adding support for new /sys interface (#55)
* adding support for new /sys interface * fix(objdump): prefer -d instead of -D, some kernels crash objdump otherwise
This commit is contained in:
Stéphane Lesimple
GitHub
parent
56b67f8082
commit
62f8ed6f61
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@ -8,7 +8,7 @@
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#
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# Stephane Lesimple
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#
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VERSION=0.25
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VERSION=0.26
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# Script configuration
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show_usage()
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@ -33,7 +33,8 @@ show_usage()
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Options:
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--no-color Don't use color codes
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-v, --verbose Increase verbosity level
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--verbose, -v Increase verbosity level
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--no-sysfs Don't use the /sys interface even if present
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--batch text Produce machine readable output, this is the default if --batch is specified alone
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--batch json Produce JSON output formatted for Puppet, Ansible, Chef...
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--batch nrpe Produce machine readable output formatted for NRPE
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@ -86,6 +87,7 @@ opt_variant1=0
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opt_variant2=0
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opt_variant3=0
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opt_allvariants=1
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opt_no_sysfs=0
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nrpe_critical=0
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nrpe_unknown=0
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@ -95,13 +97,13 @@ __echo()
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{
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opt="$1"
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shift
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msg="$@"
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_msg="$@"
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if [ "$opt_no_color" = 1 ] ; then
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# strip ANSI color codes
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msg=$(/bin/echo -e "$msg" | sed -r "s/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[m|K]//g")
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_msg=$(/bin/echo -e "$_msg" | sed -r "s/\x1B\[([0-9]{1,2}(;[0-9]{1,2})?)?[m|K]//g")
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fi
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# explicitely call /bin/echo to avoid shell builtins that might not take options
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/bin/echo $opt -e "$msg"
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/bin/echo $opt -e "$_msg"
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}
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_echo()
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@ -250,6 +252,9 @@ while [ -n "$1" ]; do
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elif [ "$1" = "--no-color" ]; then
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opt_no_color=1
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shift
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elif [ "$1" = "--no-sysfs" ]; then
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opt_no_sysfs=1
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shift
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elif [ "$1" = "--batch" ]; then
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opt_batch=1
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opt_verbose=0
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@ -548,46 +553,83 @@ umount_debugfs()
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fi
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}
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sys_interface_check()
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{
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[ "$opt_live" = 1 -a "$opt_no_sysfs" = 0 -a -r "$1" ] || return 1
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_info_nol "* Checking wheter we're safe according to the /sys interface: "
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if grep -qi '^not affected' "$1"; then
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# Not affected
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status=OK
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pstatus green YES "kernel confirms that your CPU is unaffected"
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elif grep -qi '^mitigation' "$1"; then
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# Mitigation: PTI
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status=OK
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pstatus green YES "kernel confirms that the mitigation is active"
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elif grep -qi '^vulnerable' "$1"; then
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# Vulnerable
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status=VULN
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pstatus red NO "kernel confirms your system is vulnerable"
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else
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status=UNK
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pstatus yellow UNKNOWN "unknown value reported by kernel"
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fi
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msg=$(cat "$1")
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return 0
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}
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###################
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# SPECTRE VARIANT 1
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check_variant1()
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{
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_info "\033[1;34mCVE-2017-5753 [bounds check bypass] aka 'Spectre Variant 1'\033[0m"
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_info_nol "* Checking count of LFENCE opcodes in kernel: "
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status=0
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if [ -n "$vmlinux_err" ]; then
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pstatus yellow UNKNOWN "$vmlinux_err"
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status=UNK
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sys_interface_available=0
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msg=''
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if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/spectre_v1"; then
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# this kernel has the /sys interface, trust it over everything
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sys_interface_available=1
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else
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if ! which objdump >/dev/null 2>&1; then
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pstatus yellow UNKNOWN "missing 'objdump' tool, please install it, usually it's in the binutils package"
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# no /sys interface (or offline mode), fallback to our own ways
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_info_nol "* Checking count of LFENCE opcodes in kernel: "
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if [ -n "$vmlinux_err" ]; then
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msg="couldn't check ($vmlinux_err)"
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status=UNK
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pstatus yellow UNKNOWN
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else
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# here we disassemble the kernel and count the number of occurences of the LFENCE opcode
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# in non-patched kernels, this has been empirically determined as being around 40-50
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# in patched kernels, this is more around 70-80, sometimes way higher (100+)
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# v0.13: 68 found in a 3.10.23-xxxx-std-ipv6-64 (with lots of modules compiled-in directly), which doesn't have the LFENCE patches,
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# so let's push the threshold to 70.
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# TODO LKML patch is starting to dump LFENCE in favor of the PAUSE opcode, we might need to check that (patch not stabilized yet)
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nb_lfence=$(objdump -D "$vmlinux" | grep -wc lfence)
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if [ "$nb_lfence" -lt 70 ]; then
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pstatus red NO "only $nb_lfence opcodes found, should be >= 70"
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status=1
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if ! which objdump >/dev/null 2>&1; then
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msg="missing 'objdump' tool, please install it, usually it's in the binutils package"
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status=UNK
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pstatus yellow UNKNOWN
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else
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pstatus green YES "$nb_lfence opcodes found, which is >= 70"
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status=2
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# 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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nb_lfence=$(objdump -d "$vmlinux" | grep -wc lfence)
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if [ "$nb_lfence" -lt 70 ]; then
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msg="only $nb_lfence opcodes found, should be >= 70, heuristic to be improved when official patches become available"
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status=VULN
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pstatus yellow UNKNOWN
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else
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msg="$nb_lfence opcodes found, which is >= 70, heuristic to be improved when official patches become available"
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status=OK
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pstatus green YES
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fi
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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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pvulnstatus CVE-2017-5753 OK "your CPU vendor reported your CPU model as not vulnerable"
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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 ${vmlinux}";;
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1) pvulnstatus CVE-2017-5753 VULN 'heuristic to be improved when official patches become available';;
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2) pvulnstatus CVE-2017-5753 OK 'heuristic to be improved when official patches become available';;
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esac
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# if we have the /sys interface, don't even check is_cpu_vulnerable ourselves, the kernel already does it
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if [ "$sys_interface_available" = 0 ] && ! is_cpu_vulnerable 1; then
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# override status & msg in case CPU is not vulnerable after all
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msg="your CPU vendor reported your CPU model as not vulnerable"
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status=OK
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fi
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# report status
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pvulnstatus CVE-2017-5753 "$status" "$msg"
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}
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###################
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@ -595,153 +637,169 @@ check_variant1()
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check_variant2()
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{
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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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status=UNK
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sys_interface_available=0
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msg=''
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if sys_interface_check "/sys/devices/system/cpu/vulnerabilities/spectre_v2"; then
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# this kernel has the /sys interface, trust it over everything
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sys_interface_available=1
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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 [ $? -eq 0 ]; then
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pstatus green YES
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else
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pstatus red NO
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_info "* Mitigation 1"
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_info_nol "* Hardware (CPU microcode) support for mitigation: "
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if [ ! -e /dev/cpu/0/msr ]; then
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# try to load the module ourselves (and remember it so we can rmmod it afterwards)
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modprobe msr 2>/dev/null && insmod_msr=1
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fi
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fi
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if [ "$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 [ "$opt_live" = 1 ]; then
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mount_debugfs
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for ibrs_file in \
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/sys/kernel/debug/ibrs_enabled \
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/sys/kernel/debug/x86/ibrs_enabled \
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/proc/sys/kernel/ibrs_enabled; do
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if [ -e "$ibrs_file" ]; then
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# if the file is there, we have IBRS compiled-in
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# /sys/kernel/debug/ibrs_enabled: vanilla
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# /sys/kernel/debug/x86/ibrs_enabled: RedHat (see https://access.redhat.com/articles/3311301)
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# /proc/sys/kernel/ibrs_enabled: OpenSUSE tumbleweed
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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 [ $? -eq 0 ]; then
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pstatus green YES
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ibrs_supported=1
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ibrs_enabled=$(cat "$ibrs_file" 2>/dev/null)
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break
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fi
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done
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fi
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if [ "$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 [ "$ibrs_supported" != 1 ]; then
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pstatus red NO
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fi
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_info_nol "* IBRS enabled for Kernel space: "
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if [ "$opt_live" = 1 ]; then
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# 0 means disabled
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# 1 is enabled only for kernel space
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# 2 is enabled for kernel and user space
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case "$ibrs_enabled" in
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"") [ "$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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if [ "$opt_live" = 1 ]; then
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case "$ibrs_enabled" in
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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' "$opt_config"; then
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pstatus green YES
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retpoline=1
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else
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pstatus red NO
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fi
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else
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pstatus yellow UNKNOWN "couldn't read your kernel configuration"
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fi
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_info_nol "* Kernel compiled with a retpoline-aware compiler: "
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# Now check if the compiler used to compile the kernel knows how to insert retpolines in generated asm
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# For gcc, this is -mindirect-branch=thunk-extern (detected by the kernel makefiles)
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# See gcc commit https://github.com/hjl-tools/gcc/commit/23b517d4a67c02d3ef80b6109218f2aadad7bd79
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# In latest retpoline LKML patches, the noretpoline_setup symbol exists only if CONFIG_RETPOLINE is set
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# *AND* if the compiler is retpoline-compliant, so look for that symbol
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if [ -n "$opt_map" ]; then
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# look for the symbol
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if grep -qw noretpoline_setup "$opt_map"; then
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retpoline_compiler=1
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pstatus green YES "noretpoline_setup symbol found in System.map"
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else
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pstatus red NO
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fi
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elif [ -n "$vmlinux" ]; then
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# look for the symbol
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if which nm >/dev/null 2>&1; then
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# the proper way: use nm and look for the symbol
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if nm "$vmlinux" 2>/dev/null | grep -qw 'noretpoline_setup'; then
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retpoline_compiler=1
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pstatus green YES "noretpoline_setup found in vmlinux symbols"
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else
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pstatus red NO
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fi
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elif grep -q noretpoline_setup "$vmlinux"; then
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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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retpoline_compiler=1
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pstatus green YES "noretpoline_setup found in vmlinux"
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else
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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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mount_debugfs
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for ibrs_file in \
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/sys/kernel/debug/ibrs_enabled \
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/sys/kernel/debug/x86/ibrs_enabled \
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/proc/sys/kernel/ibrs_enabled; do
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if [ -e "$ibrs_file" ]; then
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# if the file is there, we have IBRS compiled-in
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# /sys/kernel/debug/ibrs_enabled: vanilla
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# /sys/kernel/debug/x86/ibrs_enabled: RedHat (see https://access.redhat.com/articles/3311301)
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# /proc/sys/kernel/ibrs_enabled: OpenSUSE tumbleweed
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pstatus green YES
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ibrs_supported=1
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ibrs_enabled=$(cat "$ibrs_file" 2>/dev/null)
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break
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fi
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done
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fi
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if [ "$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 [ "$ibrs_supported" != 1 ]; then
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pstatus red NO
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fi
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else
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pstatus yellow UNKNOWN "couldn't find your kernel image or System.map"
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_info_nol "* IBRS enabled for Kernel space: "
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if [ "$opt_live" = 1 ]; then
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# 0 means disabled
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# 1 is enabled only for kernel space
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# 2 is enabled for kernel and user space
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case "$ibrs_enabled" in
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"") [ "$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"
|
||||
fi
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_info_nol "* IBRS enabled for User space: "
|
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if [ "$opt_live" = 1 ]; then
|
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case "$ibrs_enabled" in
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"") [ "$ibrs_supported" = 1 ] && pstatus yellow UNKNOWN || pstatus red NO;;
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0 | 1) pstatus red NO;;
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2) pstatus green YES;;
|
||||
*) pstatus yellow UNKNOWN;;
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esac
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||||
else
|
||||
pstatus blue N/A "not testable in offline mode"
|
||||
fi
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||||
|
||||
_info "* Mitigation 2"
|
||||
_info_nol "* Kernel compiled with retpoline option: "
|
||||
# We check the RETPOLINE kernel options
|
||||
if [ -r "$opt_config" ]; then
|
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if grep -q '^CONFIG_RETPOLINE=y' "$opt_config"; then
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pstatus green YES
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retpoline=1
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else
|
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pstatus red NO
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fi
|
||||
else
|
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pstatus yellow UNKNOWN "couldn't read your kernel configuration"
|
||||
fi
|
||||
|
||||
_info_nol "* Kernel compiled with a retpoline-aware compiler: "
|
||||
# Now check if the compiler used to compile the kernel knows how to insert retpolines in generated asm
|
||||
# For gcc, this is -mindirect-branch=thunk-extern (detected by the kernel makefiles)
|
||||
# See gcc commit https://github.com/hjl-tools/gcc/commit/23b517d4a67c02d3ef80b6109218f2aadad7bd79
|
||||
# In latest retpoline LKML patches, the noretpoline_setup symbol exists only if CONFIG_RETPOLINE is set
|
||||
# *AND* if the compiler is retpoline-compliant, so look for that symbol
|
||||
if [ -n "$opt_map" ]; then
|
||||
# look for the symbol
|
||||
if grep -qw noretpoline_setup "$opt_map"; then
|
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retpoline_compiler=1
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pstatus green YES "noretpoline_setup symbol found in System.map"
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else
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||||
pstatus red NO
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||||
fi
|
||||
elif [ -n "$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 "$vmlinux" 2>/dev/null | grep -qw 'noretpoline_setup'; then
|
||||
retpoline_compiler=1
|
||||
pstatus green YES "noretpoline_setup found in vmlinux symbols"
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||||
else
|
||||
pstatus red NO
|
||||
fi
|
||||
elif grep -q noretpoline_setup "$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
|
||||
fi
|
||||
|
||||
if ! is_cpu_vulnerable 2; then
|
||||
# if we have the /sys interface, don't even check is_cpu_vulnerable ourselves, the kernel already does it
|
||||
if [ "$sys_interface_available" = 0 ] && ! is_cpu_vulnerable 2; then
|
||||
# override status & msg in case CPU is not vulnerable after all
|
||||
pvulnstatus CVE-2017-5715 OK "your CPU vendor reported your CPU model as not vulnerable"
|
||||
elif [ "$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"
|
||||
elif [ -z "$msg" ]; then
|
||||
# if msg is empty, sysfs check didn't fill it, rely on our own test
|
||||
if [ "$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
|
||||
pvulnstatus CVE-2017-5715 VULN "IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
|
||||
if [ "$ibrs_supported" = 1 ]; then
|
||||
pvulnstatus CVE-2017-5715 OK "offline mode: IBRS will mitigate the vulnerability if enabled at runtime"
|
||||
else
|
||||
pvulnstatus CVE-2017-5715 VULN "IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability"
|
||||
fi
|
||||
fi
|
||||
else
|
||||
if [ "$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
|
||||
pvulnstatus CVE-2017-5715 "$status" "$msg"
|
||||
fi
|
||||
}
|
||||
|
||||
|
|
@ -750,88 +808,105 @@ check_variant2()
|
|||
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
|
||||
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 "$vmlinux" ]; then
|
||||
# same as above but in case we don't have System.map and only vmlinux, look for the
|
||||
# nopti option that is part of the patch (kernel command line option)
|
||||
kpti_can_tell=1
|
||||
if ! which strings >/dev/null 2>&1; then
|
||||
pstatus yellow UNKNOWN "missing 'strings' tool, please install it, usually it's in the binutils package"
|
||||
else
|
||||
if strings "$vmlinux" | grep -qw nopti; then
|
||||
|
||||
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
|
||||
else
|
||||
_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
|
||||
fi
|
||||
fi
|
||||
fi
|
||||
|
||||
if [ "$kpti_support" = 1 ]; then
|
||||
pstatus green YES
|
||||
elif [ "$kpti_can_tell" = 1 ]; then
|
||||
pstatus red NO
|
||||
else
|
||||
pstatus yellow UNKNOWN "couldn't read your kernel configuration nor System.map file"
|
||||
fi
|
||||
|
||||
mount_debugfs
|
||||
_info_nol "* PTI enabled and active: "
|
||||
if [ "$opt_live" = 1 ]; then
|
||||
if grep ^flags /proc/cpuinfo | grep -qw pti; then
|
||||
# vanilla PTI patch sets the 'pti' flag in cpuinfo
|
||||
kpti_enabled=1
|
||||
elif grep ^flags /proc/cpuinfo | grep -qw kaiser; then
|
||||
# kernel line 4.9 sets the 'kaiser' flag in cpuinfo
|
||||
kpti_enabled=1
|
||||
elif [ -e /sys/kernel/debug/x86/pti_enabled ]; then
|
||||
# RedHat Backport creates a dedicated file, see https://access.redhat.com/articles/3311301
|
||||
kpti_enabled=$(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
|
||||
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_enabled" = 1 ]; then
|
||||
pstatus green YES
|
||||
else
|
||||
pstatus red NO
|
||||
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
|
||||
if strings "$vmlinux" | grep -qw nopti; then
|
||||
kpti_support=1
|
||||
fi
|
||||
fi
|
||||
fi
|
||||
else
|
||||
pstatus blue N/A "can't verify if PTI is enabled in offline mode"
|
||||
fi
|
||||
|
||||
if ! is_cpu_vulnerable 3; then
|
||||
pvulnstatus CVE-2017-5754 OK "your CPU vendor reported your CPU model as not vulnerable"
|
||||
elif [ "$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"
|
||||
pstatus green YES
|
||||
elif [ "$kpti_can_tell" = 1 ]; then
|
||||
pstatus red NO
|
||||
else
|
||||
pvulnstatus CVE-2017-5754 VULN "PTI is needed to mitigate the vulnerability"
|
||||
pstatus yellow UNKNOWN "couldn't read your kernel configuration nor System.map file"
|
||||
fi
|
||||
|
||||
mount_debugfs
|
||||
_info_nol "* PTI enabled and active: "
|
||||
if [ "$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
|
||||
fi
|
||||
|
||||
# if we have the /sys interface, don't even check is_cpu_vulnerable ourselves, the kernel already does it
|
||||
cve='CVE-2017-5754'
|
||||
if [ "$sys_interface_available" = 0 ] && ! is_cpu_vulnerable 3; then
|
||||
# override status & msg in case CPU is not vulnerable after all
|
||||
pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable"
|
||||
elif [ -z "$msg" ]; then
|
||||
# if msg is empty, sysfs check didn't fill it, rely on our own test
|
||||
if [ "$opt_live" = 1 ]; then
|
||||
if [ "$kpti_enabled" = 1 ]; then
|
||||
pvulnstatus $cve OK "PTI mitigates the vulnerability"
|
||||
else
|
||||
pvulnstatus $cve VULN "PTI is needed to mitigate the vulnerability"
|
||||
fi
|
||||
else
|
||||
if [ "$kpti_support" = 1 ]; then
|
||||
pvulnstatus $cve OK "offline mode: PTI will mitigate the vulnerability if enabled at runtime"
|
||||
else
|
||||
pvulnstatus $cve VULN "PTI is needed to mitigate the vulnerability"
|
||||
fi
|
||||
fi
|
||||
else
|
||||
pvulnstatus $cve "$status" "$msg"
|
||||
fi
|
||||
}
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue