add --variant to specify what check we want to run
This commit is contained in:
Stéphane Lesimple
parent
5389ac6844
commit
74bc7ba637
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@ -8,7 +8,7 @@
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#
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#
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# Stephane Lesimple
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# Stephane Lesimple
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#
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#
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VERSION=0.21
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VERSION=0.22
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# Script configuration
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# Script configuration
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show_usage()
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show_usage()
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@ -34,8 +34,10 @@ show_usage()
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Options:
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Options:
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--no-color Don't use color codes
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--no-color Don't use color codes
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-v, --verbose Increase verbosity level
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-v, --verbose Increase verbosity level
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--batch Produce machine readable output
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--batch text Produce machine readable output, this is the default if --batch is specified alone
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--batch nrpe Produce machine readable output formatted for NRPE
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--batch nrpe Produce machine readable output formatted for NRPE
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--variant [1,2,3] Specify which variant you'd like to check, by default all variants are checked
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Can be specified multiple times (e.g. --variant 2 --variant 3)
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IMPORTANT:
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IMPORTANT:
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A false sense of security is worse than no security at all.
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A false sense of security is worse than no security at all.
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@ -79,6 +81,10 @@ opt_no_color=0
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opt_batch=0
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opt_batch=0
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opt_batch_format="text"
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opt_batch_format="text"
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opt_verbose=1
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opt_verbose=1
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opt_variant1=0
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opt_variant2=0
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opt_variant3=0
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opt_allvariants=1
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nrpe_critical=0
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nrpe_critical=0
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nrpe_unknown=0
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nrpe_unknown=0
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@ -255,6 +261,20 @@ while [ -n "$1" ]; do
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elif [ "$1" = "-v" -o "$1" = "--verbose" ]; then
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elif [ "$1" = "-v" -o "$1" = "--verbose" ]; then
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opt_verbose=$(expr $opt_verbose + 1)
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opt_verbose=$(expr $opt_verbose + 1)
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shift
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shift
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elif [ "$1" = "--variant" ]; then
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if [ -z "$2" ]; then
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echo "$0: error: option --variant expects a parameter (1, 2 or 3)" >&2
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exit 1
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fi
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case "$2" in
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1) opt_variant1=1; opt_allvariants=0;;
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2) opt_variant2=1; opt_allvariants=0;;
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3) opt_variant3=1; opt_allvariants=0;;
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*)
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echo "$0: error: invalid parameter '$2' for --variant, expected either 1, 2 or 3" >&2;
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exit 1;;
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esac
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shift 2
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elif [ "$1" = "-h" -o "$1" = "--help" ]; then
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elif [ "$1" = "-h" -o "$1" = "--help" ]; then
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show_header
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show_header
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show_usage
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show_usage
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@ -467,293 +487,330 @@ fi
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_info
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_info
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###########
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# end of header stuff
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# SPECTRE 1
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_info "\033[1;34mCVE-2017-5753 [bounds check bypass] aka 'Spectre Variant 1'\033[0m"
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_info_nol "* Checking count of LFENCE opcodes in kernel: "
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status=0
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# now we define some util functions and the check_*() funcs, as
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if [ -n "$vmlinux_err" ]; then
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# the user can choose to execute only some of those
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pstatus yellow UNKNOWN "$vmlinux_err"
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else
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if ! which objdump >/dev/null 2>&1; then
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pstatus yellow UNKNOWN "missing 'objdump' tool, please install it, usually it's in the binutils package"
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else
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# here we disassemble the kernel and count the number of occurences of the LFENCE opcode
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# in non-patched kernels, this has been empirically determined as being around 40-50
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# in patched kernels, this is more around 70-80, sometimes way higher (100+)
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# v0.13: 68 found in a 3.10.23-xxxx-std-ipv6-64 (with lots of modules compiled-in directly), which doesn't have the LFENCE patches,
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# so let's push the threshold to 70.
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# TODO LKML patch is starting to dump LFENCE in favor of the PAUSE opcode, we might need to check that (patch not stabilized yet)
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nb_lfence=$(objdump -D "$vmlinux" | grep -wc lfence)
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if [ "$nb_lfence" -lt 70 ]; then
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pstatus red NO "only $nb_lfence opcodes found, should be >= 70"
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status=1
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else
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pstatus green YES "$nb_lfence opcodes found, which is >= 70"
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status=2
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fi
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fi
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fi
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if ! is_cpu_vulnerable 1; then
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mount_debugfs()
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pvulnstatus CVE-2017-5753 OK "your CPU vendor reported your CPU model as not vulnerable"
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{
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else
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case "$status" in
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0) pvulnstatus CVE-2017-5753 UNK "impossible to check ${vmlinux}";;
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1) pvulnstatus CVE-2017-5753 VULN 'heuristic to be improved when official patches become available';;
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2) pvulnstatus CVE-2017-5753 OK 'heuristic to be improved when official patches become available';;
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esac
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fi
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###########
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# VARIANT 2
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_info
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_info "\033[1;34mCVE-2017-5715 [branch target injection] aka 'Spectre Variant 2'\033[0m"
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_info "* Mitigation 1"
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_info_nol "* Hardware (CPU microcode) support for mitigation: "
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if [ ! -e /dev/cpu/0/msr ]; then
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# try to load the module ourselves (and remember it so we can rmmod it afterwards)
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modprobe msr 2>/dev/null && insmod_msr=1
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fi
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if [ ! -e /dev/cpu/0/msr ]; then
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pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/msr, is msr support enabled in your kernel?"
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else
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# the new MSR 'SPEC_CTRL' is at offset 0x48
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# here we use dd, it's the same as using 'rdmsr 0x48' but without needing the rdmsr tool
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# if we get a read error, the MSR is not there
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dd if=/dev/cpu/0/msr of=/dev/null bs=8 count=1 skip=9 2>/dev/null
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if [ $? -eq 0 ]; then
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pstatus green YES
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else
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pstatus red NO
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fi
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fi
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if [ "$insmod_msr" = 1 ]; then
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# if we used modprobe ourselves, rmmod the module
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rmmod msr 2>/dev/null
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fi
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_info_nol "* Kernel support for IBRS: "
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if [ "$opt_live" = 1 ]; then
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if [ ! -e /sys/kernel/debug/sched_features ]; then
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if [ ! -e /sys/kernel/debug/sched_features ]; then
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# try to mount the debugfs hierarchy ourselves and remember it to umount afterwards
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# try to mount the debugfs hierarchy ourselves and remember it to umount afterwards
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mount -t debugfs debugfs /sys/kernel/debug 2>/dev/null && mounted_debugfs=1
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mount -t debugfs debugfs /sys/kernel/debug 2>/dev/null && mounted_debugfs=1
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fi
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fi
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if [ -e /sys/kernel/debug/ibrs_enabled ]; then
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}
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# if the file is there, we have IBRS compiled-in
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pstatus green YES
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umount_debugfs()
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ibrs_supported=1
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{
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ibrs_enabled=$(cat /sys/kernel/debug/ibrs_enabled 2>/dev/null)
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if [ "$mounted_debugfs" = 1 ]; then
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elif [ -e /sys/kernel/debug/x86/ibrs_enabled ]; then
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# umount debugfs if we did mount it ourselves
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# RedHat uses a different path (see https://access.redhat.com/articles/3311301)
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umount /sys/kernel/debug
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pstatus green YES
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ibrs_supported=1
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ibrs_enabled=$(cat /sys/kernel/debug/x86/ibrs_enabled 2>/dev/null)
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fi
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fi
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fi
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}
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if [ "$ibrs_supported" != 1 -a -n "$opt_map" ]; then
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if grep -q spec_ctrl "$opt_map"; then
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pstatus green YES
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ibrs_supported=1
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fi
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fi
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if [ "$ibrs_supported" != 1 ]; then
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pstatus red NO
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fi
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_info_nol "* IBRS enabled for Kernel space: "
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###################
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if [ "$opt_live" = 1 ]; then
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# SPECTRE VARIANT 1
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# 0 means disabled
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check_variant1()
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# 1 is enabled only for kernel space
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{
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# 2 is enabled for kernel and user space
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_info "\033[1;34mCVE-2017-5753 [bounds check bypass] aka 'Spectre Variant 1'\033[0m"
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case "$ibrs_enabled" in
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_info_nol "* Checking count of LFENCE opcodes in kernel: "
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"") [ "$ibrs_supported" = 1 ] && pstatus yellow UNKNOWN || pstatus red NO;;
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0) pstatus red NO;;
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1 | 2) pstatus green YES;;
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*) pstatus yellow UNKNOWN;;
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esac
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else
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pstatus blue N/A "not testable in offline mode"
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fi
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_info_nol "* IBRS enabled for User space: "
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status=0
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if [ "$opt_live" = 1 ]; then
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if [ -n "$vmlinux_err" ]; then
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case "$ibrs_enabled" in
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pstatus yellow UNKNOWN "$vmlinux_err"
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"") [ "$ibrs_supported" = 1 ] && pstatus yellow UNKNOWN || pstatus red NO;;
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0 | 1) pstatus red NO;;
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2) pstatus green YES;;
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*) pstatus yellow UNKNOWN;;
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esac
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else
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pstatus blue N/A "not testable in offline mode"
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fi
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_info "* Mitigation 2"
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_info_nol "* Kernel compiled with retpoline option: "
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# We check the RETPOLINE kernel options
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if [ -r "$opt_config" ]; then
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if grep -q '^CONFIG_RETPOLINE=y' "$opt_config"; then
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pstatus green YES
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retpoline=1
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else
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else
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pstatus red NO
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if ! which objdump >/dev/null 2>&1; then
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pstatus yellow UNKNOWN "missing 'objdump' tool, please install it, usually it's in the binutils package"
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else
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# here we disassemble the kernel and count the number of occurences of the LFENCE opcode
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# in non-patched kernels, this has been empirically determined as being around 40-50
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# in patched kernels, this is more around 70-80, sometimes way higher (100+)
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# 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,
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# so let's push the threshold to 70.
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# TODO LKML patch is starting to dump LFENCE in favor of the PAUSE opcode, we might need to check that (patch not stabilized yet)
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nb_lfence=$(objdump -D "$vmlinux" | grep -wc lfence)
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if [ "$nb_lfence" -lt 70 ]; then
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pstatus red NO "only $nb_lfence opcodes found, should be >= 70"
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status=1
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else
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pstatus green YES "$nb_lfence opcodes found, which is >= 70"
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status=2
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fi
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fi
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fi
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fi
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else
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pstatus yellow UNKNOWN "couldn't read your kernel configuration"
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fi
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_info_nol "* Kernel compiled with a retpoline-aware compiler: "
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if ! is_cpu_vulnerable 1; then
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# Now check if the compiler used to compile the kernel knows how to insert retpolines in generated asm
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pvulnstatus CVE-2017-5753 OK "your CPU vendor reported your CPU model as not vulnerable"
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# For gcc, this is -mindirect-branch=thunk-extern (detected by the kernel makefiles)
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# See gcc commit https://github.com/hjl-tools/gcc/commit/23b517d4a67c02d3ef80b6109218f2aadad7bd79
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# In latest retpoline LKML patches, the noretpoline_setup symbol exists only if CONFIG_RETPOLINE is set
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# *AND* if the compiler is retpoline-compliant, so look for that symbol
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if [ -n "$opt_map" ]; then
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# look for the symbol
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if grep -qw noretpoline_setup "$opt_map"; then
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retpoline_compiler=1
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pstatus green YES "noretpoline_setup symbol found in System.map"
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else
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else
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pstatus red NO
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case "$status" in
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0) pvulnstatus CVE-2017-5753 UNK "impossible to check ${vmlinux}";;
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1) pvulnstatus CVE-2017-5753 VULN 'heuristic to be improved when official patches become available';;
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2) pvulnstatus CVE-2017-5753 OK 'heuristic to be improved when official patches become available';;
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esac
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fi
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fi
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elif [ -n "$vmlinux" ]; then
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}
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# look for the symbol
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if which nm >/dev/null 2>&1; then
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###################
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# the proper way: use nm and look for the symbol
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# SPECTRE VARIANT 2
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if nm "$vmlinux" 2>/dev/null | grep -qw 'noretpoline_setup'; then
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check_variant2()
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retpoline_compiler=1
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{
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pstatus green YES "noretpoline_setup found in vmlinux symbols"
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_info "\033[1;34mCVE-2017-5715 [branch target injection] aka 'Spectre Variant 2'\033[0m"
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_info "* Mitigation 1"
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_info_nol "* Hardware (CPU microcode) support for mitigation: "
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if [ ! -e /dev/cpu/0/msr ]; then
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# try to load the module ourselves (and remember it so we can rmmod it afterwards)
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modprobe msr 2>/dev/null && insmod_msr=1
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fi
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if [ ! -e /dev/cpu/0/msr ]; then
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pstatus yellow UNKNOWN "couldn't read /dev/cpu/0/msr, is msr support enabled in your kernel?"
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else
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# the new MSR 'SPEC_CTRL' is at offset 0x48
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# here we use dd, it's the same as using 'rdmsr 0x48' but without needing the rdmsr tool
|
||||||
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# if we get a read error, the MSR is not there
|
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dd if=/dev/cpu/0/msr of=/dev/null bs=8 count=1 skip=9 2>/dev/null
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if [ $? -eq 0 ]; then
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pstatus green YES
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else
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else
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pstatus red NO
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pstatus red NO
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fi
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fi
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elif grep -q noretpoline_setup "$vmlinux"; then
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fi
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# if we don't have nm, nevermind, the symbol name is long enough to not have
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# any false positive using good old grep directly on the binary
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if [ "$insmod_msr" = 1 ]; then
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retpoline_compiler=1
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# if we used modprobe ourselves, rmmod the module
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pstatus green YES "noretpoline_setup found in vmlinux"
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rmmod msr 2>/dev/null
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else
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fi
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_info_nol "* Kernel support for IBRS: "
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if [ "$opt_live" = 1 ]; then
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mount_debugfs
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if [ -e /sys/kernel/debug/ibrs_enabled ]; then
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# if the file is there, we have IBRS compiled-in
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||||||
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pstatus green YES
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ibrs_supported=1
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ibrs_enabled=$(cat /sys/kernel/debug/ibrs_enabled 2>/dev/null)
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elif [ -e /sys/kernel/debug/x86/ibrs_enabled ]; then
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# RedHat uses a different path (see https://access.redhat.com/articles/3311301)
|
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pstatus green YES
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ibrs_supported=1
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ibrs_enabled=$(cat /sys/kernel/debug/x86/ibrs_enabled 2>/dev/null)
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fi
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fi
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if [ "$ibrs_supported" != 1 -a -n "$opt_map" ]; then
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if grep -q spec_ctrl "$opt_map"; then
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pstatus green YES
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ibrs_supported=1
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fi
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fi
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if [ "$ibrs_supported" != 1 ]; then
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pstatus red NO
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pstatus red NO
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||||||
fi
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fi
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else
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pstatus yellow UNKNOWN "couldn't find your kernel image or System.map"
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fi
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if ! is_cpu_vulnerable 2; then
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_info_nol "* IBRS enabled for Kernel space: "
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||||||
pvulnstatus CVE-2017-5715 OK "your CPU vendor reported your CPU model as not vulnerable"
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if [ "$opt_live" = 1 ]; then
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elif [ "$retpoline" = 1 -a "$retpoline_compiler" = 1 ]; then
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# 0 means disabled
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pvulnstatus CVE-2017-5715 OK "retpoline mitigate the vulnerability"
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# 1 is enabled only for kernel space
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elif [ "$opt_live" = 1 ]; then
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# 2 is enabled for kernel and user space
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if [ "$ibrs_enabled" = 1 -o "$ibrs_enabled" = 2 ]; then
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case "$ibrs_enabled" in
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||||||
pvulnstatus CVE-2017-5715 OK "IBRS mitigates the vulnerability"
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"") [ "$ibrs_supported" = 1 ] && pstatus yellow UNKNOWN || pstatus red NO;;
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0) pstatus red NO;;
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||||||
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1 | 2) pstatus green YES;;
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||||||
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*) pstatus yellow UNKNOWN;;
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esac
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else
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else
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pvulnstatus CVE-2017-5715 VULN "IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
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pstatus blue N/A "not testable in offline mode"
|
||||||
fi
|
fi
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else
|
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||||||
if [ "$ibrs_supported" = 1 ]; then
|
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pvulnstatus CVE-2017-5715 OK "offline mode: IBRS will mitigate the vulnerability if enabled at runtime"
|
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else
|
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pvulnstatus CVE-2017-5715 VULN "IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
|
|
||||||
fi
|
|
||||||
fi
|
|
||||||
|
|
||||||
##########
|
_info_nol "* IBRS enabled for User space: "
|
||||||
# MELTDOWN
|
if [ "$opt_live" = 1 ]; then
|
||||||
_info
|
case "$ibrs_enabled" in
|
||||||
_info "\033[1;34mCVE-2017-5754 [rogue data cache load] aka 'Meltdown' aka 'Variant 3'\033[0m"
|
"") [ "$ibrs_supported" = 1 ] && pstatus yellow UNKNOWN || pstatus red NO;;
|
||||||
_info_nol "* Kernel supports Page Table Isolation (PTI): "
|
0 | 1) pstatus red NO;;
|
||||||
kpti_support=0
|
2) pstatus green YES;;
|
||||||
kpti_can_tell=0
|
*) pstatus yellow UNKNOWN;;
|
||||||
if [ -n "$opt_config" ]; then
|
esac
|
||||||
kpti_can_tell=1
|
|
||||||
if grep -Eq '^(CONFIG_PAGE_TABLE_ISOLATION|CONFIG_KAISER)=y' "$opt_config"; then
|
|
||||||
kpti_support=1
|
|
||||||
fi
|
|
||||||
fi
|
|
||||||
if [ "$kpti_support" = 0 -a -n "$opt_map" ]; then
|
|
||||||
# it's not an elif: some backports don't have the PTI config but still include the patch
|
|
||||||
# so we try to find an exported symbol that is part of the PTI patch in System.map
|
|
||||||
kpti_can_tell=1
|
|
||||||
if grep -qw kpti_force_enabled "$opt_map"; then
|
|
||||||
kpti_support=1
|
|
||||||
fi
|
|
||||||
fi
|
|
||||||
if [ "$kpti_support" = 0 -a -n "$vmlinux" ]; then
|
|
||||||
# same as above but in case we don't have System.map and only vmlinux, look for the
|
|
||||||
# nopti option that is part of the patch (kernel command line option)
|
|
||||||
kpti_can_tell=1
|
|
||||||
if ! which strings >/dev/null 2>&1; then
|
|
||||||
pstatus yellow UNKNOWN "missing 'strings' tool, please install it, usually it's in the binutils package"
|
|
||||||
else
|
else
|
||||||
if strings "$vmlinux" | grep -qw nopti; then
|
pstatus blue N/A "not testable in offline mode"
|
||||||
|
fi
|
||||||
|
|
||||||
|
_info "* Mitigation 2"
|
||||||
|
_info_nol "* Kernel compiled with retpoline option: "
|
||||||
|
# We check the RETPOLINE kernel options
|
||||||
|
if [ -r "$opt_config" ]; then
|
||||||
|
if grep -q '^CONFIG_RETPOLINE=y' "$opt_config"; then
|
||||||
|
pstatus green YES
|
||||||
|
retpoline=1
|
||||||
|
else
|
||||||
|
pstatus red NO
|
||||||
|
fi
|
||||||
|
else
|
||||||
|
pstatus yellow UNKNOWN "couldn't read your kernel configuration"
|
||||||
|
fi
|
||||||
|
|
||||||
|
_info_nol "* Kernel compiled with a retpoline-aware compiler: "
|
||||||
|
# Now check if the compiler used to compile the kernel knows how to insert retpolines in generated asm
|
||||||
|
# For gcc, this is -mindirect-branch=thunk-extern (detected by the kernel makefiles)
|
||||||
|
# See gcc commit https://github.com/hjl-tools/gcc/commit/23b517d4a67c02d3ef80b6109218f2aadad7bd79
|
||||||
|
# In latest retpoline LKML patches, the noretpoline_setup symbol exists only if CONFIG_RETPOLINE is set
|
||||||
|
# *AND* if the compiler is retpoline-compliant, so look for that symbol
|
||||||
|
if [ -n "$opt_map" ]; then
|
||||||
|
# look for the symbol
|
||||||
|
if grep -qw noretpoline_setup "$opt_map"; then
|
||||||
|
retpoline_compiler=1
|
||||||
|
pstatus green YES "noretpoline_setup symbol found in System.map"
|
||||||
|
else
|
||||||
|
pstatus red NO
|
||||||
|
fi
|
||||||
|
elif [ -n "$vmlinux" ]; then
|
||||||
|
# look for the symbol
|
||||||
|
if which nm >/dev/null 2>&1; then
|
||||||
|
# the proper way: use nm and look for the symbol
|
||||||
|
if nm "$vmlinux" 2>/dev/null | grep -qw 'noretpoline_setup'; then
|
||||||
|
retpoline_compiler=1
|
||||||
|
pstatus green YES "noretpoline_setup found in vmlinux symbols"
|
||||||
|
else
|
||||||
|
pstatus red NO
|
||||||
|
fi
|
||||||
|
elif grep -q noretpoline_setup "$vmlinux"; then
|
||||||
|
# if we don't have nm, nevermind, the symbol name is long enough to not have
|
||||||
|
# any false positive using good old grep directly on the binary
|
||||||
|
retpoline_compiler=1
|
||||||
|
pstatus green YES "noretpoline_setup found in vmlinux"
|
||||||
|
else
|
||||||
|
pstatus red NO
|
||||||
|
fi
|
||||||
|
else
|
||||||
|
pstatus yellow UNKNOWN "couldn't find your kernel image or System.map"
|
||||||
|
fi
|
||||||
|
|
||||||
|
if ! is_cpu_vulnerable 2; then
|
||||||
|
pvulnstatus CVE-2017-5715 OK "your CPU vendor reported your CPU model as not vulnerable"
|
||||||
|
elif [ "$retpoline" = 1 -a "$retpoline_compiler" = 1 ]; then
|
||||||
|
pvulnstatus CVE-2017-5715 OK "retpoline mitigate the vulnerability"
|
||||||
|
elif [ "$opt_live" = 1 ]; then
|
||||||
|
if [ "$ibrs_enabled" = 1 -o "$ibrs_enabled" = 2 ]; then
|
||||||
|
pvulnstatus CVE-2017-5715 OK "IBRS mitigates the vulnerability"
|
||||||
|
else
|
||||||
|
pvulnstatus CVE-2017-5715 VULN "IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
|
||||||
|
fi
|
||||||
|
else
|
||||||
|
if [ "$ibrs_supported" = 1 ]; then
|
||||||
|
pvulnstatus CVE-2017-5715 OK "offline mode: IBRS will mitigate the vulnerability if enabled at runtime"
|
||||||
|
else
|
||||||
|
pvulnstatus CVE-2017-5715 VULN "IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
|
||||||
|
fi
|
||||||
|
fi
|
||||||
|
}
|
||||||
|
|
||||||
|
########################
|
||||||
|
# MELTDOWN aka VARIANT 3
|
||||||
|
check_variant3()
|
||||||
|
{
|
||||||
|
_info "\033[1;34mCVE-2017-5754 [rogue data cache load] aka 'Meltdown' aka 'Variant 3'\033[0m"
|
||||||
|
_info_nol "* Kernel supports Page Table Isolation (PTI): "
|
||||||
|
kpti_support=0
|
||||||
|
kpti_can_tell=0
|
||||||
|
if [ -n "$opt_config" ]; then
|
||||||
|
kpti_can_tell=1
|
||||||
|
if grep -Eq '^(CONFIG_PAGE_TABLE_ISOLATION|CONFIG_KAISER)=y' "$opt_config"; then
|
||||||
kpti_support=1
|
kpti_support=1
|
||||||
fi
|
fi
|
||||||
fi
|
fi
|
||||||
fi
|
if [ "$kpti_support" = 0 -a -n "$opt_map" ]; then
|
||||||
|
# it's not an elif: some backports don't have the PTI config but still include the patch
|
||||||
if [ "$kpti_support" = 1 ]; then
|
# so we try to find an exported symbol that is part of the PTI patch in System.map
|
||||||
pstatus green YES
|
kpti_can_tell=1
|
||||||
elif [ "$kpti_can_tell" = 1 ]; then
|
if grep -qw kpti_force_enabled "$opt_map"; then
|
||||||
pstatus red NO
|
kpti_support=1
|
||||||
else
|
fi
|
||||||
pstatus yellow UNKNOWN "couldn't read your kernel configuration nor System.map file"
|
|
||||||
fi
|
|
||||||
|
|
||||||
_info_nol "* PTI enabled and active: "
|
|
||||||
if [ "$opt_live" = 1 ]; then
|
|
||||||
if grep ^flags /proc/cpuinfo | grep -qw pti; then
|
|
||||||
# vanilla PTI patch sets the 'pti' flag in cpuinfo
|
|
||||||
kpti_enabled=1
|
|
||||||
elif grep ^flags /proc/cpuinfo | grep -qw kaiser; then
|
|
||||||
# kernel line 4.9 sets the 'kaiser' flag in cpuinfo
|
|
||||||
kpti_enabled=1
|
|
||||||
elif [ -e /sys/kernel/debug/x86/pti_enabled ]; then
|
|
||||||
# RedHat Backport creates a dedicated file, see https://access.redhat.com/articles/3311301
|
|
||||||
kpti_enabled=$(cat /sys/kernel/debug/x86/pti_enabled 2>/dev/null)
|
|
||||||
elif dmesg | grep -Eq 'Kernel/User page tables isolation: enabled|Kernel page table isolation enabled'; then
|
|
||||||
# if we can't find the flag, grep dmesg output
|
|
||||||
kpti_enabled=1
|
|
||||||
elif [ -r /var/log/dmesg ] && grep -Eq 'Kernel/User page tables isolation: enabled|Kernel page table isolation enabled' /var/log/dmesg; then
|
|
||||||
# if we can't find the flag in dmesg output, grep in /var/log/dmesg when readable
|
|
||||||
kpti_enabled=1
|
|
||||||
else
|
|
||||||
kpti_enabled=0
|
|
||||||
fi
|
fi
|
||||||
if [ "$kpti_enabled" = 1 ]; then
|
if [ "$kpti_support" = 0 -a -n "$vmlinux" ]; then
|
||||||
pstatus green YES
|
# same as above but in case we don't have System.map and only vmlinux, look for the
|
||||||
else
|
# nopti option that is part of the patch (kernel command line option)
|
||||||
pstatus red NO
|
kpti_can_tell=1
|
||||||
|
if ! which strings >/dev/null 2>&1; then
|
||||||
|
pstatus yellow UNKNOWN "missing 'strings' tool, please install it, usually it's in the binutils package"
|
||||||
|
else
|
||||||
|
if strings "$vmlinux" | grep -qw nopti; then
|
||||||
|
kpti_support=1
|
||||||
|
fi
|
||||||
|
fi
|
||||||
fi
|
fi
|
||||||
else
|
|
||||||
pstatus blue N/A "can't verify if PTI is enabled in offline mode"
|
|
||||||
fi
|
|
||||||
|
|
||||||
if [ "$mounted_debugfs" = 1 ]; then
|
|
||||||
# umount debugfs if we did mount it ourselves
|
|
||||||
umount /sys/kernel/debug
|
|
||||||
fi
|
|
||||||
|
|
||||||
if ! is_cpu_vulnerable 3; then
|
|
||||||
pvulnstatus CVE-2017-5754 OK "your CPU vendor reported your CPU model as not vulnerable"
|
|
||||||
elif [ "$opt_live" = 1 ]; then
|
|
||||||
if [ "$kpti_enabled" = 1 ]; then
|
|
||||||
pvulnstatus CVE-2017-5754 OK "PTI mitigates the vulnerability"
|
|
||||||
else
|
|
||||||
pvulnstatus CVE-2017-5754 VULN "PTI is needed to mitigate the vulnerability"
|
|
||||||
fi
|
|
||||||
else
|
|
||||||
if [ "$kpti_support" = 1 ]; then
|
if [ "$kpti_support" = 1 ]; then
|
||||||
pvulnstatus CVE-2017-5754 OK "offline mode: PTI will mitigate the vulnerability if enabled at runtime"
|
pstatus green YES
|
||||||
|
elif [ "$kpti_can_tell" = 1 ]; then
|
||||||
|
pstatus red NO
|
||||||
else
|
else
|
||||||
pvulnstatus CVE-2017-5754 VULN "PTI is needed to mitigate the vulnerability"
|
pstatus yellow UNKNOWN "couldn't read your kernel configuration nor System.map file"
|
||||||
fi
|
fi
|
||||||
fi
|
|
||||||
|
|
||||||
_info
|
mount_debugfs
|
||||||
|
_info_nol "* PTI enabled and active: "
|
||||||
|
if [ "$opt_live" = 1 ]; then
|
||||||
|
if grep ^flags /proc/cpuinfo | grep -qw pti; then
|
||||||
|
# vanilla PTI patch sets the 'pti' flag in cpuinfo
|
||||||
|
kpti_enabled=1
|
||||||
|
elif grep ^flags /proc/cpuinfo | grep -qw kaiser; then
|
||||||
|
# kernel line 4.9 sets the 'kaiser' flag in cpuinfo
|
||||||
|
kpti_enabled=1
|
||||||
|
elif [ -e /sys/kernel/debug/x86/pti_enabled ]; then
|
||||||
|
# RedHat Backport creates a dedicated file, see https://access.redhat.com/articles/3311301
|
||||||
|
kpti_enabled=$(cat /sys/kernel/debug/x86/pti_enabled 2>/dev/null)
|
||||||
|
elif dmesg | grep -Eq 'Kernel/User page tables isolation: enabled|Kernel page table isolation enabled'; then
|
||||||
|
# if we can't find the flag, grep dmesg output
|
||||||
|
kpti_enabled=1
|
||||||
|
elif [ -r /var/log/dmesg ] && grep -Eq 'Kernel/User page tables isolation: enabled|Kernel page table isolation enabled' /var/log/dmesg; then
|
||||||
|
# if we can't find the flag in dmesg output, grep in /var/log/dmesg when readable
|
||||||
|
kpti_enabled=1
|
||||||
|
else
|
||||||
|
kpti_enabled=0
|
||||||
|
fi
|
||||||
|
if [ "$kpti_enabled" = 1 ]; then
|
||||||
|
pstatus green YES
|
||||||
|
else
|
||||||
|
pstatus red NO
|
||||||
|
fi
|
||||||
|
else
|
||||||
|
pstatus blue N/A "can't verify if PTI is enabled in offline mode"
|
||||||
|
fi
|
||||||
|
|
||||||
|
if ! is_cpu_vulnerable 3; then
|
||||||
|
pvulnstatus CVE-2017-5754 OK "your CPU vendor reported your CPU model as not vulnerable"
|
||||||
|
elif [ "$opt_live" = 1 ]; then
|
||||||
|
if [ "$kpti_enabled" = 1 ]; then
|
||||||
|
pvulnstatus CVE-2017-5754 OK "PTI mitigates the vulnerability"
|
||||||
|
else
|
||||||
|
pvulnstatus CVE-2017-5754 VULN "PTI is needed to mitigate the vulnerability"
|
||||||
|
fi
|
||||||
|
else
|
||||||
|
if [ "$kpti_support" = 1 ]; then
|
||||||
|
pvulnstatus CVE-2017-5754 OK "offline mode: PTI will mitigate the vulnerability if enabled at runtime"
|
||||||
|
else
|
||||||
|
pvulnstatus CVE-2017-5754 VULN "PTI is needed to mitigate the vulnerability"
|
||||||
|
fi
|
||||||
|
fi
|
||||||
|
}
|
||||||
|
|
||||||
|
# now run the checks the user asked for
|
||||||
|
if [ "$opt_variant1" = 1 -o "$opt_allvariants" = 1 ]; then
|
||||||
|
check_variant1
|
||||||
|
_info
|
||||||
|
fi
|
||||||
|
if [ "$opt_variant2" = 1 -o "$opt_allvariants" = 1 ]; then
|
||||||
|
check_variant2
|
||||||
|
_info
|
||||||
|
fi
|
||||||
|
if [ "$opt_variant3" = 1 -o "$opt_allvariants" = 1 ]; then
|
||||||
|
check_variant3
|
||||||
|
_info
|
||||||
|
fi
|
||||||
|
|
||||||
_info "A false sense of security is worse than no security at all, see --disclaimer"
|
_info "A false sense of security is worse than no security at all, see --disclaimer"
|
||||||
|
|
||||||
|
# this'll umount only if we mounted debugfs ourselves
|
||||||
|
umount_debugfs
|
||||||
|
|
||||||
|
# cleanup the temp decompressed config
|
||||||
[ -n "$dumped_config" ] && rm -f "$dumped_config"
|
[ -n "$dumped_config" ] && rm -f "$dumped_config"
|
||||||
|
|
||||||
if [ "$opt_batch" = 1 -a "$opt_batch_format" = "nrpe" ]; then
|
if [ "$opt_batch" = 1 -a "$opt_batch_format" = "nrpe" ]; then
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue