B \
|
|
$INTEL_FAM6_BROADWELL_X,0x01,0x0b000025 \
|
|
$INTEL_FAM6_KABYLAKE_DESKTOP,0x09,0x80 \
|
|
$INTEL_FAM6_SKYLAKE_X,0x03,0x100013e \
|
|
$INTEL_FAM6_SKYLAKE_X,0x04,0x200003c
|
|
do
|
|
model=$(echo $tuple | cut -d, -f1)
|
|
stepping=$(( $(echo $tuple | cut -d, -f2) ))
|
|
ucode=$(echo $tuple | cut -d, -f3)
|
|
if [ "$cpu_model" = "$model" ] && [ "$cpu_stepping" = "$stepping" ] && echo "$cpu_ucode" | grep -qi "^$ucode$"; then
|
|
_debug "is_ucode_blacklisted: we have a match! ($cpu_model/$cpu_stepping/$cpu_ucode)"
|
|
bad_ucode_found="Intel CPU Family 6 Model $cpu_model Stepping $cpu_stepping with microcode $cpu_ucode"
|
|
return 0
|
|
fi
|
|
done
|
|
_debug "is_ucode_blacklisted: no ($cpu_model/$cpu_stepping/$cpu_ucode)"
|
|
return 1
|
|
}
|
|
|
|
# check for mode selection inconsistency
|
|
if [ "$opt_live_explicit" = 1 ]; then
|
|
if [ -n "$opt_kernel" ] || [ -n "$opt_config" ] || [ -n "$opt_map" ]; then
|
|
show_usage
|
|
echo "$0: error: incompatible modes specified, use either --live or --kernel/--config/--map" >&2
|
|
exit 255
|
|
fi
|
|
fi
|
|
|
|
# coreos mode
|
|
if [ "$opt_coreos" = 1 ]; then
|
|
if ! is_coreos; then
|
|
_warn "CoreOS mode asked, but we're not under CoreOS!"
|
|
exit 255
|
|
fi
|
|
_warn "CoreOS mode, starting an ephemeral toolbox to launch the script"
|
|
load_msr
|
|
load_cpuid
|
|
mount_debugfs
|
|
toolbox --ephemeral --bind-ro /dev/cpu:/dev/cpu -- sh -c "dnf install -y binutils which && /media/root$PWD/$0 $* --coreos-within-toolbox"
|
|
exitcode=$?
|
|
mount_debugfs
|
|
unload_cpuid
|
|
unload_msr
|
|
exit $exitcode
|
|
else
|
|
if is_coreos; then
|
|
_warn "You seem to be running CoreOS, you might want to use the --coreos option for better results"
|
|
_warn
|
|
fi
|
|
fi
|
|
|
|
# root check (only for live mode, for offline mode, we already checked if we could read the files)
|
|
|
|
if [ "$opt_live" = 1 ]; then
|
|
if [ "$(id -u)" -ne 0 ]; then
|
|
_warn "Note that you should launch this script with root privileges to get accurate information."
|
|
_warn "We'll proceed but you might see permission denied errors."
|
|
_warn "To run it as root, you can try the following command: sudo $0"
|
|
_warn
|
|
fi
|
|
_info "Checking for vulnerabilities on current system"
|
|
_info "Kernel is \033[35m$(uname -s) $(uname -r) $(uname -v) $(uname -m)\033[0m"
|
|
# call is_cpu_vulnerable to fill the cpu_friendly_name var
|
|
is_cpu_vulnerable 0
|
|
_info "CPU is \033[35m$cpu_friendly_name\033[0m"
|
|
|
|
# try to find the image of the current running kernel
|
|
# first, look for the BOOT_IMAGE hint in the kernel cmdline
|
|
if [ -r /proc/cmdline ] && grep -q 'BOOT_IMAGE=' /proc/cmdline; then
|
|
opt_kernel=$(grep -Eo 'BOOT_IMAGE=[^ ]+' /proc/cmdline | cut -d= -f2)
|
|
_debug "found opt_kernel=$opt_kernel in /proc/cmdline"
|
|
# if we have a dedicated /boot partition, our bootloader might have just called it /
|
|
# so try to prepend /boot and see if we find anything
|
|
[ -e "/boot/$opt_kernel" ] && opt_kernel="/boot/$opt_kernel"
|
|
# special case for CoreOS if we're inside the toolbox
|
|
[ -e "/media/root/boot/$opt_kernel" ] && opt_kernel="/media/root/boot/$opt_kernel"
|
|
_debug "opt_kernel is now $opt_kernel"
|
|
# else, the full path is already there (most probably /boot/something)
|
|
fi
|
|
# if we didn't find a kernel, default to guessing
|
|
if [ ! -e "$opt_kernel" ]; then
|
|
# Fedora:
|
|
[ -e "/lib/modules/$(uname -r)/vmlinuz" ] && opt_kernel="/lib/modules/$(uname -r)/vmlinuz"
|
|
# Slackare:
|
|
[ -e "/boot/vmlinuz" ] && opt_kernel="/boot/vmlinuz"
|
|
# Arch:
|
|
[ -e "/boot/vmlinuz-linux" ] && opt_kernel="/boot/vmlinuz-linux"
|
|
# Linux-Libre:
|
|
[ -e "/boot/vmlinuz-linux-libre" ] && opt_kernel="/boot/vmlinuz-linux-libre"
|
|
# generic:
|
|
[ -e "/boot/vmlinuz-$(uname -r)" ] && opt_kernel="/boot/vmlinuz-$(uname -r)"
|
|
[ -e "/boot/kernel-$( uname -r)" ] && opt_kernel="/boot/kernel-$( uname -r)"
|
|
[ -e "/boot/bzImage-$(uname -r)" ] && opt_kernel="/boot/bzImage-$(uname -r)"
|
|
# Gentoo:
|
|
[ -e "/boot/kernel-genkernel-$(uname -m)-$(uname -r)" ] && opt_kernel="/boot/kernel-genkernel-$(uname -m)-$(uname -r)"
|
|
# NixOS:
|
|
[ -e "/run/booted-system/kernel" ] && opt_kernel="/run/booted-system/kernel"
|
|
fi
|
|
|
|
# system.map
|
|
if [ -e /proc/kallsyms ] ; then
|
|
opt_map=/proc/kallsyms
|
|
elif [ -e "/lib/modules/$(uname -r)/System.map" ] ; then
|
|
opt_map="/lib/modules/$(uname -r)/System.map"
|
|
elif [ -e "/boot/System.map-$(uname -r)" ] ; then
|
|
opt_map="/boot/System.map-$(uname -r)"
|
|
fi
|
|
|
|
# config
|
|
if [ -e /proc/config.gz ] ; then
|
|
dumped_config="$(mktemp /tmp/config-XXXXXX)"
|
|
gunzip -c /proc/config.gz > "$dumped_config"
|
|
# dumped_config will be deleted at the end of the script
|
|
opt_config="$dumped_config"
|
|
elif [ -e "/lib/modules/$(uname -r)/config" ]; then
|
|
opt_config="/lib/modules/$(uname -r)/config"
|
|
elif [ -e "/boot/config-$(uname -r)" ]; then
|
|
opt_config="/boot/config-$(uname -r)"
|
|
fi
|
|
else
|
|
_info "Checking for vulnerabilities against specified kernel"
|
|
fi
|
|
|
|
if [ -n "$opt_kernel" ]; then
|
|
_verbose "Will use vmlinux image \033[35m$opt_kernel\033[0m"
|
|
else
|
|
_verbose "Will use no vmlinux image (accuracy might be reduced)"
|
|
bad_accuracy=1
|
|
fi
|
|
|
|
if [ -n "$opt_config" ] && ! grep -q '^CONFIG_' "$opt_config"; then
|
|
# given file is invalid!
|
|
_warn "The kernel config file seems invalid, was expecting a plain-text file, ignoring it!"
|
|
opt_config=''
|
|
fi
|
|
|
|
if [ -n "$dumped_config" ] && [ -n "$opt_config" ]; then
|
|
_verbose "Will use kconfig \033[35m/proc/config.gz (decompressed)\033[0m"
|
|
elif [ -n "$opt_config" ]; then
|
|
_verbose "Will use kconfig \033[35m$opt_config\033[0m"
|
|
else
|
|
_verbose "Will use no kconfig (accuracy might be reduced)"
|
|
bad_accuracy=1
|
|
fi
|
|
|
|
if [ -n "$opt_map" ]; then
|
|
_verbose "Will use System.map file \033[35m$opt_map\033[0m"
|
|
else
|
|
_verbose "Will use no System.map file (accuracy might be reduced)"
|
|
bad_accuracy=1
|
|
fi
|
|
|
|
if [ "$bad_accuracy" = 1 ]; then
|
|
_info "We're missing some kernel info (see -v), accuracy might be reduced"
|
|
fi
|
|
|
|
if [ -e "$opt_kernel" ]; then
|
|
if ! which readelf >/dev/null 2>&1; then
|
|
_debug "readelf not found"
|
|
vmlinux_err="missing 'readelf' tool, please install it, usually it's in the 'binutils' package"
|
|
else
|
|
extract_vmlinux "$opt_kernel"
|
|
fi
|
|
else
|
|
_debug "no opt_kernel defined"
|
|
vmlinux_err="couldn't find your kernel image in /boot, if you used netboot, this is normal"
|
|
fi
|
|
if [ -z "$vmlinux" ] || [ ! -r "$vmlinux" ]; then
|
|
[ -z "$vmlinux_err" ] && vmlinux_err="couldn't extract your kernel from $opt_kernel"
|
|
fi
|
|
|
|
_info
|
|
|
|
# end of header stuff
|
|
|
|
# now we define some util functions and the check_*() funcs, as
|
|
# the user can choose to execute only some of those
|
|
|
|
sys_interface_check()
|
|
{
|
|
[ "$opt_live" = 1 ] && [ "$opt_no_sysfs" = 0 ] && [ -r "$1" ] || return 1
|
|
_info_nol "* Mitigated according to the /sys interface: "
|
|
if grep -qi '^not affected' "$1"; then
|
|
# Not affected
|
|
status=OK
|
|
pstatus green YES "kernel confirms that your CPU is unaffected"
|
|
elif grep -qi '^mitigation' "$1"; then
|
|
# Mitigation: PTI
|
|
status=OK
|
|
pstatus green YES "kernel confirms that the mitigation is active"
|
|
elif grep -qi '^vulnerable' "$1"; then
|
|
# Vulnerable
|
|
status=VULN
|
|
pstatus red NO "kernel confirms your system is vulnerable"
|
|
else
|
|
status=UNK
|
|
pstatus yellow UNKNOWN "unknown value reported by kernel"
|
|
fi
|
|
msg=$(cat "$1")
|
|
_debug "sys_interface_check: $1=$msg"
|
|
return 0
|
|
}
|
|
|
|
check_cpu()
|
|
{
|
|
_info "\033[1;34mHardware check\033[0m"
|
|
|
|
_info "* Hardware support (CPU microcode) for mitigation techniques"
|
|
_info " * Indirect Branch Restricted Speculation (IBRS)"
|
|
_info_nol " * SPEC_CTRL MSR is available: "
|
|
if [ ! -e /dev/cpu/0/msr ]; then
|
|
# try to load the module ourselves (and remember it so we can rmmod it afterwards)
|
|
load_msr
|
|
fi
|
|
if [ ! -e /dev/cpu/0/msr ]; then
|
|
spec_ctrl_msr=-1
|
|
pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/msr, is msr support enabled in your kernel?"
|
|
else
|
|
# the new MSR 'SPEC_CTRL' is at offset 0x48
|
|
# here we use dd, it's the same as using 'rdmsr 0x48' but without needing the rdmsr tool
|
|
# if we get a read error, the MSR is not there. bs has to be 8 for msr
|
|
# skip=9 because 8*9=72=0x48
|
|
dd if=/dev/cpu/0/msr of=/dev/null bs=8 count=1 skip=9 2>/dev/null; ret=$?
|
|
if [ $ret -eq 0 ]; then
|
|
spec_ctrl_msr=1
|
|
pstatus green YES
|
|
else
|
|
spec_ctrl_msr=0
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
|
|
_info_nol " * CPU indicates IBRS capability: "
|
|
if [ ! -e /dev/cpu/0/cpuid ]; then
|
|
# try to load the module ourselves (and remember it so we can rmmod it afterwards)
|
|
load_cpuid
|
|
fi
|
|
if [ ! -e /dev/cpu/0/cpuid ]; then
|
|
pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/cpuid, is cpuid support enabled in your kernel?"
|
|
else
|
|
# from kernel src: { X86_FEATURE_SPEC_CTRL, CPUID_EDX,26, 0x00000007, 0 },
|
|
if [ "$opt_verbose" -ge 3 ]; then
|
|
dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 >/dev/null 2>/dev/null
|
|
_debug "cpuid: reading leaf7 of cpuid on cpu0, ret=$?"
|
|
_debug "cpuid: leaf7 eax-ebx-ecx-edx: $(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | od -x -A n)"
|
|
_debug "cpuid: leaf7 edx higher byte is: $(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | dd bs=1 skip=15 count=1 2>/dev/null | od -x -A n)"
|
|
fi
|
|
# getting high byte of edx on leaf7 of cpuinfo in decimal
|
|
edx_hb=$(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | dd bs=1 skip=15 count=1 2>/dev/null | od -t u -A n | awk '{print $1}')
|
|
_debug "cpuid: leaf7 edx higher byte: $edx_hb (decimal)"
|
|
edx_bit26=$(( edx_hb & 4 ))
|
|
_debug "cpuid: edx_bit26=$edx_bit26"
|
|
if [ "$edx_bit26" -eq 4 ]; then
|
|
pstatus green YES "SPEC_CTRL feature bit"
|
|
cpuid_spec_ctrl=1
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
|
|
# hardware support according to kernel
|
|
if [ "$opt_verbose" -ge 2 ]; then
|
|
# the spec_ctrl flag in cpuinfo is set if and only if the kernel sees
|
|
# that the spec_ctrl cpuinfo bit set. we already check that ourselves above
|
|
# but let's check it anyway (in verbose mode only)
|
|
_verbose_nol " * Kernel has set the spec_ctrl flag in cpuinfo: "
|
|
if [ "$opt_live" = 1 ]; then
|
|
if grep ^flags /proc/cpuinfo | grep -qw spec_ctrl; then
|
|
pstatus green YES
|
|
else
|
|
pstatus blue NO
|
|
fi
|
|
else
|
|
pstatus blue N/A "not testable in offline mode"
|
|
fi
|
|
fi
|
|
|
|
# IBPB
|
|
_info " * Indirect Branch Prediction Barrier (IBPB)"
|
|
_info_nol " * PRED_CMD MSR is available: "
|
|
if [ ! -e /dev/cpu/0/msr ]; then
|
|
pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/msr, is msr support enabled in your kernel?"
|
|
else
|
|
# the new MSR 'PRED_CTRL' is at offset 0x49, write-only
|
|
# here we use dd, it's the same as using 'wrmsr 0x49 0' but without needing the wrmsr tool
|
|
# if we get a write error, the MSR is not there
|
|
$echo_cmd -ne "\0\0\0\0\0\0\0\0" | dd of=/dev/cpu/0/msr bs=8 count=1 seek=73 oflag=seek_bytes 2>/dev/null; ret=$?
|
|
if [ $ret -eq 0 ]; then
|
|
pstatus green YES
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
|
|
_info_nol " * CPU indicates IBPB capability: "
|
|
if [ ! -e /dev/cpu/0/cpuid ]; then
|
|
pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/cpuid, is cpuid support enabled in your kernel?"
|
|
else
|
|
# CPUID EAX=0x80000008, ECX=0x00 return EBX[12] indicates support for just IBPB.
|
|
if [ "$opt_verbose" -ge 3 ]; then
|
|
dd if=/dev/cpu/0/cpuid bs=16 skip=2147483656 iflag=skip_bytes count=1 >/dev/null 2>/dev/null
|
|
_debug "cpuid: reading leaf80000008 of cpuid on cpu0, ret=$?"
|
|
_debug "cpuid: leaf80000008 eax-ebx-ecx-edx: $(dd if=/dev/cpu/0/cpuid bs=16 skip=2147483656 iflag=skip_bytes count=1 2>/dev/null | od -x -A n)"
|
|
_debug "cpuid: leaf80000008 ebx 3rd byte is: $(dd if=/dev/cpu/0/cpuid bs=16 skip=2147483656 iflag=skip_bytes count=1 2>/dev/null | dd bs=1 skip=5 count=1 2>/dev/null | od -x -A n)"
|
|
fi
|
|
# getting high byte of edx on leaf7 of cpuinfo in decimal
|
|
ebx_b3=$(dd if=/dev/cpu/0/cpuid bs=16 skip=2147483656 iflag=skip_bytes count=1 2>/dev/null | dd bs=1 skip=5 count=1 2>/dev/null | od -t u -A n | awk '{print $1}')
|
|
_debug "cpuid: leaf80000008 ebx 3rd byte: $ebx_b3 (decimal)"
|
|
ebx_bit12=$(( ebx_b3 & 16 ))
|
|
_debug "cpuid: ebx_bit12=$ebx_bit12"
|
|
if [ "$ebx_bit12" -eq 16 ]; then
|
|
pstatus green YES "IBPB_SUPPORT feature bit"
|
|
elif [ "$cpuid_spec_ctrl" = 1 ]; then
|
|
pstatus green YES "SPEC_CTRL feature bit"
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
|
|
# STIBP
|
|
_info " * Single Thread Indirect Branch Predictors (STIBP)"
|
|
_info_nol " * SPEC_CTRL MSR is available: "
|
|
if [ "$spec_ctrl_msr" = 1 ]; then
|
|
pstatus green YES
|
|
elif [ "$spec_ctrl_msr" = 0 ]; then
|
|
pstatus red NO
|
|
else
|
|
pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/msr, is msr support enabled in your kernel?"
|
|
fi
|
|
|
|
_info_nol " * CPU indicates STIBP capability: "
|
|
if [ ! -e /dev/cpu/0/cpuid ]; then
|
|
pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/cpuid, is cpuid support enabled in your kernel?"
|
|
else
|
|
# A processor supports STIBP if it enumerates CPUID (EAX=7H,ECX=0):EDX[27] as 1
|
|
if [ "$opt_verbose" -ge 3 ]; then
|
|
dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 >/dev/null 2>/dev/null
|
|
_debug "cpuid: reading leaf7 of cpuid on cpu0, ret=$?"
|
|
_debug "cpuid: leaf7 eax-ebx-ecx-edx: $(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | od -x -A n)"
|
|
_debug "cpuid: leaf7 edx higher byte is: $(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | dd bs=1 skip=15 count=1 2>/dev/null | od -x -A n)"
|
|
fi
|
|
# getting high byte of edx on leaf7 of cpuinfo in decimal
|
|
edx_hb=$(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | dd bs=1 skip=15 count=1 2>/dev/null | od -t u -A n | awk '{print $1}')
|
|
_debug "cpuid: leaf7 edx higher byte: $edx_hb (decimal)"
|
|
edx_bit27=$(( edx_hb & 8 ))
|
|
_debug "cpuid: edx_bit27=$edx_bit27"
|
|
if [ "$edx_bit27" -eq 8 ]; then
|
|
pstatus green YES
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
|
|
_info " * Enhanced IBRS (IBRS_ALL)"
|
|
_info_nol " * CPU indicates ARCH_CAPABILITIES MSR availability: "
|
|
cpuid_arch_capabilities=-1
|
|
if [ ! -e /dev/cpu/0/cpuid ]; then
|
|
pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/cpuid, is cpuid support enabled in your kernel?"
|
|
else
|
|
# A processor supports STIBP if it enumerates CPUID (EAX=7H,ECX=0):EDX[27] as 1
|
|
if [ "$opt_verbose" -ge 3 ]; then
|
|
dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 >/dev/null 2>/dev/null
|
|
_debug "cpuid: reading leaf7 of cpuid on cpu0, ret=$?"
|
|
_debug "cpuid: leaf7 eax-ebx-ecx-edx: $(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | od -x -A n)"
|
|
_debug "cpuid: leaf7 edx higher byte is: $(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | dd bs=1 skip=15 count=1 2>/dev/null | od -x -A n)"
|
|
fi
|
|
# getting high byte of edx on leaf7 of cpuinfo in decimal
|
|
edx_hb=$(dd if=/dev/cpu/0/cpuid bs=16 skip=7 iflag=skip_bytes count=1 2>/dev/null | dd bs=1 skip=15 count=1 2>/dev/null | od -t u -A n | awk '{print $1}')
|
|
_debug "cpuid: leaf7 edx higher byte: $edx_hb (decimal)"
|
|
edx_bit29=$(( edx_hb & 32 ))
|
|
_debug "cpuid: edx_bit29=$edx_bit29"
|
|
if [ "$edx_bit27" -eq 32 ]; then
|
|
pstatus green YES
|
|
cpuid_arch_capabilities=1
|
|
else
|
|
pstatus red NO
|
|
cpuid_arch_capabilities=0
|
|
fi
|
|
fi
|
|
|
|
_info_nol " * ARCH_CAPABILITIES MSR advertises IBRS_ALL capability: "
|
|
capabilities_rdcl_no=-1
|
|
capabilities_ibrs_all=-1
|
|
if [ "$cpuid_arch_capabilities" = -1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
elif [ "$cpuid_arch_capabilities" != 1 ]; then
|
|
capabilities_rdcl_no=0
|
|
capabilities_ibrs_all=0
|
|
pstatus red NO
|
|
elif [ ! -e /dev/cpu/0/msr ]; then
|
|
spec_ctrl_msr=-1
|
|
pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/msr, is msr support enabled in your kernel?"
|
|
else
|
|
# the new MSR 'ARCH_CAPABILITIES' is at offset 0x10a
|
|
# here we use dd, it's the same as using 'rdmsr 0x10a' but without needing the rdmsr tool
|
|
# if we get a read error, the MSR is not there. bs has to be 8 for msr
|
|
capabilities=$(dd if=/dev/cpu/0/msr bs=8 count=1 skip=266 iflag=skip_bytes 2>/dev/null | od -t u1 -A n | awk '{print $8}'); ret=$?
|
|
capabilities_rdcl_no=0
|
|
capabilities_ibrs_all=0
|
|
if [ $ret -eq 0 ]; then
|
|
_debug "capabilities MSR lower byte is $capabilities (decimal)"
|
|
[ $(( capabilities & 1 )) -eq 1 ] && capabilities_rdcl_no=1
|
|
[ $(( capabilities & 2 )) -eq 2 ] && capabilities_ibrs_all=1
|
|
_debug "capabilities says rdcl_no=$capabilities_rdcl_no ibrs_all=$capabilities_ibrs_all"
|
|
if [ "$capabilities_ibrs_all" = 1 ]; then
|
|
pstatus green YES
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
else
|
|
pstatus yellow UNKNOWN
|
|
fi
|
|
fi
|
|
|
|
_info_nol " * CPU explicitly indicates not being vulnerable to Meltdown (RDCL_NO): "
|
|
if [ "$capabilities_rdcl_no" = -1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
elif [ "$capabilities_rdcl_no" = 1 ]; then
|
|
pstatus green YES
|
|
else
|
|
pstatus blue NO
|
|
fi
|
|
|
|
_info_nol " * CPU microcode is known to cause stability problems: "
|
|
if is_ucode_blacklisted; then
|
|
pstatus red YES "$bad_ucode_found"
|
|
_warn
|
|
_warn "The microcode your CPU is running on is known to cause instability problems,"
|
|
_warn "such as intempestive reboots or random crashes."
|
|
_warn "You are advised to either revert to a previous microcode version (that might not have"
|
|
_warn "the mitigations for Spectre), or upgrade to a newer one if available."
|
|
_warn
|
|
else
|
|
pstatus green NO
|
|
fi
|
|
|
|
_info "* CPU vulnerability to the three speculative execution attacks variants"
|
|
for v in 1 2 3; do
|
|
_info_nol " * Vulnerable to Variant $v: "
|
|
if is_cpu_vulnerable $v; then
|
|
pstatus red YES
|
|
else
|
|
pstatus green NO
|
|
fi
|
|
done
|
|
|
|
_info
|
|
}
|
|
|
|
###################
|
|
# SPECTRE VARIANT 1
|
|
check_variant1()
|
|
{
|
|
_info "\033[1;34mCVE-2017-5753 [bounds check bypass] aka 'Spectre Variant 1'\033[0m"
|
|
|
|
status=UNK
|
|
sys_interface_available=0
|
|
msg=''
|
|
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/spectre_v1"; then
|
|
# this kernel has the /sys interface, trust it over everything
|
|
# v0.33+: don't. some kernels have backported the array_index_mask_nospec() workaround without
|
|
# modifying the vulnerabilities/spectre_v1 file. that's bad. we can't trust it when it says Vulnerable :(
|
|
# see "silent backport" detection at the bottom of this func
|
|
sys_interface_available=1
|
|
fi
|
|
if [ "$opt_sysfs_only" != 1 ]; then
|
|
# no /sys interface (or offline mode), fallback to our own ways
|
|
_info_nol "* Kernel has array_index_mask_nospec: "
|
|
# vanilla: look for the Linus' mask aka array_index_mask_nospec()
|
|
# that is inlined at least in raw_copy_from_user (__get_user_X symbols)
|
|
#mov PER_CPU_VAR(current_task), %_ASM_DX
|
|
#cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX
|
|
#jae bad_get_user
|
|
# /* array_index_mask_nospec() are the 2 opcodes that follow */
|
|
#+sbb %_ASM_DX, %_ASM_DX
|
|
#+and %_ASM_DX, %_ASM_AX
|
|
#ASM_STAC
|
|
# x86 64bits: jae(0x0f 0x83 0x?? 0x?? 0x?? 0x??) sbb(0x48 0x19 0xd2) and(0x48 0x21 0xd0)
|
|
# x86 32bits: cmp(0x3b 0x82 0x?? 0x?? 0x00 0x00) jae(0x73 0x??) sbb(0x19 0xd2) and(0x21 0xd0)
|
|
if [ -n "$vmlinux_err" ]; then
|
|
pstatus yellow UNKNOWN "couldn't check ($vmlinux_err)"
|
|
elif ! which perl >/dev/null 2>&1; then
|
|
pstatus yellow UNKNOWN "missing 'perl' binary, please install it"
|
|
else
|
|
perl -ne '/\x0f\x83....\x48\x19\xd2\x48\x21\xd0/ and $found++; END { exit($found) }' "$vmlinux"; ret=$?
|
|
if [ $ret -gt 0 ]; then
|
|
pstatus green YES "$ret occurence(s) found of 64 bits array_index_mask_nospec()"
|
|
v1_mask_nospec=1
|
|
else
|
|
perl -ne '/\x3b\x82..\x00\x00\x73.\x19\xd2\x21\xd0/ and $found++; END { exit($found) }' "$vmlinux"; ret=$?
|
|
if [ $ret -gt 0 ]; then
|
|
pstatus green YES "$ret occurence(s) found of 32 bits array_index_mask_nospec()"
|
|
v1_mask_nospec=1
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
fi
|
|
|
|
if [ "$opt_verbose" -ge 2 ] || [ "$v1_mask_nospec" != 1 ]; then
|
|
# this is a slow heuristic and we don't need it if we already know the kernel is patched
|
|
# but still show it in verbose mode
|
|
_info_nol "* Checking count of LFENCE opcodes in kernel: "
|
|
if [ -n "$vmlinux_err" ]; then
|
|
pstatus yellow UNKNOWN "couldn't check ($vmlinux_err)"
|
|
else
|
|
if ! which objdump >/dev/null 2>&1; then
|
|
pstatus yellow UNKNOWN "missing 'objdump' tool, please install it, usually it's in the binutils package"
|
|
else
|
|
# here we disassemble the kernel and count the number of occurrences of the LFENCE opcode
|
|
# in non-patched kernels, this has been empirically determined as being around 40-50
|
|
# in patched kernels, this is more around 70-80, sometimes way higher (100+)
|
|
# v0.13: 68 found in a 3.10.23-xxxx-std-ipv6-64 (with lots of modules compiled-in directly), which doesn't have the LFENCE patches,
|
|
# so let's push the threshold to 70.
|
|
nb_lfence=$(objdump -d "$vmlinux" | grep -wc 'lfence')
|
|
if [ "$nb_lfence" -lt 70 ]; then
|
|
pstatus red NO "only $nb_lfence opcodes found, should be >= 70, heuristic to be improved when official patches become available"
|
|
else
|
|
v1_lfence=1
|
|
pstatus green YES "$nb_lfence opcodes found, which is >= 70, heuristic to be improved when official patches become available"
|
|
fi
|
|
fi
|
|
fi
|
|
fi
|
|
|
|
else
|
|
# we have no sysfs but were asked to use it only!
|
|
msg="/sys vulnerability interface use forced, but it's not available!"
|
|
status=UNK
|
|
fi
|
|
|
|
# report status
|
|
cve='CVE-2017-5753'
|
|
if ! is_cpu_vulnerable 1; then
|
|
# override status & msg in case CPU is not vulnerable after all
|
|
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
|
|
elif [ -z "$msg" ]; then
|
|
# if msg is empty, sysfs check didn't fill it, rely on our own test
|
|
if [ "$v1_mask_nospec" = 1 ]; then
|
|
pvulnstatus $cve OK "Kernel source has been patched to mitigate the vulnerability (array_index_mask_nospec)"
|
|
elif [ "$v1_lfence" = 1 ]; then
|
|
pvulnstatus $cve OK "Kernel source has PROBABLY been patched to mitigate the vulnerability (LFENCE opcodes heuristic)"
|
|
elif [ "$vmlinux_err" ]; then
|
|
pvulnstatus $cve UNK "Couldn't find kernel image or tools missing to execute the checks"
|
|
else
|
|
pvulnstatus $cve VULN "Kernel source needs to be patched to mitigate the vulnerability"
|
|
fi
|
|
else
|
|
if [ "$msg" = "Vulnerable" ] && [ "$v1_mask_nospec" = 1 ]; then
|
|
pvulnstatus $cve OK "Kernel source has been patched to mitigate the vulnerability (silent backport of array_index_mask_nospec)"
|
|
else
|
|
[ "$msg" = "Vulnerable" ] && msg="Kernel source needs to be patched to mitigate the vulnerability"
|
|
pvulnstatus $cve "$status" "$msg"
|
|
fi
|
|
fi
|
|
}
|
|
|
|
###################
|
|
# SPECTRE VARIANT 2
|
|
check_variant2()
|
|
{
|
|
_info "\033[1;34mCVE-2017-5715 [branch target injection] aka 'Spectre Variant 2'\033[0m"
|
|
|
|
status=UNK
|
|
sys_interface_available=0
|
|
msg=''
|
|
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/spectre_v2"; then
|
|
# this kernel has the /sys interface, trust it over everything
|
|
sys_interface_available=1
|
|
fi
|
|
if [ "$opt_sysfs_only" != 1 ]; then
|
|
_info "* Mitigation 1"
|
|
_info_nol " * Kernel is compiled with IBRS/IBPB support: "
|
|
ibrs_can_tell=0
|
|
|
|
if [ "$opt_live" = 1 ]; then
|
|
ibrs_can_tell=1
|
|
mount_debugfs
|
|
for dir in \
|
|
/sys/kernel/debug \
|
|
/sys/kernel/debug/x86 \
|
|
/proc/sys/kernel; do
|
|
if [ -e "$dir/ibrs_enabled" ]; then
|
|
# if the file is there, we have IBRS compiled-in
|
|
# /sys/kernel/debug/ibrs_enabled: vanilla
|
|
# /sys/kernel/debug/x86/ibrs_enabled: RedHat (see https://access.redhat.com/articles/3311301)
|
|
# /proc/sys/kernel/ibrs_enabled: OpenSUSE tumbleweed
|
|
pstatus green YES
|
|
ibrs_knob_dir=$dir
|
|
ibrs_supported=1
|
|
ibrs_enabled=$(cat "$dir/ibrs_enabled" 2>/dev/null)
|
|
_debug "ibrs: found $dir/ibrs_enabled=$ibrs_enabled"
|
|
if [ -e "$dir/ibpb_enabled" ]; then
|
|
ibpb_enabled=$(cat "$dir/ibpb_enabled" 2>/dev/null)
|
|
_debug "ibpb: found $dir/ibpb_enabled=$ibpb_enabled"
|
|
else
|
|
ibpb_enabled=-1
|
|
_debug "ibpb: no ibpb_enabled file in $dir"
|
|
fi
|
|
break
|
|
else
|
|
_debug "ibrs: $dir/ibrs_enabled file doesn't exist"
|
|
fi
|
|
done
|
|
# on some newer kernels, the spec_ctrl_ibrs flag in /proc/cpuinfo
|
|
# is set when ibrs has been administratively enabled (usually from cmdline)
|
|
# which in that case means ibrs is supported *and* enabled for kernel & user
|
|
# as per the ibrs patch series v3
|
|
if [ "$ibrs_supported" = 0 ]; then
|
|
if grep ^flags /proc/cpuinfo | grep -qw spec_ctrl_ibrs; then
|
|
_debug "ibrs: found spec_ctrl_ibrs flag in /proc/cpuinfo"
|
|
ibrs_supported=1
|
|
# enabled=2 -> kernel & user
|
|
ibrs_enabled=2
|
|
# XXX and what about ibpb ?
|
|
fi
|
|
fi
|
|
fi
|
|
if [ "$ibrs_supported" != 1 ] && [ -n "$opt_map" ]; then
|
|
ibrs_can_tell=1
|
|
if grep -q spec_ctrl "$opt_map"; then
|
|
pstatus green YES
|
|
ibrs_supported=1
|
|
_debug "ibrs: found '*spec_ctrl*' symbol in $opt_map"
|
|
fi
|
|
fi
|
|
if [ "$ibrs_supported" != 1 ]; then
|
|
if [ "$ibrs_can_tell" = 1 ]; then
|
|
pstatus red NO
|
|
else
|
|
# if we're in offline mode without System.map, we can't really know
|
|
pstatus yellow UNKNOWN "in offline mode, we need System.map to be able to tell"
|
|
fi
|
|
fi
|
|
|
|
_info " * Currently enabled features"
|
|
_info_nol " * IBRS enabled for Kernel space: "
|
|
if [ "$opt_live" = 1 ]; then
|
|
if [ "$ibpb_enabled" = 2 ]; then
|
|
# if ibpb=2, ibrs is forcefully=0
|
|
pstatus blue NO "IBPB used instead of IBRS in all kernel entrypoints"
|
|
else
|
|
# 0 means disabled
|
|
# 1 is enabled only for kernel space
|
|
# 2 is enabled for kernel and user space
|
|
case "$ibrs_enabled" in
|
|
"")
|
|
if [ "$ibrs_supported" = 1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
;;
|
|
0)
|
|
pstatus red NO
|
|
if [ "$opt_verbose" -ge 2 ]; then
|
|
_info " - To enable, \`echo 1 > $ibrs_knob_dir/ibrs_enabled' as root. If you don't have hardware support, you'll get an error."
|
|
fi
|
|
;;
|
|
1 | 2) pstatus green YES;;
|
|
*) pstatus yellow UNKNOWN;;
|
|
esac
|
|
fi
|
|
else
|
|
pstatus blue N/A "not testable in offline mode"
|
|
fi
|
|
|
|
_info_nol " * IBRS enabled for User space: "
|
|
if [ "$opt_live" = 1 ]; then
|
|
if [ "$ibpb_enabled" = 2 ]; then
|
|
# if ibpb=2, ibrs is forcefully=0
|
|
pstatus blue NO "IBPB used instead of IBRS in all kernel entrypoints"
|
|
else
|
|
case "$ibrs_enabled" in
|
|
"")
|
|
if [ "$ibrs_supported" = 1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
;;
|
|
0 | 1)
|
|
pstatus red NO
|
|
if [ "$opt_verbose" -ge 2 ]; then
|
|
_info " - To enable, \`echo 2 > $ibrs_knob_dir/ibrs_enabled' as root. If you don't have hardware support, you'll get an error."
|
|
fi
|
|
;;
|
|
2) pstatus green YES;;
|
|
*) pstatus yellow UNKNOWN;;
|
|
esac
|
|
fi
|
|
else
|
|
pstatus blue N/A "not testable in offline mode"
|
|
fi
|
|
|
|
_info_nol " * IBPB enabled: "
|
|
if [ "$opt_live" = 1 ]; then
|
|
case "$ibpb_enabled" in
|
|
"")
|
|
if [ "$ibrs_supported" = 1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
;;
|
|
0)
|
|
pstatus red NO
|
|
if [ "$opt_verbose" -ge 2 ]; then
|
|
_info " - To enable, \`echo 1 > $ibrs_knob_dir/ibpb_enabled' as root. If you don't have hardware support, you'll get an error."
|
|
fi
|
|
;;
|
|
1) pstatus green YES;;
|
|
2) pstatus green YES "IBPB used instead of IBRS in all kernel entrypoints";;
|
|
*) pstatus yellow UNKNOWN;;
|
|
esac
|
|
else
|
|
pstatus blue N/A "not testable in offline mode"
|
|
fi
|
|
|
|
unload_msr
|
|
unload_cpuid
|
|
|
|
_info "* Mitigation 2"
|
|
_info_nol " * Kernel compiled with retpoline option: "
|
|
# We check the RETPOLINE kernel options
|
|
if [ -r "$opt_config" ]; then
|
|
if grep -q '^CONFIG_RETPOLINE=y' "$opt_config"; then
|
|
pstatus green YES
|
|
retpoline=1
|
|
# shellcheck disable=SC2046
|
|
_debug 'retpoline: found '$(grep '^CONFIG_RETPOLINE' "$opt_config")" in $opt_config"
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
else
|
|
pstatus yellow UNKNOWN "couldn't read your kernel configuration"
|
|
fi
|
|
|
|
_info_nol " * Kernel compiled with a retpoline-aware compiler: "
|
|
# Now check if the compiler used to compile the kernel knows how to insert retpolines in generated asm
|
|
# For gcc, this is -mindirect-branch=thunk-extern (detected by the kernel makefiles)
|
|
# See gcc commit https://github.com/hjl-tools/gcc/commit/23b517d4a67c02d3ef80b6109218f2aadad7bd79
|
|
# In latest retpoline LKML patches, the noretpoline_setup symbol exists only if CONFIG_RETPOLINE is set
|
|
# *AND* if the compiler is retpoline-compliant, so look for that symbol
|
|
if [ -e "/sys/devices/system/cpu/vulnerabilities/spectre_v2" ]; then
|
|
if grep -qw Minimal /sys/devices/system/cpu/vulnerabilities/spectre_v2; then
|
|
pstatus red NO "kernel reports minimal retpoline compilation"
|
|
elif grep -qw Full /sys/devices/system/cpu/vulnerabilities/spectre_v2; then
|
|
retpoline_compiler=1
|
|
pstatus green YES "kernel reports full retpoline compilation"
|
|
else
|
|
if [ "$retpoline" = 1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
elif [ -n "$opt_map" ]; then
|
|
# look for the symbol
|
|
if grep -qw noretpoline_setup "$opt_map"; then
|
|
retpoline_compiler=1
|
|
pstatus green YES "noretpoline_setup symbol found in System.map"
|
|
else
|
|
if [ "$retpoline" = 1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
elif [ -n "$vmlinux" ]; then
|
|
# look for the symbol
|
|
if which nm >/dev/null 2>&1; then
|
|
# the proper way: use nm and look for the symbol
|
|
if nm "$vmlinux" 2>/dev/null | grep -qw 'noretpoline_setup'; then
|
|
retpoline_compiler=1
|
|
pstatus green YES "noretpoline_setup found in vmlinux symbols"
|
|
else
|
|
if [ "$retpoline" = 1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
elif grep -q noretpoline_setup "$vmlinux"; then
|
|
# if we don't have nm, nevermind, the symbol name is long enough to not have
|
|
# any false positive using good old grep directly on the binary
|
|
retpoline_compiler=1
|
|
pstatus green YES "noretpoline_setup found in vmlinux"
|
|
else
|
|
if [ "$retpoline" = 1 ]; then
|
|
pstatus yellow UNKNOWN
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
else
|
|
if [ "$retpoline" = 1 ]; then
|
|
pstatus yellow UNKNOWN "couldn't find your kernel image or System.map"
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
fi
|
|
|
|
_info_nol " * Retpoline enabled: "
|
|
if [ "$opt_live" = 1 ]; then
|
|
# kernel adds this flag when retpoline is supported and enabled,
|
|
# regardless of the fact that it's minimal / full and generic / amd
|
|
if grep -qw retpoline /proc/cpuinfo; then
|
|
pstatus green YES
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
else
|
|
pstatus blue N/A "can't check this in offline mode"
|
|
fi
|
|
elif [ "$sys_interface_available" = 0 ]; then
|
|
# we have no sysfs but were asked to use it only!
|
|
msg="/sys vulnerability interface use forced, but it's not available!"
|
|
status=UNK
|
|
fi
|
|
|
|
cve='CVE-2017-5715'
|
|
if ! is_cpu_vulnerable 2; then
|
|
# override status & msg in case CPU is not vulnerable after all
|
|
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
|
|
elif [ -z "$msg" ]; then
|
|
# if msg is empty, sysfs check didn't fill it, rely on our own test
|
|
if [ "$retpoline" = 1 ] && [ "$retpoline_compiler" = 1 ]; then
|
|
pvulnstatus $cve OK "retpoline mitigates the vulnerability"
|
|
elif [ "$opt_live" = 1 ]; then
|
|
if ( [ "$ibrs_enabled" = 1 ] || [ "$ibrs_enabled" = 2 ] ) && [ "$ibpb_enabled" = 1 ]; then
|
|
pvulnstatus $cve OK "IBRS/IBPB are mitigating the vulnerability"
|
|
elif ( [ "$ibrs_enabled" = 1 ] || [ "$ibrs_enabled" = 2 ] ) && [ "$ibpb_enabled" = -1 ]; then
|
|
# IBPB doesn't seem here on this kernel
|
|
pvulnstatus $cve OK "IBRS is mitigating the vulnerability"
|
|
elif [ "$ibpb_enabled" = 2 ]; then
|
|
pvulnstatus $cve OK "Full IBPB is mitigating the vulnerability"
|
|
else
|
|
pvulnstatus $cve VULN "IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
|
|
fi
|
|
else
|
|
if [ "$ibrs_supported" = 1 ]; then
|
|
pvulnstatus $cve OK "offline mode: IBRS/IBPB will mitigate the vulnerability if enabled at runtime"
|
|
elif [ "$ibrs_can_tell" = 1 ]; then
|
|
pvulnstatus $cve VULN "IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
|
|
else
|
|
pvulnstatus $cve UNK "offline mode: not enough information"
|
|
fi
|
|
fi
|
|
else
|
|
[ "$msg" = "Vulnerable" ] && msg="IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
|
|
pvulnstatus $cve "$status" "$msg"
|
|
fi
|
|
}
|
|
|
|
########################
|
|
# MELTDOWN aka VARIANT 3
|
|
check_variant3()
|
|
{
|
|
_info "\033[1;34mCVE-2017-5754 [rogue data cache load] aka 'Meltdown' aka 'Variant 3'\033[0m"
|
|
|
|
status=UNK
|
|
sys_interface_available=0
|
|
msg=''
|
|
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/meltdown"; then
|
|
# this kernel has the /sys interface, trust it over everything
|
|
sys_interface_available=1
|
|
fi
|
|
if [ "$opt_sysfs_only" != 1 ]; then
|
|
_info_nol "* Kernel supports Page Table Isolation (PTI): "
|
|
kpti_support=0
|
|
kpti_can_tell=0
|
|
if [ -n "$opt_config" ]; then
|
|
kpti_can_tell=1
|
|
if grep -Eq '^(CONFIG_PAGE_TABLE_ISOLATION|CONFIG_KAISER)=y' "$opt_config"; then
|
|
# shellcheck disable=SC2046
|
|
_debug 'kpti_support: found option '$(grep -E '^(CONFIG_PAGE_TABLE_ISOLATION|CONFIG_KAISER)=y' "$opt_config")" in $opt_config"
|
|
kpti_support=1
|
|
fi
|
|
fi
|
|
if [ "$kpti_support" = 0 ] && [ -n "$opt_map" ]; then
|
|
# it's not an elif: some backports don't have the PTI config but still include the patch
|
|
# so we try to find an exported symbol that is part of the PTI patch in System.map
|
|
kpti_can_tell=1
|
|
if grep -qw kpti_force_enabled "$opt_map"; then
|
|
_debug "kpti_support: found kpti_force_enabled in $opt_map"
|
|
kpti_support=1
|
|
fi
|
|
fi
|
|
if [ "$kpti_support" = 0 ] && [ -n "$vmlinux" ]; then
|
|
# same as above but in case we don't have System.map and only vmlinux, look for the
|
|
# nopti option that is part of the patch (kernel command line option)
|
|
kpti_can_tell=1
|
|
if ! which strings >/dev/null 2>&1; then
|
|
pstatus yellow UNKNOWN "missing 'strings' tool, please install it, usually it's in the binutils package"
|
|
else
|
|
if strings "$vmlinux" | grep -qw nopti; then
|
|
_debug "kpti_support: found nopti string in $vmlinux"
|
|
kpti_support=1
|
|
fi
|
|
fi
|
|
fi
|
|
|
|
if [ "$kpti_support" = 1 ]; then
|
|
pstatus green YES
|
|
elif [ "$kpti_can_tell" = 1 ]; then
|
|
pstatus red NO
|
|
else
|
|
pstatus yellow UNKNOWN "couldn't read your kernel configuration nor System.map file"
|
|
fi
|
|
|
|
mount_debugfs
|
|
_info_nol "* PTI enabled and active: "
|
|
if [ "$opt_live" = 1 ]; then
|
|
dmesg_grep="Kernel/User page tables isolation: enabled"
|
|
dmesg_grep="$dmesg_grep|Kernel page table isolation enabled"
|
|
dmesg_grep="$dmesg_grep|x86/pti: Unmapping kernel while in userspace"
|
|
if grep ^flags /proc/cpuinfo | grep -qw pti; then
|
|
# vanilla PTI patch sets the 'pti' flag in cpuinfo
|
|
_debug "kpti_enabled: found 'pti' flag in /proc/cpuinfo"
|
|
kpti_enabled=1
|
|
elif grep ^flags /proc/cpuinfo | grep -qw kaiser; then
|
|
# kernel line 4.9 sets the 'kaiser' flag in cpuinfo
|
|
_debug "kpti_enabled: found 'kaiser' flag in /proc/cpuinfo"
|
|
kpti_enabled=1
|
|
elif [ -e /sys/kernel/debug/x86/pti_enabled ]; then
|
|
# RedHat Backport creates a dedicated file, see https://access.redhat.com/articles/3311301
|
|
kpti_enabled=$(cat /sys/kernel/debug/x86/pti_enabled 2>/dev/null)
|
|
_debug "kpti_enabled: file /sys/kernel/debug/x86/pti_enabled exists and says: $kpti_enabled"
|
|
fi
|
|
if [ -z "$kpti_enabled" ]; then
|
|
dmesg_grep "$dmesg_grep"; ret=$?
|
|
if [ $ret -eq 0 ]; then
|
|
_debug "kpti_enabled: found hint in dmesg: $dmesg_grepped"
|
|
kpti_enabled=1
|
|
elif [ $ret -eq 2 ]; then
|
|
_debug "kpti_enabled: dmesg truncated"
|
|
kpti_enabled=-1
|
|
fi
|
|
fi
|
|
if [ -z "$kpti_enabled" ]; then
|
|
_debug "kpti_enabled: couldn't find any hint that PTI is enabled"
|
|
kpti_enabled=0
|
|
fi
|
|
if [ "$kpti_enabled" = 1 ]; then
|
|
pstatus green YES
|
|
elif [ "$kpti_enabled" = -1 ]; then
|
|
pstatus yellow UNKNOWN "dmesg truncated, please reboot and relaunch this script"
|
|
else
|
|
pstatus red NO
|
|
fi
|
|
else
|
|
pstatus blue N/A "can't verify if PTI is enabled in offline mode"
|
|
fi
|
|
|
|
# no security impact but give a hint to the user in verbose mode
|
|
# about PCID/INVPCID cpuid features that must be present to avoid
|
|
# too big a performance impact with PTI
|
|
# refs:
|
|
# https://marc.info/?t=151532047900001&r=1&w=2
|
|
# https://groups.google.com/forum/m/#!topic/mechanical-sympathy/L9mHTbeQLNU
|
|
if [ "$opt_verbose" -ge 2 ]; then
|
|
_info "* Performance impact if PTI is enabled"
|
|
_info_nol " * CPU supports PCID: "
|
|
if grep ^flags /proc/cpuinfo | grep -qw pcid; then
|
|
pstatus green YES 'performance degradation with PTI will be limited'
|
|
else
|
|
pstatus blue NO 'no security impact but performance will be degraded with PTI'
|
|
fi
|
|
_info_nol " * CPU supports INVPCID: "
|
|
if grep ^flags /proc/cpuinfo | grep -qw invpcid; then
|
|
pstatus green YES 'performance degradation with PTI will be limited'
|
|
else
|
|
pstatus blue NO 'no security impact but performance will be degraded with PTI'
|
|
fi
|
|
fi
|
|
elif [ "$sys_interface_available" = 0 ]; then
|
|
# we have no sysfs but were asked to use it only!
|
|
msg="/sys vulnerability interface use forced, but it's not available!"
|
|
status=UNK
|
|
fi
|
|
|
|
|
|
# Test if the current host is a Xen PV Dom0 / DomU
|
|
if [ -d "/proc/xen" ]; then
|
|
# XXX do we have a better way that relying on dmesg?
|
|
dmesg_grep 'Booting paravirtualized kernel on Xen$'; ret=$?
|
|
if [ $ret -eq 2 ]; then
|
|
_warn "dmesg truncated, Xen detection will be unreliable. Please reboot and relaunch this script"
|
|
elif [ $ret -eq 0 ]; then
|
|
if [ -e /proc/xen/capabilities ] && grep -q "control_d" /proc/xen/capabilities; then
|
|
xen_pv_domo=1
|
|
else
|
|
xen_pv_domu=1
|
|
fi
|
|
fi
|
|
fi
|
|
|
|
if [ "$opt_live" = 1 ]; then
|
|
# checking whether we're running under Xen PV 64 bits. If yes, we are affected by variant3
|
|
# (unless we are a Dom0)
|
|
_info_nol "* Running as a Xen PV DomU: "
|
|
if [ "$xen_pv_domu" = 1 ]; then
|
|
pstatus red YES
|
|
else
|
|
pstatus green NO
|
|
fi
|
|
fi
|
|
|
|
cve='CVE-2017-5754'
|
|
if ! is_cpu_vulnerable 3; then
|
|
# override status & msg in case CPU is not vulnerable after all
|
|
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
|
|
elif [ -z "$msg" ]; then
|
|
# if msg is empty, sysfs check didn't fill it, rely on our own test
|
|
if [ "$opt_live" = 1 ]; then
|
|
if [ "$kpti_enabled" = 1 ]; then
|
|
pvulnstatus $cve OK "PTI mitigates the vulnerability"
|
|
elif [ "$xen_pv_domo" = 1 ]; then
|
|
pvulnstatus $cve OK "Xen Dom0s are safe and do not require PTI"
|
|
elif [ "$xen_pv_domu" = 1 ]; then
|
|
pvulnstatus $cve VULN "Xen PV DomUs are vulnerable and need to be run in HVM, PVHVM or PVH mode"
|
|
else
|
|
pvulnstatus $cve VULN "PTI is needed to mitigate the vulnerability"
|
|
fi
|
|
else
|
|
if [ "$kpti_support" = 1 ]; then
|
|
pvulnstatus $cve OK "offline mode: PTI will mitigate the vulnerability if enabled at runtime"
|
|
elif [ "$kpti_can_tell" = 1 ]; then
|
|
pvulnstatus $cve VULN "PTI is needed to mitigate the vulnerability"
|
|
else
|
|
pvulnstatus $cve UNK "offline mode: not enough information"
|
|
fi
|
|
fi
|
|
else
|
|
if [ "$xen_pv_domo" = 1 ]; then
|
|
msg="Xen Dom0s are safe and do not require PTI"
|
|
status="OK"
|
|
elif [ "$xen_pv_domu" = 1 ]; then
|
|
msg="Xen PV DomUs are vulnerable and need to be run in HVM, PVHVM or PVH mode"
|
|
status="VULN"
|
|
elif [ "$msg" = "Vulnerable" ]; then
|
|
msg="PTI is needed to mitigate the vulnerability"
|
|
fi
|
|
pvulnstatus $cve "$status" "$msg"
|
|
fi
|
|
|
|
# Warn the user about XSA-254 recommended mitigations
|
|
if [ "$xen_pv_domo" = 1 ]; then
|
|
_warn
|
|
_warn "This host is a Xen Dom0. Please make sure that you are running your DomUs"
|
|
_warn "in HVM, PVHVM or PVH mode to prevent any guest-to-host / host-to-guest attacks."
|
|
_warn
|
|
_warn "See https://blog.xenproject.org/2018/01/22/xen-project-spectre-meltdown-faq-jan-22-update/ and XSA-254 for details."
|
|
fi
|
|
}
|
|
|
|
check_cpu
|
|
# now run the checks the user asked for
|
|
if [ "$opt_variant1" = 1 ] || [ "$opt_allvariants" = 1 ]; then
|
|
check_variant1
|
|
_info
|
|
fi
|
|
if [ "$opt_variant2" = 1 ] || [ "$opt_allvariants" = 1 ]; then
|
|
check_variant2
|
|
_info
|
|
fi
|
|
if [ "$opt_variant3" = 1 ] || [ "$opt_allvariants" = 1 ]; then
|
|
check_variant3
|
|
_info
|
|
fi
|
|
|
|
_info "A false sense of security is worse than no security at all, see --disclaimer"
|
|
|
|
# this'll umount only if we mounted debugfs ourselves
|
|
umount_debugfs
|
|
|
|
# cleanup the temp decompressed config
|
|
[ -n "$dumped_config" ] && [ -f "$dumped_config" ] && rm -f "$dumped_config"
|
|
|
|
if [ "$opt_batch" = 1 ] && [ "$opt_batch_format" = "nrpe" ]; then
|
|
if [ ! -z "$nrpe_vuln" ]; then
|
|
echo "Vulnerable:$nrpe_vuln"
|
|
else
|
|
echo "OK"
|
|
fi
|
|
fi
|
|
|
|
if [ "$opt_batch" = 1 ] && [ "$opt_batch_format" = "json" ]; then
|
|
_echo 0 "${json_output%?}]"
|
|
fi
|
|
|
|
# exit with the proper exit code
|
|
[ "$global_critical" = 1 ] && exit 2 # critical
|
|
[ "$global_unknown" = 1 ] && exit 3 # unknown
|
|
exit 0 # ok
|