dsanchez/spectre-meltdown-checker
1
0
Fork 0
mirror of https://github.com/speed47/spectre-meltdown-checker synced 2024-11-07 06:33:38 +01:00
Code Issues Releases Wiki Activity
b44d2b5470
spectre-meltdown-checker/spectre-meltdown-checker.sh
Stéphane Lesimple 7b72c20f89 feat(l1tf): explode L1TF in its 3 distinct CVEs
2018-09-17 21:44:48 +02:00

3741 lines
135 KiB
Bash
Executable File
Raw Blame History

#! /bin/sh
# SPDX-License-Identifier: GPL-3.0
#
# Spectre & Meltdown checker
#
# Check for the latest version at:
# https://github.com/speed47/spectre-meltdown-checker
# git clone https://github.com/speed47/spectre-meltdown-checker.git
# or wget https://meltdown.ovh -O spectre-meltdown-checker.sh
# or curl -L https://meltdown.ovh -o spectre-meltdown-checker.sh
#
# Stephane Lesimple
#
VERSION='0.39+'
trap 'exit_cleanup' EXIT
trap '_warn "interrupted, cleaning up..."; exit_cleanup; exit 1' INT
exit_cleanup()
{
# cleanup the temp decompressed config & kernel image
[ -n "$dumped_config" ] && [ -f "$dumped_config" ] && rm -f "$dumped_config"
[ -n "$kerneltmp" ] && [ -f "$kerneltmp" ] && rm -f "$kerneltmp"
[ -n "$kerneltmp2" ] && [ -f "$kerneltmp2" ] && rm -f "$kerneltmp2"
[ "$mounted_debugfs" = 1 ] && umount /sys/kernel/debug 2>/dev/null
[ "$mounted_procfs" = 1 ] && umount "$procfs" 2>/dev/null
[ "$insmod_cpuid" = 1 ] && rmmod cpuid 2>/dev/null
[ "$insmod_msr" = 1 ] && rmmod msr 2>/dev/null
[ "$kldload_cpuctl" = 1 ] && kldunload cpuctl 2>/dev/null
}
# if we were git clone'd, adjust VERSION
if [ -d "$(dirname "$0")/.git" ] && which git >/dev/null 2>&1; then
describe=$(git -C "$(dirname "$0")" describe --tags --dirty 2>/dev/null)
[ -n "$describe" ] && VERSION=$(echo "$describe" | sed -e s/^v//)
fi
show_usage()
{
# shellcheck disable=SC2086
cat <<EOF
Usage:
Live mode: $(basename $0) [options] [--live]
Offline mode: $(basename $0) [options] [--kernel <kernel_file>] [--config <kernel_config>] [--map <kernel_map_file>]
Modes:
Two modes are available.
First mode is the "live" mode (default), it does its best to find information about the currently running kernel.
To run under this mode, just start the script without any option (you can also use --live explicitly)
Second mode is the "offline" mode, where you can inspect a non-running kernel.
You'll need to specify the location of the kernel file, config and System.map files:
--kernel kernel_file specify a (possibly compressed) Linux or BSD kernel file
--config kernel_config specify a kernel config file (Linux only)
--map kernel_map_file specify a kernel System.map file (Linux only)
Options:
--no-color don't use color codes
--verbose, -v increase verbosity level, possibly several times
--explain produce an additional human-readable explanation of actions to take to mitigate a vulnerability
--paranoid require IBPB to deem Variant 2 as mitigated
also require SMT disabled + unconditional L1D flush to deem Foreshadow-NG VMM as mitigated
--no-sysfs don't use the /sys interface even if present [Linux]
--sysfs-only only use the /sys interface, don't run our own checks [Linux]
--coreos special mode for CoreOS (use an ephemeral toolbox to inspect kernel) [Linux]
--arch-prefix PREFIX specify a prefix for cross-inspecting a kernel of a different arch, for example "aarch64-linux-gnu-",
so that invoked tools will be prefixed with this (i.e. aarch64-linux-gnu-objdump)
--batch text produce machine readable output, this is the default if --batch is specified alone
--batch short produce only one line with the vulnerabilities separated by spaces
--batch json produce JSON output formatted for Puppet, Ansible, Chef...
--batch nrpe produce machine readable output formatted for NRPE
--batch prometheus produce output for consumption by prometheus-node-exporter
--variant [1,2,3,3a,4,l1tf] specify which variant you'd like to check, by default all variants are checked
--cve [cve1,cve2,...] specify which CVE you'd like to check, by default all supported CVEs are checked
can be specified multiple times (e.g. --variant 2 --variant 3)
--hw-only only check for CPU information, don't check for any variant
--no-hw skip CPU information and checks, if you're inspecting a kernel not to be run on this host
--vmm [auto,yes,no] override the detection of the presence of an hypervisor (for CVE-2018-3646), default: auto
Return codes:
0 (not vulnerable), 2 (vulnerable), 3 (unknown), 255 (error)
IMPORTANT:
A false sense of security is worse than no security at all.
Please use the --disclaimer option to understand exactly what this script does.
EOF
}
show_disclaimer()
{
cat <<EOF
Disclaimer:
This tool does its best to determine whether your system is immune (or has proper mitigations in place) for the
collectively named "speculative execution" vulnerabilities. It doesn't attempt to run any kind of exploit, and can't guarantee
that your system is secure, but rather helps you verifying whether your system has the known correct mitigations in place.
However, some mitigations could also exist in your kernel that this script doesn't know (yet) how to detect, or it might
falsely detect mitigations that in the end don't work as expected (for example, on backported or modified kernels).
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
vulnerabilities (except some specific ARM models). All Intel processors manufactured since circa 1995 are thought to be vulnerable,
except some specific/old models, such as some early Atoms. Whatever processor one uses, one might seek more information
from the manufacturer of that processor and/or of the device in which it runs.
The nature of the discovered vulnerabilities being quite new, the landscape of vulnerable processors can be expected
to change over time, which is why this script makes the assumption that all CPUs are vulnerable, except if the manufacturer
explicitly stated otherwise in a verifiable public announcement.
Please also note that for Spectre vulnerabilities, all software can possibly be exploited, this tool only verifies that the
kernel (which is the core of the system) you're using has the proper protections in place. Verifying all the other software
is out of the scope of this tool. As a general measure, ensure you always have the most up to date stable versions of all
the software you use, especially for those who are exposed to the world, such as network daemons and browsers.
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.
EOF
}
os=$(uname -s)
# parse options
opt_kernel=''
opt_config=''
opt_map=''
opt_live_explicit=0
opt_live=1
opt_no_color=0
opt_batch=0
opt_batch_format="text"
opt_verbose=1
opt_cve_list=''
opt_cve_all=1
opt_no_sysfs=0
opt_sysfs_only=0
opt_coreos=0
opt_arch_prefix=''
opt_hw_only=0
opt_no_hw=0
opt_vmm=-1
opt_explain=0
opt_paranoid=0
global_critical=0
global_unknown=0
nrpe_vuln=""
supported_cve_list='CVE-2017-5753 CVE-2017-5715 CVE-2017-5754 CVE-2018-3640 CVE-2018-3639 CVE-2018-3615 CVE-2018-3620 CVE-2018-3646'
# find a sane command to print colored messages, we prefer `printf` over `echo`
# because `printf` behavior is more standard across Linux/BSD
# we'll try to avoid using shell builtins that might not take options
echo_cmd_type=echo
if which printf >/dev/null 2>&1; then
echo_cmd=$(which printf)
echo_cmd_type=printf
elif which echo >/dev/null 2>&1; then
echo_cmd=$(which echo)
else
# maybe the `which` command is broken?
[ -x /bin/echo ] && echo_cmd=/bin/echo
# for Android
[ -x /system/bin/echo ] && echo_cmd=/system/bin/echo
fi
# still empty? fallback to builtin
[ -z "$echo_cmd" ] && echo_cmd=echo
__echo()
{
opt="$1"
shift
_msg="$*"
if [ "$opt_no_color" = 1 ] ; then
# strip ANSI color codes
# some sed versions (i.e. toybox) can't seem to handle
# \033 aka \x1B correctly, so do it for them.
if [ "$echo_cmd_type" = printf ]; then
_interpret_chars=''
else
_interpret_chars='-e'
fi
_ctrlchar=$($echo_cmd $_interpret_chars "\033")
_msg=$($echo_cmd $_interpret_chars "$_msg" | sed -r "s/$_ctrlchar\[([0-9][0-9]?(;[0-9][0-9]?)?)?m//g")
fi
if [ "$echo_cmd_type" = printf ]; then
if [ "$opt" = "-n" ]; then
$echo_cmd "$_msg"
else
$echo_cmd "$_msg\n"
fi
else
# shellcheck disable=SC2086
$echo_cmd $opt -e "$_msg"
fi
}
_echo()
{
if [ "$opt_verbose" -ge "$1" ]; then
shift
__echo '' "$*"
fi
}
_echo_nol()
{
if [ "$opt_verbose" -ge "$1" ]; then
shift
__echo -n "$*"
fi
}
_warn()
{
_echo 0 "\033[31m$*\033[0m" >&2
}
_info()
{
_echo 1 "$*"
}
_info_nol()
{
_echo_nol 1 "$*"
}
_verbose()
{
_echo 2 "$*"
}
_verbose_nol()
{
_echo_nol 2 "$*"
}
_debug()
{
_echo 3 "\033[34m(debug) $*\033[0m"
}
explain()
{
if [ "$opt_explain" = 1 ] ; then
_info ''
_info "> \033[41m\033[30mHow to fix:\033[0m $*"
fi
}
cve2name()
{
case "$1" in
CVE-2017-5753) echo "Spectre Variant 1, bounds check bypass";;
CVE-2017-5715) echo "Spectre Variant 2, branch target injection";;
CVE-2017-5754) echo "Variant 3, Meltdown, rogue data cache load";;
CVE-2018-3640) echo "Variant 3a, rogue system register read";;
CVE-2018-3639) echo "Variant 4, speculative store bypass";;
CVE-2018-3615) echo "Foreshadow (SGX), L1 terminal fault";;
CVE-2018-3620) echo "Foreshadow-NG (OS), L1 terminal fault";;
CVE-2018-3646) echo "Foreshadow-NG (VMM), L1 terminal fault";;
esac
}
is_cpu_vulnerable_cached=0
_is_cpu_vulnerable_cached()
{
# shellcheck disable=SC2086
case "$1" in
CVE-2017-5753) return $variant1;;
CVE-2017-5715) return $variant2;;
CVE-2017-5754) return $variant3;;
CVE-2018-3640) return $variant3a;;
CVE-2018-3639) return $variant4;;
CVE-2018-3615) return $variantl1tf_sgx;;
CVE-2018-3620) return $variantl1tf;;
CVE-2018-3646) return $variantl1tf;;
esac
echo "$0: error: invalid variant '$1' passed to is_cpu_vulnerable()" >&2
exit 255
}
is_cpu_vulnerable()
{
# param: one of the $supported_cve_list items
# returns 0 if vulnerable, 1 if not vulnerable
# (note that in shell, a return of 0 is success)
# by default, everything is vulnerable, we work in a "whitelist" logic here.
# usage: is_cpu_vulnerable CVE-xxxx-yyyy && do something if vulnerable
if [ "$is_cpu_vulnerable_cached" = 1 ]; then
_is_cpu_vulnerable_cached "$1"
return $?
fi
variant1=''
variant2=''
variant3=''
variant3a=''
variant4=''
variantl1tf=''
if is_cpu_specex_free; then
variant1=immune
variant2=immune
variant3=immune
variant3a=immune
variant4=immune
variantl1tf=immune
elif is_intel; then
# Intel
# https://github.com/crozone/SpectrePoC/issues/1 ^F E5200 => spectre 2 not vulnerable
# https://github.com/paboldin/meltdown-exploit/issues/19 ^F E5200 => meltdown vulnerable
# model name : Pentium(R) Dual-Core CPU E5200 @ 2.50GHz
if grep -qE '^model name.+ Pentium\(R\) Dual-Core[[:space:]]+CPU[[:space:]]+E[0-9]{4}K? ' "$procfs/cpuinfo"; then
variant1=vuln
[ -z "$variant2" ] && variant2=immune
variant3=vuln
fi
if [ "$capabilities_rdcl_no" = 1 ]; then
# capability bit for future Intel processor that will explicitly state
# that they're not vulnerable to Meltdown
# this var is set in check_cpu()
[ -z "$variant3" ] && variant3=immune
[ -z "$variantl1tf" ] && variantl1tf=immune
_debug "is_cpu_vulnerable: RDCL_NO is set so not vuln to meltdown nor l1tf"
fi
if [ "$capabilities_ssb_no" = 1 ]; then
# capability bit for future Intel processor that will explicitly state
# that they're not vulnerable to Variant 4
# this var is set in check_cpu()
[ -z "$variant4" ] && variant4=immune
_debug "is_cpu_vulnerable: SSB_NO is set so not vuln to variant4"
fi
if is_cpu_ssb_free; then
[ -z "$variant4" ] && variant4=immune
_debug "is_cpu_vulnerable: cpu not affected by speculative store bypass so not vuln to variant4"
fi
# variant 4a for xeon phi
if [ "$cpu_family" = 6 ]; then
if [ "$cpu_model" = "$INTEL_FAM6_XEON_PHI_KNL" ] || [ "$cpu_model" = "$INTEL_FAM6_XEON_PHI_KNM" ]; then
_debug "is_cpu_vulnerable: xeon phi immune to variant 3a"
[ -z "$variant3a" ] && variant3a=immune
fi
fi
# L1TF (RDCL_NO already checked above)
if [ "$cpu_family" = 6 ]; then
if [ "$cpu_model" = "$INTEL_FAM6_ATOM_CEDARVIEW" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_CLOVERVIEW" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_LINCROFT" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_PENWELL" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_PINEVIEW" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_SILVERMONT1" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_SILVERMONT2" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_AIRMONT" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_MERRIFIELD" ] || \
[ "$cpu_model" = "$INTEL_FAM6_XEON_PHI_KNL" ] || \
[ "$cpu_model" = "$INTEL_FAM6_XEON_PHI_KNM" ]; then
_debug "is_cpu_vulnerable: intel family 6 but model known to be immune"
[ -z "$variantl1tf" ] && variantl1tf=immune
else
_debug "is_cpu_vulnerable: intel family 6 is vuln"
variantl1tf=vuln
fi
elif [ "$cpu_family" -lt 6 ]; then
_debug "is_cpu_vulnerable: intel family < 6 is immune"
[ -z "$variantl1tf" ] && variantl1tf=immune
fi
elif is_amd; then
# AMD revised their statement about variant2 => vulnerable
# https://www.amd.com/en/corporate/speculative-execution
variant1=vuln
variant2=vuln
[ -z "$variant3" ] && variant3=immune
# https://www.amd.com/en/corporate/security-updates
# "We have not identified any AMD x86 products susceptible to the Variant 3a vulnerability in our analysis to-date."
[ -z "$variant3a" ] && variant3a=immune
if is_cpu_ssb_free; then
[ -z "$variant4" ] && variant4=immune
_debug "is_cpu_vulnerable: cpu not affected by speculative store bypass so not vuln to variant4"
fi
variantl1tf=immune
elif [ "$cpu_vendor" = CAVIUM ]; then
variant3=immune
variant3a=immune
variantl1tf=immune
elif [ "$cpu_vendor" = ARM ]; then
# ARM
# reference: https://developer.arm.com/support/security-update
# some devices (phones or other) have several ARMs and as such different part numbers,
# an example is "bigLITTLE". we shouldn't rely on the first CPU only, so we check the whole list
i=0
for cpupart in $cpu_part_list
do
i=$(( i + 1 ))
# do NOT quote $cpu_arch_list below
# shellcheck disable=SC2086
cpuarch=$(echo $cpu_arch_list | awk '{ print $'$i' }')
_debug "checking cpu$i: <$cpupart> <$cpuarch>"
# some kernels report AArch64 instead of 8
[ "$cpuarch" = "AArch64" ] && cpuarch=8
if [ -n "$cpupart" ] && [ -n "$cpuarch" ]; then
# Cortex-R7 and Cortex-R8 are real-time and only used in medical devices or such
# I can't find their CPU part number, but it's probably not that useful anyway
# model R7 R8 A8 A9 A12 A15 A17 A57 A72 A73 A75 A76
# part ? ? c08 c09 c0d c0f c0e d07 d08 d09 d0a d0b?
# arch 7? 7? 7 7 7 7 7 8 8 8 8 8
#
# Whitelist identified non-vulnerable processors, use vulnerability information from
# https://developer.arm.com/support/arm-security-updates/speculative-processor-vulnerability
#
# Maintain cumulative check of vulnerabilities -
# if at least one of the cpu is vulnerable, then the system is vulnerable
if [ "$cpuarch" = 7 ] && echo "$cpupart" | grep -q -w -e 0xc08 -e 0xc09 -e 0xc0d -e 0xc0e; then
variant1=vuln
variant2=vuln
[ -z "$variant3" ] && variant3=immune
[ -z "$variant3a" ] && variant3a=immune
[ -z "$variant4" ] && variant4=immune
_debug "checking cpu$i: armv7 A8/A9/A12/A17 non vulnerable to variants 3, 3a & 4"
elif [ "$cpuarch" = 7 ] && echo "$cpupart" | grep -q -w -e 0xc0f; then
variant1=vuln
variant2=vuln
[ -z "$variant3" ] && variant3=immune
variant3a=vuln
[ -z "$variant4" ] && variant4=immune
_debug "checking cpu$i: armv7 A15 non vulnerable to variants 3 & 4"
elif [ "$cpuarch" = 8 ] && echo "$cpupart" | grep -q -w -e 0xd07 -e 0xd08; then
variant1=vuln
variant2=vuln
[ -z "$variant3" ] && variant3=immune
variant3a=vuln
variant4=vuln
_debug "checking cpu$i: armv8 A57/A72 non vulnerable to variants 3"
elif [ "$cpuarch" = 8 ] && echo "$cpupart" | grep -q -w -e 0xd09; then
variant1=vuln
variant2=vuln
[ -z "$variant3" ] && variant3=immune
[ -z "$variant3a" ] && variant3a=immune
variant4=vuln
_debug "checking cpu$i: armv8 A73 non vulnerable to variants 3 & 3a"
elif [ "$cpuarch" = 8 ] && echo "$cpupart" | grep -q -w -e 0xd0a; then
variant1=vuln
variant2=vuln
variant3=vuln
[ -z "$variant3a" ] && variant3a=immune
variant4=vuln
_debug "checking cpu$i: armv8 A75 non vulnerable to variant 3a"
elif [ "$cpuarch" = 8 ] && echo "$cpupart" | grep -q -w -e 0xd0b; then
variant1=vuln
[ -z "$variant2" ] && variant2=immune
[ -z "$variant3" ] && variant3=immune
[ -z "$variant3a" ] && variant3a=immune
variant4=vuln
_debug "checking cpu$i: armv8 A76 non vulnerable to variant 2, 3 & 3a"
elif [ "$cpuarch" -le 7 ] || ( [ "$cpuarch" = 8 ] && [ $(( cpupart )) -lt $(( 0xd07 )) ] ) ; then
[ -z "$variant1" ] && variant1=immune
[ -z "$variant2" ] && variant2=immune
[ -z "$variant3" ] && variant3=immune
[ -z "$variant3a" ] && variant3a=immune
[ -z "$variant4" ] && variant4=immune
_debug "checking cpu$i: arm arch$cpuarch, all immune (v7 or v8 and model < 0xd07)"
else
variant1=vuln
variant2=vuln
variant3=vuln
variant3a=vuln
variant4=vuln
_debug "checking cpu$i: arm unknown arch$cpuarch part$cpupart, considering vuln"
fi
fi
_debug "is_cpu_vulnerable: for cpu$i and so far, we have <$variant1> <$variant2> <$variant3> <$variant3a> <$variant4>"
done
variantl1tf=immune
fi
_debug "is_cpu_vulnerable: temp results are <$variant1> <$variant2> <$variant3> <$variant3a> <$variant4> <$variantl1tf>"
[ "$variant1" = "immune" ] && variant1=1 || variant1=0
[ "$variant2" = "immune" ] && variant2=1 || variant2=0
[ "$variant3" = "immune" ] && variant3=1 || variant3=0
[ "$variant3a" = "immune" ] && variant3a=1 || variant3a=0
[ "$variant4" = "immune" ] && variant4=1 || variant4=0
[ "$variantl1tf" = "immune" ] && variantl1tf=1 || variantl1tf=0
[ "$variantl1tf" = "immune" ] && variantl1tf_sgx=1 || variantl1tf_sgx=0
# even if we are vulnerable to L1TF, if there's no SGX, we're safe for the original foreshadow
[ "$cpuid_sgx" = 0 ] && variantl1tf_sgx=1
_debug "is_cpu_vulnerable: final results are <$variant1> <$variant2> <$variant3> <$variant3a> <$variant4> <$variantl1tf> <$variantl1tf_sgx>"
is_cpu_vulnerable_cached=1
_is_cpu_vulnerable_cached "$1"
return $?
}
is_cpu_specex_free()
{
# return true (0) if the CPU doesn't do speculative execution, false (1) if it does.
# if it's not in the list we know, return false (1).
# source: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/kernel/cpu/common.c#n882
# { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CEDARVIEW, X86_FEATURE_ANY },
# { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CLOVERVIEW, X86_FEATURE_ANY },
# { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_LINCROFT, X86_FEATURE_ANY },
# { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PENWELL, X86_FEATURE_ANY },
# { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PINEVIEW, X86_FEATURE_ANY },
# { X86_VENDOR_CENTAUR, 5 },
# { X86_VENDOR_INTEL, 5 },
# { X86_VENDOR_NSC, 5 },
# { X86_VENDOR_ANY, 4 },
parse_cpu_details
if is_intel; then
if [ "$cpu_family" = 6 ]; then
if [ "$cpu_model" = "$INTEL_FAM6_ATOM_CEDARVIEW" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_CLOVERVIEW" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_LINCROFT" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_PENWELL" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_PINEVIEW" ]; then
return 0
fi
elif [ "$cpu_family" = 5 ]; then
return 0
fi
fi
[ "$cpu_family" = 4 ] && return 0
return 1
}
is_cpu_ssb_free()
{
# return true (0) if the CPU isn't affected by speculative store bypass, false (1) if it does.
# if it's not in the list we know, return false (1).
# source1: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/kernel/cpu/common.c#n945
# source2: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/tree/arch/x86/kernel/cpu/common.c
# Only list CPUs that speculate but are immune, to avoid duplication of cpus listed in is_cpu_specex_free()
#{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1 },
#{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT },
#{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT2 },
#{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_MERRIFIELD },
#{ X86_VENDOR_INTEL, 6, INTEL_FAM6_CORE_YONAH },
#{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNL },
#{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNM },
#{ X86_VENDOR_AMD, 0x12, },
#{ X86_VENDOR_AMD, 0x11, },
#{ X86_VENDOR_AMD, 0x10, },
#{ X86_VENDOR_AMD, 0xf, },
parse_cpu_details
if is_intel; then
if [ "$cpu_family" = 6 ]; then
if [ "$cpu_model" = "$INTEL_FAM6_ATOM_AIRMONT" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_SILVERMONT1" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_SILVERMONT2" ] || \
[ "$cpu_model" = "$INTEL_FAM6_ATOM_MERRIFIELD" ]; then
return 0
elif [ "$cpu_model" = "$INTEL_FAM6_CORE_YONAH" ] || \
[ "$cpu_model" = "$INTEL_FAM6_XEON_PHI_KNL" ] || \
[ "$cpu_model" = "$INTEL_FAM6_XEON_PHI_KNM" ]; then
return 0
fi
fi
fi
if is_amd; then
if [ "$cpu_family" = "18" ] || \
[ "$cpu_family" = "17" ] || \
[ "$cpu_family" = "16" ] || \
[ "$cpu_family" = "15" ]; then
return 0
fi
fi
[ "$cpu_family" = 4 ] && return 0
return 1
}
show_header()
{
_info "Spectre and Meltdown mitigation detection tool v$VERSION"
_info
}
parse_opt_file()
{
# parse_opt_file option_name option_value
option_name="$1"
option_value="$2"
if [ -z "$option_value" ]; then
show_header
show_usage
echo "$0: error: --$option_name expects one parameter (a file)" >&2
exit 1
elif [ ! -e "$option_value" ]; then
show_header
echo "$0: error: couldn't find file $option_value" >&2
exit 1
elif [ ! -f "$option_value" ]; then
show_header
echo "$0: error: $option_value is not a file" >&2
exit 1
elif [ ! -r "$option_value" ]; then
show_header
echo "$0: error: couldn't read $option_value (are you root?)" >&2
exit 1
fi
echo "$option_value"
exit 0
}
while [ -n "$1" ]; do
if [ "$1" = "--kernel" ]; then
opt_kernel=$(parse_opt_file kernel "$2"); ret=$?
[ $ret -ne 0 ] && exit 255
shift 2
opt_live=0
elif [ "$1" = "--config" ]; then
opt_config=$(parse_opt_file config "$2"); ret=$?
[ $ret -ne 0 ] && exit 255
shift 2
opt_live=0
elif [ "$1" = "--map" ]; then
opt_map=$(parse_opt_file map "$2"); ret=$?
[ $ret -ne 0 ] && exit 255
shift 2
opt_live=0
elif [ "$1" = "--arch-prefix" ]; then
opt_arch_prefix="$2"
shift 2
elif [ "$1" = "--live" ]; then
opt_live_explicit=1
shift
elif [ "$1" = "--no-color" ]; then
opt_no_color=1
shift
elif [ "$1" = "--no-sysfs" ]; then
opt_no_sysfs=1
shift
elif [ "$1" = "--sysfs-only" ]; then
opt_sysfs_only=1
shift
elif [ "$1" = "--coreos" ]; then
opt_coreos=1
shift
elif [ "$1" = "--coreos-within-toolbox" ]; then
# don't use directly: used internally by --coreos
opt_coreos=0
shift
elif [ "$1" = "--paranoid" ]; then
opt_paranoid=1
shift
elif [ "$1" = "--hw-only" ]; then
opt_hw_only=1
shift
elif [ "$1" = "--no-hw" ]; then
opt_no_hw=1
shift
elif [ "$1" = "--no-explain" ]; then
# deprecated, kept for compatibility
opt_explain=0
shift
elif [ "$1" = "--explain" ]; then
opt_explain=1
shift
elif [ "$1" = "--batch" ]; then
opt_batch=1
opt_verbose=0
opt_no_color=1
shift
case "$1" in
text|short|nrpe|json|prometheus) opt_batch_format="$1"; shift;;
--*) ;; # allow subsequent flags
'') ;; # allow nothing at all
*)
echo "$0: error: unknown batch format '$1'" >&2
echo "$0: error: --batch expects a format from: text, nrpe, json" >&2
exit 255
;;
esac
elif [ "$1" = "-v" ] || [ "$1" = "--verbose" ]; then
opt_verbose=$(( opt_verbose + 1 ))
shift
elif [ "$1" = "--cve" ]; then
if [ -z "$2" ]; then
echo "$0: error: option --cve expects a parameter, supported CVEs are: $supported_cve_list" >&2
exit 255
fi
selected_cve=$(echo "$supported_cve_list" | grep -iwo "$2")
if [ -n "$selected_cve" ]; then
opt_cve_list="$opt_cve_list $selected_cve"
opt_cve_all=0
else
echo "$0: error: unsupported CVE specified ('$2'), supported CVEs are: $supported_cve_list" >&2
exit 255
fi
shift 2
elif [ "$1" = "--vmm" ]; then
if [ -z "$2" ]; then
echo "$0: error: option --vmm (auto, yes, no)" >&2
exit 255
fi
case "$2" in
auto) opt_vmm=-1;;
yes) opt_vmm=1;;
no) opt_vmm=0;;
esac
shift 2
elif [ "$1" = "--variant" ]; then
if [ -z "$2" ]; then
echo "$0: error: option --variant expects a parameter (1, 2, 3, 3a, 4 or l1tf)" >&2
exit 255
fi
case "$2" in
1) opt_cve_list="$opt_cve_list CVE-2017-5753"; opt_cve_all=0;;
2) opt_cve_list="$opt_cve_list CVE-2017-5715"; opt_cve_all=0;;
3) opt_cve_list="$opt_cve_list CVE-2017-5754"; opt_cve_all=0;;
3a) opt_cve_list="$opt_cve_list CVE-2018-3640"; opt_cve_all=0;;
4) opt_cve_list="$opt_cve_list CVE-2018-3639"; opt_cve_all=0;;
l1tf) opt_cve_list="$opt_cve_list CVE-2018-3615 CVE-2018-3620 CVE-2018-3646"; opt_cve_all=0;;
*)
echo "$0: error: invalid parameter '$2' for --variant, expected either 1, 2, 3, 3a, 4 or l1tf" >&2;
exit 255
;;
esac
shift 2
elif [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
show_header
show_usage
exit 0
elif [ "$1" = "--version" ]; then
opt_no_color=1
show_header
exit 0
elif [ "$1" = "--disclaimer" ]; then
show_header
show_disclaimer
exit 0
else
show_header
show_usage
echo "$0: error: unknown option '$1'"
exit 255
fi
done
show_header
if [ "$opt_no_sysfs" = 1 ] && [ "$opt_sysfs_only" = 1 ]; then
_warn "Incompatible options specified (--no-sysfs and --sysfs-only), aborting"
exit 255
fi
if [ "$opt_no_hw" = 1 ] && [ "$opt_hw_only" = 1 ]; then
_warn "Incompatible options specified (--no-hw and --hw-only), aborting"
exit 255
fi
# print status function
pstatus()
{
if [ "$opt_no_color" = 1 ]; then
_info_nol "$2"
else
case "$1" in
red) col="\033[41m\033[30m";;
green) col="\033[42m\033[30m";;
yellow) col="\033[43m\033[30m";;
blue) col="\033[44m\033[30m";;
*) col="";;
esac
_info_nol "$col $2 \033[0m"
fi
[ -n "$3" ] && _info_nol " ($3)"
_info
unset col
}
# Print the final status of a vulnerability (incl. batch mode)
# Arguments are: CVE UNK/OK/VULN description
pvulnstatus()
{
pvulnstatus_last_cve="$1"
if [ "$opt_batch" = 1 ]; then
case "$1" in
CVE-2017-5753) aka="SPECTRE VARIANT 1";;
CVE-2017-5715) aka="SPECTRE VARIANT 2";;
CVE-2017-5754) aka="MELTDOWN";;
CVE-2018-3640) aka="VARIANT 3A";;
CVE-2018-3639) aka="VARIANT 4";;
CVE-2018-3615/3620/3646) aka="L1TF";;
esac
case "$opt_batch_format" in
text) _echo 0 "$1: $2 ($3)";;
short) short_output="${short_output}$1 ";;
json)
case "$2" in
UNK) is_vuln="null";;
VULN) is_vuln="true";;
OK) is_vuln="false";;
esac
json_output="${json_output:-[}{\"NAME\":\"$aka\",\"CVE\":\"$1\",\"VULNERABLE\":$is_vuln,\"INFOS\":\"$3\"},"
;;
nrpe) [ "$2" = VULN ] && nrpe_vuln="$nrpe_vuln $1";;
prometheus)
prometheus_output="${prometheus_output:+$prometheus_output\n}specex_vuln_status{name=\"$aka\",cve=\"$1\",status=\"$2\",info=\"$3\"} 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' "$@"; final_summary="$final_summary \033[43m\033[30m$pvulnstatus_last_cve:??\033[0m";;
VULN) pstatus red 'VULNERABLE' "$@"; final_summary="$final_summary \033[41m\033[30m$pvulnstatus_last_cve:KO\033[0m";;
OK) pstatus green 'NOT VULNERABLE' "$@"; final_summary="$final_summary \033[42m\033[30m$pvulnstatus_last_cve:OK\033[0m";;
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).
# ----------------------------------------------------------------------
kernel=''
kernel_err=''
check_kernel()
{
_file="$1"
_desperate_mode="$2"
# checking the return code of readelf -h is not enough, we could get
# a damaged ELF file and validate it, check for stderr warnings too
_readelf_warnings=$("${opt_arch_prefix}readelf" -S "$_file" 2>&1 >/dev/null | tr "\n" "/"); ret=$?
_readelf_sections=$("${opt_arch_prefix}readelf" -S "$_file" 2>/dev/null | grep -c -e data -e text -e init)
_kernel_size=$(stat -c %s "$_file" 2>/dev/null || stat -f %z "$_file" 2>/dev/null || echo 10000)
_debug "check_kernel: ret=$? size=$_kernel_size sections=$_readelf_sections warnings=$_readelf_warnings"
if [ -n "$_desperate_mode" ]; then
if "${opt_arch_prefix}strings" "$_file" | grep -Eq '^Linux version '; then
_debug "check_kernel (desperate): ... matched!"
return 0
else
_debug "check_kernel (desperate): ... invalid"
fi
else
if [ $ret -eq 0 ] && [ -z "$_readelf_warnings" ] && [ "$_readelf_sections" -gt 0 ]; then
if [ "$_kernel_size" -ge 100000 ]; then
_debug "check_kernel: ... file is valid"
return 0
else
_debug "check_kernel: ... file seems valid but is too small, ignoring"
fi
else
_debug "check_kernel: ... file is invalid"
fi
fi
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
_debug "try_decompress: looking for $3 magic in $6"
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
kernel_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 $4 > "$kerneltmp" 2>/dev/null; ret=$?
if [ ! -s "$kerneltmp" ]; then
# don't rely on $ret, sometimes it's != 0 but worked
# (e.g. gunzip ret=2 just means there was trailing garbage)
_debug "try_decompress: decompression with $3 failed (err=$ret)"
elif check_kernel "$kerneltmp" "$7"; then
kernel="$kerneltmp"
_debug "try_decompress: decompressed with $3 successfully!"
return 0
elif [ "$3" != "cat" ]; then
_debug "try_decompress: decompression with $3 worked but result is not a kernel, trying with an offset"
[ -z "$kerneltmp2" ] && kerneltmp2=$(mktemp /tmp/kernel-XXXXXX)
cat "$kerneltmp" > "$kerneltmp2"
try_decompress '\177ELF' xxy 'cat' '' cat "$kerneltmp2" && return 0
else
_debug "try_decompress: decompression with $3 worked but result is not a kernel"
fi
done
return 1
}
extract_kernel()
{
[ -n "$1" ] || return 1
# Prepare temp files:
kerneltmp="$(mktemp /tmp/kernel-XXXXXX)"
# Initial attempt for uncompressed images or objects:
if check_kernel "$1"; then
cat "$1" > "$kerneltmp"
kernel=$kerneltmp
return 0
fi
# That didn't work, so retry after decompression.
for mode in '' 'desperate'; do
try_decompress '\037\213\010' xy gunzip '' gunzip "$1" "$mode" && return 0
try_decompress '\3757zXZ\000' abcde unxz '' xz-utils "$1" "$mode" && return 0
try_decompress 'BZh' xy bunzip2 '' bzip2 "$1" "$mode" && return 0
try_decompress '\135\0\0\0' xxx unlzma '' xz-utils "$1" "$mode" && return 0
try_decompress '\211\114\132' xy 'lzop' '-d' lzop "$1" "$mode" && return 0
try_decompress '\002\041\114\030' xyy 'lz4' '-d -l' liblz4-tool "$1" "$mode" && return 0
try_decompress '\177ELF' xxy 'cat' '' cat "$1" "$mode" && return 0
done
_verbose "Couldn't extract the kernel image, accuracy might be reduced"
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
}
load_msr()
{
if [ "$os" = Linux ]; then
if ! grep -e msr /proc/modules 2>/dev/null; then
modprobe msr 2>/dev/null && insmod_msr=1
_debug "attempted to load module msr, insmod_msr=$insmod_msr"
else
_debug "msr module already loaded"
fi
else
if ! kldstat -q -m cpuctl; then
kldload cpuctl 2>/dev/null && kldload_cpuctl=1
_debug "attempted to load module cpuctl, kldload_cpuctl=$kldload_cpuctl"
else
_debug "cpuctl module already loaded"
fi
fi
}
load_cpuid()
{
if [ "$os" = Linux ]; then
if ! grep -e cpuid /proc/modules 2>/dev/null; then
modprobe cpuid 2>/dev/null && insmod_cpuid=1
_debug "attempted to load module cpuid, insmod_cpuid=$insmod_cpuid"
else
_debug "cpuid module already loaded"
fi
else
if ! kldstat -q -m cpuctl; then
kldload cpuctl 2>/dev/null && kldload_cpuctl=1
_debug "attempted to load module cpuctl, kldload_cpuctl=$kldload_cpuctl"
else
_debug "cpuctl module already loaded"
fi
fi
}
# shellcheck disable=SC2034
EAX=1; EBX=2; ECX=3; EDX=4;
read_cpuid()
{
# leaf is the value of the eax register when calling the cpuid instruction:
_leaf="$1"
# eax=1 ebx=2 ecx=3 edx=4:
_register="$2"
# number of bits to shift the register right to:
_shift="$3"
# mask to apply as an AND operand to the shifted register value
_mask="$4"
# wanted value (optional), if present we return 0(true) if the obtained value is equal, 1 otherwise:
_wanted="$5"
# in any case, the read value is globally available in $read_cpuid_value
read_cpuid_value=''
if [ ! -e /dev/cpu/0/cpuid ] && [ ! -e /dev/cpuctl0 ]; then
# try to load the module ourselves (and remember it so we can rmmod it afterwards)
load_cpuid
fi
if [ -e /dev/cpu/0/cpuid ]; then
# Linux
# on some kernel versions, /dev/cpu/0/cpuid doesn't imply that the cpuid module is loaded, in that case dd returns an error
dd if=/dev/cpu/0/cpuid bs=16 count=1 >/dev/null 2>&1 || load_cpuid
# we need _leaf to be converted to decimal for dd
_leaf=$(( _leaf ))
# to avoid using iflag=skip_bytes, which doesn't exist on old versions of dd, seek to the closer multiple-of-16
_ddskip=$(( _leaf / 16 ))
_odskip=$(( _leaf - _ddskip * 16 ))
# now read the value
_cpuid=$(dd if=/dev/cpu/0/cpuid bs=16 skip=$_ddskip count=$((_odskip + 1)) 2>/dev/null | od -j $((_odskip * 16)) -A n -t u4)
elif [ -e /dev/cpuctl0 ]; then
# BSD
_cpuid=$(cpucontrol -i "$_leaf" /dev/cpuctl0 2>/dev/null | awk '{print $4,$5,$6,$7}')
# cpuid level 0x1: 0x000306d4 0x00100800 0x4dfaebbf 0xbfebfbff
else
return 2
fi
_debug "cpuid: leaf$_leaf on cpu0, eax-ebx-ecx-edx: $_cpuid"
[ -z "$_cpuid" ] && return 2
# get the value of the register we want
_reg=$(echo "$_cpuid" | awk '{print $'"$_register"'}')
# Linux returns it as decimal, BSD as hex, normalize to decimal
_reg=$(( _reg ))
# shellcheck disable=SC2046
_debug "cpuid: wanted register ($_register) has value $_reg aka "$(printf "%08x" "$_reg")
_reg_shifted=$(( _reg >> _shift ))
# shellcheck disable=SC2046
_debug "cpuid: shifted value by $_shift is $_reg_shifted aka "$(printf "%x" "$_reg_shifted")
read_cpuid_value=$(( _reg_shifted & _mask ))
# shellcheck disable=SC2046
_debug "cpuid: after AND $_mask, final value is $read_cpuid_value aka "$(printf "%x" "$read_cpuid_value")
if [ -n "$_wanted" ]; then
_debug "cpuid: wanted $_wanted and got $read_cpuid_value"
if [ "$read_cpuid_value" = "$_wanted" ]; then
return 0
else
return 1
fi
fi
return 0
}
dmesg_grep()
{
# grep for something in dmesg, ensuring that the dmesg buffer
# has not been truncated
dmesg_grepped=''
if ! dmesg | grep -qE -e '(^|\] )Linux version [0-9]' -e '^FreeBSD is a registered' ; 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 $dmesg_grepped
return 0
}
is_coreos()
{
which coreos-install >/dev/null 2>&1 && which toolbox >/dev/null 2>&1 && return 0
return 1
}
parse_cpu_details()
{
[ "$parse_cpu_details_done" = 1 ] && return 0
if [ -e "$procfs/cpuinfo" ]; then
cpu_vendor=$( grep '^vendor_id' "$procfs/cpuinfo" | awk '{print $3}' | head -1)
cpu_friendly_name=$(grep '^model name' "$procfs/cpuinfo" | cut -d: -f2- | head -1 | sed -e 's/^ *//')
# special case for ARM follows
if grep -qi 'CPU implementer[[:space:]]*:[[:space:]]*0x41' "$procfs/cpuinfo"; then
cpu_vendor='ARM'
# some devices (phones or other) have several ARMs and as such different part numbers,
# an example is "bigLITTLE", so we need to store the whole list, this is needed for is_cpu_vulnerable
cpu_part_list=$(awk '/CPU part/ {print $4}' "$procfs/cpuinfo")
cpu_arch_list=$(awk '/CPU architecture/ {print $3}' "$procfs/cpuinfo")
# take the first one to fill the friendly name, do NOT quote the vars below
# shellcheck disable=SC2086
cpu_arch=$(echo $cpu_arch_list | awk '{ print $1 }')
# shellcheck disable=SC2086
cpu_part=$(echo $cpu_part_list | awk '{ print $1 }')
[ "$cpu_arch" = "AArch64" ] && cpu_arch=8
cpu_friendly_name="ARM"
[ -n "$cpu_arch" ] && cpu_friendly_name="$cpu_friendly_name v$cpu_arch"
[ -n "$cpu_part" ] && cpu_friendly_name="$cpu_friendly_name model $cpu_part"
elif grep -qi 'CPU implementer[[:space:]]*:[[:space:]]*0x43' "$procfs/cpuinfo"; then
cpu_vendor='CAVIUM'
fi
cpu_family=$( grep '^cpu family' "$procfs/cpuinfo" | awk '{print $4}' | grep -E '^[0-9]+$' | head -1)
cpu_model=$( grep '^model' "$procfs/cpuinfo" | awk '{print $3}' | grep -E '^[0-9]+$' | head -1)
cpu_stepping=$(grep '^stepping' "$procfs/cpuinfo" | awk '{print $3}' | grep -E '^[0-9]+$' | head -1)
cpu_ucode=$( grep '^microcode' "$procfs/cpuinfo" | awk '{print $3}' | head -1)
else
cpu_friendly_name=$(sysctl -n hw.model)
fi
# get raw cpuid, it's always useful (referenced in the Intel doc for firmware updates for example)
if read_cpuid 0x1 $EAX 0 0xFFFFFFFF; then
cpu_cpuid="$read_cpuid_value"
fi
# under BSD, linprocfs often doesn't export ucode information, so fetch it ourselves the good old way
if [ -z "$cpu_ucode" ] && [ "$os" != Linux ]; then
load_cpuid
if [ -e /dev/cpuctl0 ]; then
# init MSR with NULLs
cpucontrol -m 0x8b=0 /dev/cpuctl0
# call CPUID
cpucontrol -i 1 /dev/cpuctl0 >/dev/null
# read MSR
cpu_ucode=$(cpucontrol -m 0x8b /dev/cpuctl0 | awk '{print $3}')
# convert to decimal
cpu_ucode=$(( cpu_ucode ))
# convert back to hex
cpu_ucode=$(printf "0x%x" "$cpu_ucode")
fi
fi
echo "$cpu_ucode" | grep -q ^0x && cpu_ucode=$(( cpu_ucode ))
ucode_found=$(printf "model 0x%x family 0x%x stepping 0x%x ucode 0x%x cpuid 0x%x" "$cpu_model" "$cpu_family" "$cpu_stepping" "$cpu_ucode" "$cpu_cpuid")
# also define those that we will need in other funcs
# taken from ttps://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/include/asm/intel-family.h
# shellcheck disable=SC2034
{
INTEL_FAM6_CORE_YONAH=$(( 0x0E ))
INTEL_FAM6_CORE2_MEROM=$(( 0x0F ))
INTEL_FAM6_CORE2_MEROM_L=$(( 0x16 ))
INTEL_FAM6_CORE2_PENRYN=$(( 0x17 ))
INTEL_FAM6_CORE2_DUNNINGTON=$(( 0x1D ))
INTEL_FAM6_NEHALEM=$(( 0x1E ))
INTEL_FAM6_NEHALEM_G=$(( 0x1F ))
INTEL_FAM6_NEHALEM_EP=$(( 0x1A ))
INTEL_FAM6_NEHALEM_EX=$(( 0x2E ))
INTEL_FAM6_WESTMERE=$(( 0x25 ))
INTEL_FAM6_WESTMERE_EP=$(( 0x2C ))
INTEL_FAM6_WESTMERE_EX=$(( 0x2F ))
INTEL_FAM6_SANDYBRIDGE=$(( 0x2A ))
INTEL_FAM6_SANDYBRIDGE_X=$(( 0x2D ))
INTEL_FAM6_IVYBRIDGE=$(( 0x3A ))
INTEL_FAM6_IVYBRIDGE_X=$(( 0x3E ))
INTEL_FAM6_HASWELL_CORE=$(( 0x3C ))
INTEL_FAM6_HASWELL_X=$(( 0x3F ))
INTEL_FAM6_HASWELL_ULT=$(( 0x45 ))
INTEL_FAM6_HASWELL_GT3E=$(( 0x46 ))
INTEL_FAM6_BROADWELL_CORE=$(( 0x3D ))
INTEL_FAM6_BROADWELL_GT3E=$(( 0x47 ))
INTEL_FAM6_BROADWELL_X=$(( 0x4F ))
INTEL_FAM6_BROADWELL_XEON_D=$(( 0x56 ))
INTEL_FAM6_SKYLAKE_MOBILE=$(( 0x4E ))
INTEL_FAM6_SKYLAKE_DESKTOP=$(( 0x5E ))
INTEL_FAM6_SKYLAKE_X=$(( 0x55 ))
INTEL_FAM6_KABYLAKE_MOBILE=$(( 0x8E ))
INTEL_FAM6_KABYLAKE_DESKTOP=$(( 0x9E ))
# /* "Small Core" Processors (Atom) */
INTEL_FAM6_ATOM_PINEVIEW=$(( 0x1C ))
INTEL_FAM6_ATOM_LINCROFT=$(( 0x26 ))
INTEL_FAM6_ATOM_PENWELL=$(( 0x27 ))
INTEL_FAM6_ATOM_CLOVERVIEW=$(( 0x35 ))
INTEL_FAM6_ATOM_CEDARVIEW=$(( 0x36 ))
INTEL_FAM6_ATOM_SILVERMONT1=$(( 0x37 ))
INTEL_FAM6_ATOM_SILVERMONT2=$(( 0x4D ))
INTEL_FAM6_ATOM_AIRMONT=$(( 0x4C ))
INTEL_FAM6_ATOM_MERRIFIELD=$(( 0x4A ))
INTEL_FAM6_ATOM_MOOREFIELD=$(( 0x5A ))
INTEL_FAM6_ATOM_GOLDMONT=$(( 0x5C ))
INTEL_FAM6_ATOM_DENVERTON=$(( 0x5F ))
INTEL_FAM6_ATOM_GEMINI_LAKE=$(( 0x7A ))
# /* Xeon Phi */
INTEL_FAM6_XEON_PHI_KNL=$(( 0x57 ))
INTEL_FAM6_XEON_PHI_KNM=$(( 0x85 ))
}
parse_cpu_details_done=1
}
is_amd()
{
[ "$cpu_vendor" = AuthenticAMD ] && return 0
return 1
}
is_intel()
{
[ "$cpu_vendor" = GenuineIntel ] && return 0
return 1
}
is_cpu_smt_enabled()
{
# SMT / HyperThreading is enabled if siblings != cpucores
if [ -e "$procfs/cpuinfo" ]; then
_siblings=$(awk '/^siblings/ {print $3;exit}' "$procfs/cpuinfo")
_cpucores=$(awk '/^cpu cores/ {print $4;exit}' "$procfs/cpuinfo")
if [ -n "$_siblings" ] && [ -n "$_cpucores" ]; then
if [ "$_siblings" = "$_cpucores" ]; then
return 1
else
return 0
fi
fi
fi
# we can't tell
return 2
}
is_ucode_blacklisted()
{
parse_cpu_details
# if it's not an Intel, don't bother: it's not blacklisted
is_intel || return 1
# it also needs to be family=6
[ "$cpu_family" = 6 ] || return 1
# now, check each known bad microcode
# source: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/x86/kernel/cpu/intel.c#n105
# 2018-02-08 update: https://newsroom.intel.com/wp-content/uploads/sites/11/2018/02/microcode-update-guidance.pdf
# model,stepping,microcode
for tuple in \
$INTEL_FAM6_KABYLAKE_DESKTOP,0x0B,0x80 \
$INTEL_FAM6_KABYLAKE_DESKTOP,0x0A,0x80 \
$INTEL_FAM6_KABYLAKE_DESKTOP,0x09,0x80 \
$INTEL_FAM6_KABYLAKE_MOBILE,0x0A,0x80 \
$INTEL_FAM6_KABYLAKE_MOBILE,0x09,0x80 \
$INTEL_FAM6_SKYLAKE_X,0x03,0x0100013e \
$INTEL_FAM6_SKYLAKE_X,0x04,0x02000036 \
$INTEL_FAM6_SKYLAKE_X,0x04,0x0200003a \
$INTEL_FAM6_SKYLAKE_X,0x04,0x0200003c \
$INTEL_FAM6_BROADWELL_CORE,0x04,0x28 \
$INTEL_FAM6_BROADWELL_GT3E,0x01,0x1b \
$INTEL_FAM6_BROADWELL_XEON_D,0x02,0x14 \
$INTEL_FAM6_BROADWELL_XEON_D,0x03,0x07000011 \
$INTEL_FAM6_BROADWELL_X,0x01,0x0b000023 \
$INTEL_FAM6_BROADWELL_X,0x01,0x0b000025 \
$INTEL_FAM6_HASWELL_ULT,0x01,0x21 \
$INTEL_FAM6_HASWELL_GT3E,0x01,0x18 \
$INTEL_FAM6_HASWELL_CORE,0x03,0x23 \
$INTEL_FAM6_HASWELL_X,0x02,0x3b \
$INTEL_FAM6_HASWELL_X,0x04,0x10 \
$INTEL_FAM6_IVYBRIDGE_X,0x04,0x42a \
$INTEL_FAM6_SANDYBRIDGE_X,0x06,0x61b \
$INTEL_FAM6_SANDYBRIDGE_X,0x07,0x712
do
model=$(echo $tuple | cut -d, -f1)
stepping=$(( $(echo $tuple | cut -d, -f2) ))
ucode=$(echo $tuple | cut -d, -f3)
echo "$ucode" | grep -q ^0x && ucode_decimal=$(( ucode ))
if [ "$cpu_model" = "$model" ] && [ "$cpu_stepping" = "$stepping" ]; then
if [ "$cpu_ucode" = "$ucode_decimal" ] || [ "$cpu_ucode" = "$ucode" ]; then
_debug "is_ucode_blacklisted: we have a match! ($cpu_model/$cpu_stepping/$cpu_ucode)"
return 0
fi
fi
done
_debug "is_ucode_blacklisted: no ($cpu_model/$cpu_stepping/$cpu_ucode)"
return 1
}
is_skylake_cpu()
{
# is this a skylake cpu?
# return 0 if yes, 1 otherwise
#if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
# boot_cpu_data.x86 == 6) {
# switch (boot_cpu_data.x86_model) {
# case INTEL_FAM6_SKYLAKE_MOBILE:
# case INTEL_FAM6_SKYLAKE_DESKTOP:
# case INTEL_FAM6_SKYLAKE_X:
# case INTEL_FAM6_KABYLAKE_MOBILE:
# case INTEL_FAM6_KABYLAKE_DESKTOP:
# return true;
parse_cpu_details
is_intel || return 1
[ "$cpu_family" = 6 ] || return 1
if [ "$cpu_model" = $INTEL_FAM6_SKYLAKE_MOBILE ] || \
[ "$cpu_model" = $INTEL_FAM6_SKYLAKE_DESKTOP ] || \
[ "$cpu_model" = $INTEL_FAM6_SKYLAKE_X ] || \
[ "$cpu_model" = $INTEL_FAM6_KABYLAKE_MOBILE ] || \
[ "$cpu_model" = $INTEL_FAM6_KABYLAKE_DESKTOP ]; then
return 0
fi
return 1
}
is_vulnerable_to_empty_rsb()
{
if is_intel && [ -z "$capabilities_rsba" ]; then
_warn "is_vulnerable_to_empty_rsb() called before ARCH CAPABILITIES MSR was read"
fi
if is_skylake_cpu || [ "$capabilities_rsba" = 1 ]; then
return 0
fi
return 1
}
is_zen_cpu()
{
# is this CPU from the AMD ZEN family ? (ryzen, epyc, ...)
parse_cpu_details
is_amd || return 1
[ "$cpu_family" = 23 ] && return 0
return 1
}
is_latest_known_ucode()
{
# 0: yes, 1: no, 2: unknown
parse_cpu_details
ucode_latest="latest microcode version for your CPU model is unknown"
is_intel || return 2
# https://www.intel.com/content/dam/www/public/us/en/documents/sa00115-microcode-update-guidance.pdf
# ps2txt sa00115-microcode-update-guidance.ps | grep -Eo '[0-9A-F]+ [0-9A-F]+ [^ ]+ Production 0x[A-F0-9]+ 0x[^ ]+' | awk '{print "0x"$1","$6" \\"}' | uniq
# cpuid,ucode
for tuple in \
0x106A5,0x1D \
0x106E5,0x0A \
0x20652,0x11 \
0x20655,0x7 \
0x206A7,0x2E \
0x206C2,0x1F \
0x206D6,0x61D \
0x206D7,0x714 \
0x206E6,0x0D \
0x206F2,0x3B \
0x306A9,0x20 \
0x306C3,0x25 \
0x306D4,0x2B \
0x306E4,0x42D \
0x306E7,0x714 \
0x306F2,0x3D \
0x306F4,0x12 \
0x40651,0x24 \
0x40661,0x1A \
0x40671,0x1E \
0x406E3,0xC6 \
0x406F1,0xB00002E \
0x50654,0x200004D \
0x50662,0x17 \
0x50663,0x7000013 \
0x50664,0xF000012 \
0x50665,0xE00000A \
0x506C2,0x14 \
0x506E3,0xC6 \
0x506F1,0x24 \
0x706A1,0x28 \
0x806E9,0x8E \
0x806EA,0x96 \
0x906E9,0x8E \
0x906EA,0x96 \
0x906EB,0x8E
do
cpuid_decimal=$(( $(echo "$tuple" | cut -d, -f1) ))
ucode_decimal=$(( $(echo "$tuple" | cut -d, -f2) ))
if [ "$cpuid_decimal" = "$cpu_cpuid" ]; then
_debug "is_latest_known_ucode: with cpuid $cpu_cpuid has ucode $cpu_ucode, last known is $cpuid_decimal"
ucode_latest=$(printf "latest known version is 0x%x according to Intel Microcode Guidance, August 8 2018" "$ucode_decimal")
if [ "$cpu_ucode" -ge "$ucode_decimal" ]; then
return 0
else
return 1
fi
fi
done
_debug "is_latest_known_ucode: this cpuid is not referenced ($cpu_cpuid)"
return 2
}
# ENTRYPOINT
# we can't do anything useful under WSL
if uname -a | grep -qE -- '-Microsoft #[0-9]+-Microsoft '; then
_warn "This script doesn't work under Windows Subsystem for Linux"
_warn "You should use the official Microsoft tool instead."
_warn "It can be found under https://aka.ms/SpeculationControlPS"
exit 1
fi
# 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 "$0: error: incompatible modes specified, use either --live or --kernel/--config/--map" >&2
exit 255
fi
fi
if [ "$opt_hw_only" = 1 ]; then
if [ "$opt_cve_all" = 0 ]; then
show_usage
echo "$0: error: incompatible modes specified, --hw-only vs --variant" >&2
exit 255
else
opt_cve_all=0
opt_cve_list=''
fi
fi
# coreos mode
if [ "$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 $* --coreos-within-toolbox"
exitcode=$?
exit $exitcode
else
if is_coreos; then
_warn "You seem to be running CoreOS, you might want to use the --coreos option for better results"
_warn
fi
fi
# if we're under a BSD, try to mount linprocfs for "$procfs/cpuinfo"
procfs=/proc
if echo "$os" | grep -q BSD; then
_debug "We're under BSD, check if we have procfs"
procfs=$(mount | awk '/^linprocfs/ { print $3; exit; }')
if [ -z "$procfs" ]; then
_debug "we don't, try to mount it"
procfs=/proc
[ -d /compat/linux/proc ] && procfs=/compat/linux/proc
test -d $procfs || mkdir $procfs
if mount -t linprocfs linprocfs $procfs 2>/dev/null; then
mounted_procfs=1
_debug "procfs just mounted at $procfs"
else
procfs=''
fi
else
_debug "We do: $procfs"
fi
fi
parse_cpu_details
if [ "$opt_live" = 1 ]; then
# root check (only for live mode, for offline mode, we already checked if we could read the files)
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) $(uname -m)\033[0m"
_info "CPU is \033[35m$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 the boot partition is within a btrfs subvolume, strip the subvolume name
# if /boot is a separate subvolume, the remainder of the code in this section should handle it
if echo "$opt_kernel" | grep -q "^/@"; then opt_kernel=$(echo "$opt_kernel" | sed "s:/@[^/]*::"); fi
# if we have a dedicated /boot partition, our bootloader might have just called it /
# so try to prepend /boot and see if we find anything
[ -e "/boot/$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"
# Arch aarch64:
[ -e "/boot/Image" ] && opt_kernel="/boot/Image"
# Arch armv5/armv7:
[ -e "/boot/zImage" ] && opt_kernel="/boot/zImage"
# Linux-Libre:
[ -e "/boot/vmlinuz-linux-libre" ] && opt_kernel="/boot/vmlinuz-linux-libre"
# pine64
[ -e "/boot/pine64/Image" ] && opt_kernel="/boot/pine64/Image"
# 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"
# systemd kernel-install:
[ -e "/etc/machine-id" ] && [ -e "/boot/$(cat /etc/machine-id)/$(uname -r)/linux" ] && opt_kernel="/boot/$(cat /etc/machine-id)/$(uname -r)/linux"
# Clear Linux:
str_uname=$(uname -r)
[ -e "/lib/kernel" ] && opt_kernel="/lib/kernel/org.clearlinux.${str_uname##*.}.${str_uname%.*}"
fi
# system.map
if [ -e /proc/kallsyms ] ; then
opt_map=/proc/kallsyms
elif [ -e "/lib/modules/$(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-$(uname -r)"
elif [ -e "/lib/kernel/config-$(uname -r)" ]; then
opt_config="/lib/kernel/config-$(uname -r)"
fi
# config
if [ -e /proc/config.gz ] ; then
dumped_config="$(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)"
elif [ -e "/etc/kernels/kernel-config-$(uname -m)-$(uname -r)" ]; then
opt_config="/etc/kernels/kernel-config-$(uname -m)-$(uname -r)"
fi
else
_info "Checking for vulnerabilities against specified kernel"
_info "CPU is \033[35m$cpu_friendly_name\033[0m"
fi
if [ -n "$opt_kernel" ]; then
_verbose "Will use kernel image \033[35m$opt_kernel\033[0m"
else
_verbose "Will use no kernel image (accuracy might be reduced)"
bad_accuracy=1
fi
if [ "$os" = Linux ]; then
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 [ "$bad_accuracy" = 1 ]; then
_info "We're missing some kernel info (see -v), accuracy might be reduced"
fi
fi
if [ -e "$opt_kernel" ]; then
if ! which "${opt_arch_prefix}readelf" >/dev/null 2>&1; then
_debug "readelf not found"
kernel_err="missing '${opt_arch_prefix}readelf' tool, please install it, usually it's in the 'binutils' package"
elif [ "$opt_sysfs_only" = 1 ]; then
kernel_err='kernel image decompression skipped'
else
extract_kernel "$opt_kernel"
fi
else
_debug "no opt_kernel defined"
kernel_err="couldn't find your kernel image in /boot, if you used netboot, this is normal"
fi
if [ -z "$kernel" ] || [ ! -r "$kernel" ]; then
[ -z "$kernel_err" ] && kernel_err="couldn't extract your kernel from $opt_kernel"
else
# vanilla kernels have with ^Linux version
# also try harder with some kernels (such as Red Hat) that don't have ^Linux version before their version string
# and check for FreeBSD
kernel_version=$("${opt_arch_prefix}strings" "$kernel" 2>/dev/null | grep -E \
-e '^Linux version ' \
-e '^[[:alnum:]][^[:space:]]+ \([^[:space:]]+\) #[0-9]+ .+ (19|20)[0-9][0-9]$' \
-e '^FreeBSD [0-9]' | head -1)
if [ -z "$kernel_version" ]; then
# try even harder with some kernels (such as ARM) that split the release (uname -r) and version (uname -v) in 2 adjacent strings
kernel_version=$("${opt_arch_prefix}strings" "$kernel" 2>/dev/null | grep -E -B1 '^#[0-9]+ .+ (19|20)[0-9][0-9]$' | tr "\n" " ")
fi
if [ -n "$kernel_version" ]; then
# in live mode, check if the img we found is the correct one
if [ "$opt_live" = 1 ]; then
_verbose "Kernel image is \033[35m$kernel_version"
if ! echo "$kernel_version" | grep -qF "$(uname -r)"; then
_warn "Possible disrepancy between your running kernel '$(uname -r)' and the image '$kernel_version' we found ($opt_kernel), results might be incorrect"
fi
else
_info "Kernel image is \033[35m$kernel_version"
fi
else
_verbose "Kernel image version is unknown"
fi
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()
{
file="$1"
regex="$2"
mode="$3"
[ "$opt_live" = 1 ] && [ "$opt_no_sysfs" = 0 ] && [ -r "$file" ] || return 1
[ -n "$regex" ] || regex='.*'
msg=$(grep -Eo "$regex" "$file")
if [ "$mode" = silent ]; then
_info "* Information from the /sys interface: $msg"
return 0
fi
_info_nol "* Mitigated according to the /sys interface: "
if echo "$msg" | grep -qi '^not affected'; then
# Not affected
status=OK
pstatus green YES "$msg"
elif echo "$msg" | grep -qi '^mitigation'; then
# Mitigation: PTI
status=OK
pstatus green YES "$msg"
elif echo "$msg" | grep -qi '^vulnerable'; then
# Vulnerable
status=VULN
pstatus yellow NO "$msg"
else
status=UNK
pstatus yellow UNKNOWN "$msg"
fi
_debug "sys_interface_check: $file=$msg (re=$regex)"
return 0
}
number_of_cpus()
{
if echo "$os" | grep -q BSD; then
n=$(sysctl -n hw.ncpu 2>/dev/null || echo 1)
elif [ -e "$procfs/cpuinfo" ]; then
n=$(grep -c ^processor "$procfs/cpuinfo" 2>/dev/null || echo 1)
else
# if we don't know, default to 1 CPU
n=1
fi
return "$n"
}
# $1 - msr number
# $2 - cpu index
write_msr()
{
# _msr must be in hex, in the form 0x1234:
_msr="$1"
# cpu index, starting from 0:
_cpu="$2"
if [ "$os" != Linux ]; then
cpucontrol -m "$_msr=0" "/dev/cpuctl$_cpu" >/dev/null 2>&1; ret=$?
else
# for Linux
# convert to decimal
_msr=$(( _msr ))
if [ ! -w /dev/cpu/"$_cpu"/msr ]; then
ret=200 # permission error
# if wrmsr is available, use it
elif which wrmsr >/dev/null 2>&1 && [ "$SMC_NO_WRMSR" != 1 ]; then
_debug "write_msr: using wrmsr"
wrmsr $_msr 0 2>/dev/null; ret=$?
# or if we have perl, use it, any 5.x version will work
elif which perl >/dev/null 2>&1 && [ "$SMC_NO_PERL" != 1 ]; then
_debug "write_msr: using perl"
ret=1
perl -e "open(M,'>','/dev/cpu/$_cpu/msr') and seek(M,$_msr,0) and exit(syswrite(M,pack('H16',0)))"; [ $? -eq 8 ] && ret=0
# fallback to dd if it supports seek_bytes
elif dd if=/dev/null of=/dev/null bs=8 count=1 seek="$_msr" oflag=seek_bytes 2>/dev/null; then
_debug "write_msr: using dd"
dd if=/dev/zero of=/dev/cpu/"$_cpu"/msr bs=8 count=1 seek="$_msr" oflag=seek_bytes 2>/dev/null; ret=$?
else
_debug "write_msr: got no wrmsr, perl or recent enough dd!"
return 201 # missing tool error
fi
fi
# normalize ret
[ "$ret" != 0 ] && ret=1
_debug "write_msr: for cpu $_cpu on msr $_msr, ret=$ret"
return $ret
}
read_msr()
{
# _msr must be in hex, in the form 0x1234:
_msr="$1"
# cpu index, starting from 0:
_cpu="$2"
read_msr_value=''
if [ "$os" != Linux ]; then
_msr=$(cpucontrol -m "$_msr" "/dev/cpuctl$_cpu" 2>/dev/null); ret=$?
[ $ret -ne 0 ] && return 1
# MSR 0x10: 0x000003e1 0xb106dded
_msr_h=$(echo "$_msr" | awk '{print $3}');
_msr_h="$(( _msr_h >> 24 & 0xFF )) $(( _msr_h >> 16 & 0xFF )) $(( _msr_h >> 8 & 0xFF )) $(( _msr_h & 0xFF ))"
_msr_l=$(echo "$_msr" | awk '{print $4}');
_msr_l="$(( _msr_l >> 24 & 0xFF )) $(( _msr_l >> 16 & 0xFF )) $(( _msr_l >> 8 & 0xFF )) $(( _msr_l & 0xFF ))"
read_msr_value="$_msr_h $_msr_l"
else
# for Linux
# convert to decimal
_msr=$(( _msr ))
if [ ! -r /dev/cpu/"$_cpu"/msr ]; then
return 200 # permission error
# if rdmsr is available, use it
elif which rdmsr >/dev/null 2>&1 && [ "$SMC_NO_RDMSR" != 1 ]; then
_debug "read_msr: using rdmsr"
read_msr_value=$(rdmsr -r $_msr 2>/dev/null | od -t u8 -A n)
# or if we have perl, use it, any 5.x version will work
elif which perl >/dev/null 2>&1 && [ "$SMC_NO_PERL" != 1 ]; then
_debug "read_msr: using perl"
read_msr_value=$(perl -e "open(M,'<','/dev/cpu/$_cpu/msr') and seek(M,$_msr,0) and read(M,\$_,8) and print" | od -t u8 -A n)
# fallback to dd if it supports skip_bytes
elif dd if=/dev/null of=/dev/null bs=8 count=1 skip="$_msr" iflag=skip_bytes 2>/dev/null; then
_debug "read_msr: using dd"
read_msr_value=$(dd if=/dev/cpu/"$_cpu"/msr bs=8 count=1 skip="$_msr" iflag=skip_bytes 2>/dev/null | od -t u8 -A n)
else
_debug "read_msr: got no rdmsr, perl or recent enough dd!"
return 201 # missing tool error
fi
if [ -z "$read_msr_value" ]; then
# MSR doesn't exist, don't check for $? because some versions of dd still return 0!
return 1
fi
fi
_debug "read_msr: MSR=$1 value is $read_msr_value"
return 0
}
check_cpu()
{
_info "\033[1;34mHardware check\033[0m"
if ! uname -m | grep -qwE 'x86_64|i[3-6]86|amd64'; then
return
fi
_info "* Hardware support (CPU microcode) for mitigation techniques"
_info " * Indirect Branch Restricted Speculation (IBRS)"
_info_nol " * SPEC_CTRL MSR is available: "
number_of_cpus
ncpus=$?
idx_max_cpu=$((ncpus-1))
if [ ! -e /dev/cpu/0/msr ] && [ ! -e /dev/cpuctl0 ]; 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 ] && [ ! -e /dev/cpuctl0 ]; then
spec_ctrl_msr=-1
pstatus yellow UNKNOWN "is msr kernel module available?"
else
# the new MSR 'SPEC_CTRL' is at offset 0x48
# we check if we have it for all cpus
val=0
cpu_mismatch=0
for i in $(seq 0 "$idx_max_cpu")
do
read_msr 0x48 "$i"; ret=$?
if [ "$i" -eq 0 ]; then
val=$ret
else
if [ "$ret" -eq $val ]; then
continue
else
cpu_mismatch=1
fi
fi
done
if [ $val -eq 0 ]; then
if [ $cpu_mismatch -eq 0 ]; then
spec_ctrl_msr=1
pstatus green YES
else
spec_ctrl_msr=1
pstatus green YES "But not in all CPUs"
fi
elif [ $val -eq 200 ]; then
pstatus yellow UNKNOWN "is msr kernel module available?"
spec_ctrl_msr=-1
elif [ $val -eq 201 ]; then
pstatus yellow UNKNOWN "missing tool, install either msr-tools or perl"
spec_ctrl_msr=-1
else
spec_ctrl_msr=0
pstatus yellow NO
fi
fi
_info_nol " * CPU indicates IBRS capability: "
# from kernel src: { X86_FEATURE_SPEC_CTRL, CPUID_EDX,26, 0x00000007, 0 },
# amd: https://developer.amd.com/wp-content/resources/Architecture_Guidelines_Update_Indirect_Branch_Control.pdf
# amd: 8000_0008 EBX[14]=1
if is_intel; then
read_cpuid 0x7 $EDX 26 1 1; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES "SPEC_CTRL feature bit"
cpuid_spec_ctrl=1
cpuid_ibrs='SPEC_CTRL'
fi
elif is_amd; then
read_cpuid 0x80000008 $EBX 14 1 1; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES "IBRS_SUPPORT feature bit"
cpuid_ibrs='IBRS_SUPPORT'
fi
else
ret=-1
pstatus yellow UNKNOWN "unknown CPU"
fi
if [ $ret -eq 1 ]; then
pstatus yellow NO
elif [ $ret -eq 2 ]; then
pstatus yellow UNKNOWN "is cpuid kernel module available?"
cpuid_spec_ctrl=-1
fi
if is_amd; then
_info_nol " * CPU indicates preferring IBRS always-on: "
# amd
read_cpuid 0x80000008 $EBX 16 1 1; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES
else
pstatus yellow NO
fi
_info_nol " * CPU indicates preferring IBRS over retpoline: "
# amd
read_cpuid 0x80000008 $EBX 18 1 1; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES
else
pstatus yellow NO
fi
fi
# IBPB
_info " * Indirect Branch Prediction Barrier (IBPB)"
_info_nol " * PRED_CMD MSR is available: "
if [ ! -e /dev/cpu/0/msr ] && [ ! -e /dev/cpuctl0 ]; then
pstatus yellow UNKNOWN "is msr kernel module available?"
else
# the new MSR 'PRED_CTRL' is at offset 0x49, write-only
# we test if of all cpus
val=0
cpu_mismatch=0
for i in $(seq 0 "$idx_max_cpu")
do
write_msr 0x49 "$i"; ret=$?
if [ "$i" -eq 0 ]; then
val=$ret
else
if [ "$ret" -eq $val ]; then
continue
else
cpu_mismatch=1
fi
fi
done
if [ $val -eq 0 ]; then
if [ $cpu_mismatch -eq 0 ]; then
pstatus green YES
else
pstatus green YES "But not in all CPUs"
fi
elif [ $val -eq 200 ]; then
pstatus yellow UNKNOWN "is msr kernel module available?"
else
pstatus yellow NO
fi
fi
_info_nol " * CPU indicates IBPB capability: "
# CPUID EAX=0x80000008, ECX=0x00 return EBX[12] indicates support for just IBPB.
if [ "$cpuid_spec_ctrl" = 1 ]; then
# spec_ctrl implies ibpb
cpuid_ibpb='SPEC_CTRL'
pstatus green YES "SPEC_CTRL feature bit"
elif is_intel; then
if [ "$cpuid_spec_ctrl" = -1 ]; then
pstatus yellow UNKNOWN "is cpuid kernel module available?"
else
pstatus yellow NO
fi
elif is_amd; then
read_cpuid 0x80000008 $EBX 12 1 1; ret=$?
if [ $ret -eq 0 ]; then
cpuid_ibpb='IBPB_SUPPORT'
pstatus green YES "IBPB_SUPPORT feature bit"
elif [ $ret -eq 1 ]; then
pstatus yellow NO
else
pstatus yellow UNKNOWN "is cpuid kernel module available?"
fi
fi
# STIBP
_info " * Single Thread Indirect Branch Predictors (STIBP)"
_info_nol " * SPEC_CTRL MSR is available: "
if [ "$spec_ctrl_msr" = 1 ]; then
pstatus green YES
elif [ "$spec_ctrl_msr" = 0 ]; then
pstatus yellow NO
else
pstatus yellow UNKNOWN "is msr kernel module available?"
fi
_info_nol " * CPU indicates STIBP capability: "
# intel: A processor supports STIBP if it enumerates CPUID (EAX=7H,ECX=0):EDX[27] as 1
# amd: 8000_0008 EBX[15]=1
if is_intel; then
read_cpuid 0x7 $EDX 27 1 1; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES "Intel STIBP feature bit"
#cpuid_stibp='Intel STIBP'
fi
elif is_amd; then
read_cpuid 0x80000008 $EBX 15 1 1; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES "AMD STIBP feature bit"
#cpuid_stibp='AMD STIBP'
fi
else
ret=-1
pstatus yellow UNKNOWN "unknown CPU"
fi
if [ $ret -eq 1 ]; then
pstatus yellow NO
elif [ $ret -eq 2 ]; then
pstatus yellow UNKNOWN "is cpuid kernel module available?"
fi
if is_amd; then
_info_nol " * CPU indicates preferring STIBP always-on: "
read_cpuid 0x80000008 $EBX 17 1 1; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES
else
pstatus yellow NO
fi
fi
# variant 4
if is_intel; then
_info " * Speculative Store Bypass Disable (SSBD)"
_info_nol " * CPU indicates SSBD capability: "
read_cpuid 0x7 $EDX 31 1 1; ret=$?
if [ $ret -eq 0 ]; then
cpuid_ssbd='Intel SSBD'
fi
elif is_amd; then
_info " * Speculative Store Bypass Disable (SSBD)"
_info_nol " * CPU indicates SSBD capability: "
read_cpuid 0x80000008 $EBX 24 1 1; ret24=$?
read_cpuid 0x80000008 $EBX 25 1 1; ret25=$?
if [ $ret24 -eq 0 ]; then
cpuid_ssbd='AMD SSBD in SPEC_CTRL'
#cpuid_ssbd_spec_ctrl=1
elif [ $ret25 -eq 0 ]; then
cpuid_ssbd='AMD SSBD in VIRT_SPEC_CTRL'
#cpuid_ssbd_virt_spec_ctrl=1
elif [ "$cpu_family" -ge 21 ] && [ "$cpu_family" -le 23 ]; then
cpuid_ssbd='AMD non-architectural MSR'
fi
fi
if [ -n "$cpuid_ssbd" ]; then
pstatus green YES "$cpuid_ssbd"
elif [ "$ret24" = 2 ] && [ "$ret25" = 2 ]; then
pstatus yellow UNKNOWN "is cpuid kernel module available?"
else
pstatus yellow NO
fi
if is_amd; then
# similar to SSB_NO for intel
read_cpuid 0x80000008 $EBX 26 1 1; ret=$?
if [ $ret -eq 0 ]; then
amd_ssb_no=1
fi
fi
_info " * L1 data cache invalidation"
_info_nol " * FLUSH_CMD MSR is available: "
if [ ! -e /dev/cpu/0/msr ] && [ ! -e /dev/cpuctl0 ]; then
pstatus yellow UNKNOWN "is msr kernel module available?"
else
# the new MSR 'FLUSH_CMD' is at offset 0x10b, write-only
# we test if of all cpus
val=0
cpu_mismatch=0
for i in $(seq 0 "$idx_max_cpu")
do
write_msr 0x10b "$i"; ret=$?
if [ "$i" -eq 0 ]; then
val=$ret
else
if [ "$ret" -eq $val ]; then
continue
else
cpu_mismatch=1
fi
fi
done
if [ $val -eq 0 ]; then
if [ $cpu_mismatch -eq 0 ]; then
pstatus green YES
cpu_flush_cmd=1
else
pstatus green YES "But not in all CPUs"
fi
elif [ $val -eq 200 ]; then
pstatus yellow UNKNOWN "is msr kernel module available?"
else
pstatus yellow NO
fi
fi
if is_intel; then
_info " * Enhanced IBRS (IBRS_ALL)"
_info_nol " * CPU indicates ARCH_CAPABILITIES MSR availability: "
cpuid_arch_capabilities=-1
# A processor supports the ARCH_CAPABILITIES MSR if it enumerates CPUID (EAX=7H,ECX=0):EDX[29] as 1
read_cpuid 0x7 $EDX 29 1 1; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES
cpuid_arch_capabilities=1
elif [ $ret -eq 2 ]; then
pstatus yellow UNKNOWN "is cpuid kernel module available?"
else
pstatus yellow NO
cpuid_arch_capabilities=0
fi
_info_nol " * ARCH_CAPABILITIES MSR advertises IBRS_ALL capability: "
capabilities_rdcl_no=-1
capabilities_ibrs_all=-1
capabilities_ssb_no=-1
capabilities_rsba=-1
if [ "$cpuid_arch_capabilities" = -1 ]; then
pstatus yellow UNKNOWN
elif [ "$cpuid_arch_capabilities" != 1 ]; then
capabilities_rdcl_no=0
capabilities_ibrs_all=0
capabilities_ssb_no=0
capabilities_rsba=0
pstatus yellow NO
elif [ ! -e /dev/cpu/0/msr ] && [ ! -e /dev/cpuctl0 ]; then
spec_ctrl_msr=-1
pstatus yellow UNKNOWN "is msr kernel module available?"
else
# the new MSR 'ARCH_CAPABILITIES' is at offset 0x10a
# we check if we have it for all cpus
val=0
val_cap_msr=0
cpu_mismatch=0
for i in $(seq 0 "$idx_max_cpu")
do
read_msr 0x10a "$i"; ret=$?
capabilities=$read_msr_value
if [ "$i" -eq 0 ]; then
val=$ret
val_cap_msr=$capabilities
else
if [ "$ret" -eq "$val" ] && [ "$capabilities" -eq "$val_cap_msr" ]; then
continue
else
cpu_mismatch=1
fi
fi
done
capabilities=$val_cap_msr
capabilities_rdcl_no=0
capabilities_ibrs_all=0
capabilities_ssb_no=0
capabilities_rsba=0
if [ $val -eq 0 ]; then
_debug "capabilities MSR is $capabilities (decimal)"
[ $(( capabilities >> 0 & 1 )) -eq 1 ] && capabilities_rdcl_no=1
[ $(( capabilities >> 1 & 1 )) -eq 1 ] && capabilities_ibrs_all=1
[ $(( capabilities >> 2 & 1 )) -eq 1 ] && capabilities_rsba=1
[ $(( capabilities >> 4 & 1 )) -eq 1 ] && capabilities_ssb_no=1
_debug "capabilities says rdcl_no=$capabilities_rdcl_no ibrs_all=$capabilities_ibrs_all ssb_no=$capabilities_ssb_no rsba=$capabilities_rsba"
if [ "$capabilities_ibrs_all" = 1 ]; then
if [ $cpu_mismatch -eq 0 ]; then
pstatus green YES
else
pstatus green YES "But not in all CPUs"
fi
else
pstatus yellow NO
fi
elif [ $val -eq 200 ]; then
pstatus yellow UNKNOWN "is msr kernel module available?"
elif [ $val -eq 201 ]; then
pstatus yellow UNKNOWN "missing tool, install either msr-tools or perl"
else
pstatus yellow NO
fi
fi
_info_nol " * CPU explicitly indicates not being vulnerable to Meltdown (RDCL_NO): "
if [ "$capabilities_rdcl_no" = -1 ]; then
pstatus yellow UNKNOWN
elif [ "$capabilities_rdcl_no" = 1 ]; then
pstatus green YES
else
pstatus yellow NO
fi
fi
_info_nol " * CPU explicitly indicates not being vulnerable to Variant 4 (SSB_NO): "
if [ "$capabilities_ssb_no" = -1 ]; then
pstatus yellow UNKNOWN
elif [ "$capabilities_ssb_no" = 1 ] || [ "$amd_ssb_no" = 1 ]; then
pstatus green YES
else
pstatus yellow NO
fi
_info_nol " * Hypervisor indicates host CPU might be vulnerable to RSB underflow (RSBA): "
if [ "$capabilities_rsba" = -1 ]; then
pstatus yellow UNKNOWN
elif [ "$capabilities_rsba" = 1 ]; then
pstatus yellow YES
else
pstatus blue NO
fi
_info_nol " * CPU supports Software Guard Extensions (SGX): "
ret=1
cpuid_sgx=0
if is_intel; then
read_cpuid 0x7 $EBX 2 1 1; ret=$?
fi
if [ $ret -eq 0 ]; then
pstatus blue YES
cpuid_sgx=1
elif [ $ret -eq 2 ]; then
pstatus yellow UNKNOWN "is cpuid kernel module available?"
cpuid_sgx=-1
else
pstatus green NO
fi
_info_nol " * CPU microcode is known to cause stability problems: "
if is_ucode_blacklisted; then
pstatus red YES "$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 blue NO "$ucode_found"
fi
_info_nol " * CPU microcode is the latest known available version: "
is_latest_known_ucode; ret=$?
if [ $ret -eq 0 ]; then
pstatus green YES "$ucode_latest"
elif [ $ret -eq 1 ]; then
pstatus red NO "$ucode_latest"
else
pstatus blue UNKNOWN "$ucode_latest"
fi
}
check_cpu_vulnerabilities()
{
_info "* CPU vulnerability to the speculative execution attack variants"
for cve in $supported_cve_list; do
_info_nol " * Vulnerable to $cve ($(cve2name "$cve")): "
if is_cpu_vulnerable "$cve"; then
pstatus yellow YES
else
pstatus green NO
fi
done
}
check_redhat_canonical_spectre()
{
# if we were already called, don't do it again
[ -n "$redhat_canonical_spectre" ] && return
if ! which "${opt_arch_prefix}strings" >/dev/null 2>&1; then
redhat_canonical_spectre=-1
elif [ -n "$kernel_err" ]; then
redhat_canonical_spectre=-2
else
# Red Hat / Ubuntu specific variant1 patch is difficult to detect,
# let's use the two same tricks than the official Red Hat detection script uses:
if "${opt_arch_prefix}strings" "$kernel" | grep -qw noibrs && "${opt_arch_prefix}strings" "$kernel" | grep -qw noibpb; then
# 1) detect their specific variant2 patch. If it's present, it means
# that the variant1 patch is also present (both were merged at the same time)
_debug "found redhat/canonical version of the variant2 patch (implies variant1)"
redhat_canonical_spectre=1
elif "${opt_arch_prefix}strings" "$kernel" | grep -q 'x86/pti:'; then
# 2) detect their specific variant3 patch. If it's present, but the variant2
# is not, it means that only variant1 is present in addition to variant3
_debug "found redhat/canonical version of the variant3 patch (implies variant1 but not variant2)"
redhat_canonical_spectre=2
else
redhat_canonical_spectre=0
fi
fi
}
###################
# SPECTRE 1 SECTION
# bounds check bypass aka 'Spectre Variant 1'
check_CVE_2017_5753()
{
cve='CVE-2017-5753'
_info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m"
if [ "$os" = Linux ]; then
check_CVE_2017_5753_linux
elif echo "$os" | grep -q BSD; then
check_CVE_2017_5753_bsd
else
_warn "Unsupported OS ($os)"
fi
}
check_CVE_2017_5753_linux()
{
status=UNK
sys_interface_available=0
msg=''
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/spectre_v1"; then
# this kernel has the /sys interface, trust it over everything
# v0.33+: don't. some kernels have backported the array_index_mask_nospec() workaround without
# modifying the vulnerabilities/spectre_v1 file. that's bad. we can't trust it when it says Vulnerable :(
# see "silent backport" detection at the bottom of this func
sys_interface_available=1
fi
if [ "$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)
#
# arm32
##ifdef CONFIG_THUMB2_KERNEL
##define CSDB ".inst.w 0xf3af8014"
##else
##define CSDB ".inst 0xe320f014" e320f014
##endif
#asm volatile(
# "cmp %1, %2\n" e1500003
#" sbc %0, %1, %1\n" e0c03000
#CSDB
#: "=r" (mask)
#: "r" (idx), "Ir" (sz)
#: "cc");
#
# http://git.arm.linux.org.uk/cgit/linux-arm.git/commit/?h=spectre&id=a78d156587931a2c3b354534aa772febf6c9e855
if [ -n "$kernel_err" ]; then
pstatus yellow UNKNOWN "couldn't check ($kernel_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) }' "$kernel"; ret=$?
if [ $ret -gt 0 ]; then
pstatus green YES "$ret occurrence(s) found of x86 64 bits array_index_mask_nospec()"
v1_mask_nospec="x86 64 bits array_index_mask_nospec"
else
perl -ne '/\x3b\x82..\x00\x00\x73.\x19\xd2\x21\xd0/ and $found++; END { exit($found) }' "$kernel"; ret=$?
if [ $ret -gt 0 ]; then
pstatus green YES "$ret occurrence(s) found of x86 32 bits array_index_mask_nospec()"
v1_mask_nospec="x86 32 bits array_index_mask_nospec"
else
ret=$("${opt_arch_prefix}objdump" -d "$kernel" | grep -w -e f3af8014 -e e320f014 -B2 | grep -B1 -w sbc | grep -w -c cmp)
if [ "$ret" -gt 0 ]; then
pstatus green YES "$ret occurrence(s) found of arm 32 bits array_index_mask_nospec()"
v1_mask_nospec="arm 32 bits array_index_mask_nospec"
else
pstatus yellow NO
fi
fi
fi
fi
_info_nol "* Kernel has the Red Hat/Ubuntu patch: "
check_redhat_canonical_spectre
if [ "$redhat_canonical_spectre" = -1 ]; then
pstatus yellow UNKNOWN "missing '${opt_arch_prefix}strings' tool, please install it, usually it's in the binutils package"
elif [ "$redhat_canonical_spectre" = -2 ]; then
pstatus yellow UNKNOWN "couldn't check ($kernel_err)"
elif [ "$redhat_canonical_spectre" = 1 ]; then
pstatus green YES
elif [ "$redhat_canonical_spectre" = 2 ]; then
pstatus green YES "but without IBRS"
else
pstatus yellow NO
fi
_info_nol "* Kernel has mask_nospec64 (arm64): "
#.macro mask_nospec64, idx, limit, tmp
#sub \tmp, \idx, \limit
#bic \tmp, \tmp, \idx
#and \idx, \idx, \tmp, asr #63
#csdb
#.endm
#$ aarch64-linux-gnu-objdump -d vmlinux | grep -w bic -A1 -B1 | grep -w sub -A2 | grep -w and -B2
#ffffff8008082e44: cb190353 sub x19, x26, x25
#ffffff8008082e48: 8a3a0273 bic x19, x19, x26
#ffffff8008082e4c: 8a93ff5a and x26, x26, x19, asr #63
#ffffff8008082e50: d503229f hint #0x14
# /!\ can also just be "csdb" instead of "hint #0x14" for native objdump
#
# if we have v1_mask_nospec or redhat_canonical_spectre>0, don't bother disassembling the kernel, the answer is no.
if [ -n "$v1_mask_nospec" ] || [ "$redhat_canonical_spectre" -gt 0 ]; then
pstatus yellow NO
elif [ -n "$kernel_err" ]; then
pstatus yellow UNKNOWN "couldn't check ($kernel_err)"
elif ! which perl >/dev/null 2>&1; then
pstatus yellow UNKNOWN "missing 'perl' binary, please install it"
elif ! which "${opt_arch_prefix}objdump" >/dev/null 2>&1; then
pstatus yellow UNKNOWN "missing '${opt_arch_prefix}objdump' tool, please install it, usually it's in the binutils package"
else
"${opt_arch_prefix}objdump" -d "$kernel" | perl -ne 'push @r, $_; /\s(hint|csdb)\s/ && $r[0]=~/\ssub\s+(x\d+)/ && $r[1]=~/\sbic\s+$1,\s+$1,/ && $r[2]=~/\sand\s/ && exit(9); shift @r if @r>3'; ret=$?
if [ "$ret" -eq 9 ]; then
pstatus green YES "mask_nospec64 macro is present and used"
v1_mask_nospec="arm64 mask_nospec64"
else
pstatus yellow NO
fi
fi
if [ "$opt_verbose" -ge 2 ] || ( [ -z "$v1_mask_nospec" ] && [ "$redhat_canonical_spectre" != 1 ] && [ "$redhat_canonical_spectre" != 2 ] ); then
# this is a slow heuristic and we don't need it if we already know the kernel is patched
# but still show it in verbose mode
_info_nol "* Checking count of LFENCE instructions following a jump in kernel... "
if [ -n "$kernel_err" ]; then
pstatus yellow UNKNOWN "couldn't check ($kernel_err)"
else
if ! which "${opt_arch_prefix}objdump" >/dev/null 2>&1; then
pstatus yellow UNKNOWN "missing '${opt_arch_prefix}objdump' tool, please install it, usually it's in the binutils package"
else
# here we disassemble the kernel and count the number of occurrences of the LFENCE opcode
# in non-patched kernels, this has been empirically determined as being around 40-50
# in patched kernels, this is more around 70-80, sometimes way higher (100+)
# v0.13: 68 found in a 3.10.23-xxxx-std-ipv6-64 (with lots of modules compiled-in directly), which doesn't have the LFENCE patches,
# so let's push the threshold to 70.
# v0.33+: now only count lfence opcodes after a jump, way less error-prone
# non patched kernel have between 0 and 20 matches, patched ones have at least 40-45
nb_lfence=$("${opt_arch_prefix}objdump" -d "$kernel" 2>/dev/null | grep -w -B1 lfence | grep -Ewc 'jmp|jne|je')
if [ "$nb_lfence" -lt 30 ]; then
pstatus yellow NO "only $nb_lfence jump-then-lfence instructions found, should be >= 30 (heuristic)"
else
v1_lfence=1
pstatus green YES "$nb_lfence jump-then-lfence instructions found, which is >= 30 (heuristic)"
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
if ! is_cpu_vulnerable "$cve"; 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 [ -n "$v1_mask_nospec" ]; then
pvulnstatus $cve OK "Kernel source has been patched to mitigate the vulnerability ($v1_mask_nospec)"
elif [ "$redhat_canonical_spectre" = 1 ] || [ "$redhat_canonical_spectre" = 2 ]; then
pvulnstatus $cve OK "Kernel source has been patched to mitigate the vulnerability (Red Hat/Ubuntu patch)"
elif [ "$v1_lfence" = 1 ]; then
pvulnstatus $cve OK "Kernel source has PROBABLY been patched to mitigate the vulnerability (jump-then-lfence instructions heuristic)"
elif [ "$kernel_err" ]; then
pvulnstatus $cve UNK "Couldn't find kernel image or tools missing to execute the checks"
explain "Re-run this script with root privileges, after installing the missing tools indicated above"
else
pvulnstatus $cve VULN "Kernel source needs to be patched to mitigate the vulnerability"
explain "Your kernel is too old to have the mitigation for Variant 1, you should upgrade to a newer kernel. If you're using a Linux distro and didn't compile the kernel yourself, you should upgrade your distro to get a newer kernel."
fi
else
if [ "$msg" = "Vulnerable" ] && [ -n "$v1_mask_nospec" ]; then
pvulnstatus $cve OK "Kernel source has been patched to mitigate the vulnerability (silent backport of array_index_mask_nospec)"
else
if [ "$msg" = "Vulnerable" ]; then
msg="Kernel source needs to be patched to mitigate the vulnerability"
_explain="Your kernel is too old to have the mitigation for Variant 1, you should upgrade to a newer kernel. If you're using a Linux distro and didn't compile the kernel yourself, you should upgrade your distro to get a newer kernel."
fi
pvulnstatus $cve "$status" "$msg"
[ -n "$_explain" ] && explain "$_explain"
unset _explain
fi
fi
}
check_CVE_2017_5753_bsd()
{
if ! is_cpu_vulnerable "$cve"; 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"
else
pvulnstatus $cve VULN "no mitigation for BSD yet"
fi
}
###################
# SPECTRE 2 SECTION
# branch target injection aka 'Spectre Variant 2'
check_CVE_2017_5715()
{
cve='CVE-2017-5715'
_info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m"
if [ "$os" = Linux ]; then
check_CVE_2017_5715_linux
elif echo "$os" | grep -q BSD; then
check_CVE_2017_5715_bsd
else
_warn "Unsupported OS ($os)"
fi
}
check_CVE_2017_5715_linux()
{
status=UNK
sys_interface_available=0
msg=''
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/spectre_v2"; then
# this kernel has the /sys interface, trust it over everything
sys_interface_available=1
fi
if [ "$opt_sysfs_only" != 1 ]; then
_info "* Mitigation 1"
ibrs_can_tell=0
ibrs_supported=''
ibrs_enabled=''
ibpb_can_tell=0
ibpb_supported=''
ibpb_enabled=''
if [ "$opt_live" = 1 ]; then
# in live mode, we can check for the ibrs_enabled file in debugfs
# all versions of the patches have it (NOT the case of IBPB or KPTI)
ibrs_can_tell=1
mount_debugfs
for dir in \
/sys/kernel/debug \
/sys/kernel/debug/x86 \
/proc/sys/kernel; do
if [ -e "$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: Red Hat (see https://access.redhat.com/articles/3311301)
# /proc/sys/kernel/ibrs_enabled: OpenSUSE tumbleweed
specex_knob_dir=$dir
ibrs_supported="$dir/ibrs_enabled exists"
ibrs_enabled=$(cat "$dir/ibrs_enabled" 2>/dev/null)
_debug "ibrs: found $dir/ibrs_enabled=$ibrs_enabled"
# if ibrs_enabled is there, ibpb_enabled will be in the same dir
if [ -e "$dir/ibpb_enabled" ]; then
# if the file is there, we have IBPB compiled-in (see note above for IBRS)
ibpb_supported="$dir/ibpb_enabled exists"
ibpb_enabled=$(cat "$dir/ibpb_enabled" 2>/dev/null)
_debug "ibpb: found $dir/ibpb_enabled=$ibpb_enabled"
else
_debug "ibpb: $dir/ibpb_enabled file doesn't exist"
fi
break
else
_debug "ibrs: $dir/ibrs_enabled file doesn't exist"
fi
done
# on some newer kernels, the spec_ctrl_ibrs flag in "$procfs/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 [ -z "$ibrs_supported" ]; then
if grep ^flags "$procfs/cpuinfo" | grep -qw spec_ctrl_ibrs; then
_debug "ibrs: found spec_ctrl_ibrs flag in $procfs/cpuinfo"
ibrs_supported="spec_ctrl_ibrs flag in $procfs/cpuinfo"
# enabled=2 -> kernel & user
ibrs_enabled=2
# XXX and what about ibpb ?
fi
fi
if [ -e "/sys/devices/system/cpu/vulnerabilities/spectre_v2" ]; then
# when IBPB is enabled on 4.15+, we can see it in sysfs
if grep -q 'IBPB' "/sys/devices/system/cpu/vulnerabilities/spectre_v2"; then
_debug "ibpb: found enabled in sysfs"
[ -z "$ibpb_supported" ] && ibpb_supported='IBPB found enabled in sysfs'
[ -z "$ibpb_enabled" ] && ibpb_enabled=1
fi
# when IBRS_FW is enabled on 4.15+, we can see it in sysfs
if grep -q ', IBRS_FW' "/sys/devices/system/cpu/vulnerabilities/spectre_v2"; then
_debug "ibrs: found IBRS_FW in sysfs"
[ -z "$ibrs_supported" ] && ibrs_supported='found IBRS_FW in sysfs'
ibrs_fw_enabled=1
fi
# when IBRS is enabled on 4.15+, we can see it in sysfs
if grep -q -e 'IBRS' -e 'Indirect Branch Restricted Speculation' "/sys/devices/system/cpu/vulnerabilities/spectre_v2"; then
_debug "ibrs: found IBRS in sysfs"
[ -z "$ibrs_supported" ] && ibrs_supported='found IBRS in sysfs'
[ -z "$ibrs_enabled" ] && ibrs_enabled=3
fi
fi
# in live mode, if ibrs or ibpb is supported and we didn't find these are enabled, then they are not
[ -n "$ibrs_supported" ] && [ -z "$ibrs_enabled" ] && ibrs_enabled=0
[ -n "$ibpb_supported" ] && [ -z "$ibpb_enabled" ] && ibpb_enabled=0
fi
if [ -z "$ibrs_supported" ]; then
check_redhat_canonical_spectre
if [ "$redhat_canonical_spectre" = 1 ]; then
ibrs_supported="Red Hat/Ubuntu variant"
ibpb_supported="Red Hat/Ubuntu variant"
fi
fi
if [ -z "$ibrs_supported" ] && [ -n "$kernel" ]; then
if ! which "${opt_arch_prefix}strings" >/dev/null 2>&1; then
:
else
ibrs_can_tell=1
ibrs_supported=$("${opt_arch_prefix}strings" "$kernel" | grep -Fw -e ', IBRS_FW' | head -1)
if [ -n "$ibrs_supported" ]; then
_debug "ibrs: found ibrs evidence in kernel image ($ibrs_supported)"
ibrs_supported="found '$ibrs_supported' in kernel image"
fi
fi
fi
if [ -z "$ibrs_supported" ] && [ -n "$opt_map" ]; then
ibrs_can_tell=1
if grep -q spec_ctrl "$opt_map"; then
ibrs_supported="found spec_ctrl in symbols file"
_debug "ibrs: found '*spec_ctrl*' symbol in $opt_map"
fi
fi
# recent (4.15) vanilla kernels have IBPB but not IBRS, and without the debugfs tunables of Red Hat
# we can detect it directly in the image
if [ -z "$ibpb_supported" ] && [ -n "$kernel" ]; then
if ! which "${opt_arch_prefix}strings" >/dev/null 2>&1; then
:
else
ibpb_can_tell=1
ibpb_supported=$("${opt_arch_prefix}strings" "$kernel" | grep -Fw -e 'ibpb' -e ', IBPB' | head -1)
if [ -n "$ibpb_supported" ]; then
_debug "ibpb: found ibpb evidence in kernel image ($ibpb_supported)"
ibpb_supported="found '$ibpb_supported' in kernel image"
fi
fi
fi
_info_nol " * Kernel is compiled with IBRS support: "
if [ -z "$ibrs_supported" ]; then
if [ "$ibrs_can_tell" = 1 ]; then
pstatus yellow NO
else
# if we're in offline mode without System.map, we can't really know
pstatus yellow UNKNOWN "in offline mode, we need the kernel image and System.map to be able to tell"
fi
else
if [ "$opt_verbose" -ge 2 ]; then
pstatus green YES "$ibrs_supported"
else
pstatus green YES
fi
fi
_info_nol " * IBRS enabled and active: "
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
# 3 is enabled
case "$ibrs_enabled" in
0)
if [ "$ibrs_fw_enabled" = 1 ]; then
pstatus blue YES "for firmware code only"
else
pstatus yellow NO
fi
;;
1) if [ "$ibrs_fw_enabled" = 1 ]; then pstatus green YES "for kernel space and firmware code"; else pstatus green YES "for kernel space"; fi;;
2) if [ "$ibrs_fw_enabled" = 1 ]; then pstatus green YES "for kernel, user space, and firmware code" ; else pstatus green YES "for both kernel and user space"; fi;;
3) if [ "$ibrs_fw_enabled" = 1 ]; then pstatus green YES "for kernel and firmware code"; else pstatus green YES; fi;;
*) if [ "$cpuid_ibrs" != 'SPEC_CTRL' ] && [ "$cpuid_ibrs" != 'IBRS_SUPPORT' ] && [ "$cpuid_spec_ctrl" != -1 ];
then pstatus yellow NO; _debug "ibrs: known cpu not supporting SPEC-CTRL or IBRS";
else
pstatus yellow UNKNOWN; fi;;
esac
fi
else
pstatus blue N/A "not testable in offline mode"
fi
_info_nol " * Kernel is compiled with IBPB support: "
if [ -z "$ibpb_supported" ]; then
if [ "$ibpb_can_tell" = 1 ]; then
pstatus yellow NO
else
# if we're in offline mode without System.map, we can't really know
pstatus yellow UNKNOWN "in offline mode, we need the kernel image to be able to tell"
fi
else
if [ "$opt_verbose" -ge 2 ]; then
pstatus green YES "$ibpb_supported"
else
pstatus green YES
fi
fi
_info_nol " * IBPB enabled and active: "
if [ "$opt_live" = 1 ]; then
case "$ibpb_enabled" in
"")
if [ "$ibrs_supported" = 1 ]; then
pstatus yellow UNKNOWN
else
pstatus yellow NO
fi
;;
0)
pstatus yellow NO
;;
1) pstatus green YES;;
2) pstatus green YES "IBPB used instead of IBRS in all kernel entrypoints";;
*) pstatus yellow UNKNOWN;;
esac
else
pstatus blue N/A "not testable in offline mode"
fi
_info "* Mitigation 2"
_info_nol " * Kernel has branch predictor hardening (arm): "
if [ -r "$opt_config" ]; then
bp_harden_can_tell=1
bp_harden=$(grep -w 'CONFIG_HARDEN_BRANCH_PREDICTOR=y' "$opt_config")
if [ -n "$bp_harden" ]; then
pstatus green YES
_debug "bp_harden: found '$bp_harden' in $opt_config"
fi
fi
if [ -z "$bp_harden" ] && [ -n "$opt_map" ]; then
bp_harden_can_tell=1
bp_harden=$(grep -w bp_hardening_data "$opt_map")
if [ -n "$bp_harden" ]; then
pstatus green YES
_debug "bp_harden: found '$bp_harden' in $opt_map"
fi
fi
if [ -z "$bp_harden" ]; then
if [ "$bp_harden_can_tell" = 1 ]; then
pstatus yellow NO
else
pstatus yellow UNKNOWN
fi
fi
_info_nol " * Kernel compiled with retpoline option: "
# We check the RETPOLINE kernel options
if [ -r "$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 $opt_config"
else
pstatus yellow NO
fi
else
pstatus yellow UNKNOWN "couldn't read your kernel configuration"
fi
if [ "$retpoline" = 1 ]; then
# 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 there is "retpoline" in the file and NOT "minimal", then it's full retpoline
# (works for vanilla and Red Hat variants)
if [ "$opt_live" = 1 ] && [ -e "/sys/devices/system/cpu/vulnerabilities/spectre_v2" ]; then
if grep -qwi retpoline /sys/devices/system/cpu/vulnerabilities/spectre_v2; then
if grep -qwi minimal /sys/devices/system/cpu/vulnerabilities/spectre_v2; then
retpoline_compiler=0
retpoline_compiler_reason="kernel reports minimal retpoline compilation"
else
retpoline_compiler=1
retpoline_compiler_reason="kernel reports full retpoline compilation"
fi
fi
elif [ -n "$opt_map" ]; then
# look for the symbol
if grep -qw noretpoline_setup "$opt_map"; then
retpoline_compiler=1
retpoline_compiler_reason="noretpoline_setup symbol found in System.map"
fi
elif [ -n "$kernel" ]; then
# look for the symbol
if which "${opt_arch_prefix}nm" >/dev/null 2>&1; then
# the proper way: use nm and look for the symbol
if "${opt_arch_prefix}nm" "$kernel" 2>/dev/null | grep -qw 'noretpoline_setup'; then
retpoline_compiler=1
retpoline_compiler_reason="noretpoline_setup found in kernel symbols"
fi
elif grep -q noretpoline_setup "$kernel"; 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
retpoline_compiler_reason="noretpoline_setup found in kernel"
fi
fi
if [ -n "$retpoline_compiler" ]; then
_info_nol " * Kernel compiled with a retpoline-aware compiler: "
if [ "$retpoline_compiler" = 1 ]; then
if [ -n "$retpoline_compiler_reason" ]; then
pstatus green YES "$retpoline_compiler_reason"
else
pstatus green YES
fi
else
if [ -n "$retpoline_compiler_reason" ]; then
pstatus red NO "$retpoline_compiler_reason"
else
pstatus red NO
fi
fi
fi
fi
# only Red Hat has a tunable to disable it on runtime
if [ "$opt_live" = 1 ]; then
if [ -e "$specex_knob_dir/retp_enabled" ]; then
retp_enabled=$(cat "$specex_knob_dir/retp_enabled" 2>/dev/null)
_debug "retpoline: found $specex_knob_dir/retp_enabled=$retp_enabled"
_info_nol " * Retpoline is enabled: "
if [ "$retp_enabled" = 1 ]; then
pstatus green YES
else
pstatus yellow NO
fi
fi
fi
# only for information, in verbose mode
if [ "$opt_verbose" -ge 2 ]; then
_info_nol " * Local gcc is retpoline-aware: "
if which gcc >/dev/null 2>&1; then
if [ -n "$(gcc -mindirect-branch=thunk-extern --version 2>&1 >/dev/null)" ]; then
pstatus blue NO
else
pstatus green YES
fi
else
pstatus blue NO "gcc is not installed"
fi
fi
if is_vulnerable_to_empty_rsb || [ "$opt_verbose" -ge 2 ]; then
_info_nol " * Kernel supports RSB filling: "
if ! which "${opt_arch_prefix}strings" >/dev/null 2>&1; then
pstatus yellow UNKNOWN "missing '${opt_arch_prefix}strings' tool, please install it, usually it's in the binutils package"
elif [ -z "$kernel" ]; then
pstatus yellow UNKNOWN "kernel image missing"
else
rsb_filling=$("${opt_arch_prefix}strings" "$kernel" | grep -w 'Filling RSB on context switch')
if [ -n "$rsb_filling" ]; then
pstatus green YES
else
pstatus yellow NO
fi
fi
fi
elif [ "$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
if ! is_cpu_vulnerable "$cve"; then
# override status & msg in case CPU is not vulnerable after all
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
else
if [ "$retpoline" = 1 ] && [ "$retpoline_compiler" = 1 ] && [ "$retp_enabled" != 0 ] && [ -n "$ibpb_enabled" ] && [ "$ibpb_enabled" -ge 1 ] && ( ! is_vulnerable_to_empty_rsb || [ -n "$rsb_filling" ] ); then
pvulnstatus $cve OK "Full retpoline + IBPB are mitigating the vulnerability"
elif [ "$retpoline" = 1 ] && [ "$retpoline_compiler" = 1 ] && [ "$retp_enabled" != 0 ] && [ "$opt_paranoid" = 0 ] && ( ! is_vulnerable_to_empty_rsb || [ -n "$rsb_filling" ] ); then
pvulnstatus $cve OK "Full retpoline is mitigating the vulnerability"
if [ -n "$cpuid_ibpb" ]; then
_warn "You should enable IBPB to complete retpoline as a Variant 2 mitigation"
else
_warn "IBPB is considered as a good addition to retpoline for Variant 2 mitigation, but your CPU microcode doesn't support it"
fi
elif [ -n "$ibrs_enabled" ] && [ -n "$ibpb_enabled" ] && [ "$ibrs_enabled" -ge 1 ] && [ "$ibpb_enabled" -ge 1 ]; then
pvulnstatus $cve OK "IBRS + IBPB are mitigating the vulnerability"
elif [ "$ibpb_enabled" = 2 ] && ! is_cpu_smt_enabled; then
pvulnstatus $cve OK "Full IBPB is mitigating the vulnerability"
elif [ -n "$bp_harden" ]; then
pvulnstatus $cve OK "Branch predictor hardening mitigates the vulnerability"
elif [ -z "$bp_harden" ] && [ "$cpu_vendor" = ARM ]; then
pvulnstatus $cve VULN "Branch predictor hardening is needed to mitigate the vulnerability"
explain "Your kernel has not been compiled with the CONFIG_UNMAP_KERNEL_AT_EL0 option, recompile it with this option enabled."
elif [ "$opt_live" != 1 ]; then
if [ "$retpoline" = 1 ] && [ -n "$ibpb_supported" ]; then
pvulnstatus $cve OK "offline mode: kernel supports retpoline + IBPB to mitigate the vulnerability"
elif [ -n "$ibrs_supported" ] && [ -n "$ibpb_supported" ]; then
pvulnstatus $cve OK "offline mode: kernel supports IBRS + IBPB to mitigate the vulnerability"
elif [ "$ibrs_can_tell" != 1 ]; then
pvulnstatus $cve UNK "offline mode: not enough information"
explain "Re-run this script with root privileges, and give it the kernel image (--kernel), the kernel configuration (--config) and the System.map file (--map) corresponding to the kernel you would like to inspect."
fi
fi
# if we arrive here and didn't already call pvulnstatus, then it's VULN, let's explain why
if [ "$pvulnstatus_last_cve" != "$cve" ]; then
# explain what's needed for this CPU
if is_vulnerable_to_empty_rsb; then
pvulnstatus $cve VULN "IBRS+IBPB or retpoline+IBPB+RSB filling, is needed to mitigate the vulnerability"
explain "To mitigate this vulnerability, you need either IBRS + IBPB, both requiring hardware support from your CPU microcode in addition to kernel support, or a kernel compiled with retpoline and IBPB, with retpoline requiring a retpoline-aware compiler (re-run this script with -v to know if your version of gcc is retpoline-aware) and IBPB requiring hardware support from your CPU microcode. You also need a recent-enough kernel that supports RSB filling if you plan to use retpoline. For Skylake+ CPUs, the IBRS + IBPB approach is generally preferred as it guarantees complete protection, and the performance impact is not as high as with older CPUs in comparison with retpoline. More information about how to enable the missing bits for those two possible mitigations on your system follow. You only need to take one of the two approaches."
elif is_zen_cpu; then
pvulnstatus $cve VULN "retpoline+IBPB is needed to mitigate the vulnerability"
explain "To mitigate this vulnerability, You need a kernel compiled with retpoline + IBPB support, with retpoline requiring a retpoline-aware compiler (re-run this script with -v to know if your version of gcc is retpoline-aware) and IBPB requiring hardware support from your CPU microcode."
elif is_intel || is_amd; then
pvulnstatus $cve VULN "IBRS+IBPB or retpoline+IBPB is needed to mitigate the vulnerability"
explain "To mitigate this vulnerability, you need either IBRS + IBPB, both requiring hardware support from your CPU microcode in addition to kernel support, or a kernel compiled with retpoline and IBPB, with retpoline requiring a retpoline-aware compiler (re-run this script with -v to know if your version of gcc is retpoline-aware) and IBPB requiring hardware support from your CPU microcode. The retpoline + IBPB approach is generally preferred as the performance impact is lower. More information about how to enable the missing bits for those two possible mitigations on your system follow. You only need to take one of the two approaches."
else
# in that case, we might want to trust sysfs if it's there
if [ -n "$msg" ]; then
[ "$msg" = Vulnerable ] && msg="no known mitigation exists for your CPU vendor ($cpu_vendor)"
pvulnstatus $cve $status "$msg"
else
pvulnstatus $cve VULN "no known mitigation exists for your CPU vendor ($cpu_vendor)"
fi
fi
fi
# if we are in live mode, we can check for a lot more stuff and explain further
if [ "$opt_live" = 1 ] && [ "$vulnstatus" != "OK" ]; then
_explain_hypervisor="An updated CPU microcode will have IBRS/IBPB capabilities indicated in the Hardware Check section above. If you're running under an hypervisor (KVM, Xen, VirtualBox, VMware, ...), the hypervisor needs to be up to date to be able to export the new host CPU flags to the guest. You can run this script on the host to check if the host CPU is IBRS/IBPB. If it is, and it doesn't show up in the guest, upgrade the hypervisor. You may need to reconfigure your VM to use a CPU model that has IBRS capability; in Libvirt, such CPUs are listed with an IBRS suffix."
# IBPB (amd & intel)
if ( [ -z "$ibpb_enabled" ] || [ "$ibpb_enabled" = 0 ] ) && ( is_intel || is_amd ); then
if [ -z "$cpuid_ibpb" ]; then
explain "The microcode of your CPU needs to be upgraded to be able to use IBPB. This is usually done at boot time by your kernel (the upgrade is not persistent across reboots which is why it's done at each boot). If you're using a distro, make sure you are up to date, as microcode updates are usually shipped alongside with the distro kernel. Availability of a microcode update for you CPU model depends on your CPU vendor. You can usually find out online if a microcode update is available for your CPU by searching for your CPUID (indicated in the Hardware Check section). $_explain_hypervisor"
fi
if [ -z "$ibpb_supported" ]; then
explain "Your kernel doesn't have IBPB support, so you need to either upgrade your kernel (if you're using a distro) or recompiling a more recent kernel."
fi
if [ -n "$cpuid_ibpb" ] && [ -n "$ibpb_supported" ]; then
if [ -e "$specex_knob_dir/ibpb_enabled" ]; then
# newer (April 2018) Red Hat kernels have ibpb_enabled as ro, and automatically enables it with retpoline
if [ ! -w "$specex_knob_dir/ibpb_enabled" ] && [ -e "$specex_knob_dir/retp_enabled" ]; then
explain "Both your CPU and your kernel have IBPB support, but it is currently disabled. You kernel should enable IBPB automatically if you enable retpoline. You may enable it with \`echo 1 > $specex_knob_dir/retp_enabled\`."
else
explain "Both your CPU and your kernel have IBPB support, but it is currently disabled. You may enable it with \`echo 1 > $specex_knob_dir/ibpb_enabled\`."
fi
else
explain "Both your CPU and your kernel have IBPB support, but it is currently disabled. You may enable it. Check in your distro's documentation on how to do this."
fi
fi
elif [ "$ibpb_enabled" = 2 ] && is_cpu_smt_enabled; then
explain "You have ibpb_enabled set to 2, but it only offers sufficient protection when simultaneous multi-threading (aka SMT or HyperThreading) is disabled. You should reboot your system with the kernel parameter \`nosmt\`."
fi
# /IBPB
# IBRS (amd & intel)
if ( [ -z "$ibrs_enabled" ] || [ "$ibrs_enabled" = 0 ] ) && ( is_intel || is_amd ); then
if [ -z "$cpuid_ibrs" ]; then
explain "The microcode of your CPU needs to be upgraded to be able to use IBRS. This is usually done at boot time by your kernel (the upgrade is not persistent across reboots which is why it's done at each boot). If you're using a distro, make sure you are up to date, as microcode updates are usually shipped alongside with the distro kernel. Availability of a microcode update for you CPU model depends on your CPU vendor. You can usually find out online if a microcode update is available for your CPU by searching for your CPUID (indicated in the Hardware Check section). $_explain_hypervisor"
fi
if [ -z "$ibrs_supported" ]; then
explain "Your kernel doesn't have IBRS support, so you need to either upgrade your kernel (if you're using a distro) or recompiling a more recent kernel."
fi
if [ -n "$cpuid_ibrs" ] && [ -n "$ibrs_supported" ]; then
if [ -e "$specex_knob_dir/ibrs_enabled" ]; then
explain "Both your CPU and your kernel have IBRS support, but it is currently disabled. You may enable it with \`echo 1 > $specex_knob_dir/ibrs_enabled\`."
else
explain "Both your CPU and your kernel have IBRS support, but it is currently disabled. You may enable it. Check in your distro's documentation on how to do this."
fi
fi
fi
# /IBRS
unset _explain_hypervisor
# RETPOLINE (amd & intel)
if is_amd || is_intel; then
if [ "$retpoline" = 0 ]; then
explain "Your kernel is not compiled with retpoline support, so you need to either upgrade your kernel (if you're using a distro) or recompile your kernel with the CONFIG_RETPOLINE option enabled. You also need to compile your kernel with a retpoline-aware compiler (re-run this script with -v to know if your version of gcc is retpoline-aware)."
elif [ "$retpoline" = 1 ] && [ "$retpoline_compiler" = 0 ]; then
explain "Your kernel is compiled with retpoline, but without a retpoline-aware compiler (re-run this script with -v to know if your version of gcc is retpoline-aware)."
elif [ "$retpoline" = 1 ] && [ "$retpoline_compiler" = 1 ] && [ "$retp_enabled" = 0 ]; then
explain "Your kernel has retpoline support and has been compiled with a retpoline-aware compiler, but retpoline is disabled. You should enable it with \`echo 1 > $specex_knob_dir/retp_enabled\`."
fi
fi
# /RETPOLINE
fi
fi
# sysfs msgs:
#1 "Vulnerable"
#2 "Vulnerable: Minimal generic ASM retpoline"
#2 "Vulnerable: Minimal AMD ASM retpoline"
# "Mitigation: Full generic retpoline"
# "Mitigation: Full AMD retpoline"
# $MITIGATION + ", IBPB"
# $MITIGATION + ", IBRS_FW"
#5 $MITIGATION + " - vulnerable module loaded"
# Red Hat only:
#2 "Vulnerable: Minimal ASM retpoline",
#3 "Vulnerable: Retpoline without IBPB",
#4 "Vulnerable: Retpoline on Skylake+",
#5 "Vulnerable: Retpoline with unsafe module(s)",
# "Mitigation: Full retpoline",
# "Mitigation: Full retpoline and IBRS (user space)",
# "Mitigation: IBRS (kernel)",
# "Mitigation: IBRS (kernel and user space)",
# "Mitigation: IBP disabled",
}
check_CVE_2017_5715_bsd()
{
_info "* Mitigation 1"
_info_nol " * Kernel supports IBRS: "
ibrs_disabled=$(sysctl -n hw.ibrs_disable 2>/dev/null)
if [ -z "$ibrs_disabled" ]; then
pstatus yellow NO
else
pstatus green YES
fi
_info_nol " * IBRS enabled and active: "
ibrs_active=$(sysctl -n hw.ibrs_active 2>/dev/null)
if [ "$ibrs_active" = 1 ]; then
pstatus green YES
else
pstatus yellow NO
fi
_info "* Mitigation 2"
_info_nol " * Kernel compiled with RETPOLINE: "
if [ -n "$kernel_err" ]; then
pstatus yellow UNKNOWN "couldn't check ($kernel_err)"
else
if ! which "${opt_arch_prefix}readelf" >/dev/null 2>&1; then
pstatus yellow UNKNOWN "missing '${opt_arch_prefix}readelf' tool, please install it, usually it's in the binutils package"
else
nb_thunks=$("${opt_arch_prefix}readelf" -s "$kernel" | grep -c -e __llvm_retpoline_ -e __llvm_external_retpoline_ -e __x86_indirect_thunk_)
if [ "$nb_thunks" -gt 0 ]; then
retpoline=1
pstatus green YES "found $nb_thunks thunk(s)"
else
pstatus yellow NO
fi
fi
fi
if ! is_cpu_vulnerable "$cve"; then
# override status & msg in case CPU is not vulnerable after all
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
elif [ "$retpoline" = 1 ]; then
pvulnstatus $cve OK "Retpoline mitigates the vulnerability"
elif [ "$ibrs_active" = 1 ]; then
pvulnstatus $cve OK "IBRS mitigates the vulnerability"
elif [ "$ibrs_disabled" = 0 ]; then
pvulnstatus $cve VULN "IBRS is supported by your kernel but your CPU microcode lacks support"
explain "The microcode of your CPU needs to be upgraded to be able to use IBRS. Availability of a microcode update for you CPU model depends on your CPU vendor. You can usually find out online if a microcode update is available for your CPU by searching for your CPUID (indicated in the Hardware Check section). To do a microcode update, you can search the ports for the \`cpupdate\` tool. Microcode updates done this way are not reboot-proof, so be sure to do it every time the system boots up."
elif [ "$ibrs_disabled" = 1 ]; then
pvulnstatus $cve VULN "IBRS is supported but administratively disabled on your system"
explain "To enable IBRS, use \`sysctl hw.ibrs_disable=0\`"
else
pvulnstatus $cve VULN "IBRS is needed to mitigate the vulnerability but your kernel is missing support"
explain "You need to either upgrade your kernel or recompile yourself a more recent version having IBRS support"
fi
}
##################
# MELTDOWN SECTION
# no security impact but give a hint to the user in verbose mode
# about PCID/INVPCID cpuid features that must be present to avoid
# too big a performance impact with PTI
# refs:
# https://marc.info/?t=151532047900001&r=1&w=2
# https://groups.google.com/forum/m/#!topic/mechanical-sympathy/L9mHTbeQLNU
pti_performance_check()
{
_info_nol " * Reduced performance impact of PTI: "
if [ -e "$procfs/cpuinfo" ] && grep ^flags "$procfs/cpuinfo" | grep -qw pcid; then
cpu_pcid=1
else
read_cpuid 0x1 $ECX 17 1 1; ret=$?
[ $ret -eq 0 ] && cpu_pcid=1
fi
if [ -e "$procfs/cpuinfo" ] && grep ^flags "$procfs/cpuinfo" | grep -qw invpcid; then
cpu_invpcid=1
else
read_cpuid 0x7 $EBX 10 1 1; ret=$?
[ $ret -eq 0 ] && cpu_invpcid=1
fi
if [ "$cpu_invpcid" = 1 ]; then
pstatus green YES 'CPU supports INVPCID, performance impact of PTI will be greatly reduced'
elif [ "$cpu_pcid" = 1 ]; then
pstatus green YES 'CPU supports PCID, performance impact of PTI will be reduced'
else
pstatus blue NO 'PCID/INVPCID not supported, performance impact of PTI will be significant'
fi
}
# rogue data cache load aka 'Meltdown' aka 'Variant 3'
check_CVE_2017_5754()
{
cve='CVE-2017-5754'
_info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m"
if [ "$os" = Linux ]; then
check_CVE_2017_5754_linux
elif echo "$os" | grep -q BSD; then
check_CVE_2017_5754_bsd
else
_warn "Unsupported OS ($os)"
fi
}
check_CVE_2017_5754_linux()
{
status=UNK
sys_interface_available=0
msg=''
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/meltdown"; then
# this kernel has the /sys interface, trust it over everything
sys_interface_available=1
fi
if [ "$opt_sysfs_only" != 1 ]; then
_info_nol "* Kernel supports Page Table Isolation (PTI): "
kpti_support=''
kpti_can_tell=0
if [ -n "$opt_config" ]; then
kpti_can_tell=1
kpti_support=$(grep -w -e CONFIG_PAGE_TABLE_ISOLATION=y -e CONFIG_KAISER=y -e CONFIG_UNMAP_KERNEL_AT_EL0=y "$opt_config")
if [ -n "$kpti_support" ]; then
_debug "kpti_support: found option '$kpti_support' in $opt_config"
fi
fi
if [ -z "$kpti_support" ] && [ -n "$opt_map" ]; then
# it's not an elif: some backports don't have the PTI config but still include the patch
# so we try to find an exported symbol that is part of the PTI patch in System.map
# parse_kpti: arm
kpti_can_tell=1
kpti_support=$(grep -w -e kpti_force_enabled -e parse_kpti "$opt_map")
if [ -n "$kpti_support" ]; then
_debug "kpti_support: found '$kpti_support' in $opt_map"
fi
fi
if [ -z "$kpti_support" ] && [ -n "$kernel" ]; then
# same as above but in case we don't have System.map and only kernel, look for the
# nopti option that is part of the patch (kernel command line option)
# 'kpti=': arm
kpti_can_tell=1
if ! which "${opt_arch_prefix}strings" >/dev/null 2>&1; then
pstatus yellow UNKNOWN "missing '${opt_arch_prefix}strings' tool, please install it, usually it's in the binutils package"
else
kpti_support=$("${opt_arch_prefix}strings" "$kernel" | grep -w -e nopti -e kpti=)
if [ -n "$kpti_support" ]; then
_debug "kpti_support: found '$kpti_support' in $kernel"
fi
fi
fi
if [ -n "$kpti_support" ]; then
if [ "$opt_verbose" -ge 2 ]; then
pstatus green YES "found '$kpti_support'"
else
pstatus green YES
fi
elif [ "$kpti_can_tell" = 1 ]; then
pstatus yellow NO
else
pstatus yellow UNKNOWN "couldn't read your kernel configuration nor System.map file"
fi
mount_debugfs
_info_nol " * PTI enabled and active: "
if [ "$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 "$procfs/cpuinfo" | grep -qw pti; then
# vanilla PTI patch sets the 'pti' flag in cpuinfo
_debug "kpti_enabled: found 'pti' flag in $procfs/cpuinfo"
kpti_enabled=1
elif grep ^flags "$procfs/cpuinfo" | grep -qw kaiser; then
# kernel line 4.9 sets the 'kaiser' flag in cpuinfo
_debug "kpti_enabled: found 'kaiser' flag in $procfs/cpuinfo"
kpti_enabled=1
elif [ -e /sys/kernel/debug/x86/pti_enabled ]; then
# Red Hat Backport creates a dedicated file, see https://access.redhat.com/articles/3311301
kpti_enabled=$(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 yellow NO
fi
else
pstatus blue N/A "not testable in offline mode"
fi
pti_performance_check
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 [ $ret -eq 0 ]; then
if [ -e /proc/xen/capabilities ] && grep -q "control_d" /proc/xen/capabilities; then
xen_pv_domo=1
else
xen_pv_domu=1
fi
# PVHVM guests also print 'Booting paravirtualized kernel', so we need this check.
dmesg_grep 'Xen HVM callback vector for event delivery is enabled$'; ret=$?
if [ $ret -eq 0 ]; then
xen_pv_domu=0
fi
fi
fi
if [ "$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 [ "$xen_pv_domu" = 1 ]; then
pstatus yellow YES
else
pstatus blue NO
fi
fi
if ! is_cpu_vulnerable "$cve"; 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 $cve VULN "Xen PV DomUs are vulnerable and need to be run in HVM, PVHVM, PVH mode, or the Xen hypervisor must have the Xen's own PTI patch"
explain "Go to https://blog.xenproject.org/2018/01/22/xen-project-spectre-meltdown-faq-jan-22-update/ for more information"
elif [ "$kpti_enabled" = -1 ]; then
pvulnstatus $cve UNK "couldn't find any clue of PTI activation due to a truncated dmesg, please reboot and relaunch this script"
else
pvulnstatus $cve VULN "PTI is needed to mitigate the vulnerability"
if [ -n "$kpti_support" ]; then
if [ -e "/sys/kernel/debug/x86/pti_enabled" ]; then
explain "Your kernel supports PTI but it's disabled, you can enable it with \`echo 1 > /sys/kernel/debug/x86/pti_enabled\`"
elif grep -q -w nopti -w pti=off /proc/cmdline; then
explain "Your kernel supports PTI but it has been disabled on command-line, remove the nopti or pti=off option from your bootloader configuration"
else
explain "Your kernel supports PTI but it has been disabled, check \`dmesg\` right after boot to find clues why the system disabled it"
fi
else
explain "If you're using a distro kernel, upgrade your distro to get the latest kernel available. Otherwise, recompile the kernel with the CONFIG_PAGE_TABLE_ISOLATION option (named CONFIG_KAISER for some kernels), or the CONFIG_UNMAP_KERNEL_AT_EL0 option (for ARM64)"
fi
fi
else
if [ -n "$kpti_support" ]; 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"
explain "If you're using a distro kernel, upgrade your distro to get the latest kernel available. Otherwise, recompile the kernel with the CONFIG_PAGE_TABLE_ISOLATION option (named CONFIG_KAISER for some kernels), or the CONFIG_UNMAP_KERNEL_AT_EL0 option (for ARM64)"
else
pvulnstatus $cve UNK "offline mode: not enough information"
explain "Re-run this script with root privileges, and give it the kernel image (--kernel), the kernel configuration (--config) and the System.map file (--map) corresponding to the kernel you would like to inspect."
fi
fi
else
if [ "$xen_pv_domo" = 1 ]; then
msg="Xen Dom0s are safe and do not require PTI"
status="OK"
elif [ "$xen_pv_domu" = 1 ]; then
msg="Xen PV DomUs are vulnerable and need to be run in HVM, PVHVM, PVH mode, or the Xen hypervisor must have the Xen's own PTI patch"
status="VULN"
_explain="Go to https://blog.xenproject.org/2018/01/22/xen-project-spectre-meltdown-faq-jan-22-update/ for more information"
elif [ "$msg" = "Vulnerable" ]; then
msg="PTI is needed to mitigate the vulnerability"
_explain="If you're using a distro kernel, upgrade your distro to get the latest kernel available. Otherwise, recompile the kernel with the CONFIG_PAGE_TABLE_ISOLATION option (named CONFIG_KAISER for some kernels), or the CONFIG_UNMAP_KERNEL_AT_EL0 option (for ARM64)"
fi
pvulnstatus $cve "$status" "$msg"
[ -z "$_explain" ] && [ "$msg" = "Vulnerable" ] && _explain="If you're using a distro kernel, upgrade your distro to get the latest kernel available. Otherwise, recompile the kernel with the CONFIG_PAGE_TABLE_ISOLATION option (named CONFIG_KAISER for some kernels), or the CONFIG_UNMAP_KERNEL_AT_EL0 option (for ARM64)"
[ -n "$_explain" ] && explain "$_explain"
unset _explain
fi
# Warn the user about XSA-254 recommended mitigations
if [ "$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_CVE_2017_5754_bsd()
{
_info_nol "* Kernel supports Page Table Isolation (PTI): "
kpti_enabled=$(sysctl -n vm.pmap.pti 2>/dev/null)
if [ -z "$kpti_enabled" ]; then
pstatus yellow NO
else
pstatus green YES
fi
_info_nol " * PTI enabled and active: "
if [ "$kpti_enabled" = 1 ]; then
pstatus green YES
else
pstatus yellow NO
fi
pti_performance_check
if ! is_cpu_vulnerable "$cve"; then
# override status & msg in case CPU is not vulnerable after all
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
elif [ "$kpti_enabled" = 1 ]; then
pvulnstatus $cve OK "PTI mitigates the vulnerability"
elif [ -n "$kpti_enabled" ]; then
pvulnstatus $cve VULN "PTI is supported but disabled on your system"
else
pvulnstatus $cve VULN "PTI is needed to mitigate the vulnerability"
fi
}
####################
# VARIANT 3A SECTION
# rogue system register read aka 'Variant 3a'
check_CVE_2018_3640()
{
cve='CVE-2018-3640'
_info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m"
status=UNK
sys_interface_available=0
msg=''
_info_nol "* CPU microcode mitigates the vulnerability: "
if [ -n "$cpuid_ssbd" ]; then
# microcodes that ship with SSBD are known to also fix variant3a
# there is no specific cpuid bit as far as we know
pstatus green YES
else
pstatus yellow NO
fi
if ! is_cpu_vulnerable "$cve"; then
# override status & msg in case CPU is not vulnerable after all
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
elif [ -n "$cpuid_ssbd" ]; then
pvulnstatus $cve OK "your CPU microcode mitigates the vulnerability"
else
pvulnstatus $cve VULN "an up-to-date CPU microcode is needed to mitigate this vulnerability"
explain "The microcode of your CPU needs to be upgraded to mitigate this vulnerability. This is usually done at boot time by your kernel (the upgrade is not persistent across reboots which is why it's done at each boot). If you're using a distro, make sure you are up to date, as microcode updates are usually shipped alongside with the distro kernel. Availability of a microcode update for you CPU model depends on your CPU vendor. You can usually find out online if a microcode update is available for your CPU by searching for your CPUID (indicated in the Hardware Check section). The microcode update is enough, there is no additional OS, kernel or software change needed."
fi
}
###################
# VARIANT 4 SECTION
# speculative store bypass aka 'Variant 4'
check_CVE_2018_3639()
{
cve='CVE-2018-3639'
_info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m"
status=UNK
sys_interface_available=0
msg=''
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/spec_store_bypass"; then
# this kernel has the /sys interface, trust it over everything
sys_interface_available=1
fi
if [ "$opt_sysfs_only" != 1 ]; then
_info_nol "* Kernel supports speculation store bypass: "
if [ "$opt_live" = 1 ]; then
if grep -Eq 'Speculation.?Store.?Bypass:' /proc/self/status 2>/dev/null; then
kernel_ssb='found in /proc/self/status'
_debug "found Speculation.Store.Bypass: in /proc/self/status"
fi
fi
if [ -z "$kernel_ssb" ] && [ -n "$kernel" ]; then
kernel_ssb=$("${opt_arch_prefix}strings" "$kernel" | grep spec_store_bypass | head -n1);
[ -n "$kernel_ssb" ] && _debug "found $kernel_ssb in kernel"
fi
if [ -z "$kernel_ssb" ] && [ -n "$opt_map" ]; then
kernel_ssb=$(grep spec_store_bypass "$opt_map" | head -n1)
[ -n "$kernel_ssb" ] && _debug "found $kernel_ssb in System.map"
fi
if [ -n "$kernel_ssb" ]; then
pstatus green YES "$kernel_ssb"
else
pstatus yellow NO
fi
elif [ "$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
if ! is_cpu_vulnerable "$cve"; 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" ] || [ "$msg" = "Vulnerable" ]; then
# if msg is empty, sysfs check didn't fill it, rely on our own test
if [ -n "$cpuid_ssbd" ]; then
if [ -n "$kernel_ssb" ]; then
pvulnstatus $cve OK "your system provides the necessary tools for software mitigation"
else
pvulnstatus $cve VULN "your kernel needs to be updated"
explain "You have a recent-enough CPU microcode but your kernel is too old to use the new features exported by your CPU's microcode. If you're using a distro kernel, upgrade your distro to get the latest kernel available. Otherwise, recompile the kernel from recent-enough sources."
fi
else
if [ -n "$kernel_ssb" ]; then
pvulnstatus $cve VULN "Your CPU doesn't support SSBD"
explain "Your kernel is recent enough to use the CPU microcode features for mitigation, but your CPU microcode doesn't actually provide the necessary features for the kernel to use. The microcode of your CPU hence needs to be upgraded. This is usually done at boot time by your kernel (the upgrade is not persistent across reboots which is why it's done at each boot). If you're using a distro, make sure you are up to date, as microcode updates are usually shipped alongside with the distro kernel. Availability of a microcode update for you CPU model depends on your CPU vendor. You can usually find out online if a microcode update is available for your CPU by searching for your CPUID (indicated in the Hardware Check section)."
else
pvulnstatus $cve VULN "Neither your CPU nor your kernel support SSBD"
explain "Both your CPU microcode and your kernel are lacking support for mitigation. If you're using a distro kernel, upgrade your distro to get the latest kernel available. Otherwise, recompile the kernel from recent-enough sources. The microcode of your CPU also needs to be upgraded. This is usually done at boot time by your kernel (the upgrade is not persistent across reboots which is why it's done at each boot). If you're using a distro, make sure you are up to date, as microcode updates are usually shipped alongside with the distro kernel. Availability of a microcode update for you CPU model depends on your CPU vendor. You can usually find out online if a microcode update is available for your CPU by searching for your CPUID (indicated in the Hardware Check section)."
fi
fi
else
pvulnstatus $cve "$status" "$msg"
fi
}
###########################
# L1TF / FORESHADOW SECTION
# L1 terminal fault (SGX) aka 'Foreshadow'
check_CVE_2018_3615()
{
cve='CVE-2018-3615'
_info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m"
_info_nol "* CPU microcode mitigates the vulnerability: "
if [ "$cpu_flush_cmd" = 1 ] && [ "$cpuid_sgx" = 1 ]; then
# no easy way to detect a fixed SGX but we know that
# microcodes that have the FLUSH_CMD MSR also have the
# fixed SGX (for CPUs that support it)
pstatus green YES
elif [ "$cpuid_sgx" = 1 ]; then
pstatus red NO
else
pstatus blue N/A
fi
if ! is_cpu_vulnerable "$cve"; then
# override status & msg in case CPU is not vulnerable after all
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
elif [ "$cpuid_sgx" = 1 ]; then
if [ "$cpu_flush_cmd" = 1 ]; then
pvulnstatus $cve OK "your CPU microcode mitigates the vulnerability"
else
pvulnstatus $cve VULN "your CPU supports SGX and the microcode is not up to date"
fi
else
pvulnstatus $cve UNK "couldn't tell if your CPU supports SGX"
fi
}
# L1 terminal fault (OS) aka 'Foreshadow-NG (OS)'
check_CVE_2018_3620()
{
cve='CVE-2018-3620'
_info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m"
status=UNK
sys_interface_available=0
msg=''
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/l1tf" '^[^;]+'; then
# this kernel has the /sys interface, trust it over everything
sys_interface_available=1
fi
if [ "$opt_sysfs_only" != 1 ]; then
_info_nol "* Kernel supports PTE inversion: "
if ! which "${opt_arch_prefix}strings" >/dev/null 2>&1; then
pteinv_supported=-1
else
if "${opt_arch_prefix}strings" "$kernel" | grep -Fq 'PTE Inversion'; then
pstatus green YES "found in kernel image"
_debug "pteinv: found pte inversion evidence in kernel image"
pteinv_supported=1
else
pstatus yellow NO
pteinv_supported=0
fi
fi
_info_nol "* PTE inversion enabled and active: "
if [ "$opt_live" = 1 ]; then
if [ "$sys_interface_available" = 1 ]; then
if grep -q 'Mitigation: PTE Inversion' /sys/devices/system/cpu/vulnerabilities/l1tf; then
pstatus green YES
pteinv_active=1
else
pstatus yellow NO
pteinv_active=0
fi
else
pstatus yellow UNKNOWN "sysfs interface not available"
pteinv_active=-1
fi
else
pstatus blue N/A "not testable in offline mode"
fi
elif [ "$sys_interface_available" = 0 ]; then
# we have no sysfs but were asked to use it only!
msg="/sys vulnerability interface use forced, but it's not available!"
status=UNK
fi
if ! is_cpu_vulnerable "$cve"; 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 [ "$pteinv_supported" = 1 ]; then
if [ "$pteinv_active" = 1 ] || [ "$opt_live" != 1 ]; then
pvulnstatus $cve OK "PTE inversion mitigates the vunerability"
else
pvulnstatus $cve VULN "Your kernel supports PTE inversion but it doesn't seem to be enabled"
fi
else
pvulnstatus $cve VULN "Your kernel doesn't support PTE inversion, update it"
fi
else
pvulnstatus $cve "$status" "$msg"
fi
}
# L1TF VMM
check_CVE_2018_3646()
{
cve='CVE-2018-3646'
_info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m"
status=UNK
sys_interface_available=0
msg=''
if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/l1tf" 'VMX:.*' silent; then
# this kernel has the /sys interface, trust it over everything
sys_interface_available=1
fi
if [ "$opt_sysfs_only" != 1 ]; then
_info_nol "* This system is a host running an hypervisor: "
has_vmm=$opt_vmm
if [ "$has_vmm" = -1 ]; then
# FIXME enhance detection, this one is pretty basic/stupid
has_vmm=0
# shellcheck disable=SC2009
ps ax | grep -v -e grep -e '\[kvm' | grep -q -e qemu -e kvm && has_vmm=1
fi
if [ "$has_vmm" = 0 ]; then
if [ "$opt_vmm" != -1 ]; then
pstatus green NO "forced from command line"
else
pstatus green NO
fi
else
if [ "$opt_vmm" != -1 ]; then
pstatus blue YES "forced from command line"
else
pstatus blue YES
fi
fi
_info "* Mitigation 1 (KVM)"
_info_nol " * EPT is disabled: "
if [ "$opt_live" = 1 ]; then
if ! [ -r /sys/module/kvm_intel/parameters/ept ]; then
pstatus blue N/A "the kvm_intel module is not loaded"
elif [ "$(cat /sys/module/kvm_intel/parameters/ept)" = N ]; then
pstatus green YES
ept_disabled=1
else
pstatus yellow NO
fi
else
pstatus blue N/A "not testable in offline mode"
fi
_info "* Mitigation 2"
_info_nol " * L1D flush is supported by kernel: "
if [ "$opt_live" = 1 ] && grep -qw flush_l1d /proc/cpuinfo; then
l1d_kernel='found flush_l1d in /proc/cpuinfo'
fi
if [ -z "$l1d_kernel" ]; then
if ! which "${opt_arch_prefix}strings" >/dev/null 2>&1; then
l1d_kernel_err="missing '${opt_arch_prefix}strings' tool, please install it, usually it's in the binutils package"
elif [ -n "$kernel_err" ]; then
l1d_kernel_err="$kernel_err"
elif "${opt_arch_prefix}strings" "$kernel" | grep -qw flush_l1d; then
l1d_kernel='found flush_l1d in kernel image'
fi
fi
if [ -n "$l1d_kernel" ]; then
pstatus green YES "$l1d_kernel"
elif [ -n "$l1d_kernel_err" ]; then
pstatus yellow UNKNOWN "$l1d_kernel_err"
else
pstatus yellow NO
fi
_info_nol " * L1D flush enabled: "
if [ "$opt_live" = 1 ]; then
if [ -r "/sys/devices/system/cpu/vulnerabilities/l1tf" ]; then
if grep -Eq 'VMX: (L1D )?vulnerable' "/sys/devices/system/cpu/vulnerabilities/l1tf"; then
l1d_mode=0
pstatus yellow NO
elif grep -Eq 'VMX: (L1D )?conditional cache flushes' "/sys/devices/system/cpu/vulnerabilities/l1tf"; then
l1d_mode=1
pstatus green YES "conditional flushes"
elif grep -Eq 'VMX: (L1D )?cache flushes' "/sys/devices/system/cpu/vulnerabilities/l1tf"; then
l1d_mode=2
pstatus green YES "unconditional flushes"
else
l1d_mode=-1
pstatus yellow UNKNOWN "unrecognized mode"
fi
else
pstatus yellow UNKNOWN "can't find or read /sys/devices/system/cpu/vulnerabilities/l1tf"
fi
else
pstatus blue N/A "not testable in offline mode"
fi
_info_nol " * Hardware-backed L1D flush supported: "
if [ "$opt_live" = 1 ]; then
if grep -qw flush_l1d /proc/cpuinfo; then
pstatus green YES "performance impact of the mitigation will be greatly reduced"
else
pstatus blue NO "flush will be done in software, this is slower"
fi
else
pstatus blue N/A "not testable in offline mode"
fi
_info_nol " * Hyper-Threading (SMT) is enabled: "
is_cpu_smt_enabled; smt_enabled=$?
if [ "$smt_enabled" = 0 ]; then
pstatus yellow YES
elif [ "$smt_enabled" = 1 ]; then
pstatus green NO
else
pstatus yellow UNKNOWN
fi
elif [ "$sys_interface_available" = 0 ]; then
# we have no sysfs but were asked to use it only!
msg="/sys vulnerability interface use forced, but it's not available!"
status=UNK
fi
if ! is_cpu_vulnerable "$cve"; then
# override status & msg in case CPU is not vulnerable after all
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
elif [ "$has_vmm" = 0 ]; then
pvulnstatus $cve OK "this system is not running an hypervisor"
else
if [ "$ept_disabled" = 1 ]; then
pvulnstatus $cve OK "EPT is disabled which mitigates the vulnerability"
elif [ "$opt_paranoid" = 0 ]; then
if [ "$l1d_mode" -ge 1 ]; then
pvulnstatus $cve OK "L1D flushing is enabled and mitigates the vulnerability"
else
pvulnstatus $cve VULN "disable EPT or enabled L1D flushing to mitigate the vulnerability"
fi
else
if [ "$l1d_mode" -ge 2 ]; then
if [ "$smt_enabled" = 1 ]; then
pvulnstatus $cve OK "L1D unconditional flushing and Hyper-Threading disabled are mitigating the vulnerability"
else
pvulnstatus $cve VULN "Hyper-Threading must be disabled to fully mitigate the vulnerability"
fi
else
if [ "$smt_enabled" = 1 ]; then
pvulnstatus $cve VULN "L1D unconditional flushing should be enabled to fully mitigate the vulnerability"
else
pvulnstatus $cve VULN "enable L1D unconditional flushing and disable Hyper-Threading to fully mitigate the vulnerability"
fi
fi
fi
fi
}
if [ "$opt_no_hw" = 0 ] && [ -z "$opt_arch_prefix" ]; then
check_cpu
check_cpu_vulnerabilities
_info
fi
# now run the checks the user asked for
for cve in $supported_cve_list
do
if [ "$opt_cve_all" = 1 ] || echo "$opt_cve_list" | grep -qw "$cve"; then
check_"$(echo "$cve" | tr - _)"
_info
fi
done
_info "> \033[46m\033[30mSUMMARY:\033[0m$final_summary"
_info ""
_vars=$(set | grep -Ev '^[A-Z_[:space:]]' | sort | tr "\n" '|')
_debug "variables at end of script: $_vars"
if [ "$opt_explain" = 0 ]; then
_info "Need more detailed information about mitigation options? Use --explain"
fi
_info "A false sense of security is worse than no security at all, see --disclaimer"
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" = "short" ]; then
_echo 0 "${short_output% }"
fi
if [ "$opt_batch" = 1 ] && [ "$opt_batch_format" = "json" ]; then
_echo 0 "${json_output%?}]"
fi
if [ "$opt_batch" = 1 ] && [ "$opt_batch_format" = "prometheus" ]; then
echo "# TYPE specex_vuln_status untyped"
echo "# HELP specex_vuln_status Exposure of system to speculative execution vulnerabilities"
printf "%b\n" "$prometheus_output"
fi
# exit with the proper exit code
[ "$global_critical" = 1 ] && exit 2 # critical
[ "$global_unknown" = 1 ] && exit 3 # unknown
exit 0 # ok
Reference in New Issue View Git Blame Copy Permalink