From d62352434213dadfc82b0a014177b8c783f9a3dc Mon Sep 17 00:00:00 2001 From: Agata Gruza Date: Tue, 12 Nov 2019 09:30:36 -0800 Subject: [PATCH] Added support for TAA related vulnerabilities --- README.md | 7 ++ spectre-meltdown-checker.sh | 140 ++++++++++++++++++++++++++++++++++-- 2 files changed, 143 insertions(+), 4 deletions(-) diff --git a/README.md b/README.md index 6c94a81..2cec98f 100644 --- a/README.md +++ b/README.md @@ -14,6 +14,7 @@ A shell script to tell if your system is vulnerable against the several "specula - CVE-2018-12130 [microarchitectural fill buffer data sampling (MFBDS)] aka 'ZombieLoad' - CVE-2018-12127 [microarchitectural load port data sampling (MLPDS)] aka 'RIDL' - CVE-2019-11091 [microarchitectural data sampling uncacheable memory (MDSUM)] aka 'RIDL' +- CVE-2019-11135 [TSX asynchronous abort] aka 'TAA' Supported operating systems: - Linux (all versions, flavors and distros) @@ -145,6 +146,12 @@ docker run --rm --privileged -v /boot:/boot:ro -v /dev/cpu:/dev/cpu:ro -v /lib/m - Mitigation: microcode update + kernel update making possible to protect various CPU internal buffers from unprivileged speculative access to data - Performance impact of the mitigation: low to significant +**CVE-2019-11135** TSX Asynchronous Abort (TAA) + + - Impact: Kernel + - Mitigation: microcode update + kernel update making possible to protect various CPU internal buffers from unprivileged speculative access to data + - Performance impact of the mitigation: low to significant + ## Understanding what this script does and doesn't 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. diff --git a/spectre-meltdown-checker.sh b/spectre-meltdown-checker.sh index 0557cbc..d47cda6 100755 --- a/spectre-meltdown-checker.sh +++ b/spectre-meltdown-checker.sh @@ -78,7 +78,7 @@ show_usage() --batch prometheus produce output for consumption by prometheus-node-exporter --variant VARIANT specify which variant you'd like to check, by default all variants are checked - VARIANT can be one of 1, 2, 3, 3a, 4, l1tf, msbds, mfbds, mlpds, mdsum + VARIANT can be one of 1, 2, 3, 3a, 4, l1tf, msbds, mfbds, mlpds, mdsum, taa can be specified multiple times (e.g. --variant 2 --variant 3) --cve [cve1,cve2,...] specify which CVE you'd like to check, by default all supported CVEs are checked --hw-only only check for CPU information, don't check for any variant @@ -157,7 +157,7 @@ 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 CVE-2018-12126 CVE-2018-12130 CVE-2018-12127 CVE-2019-11091' +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 CVE-2018-12126 CVE-2018-12130 CVE-2018-12127 CVE-2019-11091 CVE-2019-11135' # find a sane command to print colored messages, we prefer `printf` over `echo` # because `printf` behavior is more standard across Linux/BSD @@ -279,6 +279,7 @@ cve2name() CVE-2018-12130) echo "ZombieLoad, microarchitectural fill buffer data sampling (MFBDS)";; CVE-2018-12127) echo "RIDL, microarchitectural load port data sampling (MLPDS)";; CVE-2019-11091) echo "RIDL, microarchitectural data sampling uncacheable memory (MDSUM)";; + CVE-2019-11135) echo "Transactional Synchronization Extensions (TSX) Asynchronous Abort (TAA)";; *) echo "$0: error: invalid CVE '$1' passed to cve2name()" >&2; exit 255;; esac } @@ -300,6 +301,7 @@ _is_cpu_vulnerable_cached() CVE-2018-12130) return $variant_mfbds;; CVE-2018-12127) return $variant_mlpds;; CVE-2019-11091) return $variant_mdsum;; + CVE-2019-11135) return $variant_taa;; *) echo "$0: error: invalid variant '$1' passed to is_cpu_vulnerable()" >&2; exit 255;; esac } @@ -326,6 +328,7 @@ is_cpu_vulnerable() variant_mfbds='' variant_mlpds='' variant_mdsum='' + variant_taa='' if is_cpu_mds_free; then [ -z "$variant_msbds" ] && variant_msbds=immune @@ -335,6 +338,11 @@ is_cpu_vulnerable() _debug "is_cpu_vulnerable: cpu not affected by Microarchitectural Data Sampling" fi + if is_cpu_taa_free; then + [ -z "$variant_taa" ] && variant_taa=immune + _debug "is_cpu_vulnerable: cpu not affected by TSX Asynhronous Abort" + fi + if is_cpu_specex_free; then variant1=immune variant2=immune @@ -346,6 +354,7 @@ is_cpu_vulnerable() variant_mfbds=immune variant_mlpds=immune variant_mdsum=immune + variant_taa=immune elif is_intel; then # Intel # https://github.com/crozone/SpectrePoC/issues/1 ^F E5200 => spectre 2 not vulnerable @@ -528,6 +537,7 @@ is_cpu_vulnerable() [ "$variant_mfbds" = "immune" ] && variant_mfbds=1 || variant_mfbds=0 [ "$variant_mlpds" = "immune" ] && variant_mlpds=1 || variant_mlpds=0 [ "$variant_mdsum" = "immune" ] && variant_mdsum=1 || variant_mdsum=0 + [ "$variant_taa" = "immune" ] && variant_taa=1 || variant_taa=0 variantl1tf_sgx="$variantl1tf" # even if we are vulnerable to L1TF, if there's no SGX, we're safe for the original foreshadow [ "$cpuid_sgx" = 0 ] && variantl1tf_sgx=1 @@ -616,6 +626,27 @@ is_cpu_mds_free() return 1 } + +is_cpu_taa_free() +{ + # return true (0) if the CPU isn't affected by tsx asynchronnous aborts, false (1) if it does. + # There are three types of processors that do not require additional mitigations. + # 1. CPUs that do not support Intel TSX are not affected. + # 2. CPUs that enumerate IA32_ARCH_CAPABILITIES[TAA_NO] (bit 8)=1 are not affected. + # 3. CPUs that support Intel TSX and do not enumerate IA32_ARCH_CAPABILITIES[MDS_NO] (bit 5)=1 + # do not need additional mitigations beyond what is already required to mitigate MDS. + + if ! is_intel; then + return 0 + # is intel + elif [ "$capabilities_taa_no" = 0 ] || \ + [ "$rtm" = 0]; then + return 0 + fi + + return 1 +} + is_cpu_ssb_free() { # return true (0) if the CPU isn't affected by speculative store bypass, false (1) if it does. @@ -885,8 +916,9 @@ while [ -n "$1" ]; do mlpds) opt_cve_list="$opt_cve_list CVE-2018-12127"; opt_cve_all=0;; mdsum) opt_cve_list="$opt_cve_list CVE-2019-11091"; opt_cve_all=0;; l1tf) opt_cve_list="$opt_cve_list CVE-2018-3615 CVE-2018-3620 CVE-2018-3646"; opt_cve_all=0;; + taa) opt_cve_list="$opt_cve_list CVE-2019-11135"; opt_cve_all=0;; *) - echo "$0: error: invalid parameter '$2' for --variant, expected either 1, 2, 3, 3a, 4, msbds, mfbds, mlpds, mdsum, or l1tf" >&2; + echo "$0: error: invalid parameter '$2' for --variant, expected either 1, 2, 3, 3a, 4, msbds, mfbds, mlpds, mdsum, taa or l1tf" >&2; exit 255 ;; esac @@ -2477,6 +2509,22 @@ check_cpu() fi fi + if is_intel; then + _info " * TSX Asynchronous Abort" + _info_nol " * TSX support is available: " + read_cpuid 0x7 $EDX 11 1 1; ret=$? + if [ $ret -eq 0 ]; then + rtm=1 + pstatus green YES "TSX RTM feature bit" + elif [ $ret -eq 2 ]; then + rtm=-1 + pstatus yellow UNKNOWN "is cpuid kernel module available?" + else + rtm=0 + pstatus yellow NO + fi + fi + if is_intel; then _info " * Enhanced IBRS (IBRS_ALL)" _info_nol " * CPU indicates ARCH_CAPABILITIES MSR availability: " @@ -2494,6 +2542,7 @@ check_cpu() fi _info_nol " * ARCH_CAPABILITIES MSR advertises IBRS_ALL capability: " + capabilities_taa_no=-1 capabilities_mds_no=-1 capabilities_rdcl_no=-1 capabilities_ibrs_all=-1 @@ -2504,6 +2553,7 @@ check_cpu() pstatus yellow UNKNOWN elif [ "$cpuid_arch_capabilities" != 1 ]; then capabilities_rdcl_no=0 + capabilities_taa_no=0 capabilities_mds_no=0 capabilities_ibrs_all=0 capabilities_rsba=0 @@ -2536,6 +2586,7 @@ check_cpu() done capabilities=$val_cap_msr capabilities_rdcl_no=0 + capabilities_taa_no=0 capabilities_mds_no=0 capabilities_ibrs_all=0 capabilities_rsba=0 @@ -2549,7 +2600,8 @@ check_cpu() [ $(( capabilities >> 3 & 1 )) -eq 1 ] && capabilities_l1dflush_no=1 [ $(( capabilities >> 4 & 1 )) -eq 1 ] && capabilities_ssb_no=1 [ $(( capabilities >> 5 & 1 )) -eq 1 ] && capabilities_mds_no=1 - _debug "capabilities says rdcl_no=$capabilities_rdcl_no ibrs_all=$capabilities_ibrs_all rsba=$capabilities_rsba l1dflush_no=$capabilities_l1dflush_no ssb_no=$capabilities_ssb_no mds_no=$capabilities_mds_no" + [ $(( capabilities >> 8 & 1 )) -eq 1 ] && capabilities_taa_no=1 + _debug "capabilities says rdcl_no=$capabilities_rdcl_no ibrs_all=$capabilities_ibrs_all rsba=$capabilities_rsba l1dflush_no=$capabilities_l1dflush_no ssb_no=$capabilities_ssb_no mds_no=$capabilities_mds_no taa_no=$capabilities_taa_no" if [ "$capabilities_ibrs_all" = 1 ]; then if [ $cpu_mismatch -eq 0 ]; then pstatus green YES @@ -2612,6 +2664,15 @@ check_cpu() else pstatus yellow NO fi + + _info_nol " * CPU explicitly indicates not being vulnerable to TSX Asynchrnonous Abort (TAA_NO): " + if [ "$capabilities_taa_no" = -1 ]; then + pstatus yellow UNKNOWN + elif [ "$capabilities_taa_no" = 1 ]; then + pstatus green YES + else + pstatus yellow NO + fi fi _info_nol " * CPU supports Software Guard Extensions (SGX): " @@ -4650,6 +4711,77 @@ check_mds_linux() fi } + +################### +# TAA SECTION + +# Transactional Synchronization Extension (TSX) Asynchronous Abort +check_CVE_2019_11135() +{ + cve='CVE-2019-11135' + check_taa $cve +} + +# TSX Asynchronous Abort +check_taa() +{ + sys_interface_available=0 + + cve=$1 + _info "\033[1;34m$cve aka '$(cve2name "$cve")'\033[0m" + + if [ "$opt_live" != 1 ]; then + pstatus blue N/A "not testable in offline mode" + pvulnstatus $cve UNK + return + fi + + if ! is_cpu_vulnerable "$cve" ; then + # override status & msg in case CPU is not vulnerable after all + pvulnstatus $cve OK "your CPU vendor reported your CPU model as not vulnerable" + return + fi + if sys_interface_check '/sys/devices/system/cpu/vulnerabilities/tsx_async_abort'; then + # this kernel has the /sys interface, trust it over everything + sys_interface_available=1 + fi + + if [ "$sys_interface_available" = 1 ]; then + if grep -Eq 'Not affected' "/sys/devices/system/cpu/vulnerabilities/tsx_async_abort"; then + taa_mitigated=1 + elif grep -Eq 'Mitigation:' "/sys/devices/system/cpu/vulnerabilities/tsx_async_abort"; then + if grep -Eq '(SMT mitigated|disabled)' "/sys/devices/system/cpu/vulnerabilities/tsx_async_abort"; then + taa_mitigated=1 + else + #Simultaneous multi-threading (aka SMT or HyperThreading) is enabled. System may be vulnerable in some environments. + taa_mitigated=1 + _info_nol "* Disable SMT to have complete mitigation\n" + fi + elif grep -Eq 'Vulnerable' "/sys/devices/system/cpu/vulnerabilities/tsx_async_abort"; then + taa_mitigated=0 + _info_nol "* For more info check Linux kernel Documentation/admin-guide/hw-vuln/tsx_async_abort.rst\n" + else + taa_mitigated=-1 + fi + + if grep -Eq 'no microcode' "/sys/devices/system/cpu/vulnerabilities/tsx_async_abort"; then + taa_mitigated=0 + _info_nol "* CPU microcode is needed to mitigate the vulnerability\n" + fi + else + pstatus yellow UNKNOWN "can't find or interpret /sys/devices/system/cpu/vulnerabilities/tsx_async_abort" + taa_mitigated=-1 + fi + + if [ $taa_mitigated = 0 ];then + pvulnstatus $cve VULN + elif [ $taa_mitigated = 1 ]; then + pvulnstatus $cve OK + else + pvulnstatus $cve UNK "further action may be needed to mitigate this vulnerability. For more info check Linux kernel Documentation/admin-guide/hw-vuln/tsx_async_abort.rst" + fi +} + if [ "$opt_no_hw" = 0 ] && [ -z "$opt_arch_prefix" ]; then check_cpu check_cpu_vulnerabilities