I want to make sure that I am protected against Spectre and Meltdown

General system Applications
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This is the first time I am trying to do this. I have installed the package called spectre-meltdown-checker from AUR. I am pasting the output here. Please tell me if I am properly protected. Also please mention what’s your opinion about this >> click here

$ sudo spectre-meltdown-checker 
[sudo] password for home: 
Spectre and Meltdown mitigation detection tool v0.44

Checking for vulnerabilities on current system
Kernel is Linux 5.12.19-hardened1-1-hardened #1 SMP PREEMPT Tue, 20 Jul 2021 17:48:41 +0000 x86_64
CPU is Intel(R) Core(TM) i3-6100 CPU @ 3.70GHz

Hardware check
* Hardware support (CPU microcode) for mitigation techniques
  * Indirect Branch Restricted Speculation (IBRS)
    * SPEC_CTRL MSR is available:  YES 
    * CPU indicates IBRS capability:  YES  (SPEC_CTRL feature bit)
  * Indirect Branch Prediction Barrier (IBPB)
    * PRED_CMD MSR is available:  YES 
    * CPU indicates IBPB capability:  YES  (SPEC_CTRL feature bit)
  * Single Thread Indirect Branch Predictors (STIBP)
    * SPEC_CTRL MSR is available:  YES 
    * CPU indicates STIBP capability:  YES  (Intel STIBP feature bit)
  * Speculative Store Bypass Disable (SSBD)
    * CPU indicates SSBD capability:  YES  (Intel SSBD)
  * L1 data cache invalidation
    * FLUSH_CMD MSR is available:  YES 
    * CPU indicates L1D flush capability:  YES  (L1D flush feature bit)
  * Microarchitectural Data Sampling
    * VERW instruction is available:  YES  (MD_CLEAR feature bit)
  * Enhanced IBRS (IBRS_ALL)
    * CPU indicates ARCH_CAPABILITIES MSR availability:  NO 
    * ARCH_CAPABILITIES MSR advertises IBRS_ALL capability:  NO 
  * CPU explicitly indicates not being vulnerable to Meltdown/L1TF (RDCL_NO):  NO 
  * CPU explicitly indicates not being vulnerable to Variant 4 (SSB_NO):  NO 
  * CPU/Hypervisor indicates L1D flushing is not necessary on this system:  NO 
  * Hypervisor indicates host CPU might be vulnerable to RSB underflow (RSBA):  NO 
  * CPU explicitly indicates not being vulnerable to Microarchitectural Data Sampling (MDS_NO):  NO 
  * CPU explicitly indicates not being vulnerable to TSX Asynchronous Abort (TAA_NO):  NO 
  * CPU explicitly indicates not being vulnerable to iTLB Multihit (PSCHANGE_MSC_NO):  NO 
  * CPU explicitly indicates having MSR for TSX control (TSX_CTRL_MSR):  NO 
  * CPU supports Transactional Synchronization Extensions (TSX):  NO 
  * CPU supports Software Guard Extensions (SGX):  YES 
  * CPU supports Special Register Buffer Data Sampling (SRBDS):  YES 
  * CPU microcode is known to cause stability problems:  NO  (family 0x6 model 0x5e stepping 0x3 ucode 0xea cpuid 0x506e3)
  * CPU microcode is the latest known available version:  YES  (latest version is 0xe2 dated 2020/07/14 according to builtin firmwares DB v165.20201021+i20200616)
* CPU vulnerability to the speculative execution attack variants
  * Vulnerable to CVE-2017-5753 (Spectre Variant 1, bounds check bypass):  YES 
  * Vulnerable to CVE-2017-5715 (Spectre Variant 2, branch target injection):  YES 
  * Vulnerable to CVE-2017-5754 (Variant 3, Meltdown, rogue data cache load):  YES 
  * Vulnerable to CVE-2018-3640 (Variant 3a, rogue system register read):  YES 
  * Vulnerable to CVE-2018-3639 (Variant 4, speculative store bypass):  YES 
  * Vulnerable to CVE-2018-3615 (Foreshadow (SGX), L1 terminal fault):  YES 
  * Vulnerable to CVE-2018-3620 (Foreshadow-NG (OS), L1 terminal fault):  YES 
  * Vulnerable to CVE-2018-3646 (Foreshadow-NG (VMM), L1 terminal fault):  YES 
  * Vulnerable to CVE-2018-12126 (Fallout, microarchitectural store buffer data sampling (MSBDS)):  YES 
  * Vulnerable to CVE-2018-12130 (ZombieLoad, microarchitectural fill buffer data sampling (MFBDS)):  YES 
  * Vulnerable to CVE-2018-12127 (RIDL, microarchitectural load port data sampling (MLPDS)):  YES 
  * Vulnerable to CVE-2019-11091 (RIDL, microarchitectural data sampling uncacheable memory (MDSUM)):  YES 
  * Vulnerable to CVE-2019-11135 (ZombieLoad V2, TSX Asynchronous Abort (TAA)):  NO 
  * Vulnerable to CVE-2018-12207 (No eXcuses, iTLB Multihit, machine check exception on page size changes (MCEPSC)):  YES 
  * Vulnerable to CVE-2020-0543 (Special Register Buffer Data Sampling (SRBDS)):  YES 

CVE-2017-5753 aka 'Spectre Variant 1, bounds check bypass'
* Mitigated according to the /sys interface:  YES  (Mitigation: usercopy/swapgs barriers and __user pointer sanitization)
* Kernel has array_index_mask_nospec:  YES  (1 occurrence(s) found of x86 64 bits array_index_mask_nospec())
* Kernel has the Red Hat/Ubuntu patch:  NO 
* Kernel has mask_nospec64 (arm64):  NO 
* Kernel has array_index_nospec (arm64):  NO 
> STATUS:  NOT VULNERABLE  (Mitigation: usercopy/swapgs barriers and __user pointer sanitization)

CVE-2017-5715 aka 'Spectre Variant 2, branch target injection'
* Mitigated according to the /sys interface:  YES  (Mitigation: Full generic retpoline, IBPB: conditional, IBRS_FW, STIBP: conditional, RSB filling)
* Mitigation 1
  * Kernel is compiled with IBRS support:  YES 
    * IBRS enabled and active:  YES  (for firmware code only)
  * Kernel is compiled with IBPB support:  YES 
    * IBPB enabled and active:  YES 
* Mitigation 2
  * Kernel has branch predictor hardening (arm):  NO 
  * Kernel compiled with retpoline option:  YES 
    * Kernel compiled with a retpoline-aware compiler:  YES  (kernel reports full retpoline compilation)
  * Kernel supports RSB filling:  YES 
> STATUS:  NOT VULNERABLE  (Full retpoline + IBPB are mitigating the vulnerability)

CVE-2017-5754 aka 'Variant 3, Meltdown, rogue data cache load'
* Mitigated according to the /sys interface:  YES  (Mitigation: PTI)
* Kernel supports Page Table Isolation (PTI):  YES 
  * PTI enabled and active:  YES 
  * Reduced performance impact of PTI:  YES  (CPU supports INVPCID, performance impact of PTI will be greatly reduced)
* Running as a Xen PV DomU:  NO 
> STATUS:  NOT VULNERABLE  (Mitigation: PTI)

CVE-2018-3640 aka 'Variant 3a, rogue system register read'
* CPU microcode mitigates the vulnerability:  YES 
> STATUS:  NOT VULNERABLE  (your CPU microcode mitigates the vulnerability)

CVE-2018-3639 aka 'Variant 4, speculative store bypass'
* Mitigated according to the /sys interface:  YES  (Mitigation: Speculative Store Bypass disabled via prctl and seccomp)
* Kernel supports disabling speculative store bypass (SSB):  YES  (found in /proc/self/status)
* SSB mitigation is enabled and active:  YES  (per-thread through prctl)
* SSB mitigation currently active for selected processes:  YES  (gsettings-helper iwd librewolf pulseaudio systemd-journald systemd-logind systemd-networkd systemd-resolved systemd-timesyncd udevadm upowerd xdg-dbus-proxy)
> STATUS:  NOT VULNERABLE  (Mitigation: Speculative Store Bypass disabled via prctl and seccomp)

CVE-2018-3615 aka 'Foreshadow (SGX), L1 terminal fault'
* CPU microcode mitigates the vulnerability:  YES 
> STATUS:  NOT VULNERABLE  (your CPU microcode mitigates the vulnerability)

CVE-2018-3620 aka 'Foreshadow-NG (OS), L1 terminal fault'
* Mitigated according to the /sys interface:  YES  (Mitigation: PTE Inversion; VMX: conditional cache flushes, SMT vulnerable)
* Kernel supports PTE inversion:  YES  (found in kernel image)
* PTE inversion enabled and active:  YES 
> STATUS:  NOT VULNERABLE  (Mitigation: PTE Inversion; VMX: conditional cache flushes, SMT vulnerable)

CVE-2018-3646 aka 'Foreshadow-NG (VMM), L1 terminal fault'
* Information from the /sys interface: Mitigation: PTE Inversion; VMX: conditional cache flushes, SMT vulnerable
* This system is a host running a hypervisor:  NO 
* Mitigation 1 (KVM)
  * EPT is disabled:  NO 
* Mitigation 2
  * L1D flush is supported by kernel:  YES  (found flush_l1d in /proc/cpuinfo)
  * L1D flush enabled:  YES  (conditional flushes)
  * Hardware-backed L1D flush supported:  YES  (performance impact of the mitigation will be greatly reduced)
  * Hyper-Threading (SMT) is enabled:  YES 
> STATUS:  NOT VULNERABLE  (this system is not running a hypervisor)

CVE-2018-12126 aka 'Fallout, microarchitectural store buffer data sampling (MSBDS)'
* Mitigated according to the /sys interface:  YES  (Mitigation: Clear CPU buffers; SMT vulnerable)
* Kernel supports using MD_CLEAR mitigation:  YES  (md_clear found in /proc/cpuinfo)
* Kernel mitigation is enabled and active:  YES 
* SMT is either mitigated or disabled:  NO 
> STATUS:  NOT VULNERABLE  (Your microcode and kernel are both up to date for this mitigation, and mitigation is enabled)

CVE-2018-12130 aka 'ZombieLoad, microarchitectural fill buffer data sampling (MFBDS)'
* Mitigated according to the /sys interface:  YES  (Mitigation: Clear CPU buffers; SMT vulnerable)
* Kernel supports using MD_CLEAR mitigation:  YES  (md_clear found in /proc/cpuinfo)
* Kernel mitigation is enabled and active:  YES 
* SMT is either mitigated or disabled:  NO 
> STATUS:  NOT VULNERABLE  (Your microcode and kernel are both up to date for this mitigation, and mitigation is enabled)

CVE-2018-12127 aka 'RIDL, microarchitectural load port data sampling (MLPDS)'
* Mitigated according to the /sys interface:  YES  (Mitigation: Clear CPU buffers; SMT vulnerable)
* Kernel supports using MD_CLEAR mitigation:  YES  (md_clear found in /proc/cpuinfo)
* Kernel mitigation is enabled and active:  YES 
* SMT is either mitigated or disabled:  NO 
> STATUS:  NOT VULNERABLE  (Your microcode and kernel are both up to date for this mitigation, and mitigation is enabled)

CVE-2019-11091 aka 'RIDL, microarchitectural data sampling uncacheable memory (MDSUM)'
* Mitigated according to the /sys interface:  YES  (Mitigation: Clear CPU buffers; SMT vulnerable)
* Kernel supports using MD_CLEAR mitigation:  YES  (md_clear found in /proc/cpuinfo)
* Kernel mitigation is enabled and active:  YES 
* SMT is either mitigated or disabled:  NO 
> STATUS:  NOT VULNERABLE  (Your microcode and kernel are both up to date for this mitigation, and mitigation is enabled)

CVE-2019-11135 aka 'ZombieLoad V2, TSX Asynchronous Abort (TAA)'
* Mitigated according to the /sys interface:  YES  (Not affected)
* TAA mitigation is supported by kernel:  YES  (found tsx_async_abort in kernel image)
* TAA mitigation enabled and active:  NO 
> STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

CVE-2018-12207 aka 'No eXcuses, iTLB Multihit, machine check exception on page size changes (MCEPSC)'
* Mitigated according to the /sys interface:  YES  (KVM: Mitigation: VMX disabled)
* This system is a host running a hypervisor:  NO 
* iTLB Multihit mitigation is supported by kernel:  YES  (found itlb_multihit in kernel image)
* iTLB Multihit mitigation enabled and active:  YES  (KVM: Mitigation: VMX disabled)
> STATUS:  NOT VULNERABLE  (this system is not running a hypervisor)

CVE-2020-0543 aka 'Special Register Buffer Data Sampling (SRBDS)'
* Mitigated according to the /sys interface:  YES  (Mitigation: Microcode)
* SRBDS mitigation control is supported by the kernel:  YES  (found SRBDS implementation evidence in kernel image. Your kernel is up to date for SRBDS mitigation)
* SRBDS mitigation control is enabled and active:  YES  (Mitigation: Microcode)
> STATUS:  NOT VULNERABLE  (Your microcode and kernel are both up to date for SRBDS mitigation control. Mitigation is enabled)

> SUMMARY: CVE-2017-5753:OK CVE-2017-5715:OK CVE-2017-5754:OK CVE-2018-3640:OK CVE-2018-3639:OK CVE-2018-3615:OK CVE-2018-3620:OK CVE-2018-3646:OK CVE-2018-12126:OK CVE-2018-12130:OK CVE-2018-12127:OK CVE-2019-11091:OK CVE-2019-11135:OK CVE-2018-12207:OK CVE-2020-0543:OK

Need more detailed information about mitigation options? Use --explain
A false sense of security is worse than no security at all, see --disclaimer
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Yes, you are protected by default, and it’s evident from output.

Well obviously hardware zero-day is unpatchable :laughing:

Also some mitigations of it reduces performance (depending on your hardware), it might be some CPU speed it might be SSD speed… :woozy_face:

Personally for home use i turn most or all of that crap off, as it’s really pointless and i want full speed of my machine, for servers though it’s another story :upside_down_face:

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@keybreak
That’s a relief. Thanks.

I am using Linux for a long time now but I never needed to run a server. So how is a server different in comparison to a desktop ? My understanding is a server is (a) headless & be there are one or more listening services which makes it mandatory for some ports to be in open state. Is this the correct definition of a server ?

So are you saying that if no ports are open & there are no listening services the threat of Spectre & Meltdown doesn’t apply to this scenario ?

I use my desktop for web browsing, streaming Youtube & playing local media which includes audio & video files which are on my hard drive. Personally I haven’t noticed any loss in performance whatsoever. Is the loss of performance only realized when doing stuff like video editing and such ?

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No what i mean is that on server you must do whatever you could to protect your stuff, coz it’s not as performance intensive to host a site or whatever.

It’s not like gaming, video-editing, 3D modeling and stuff a lot of us doing at home.

But if all you do is watching some Internet on your home PC - it doesn’t matter as well really, it’s not that you need to squeeze every inch of performance for that, also as i’ve said performance loss depends a lot on your particular hardware, some you may not notice because it’s not always obvious where to look - you’d need to know your system really well and benchmark the hell out of it.

For example i remember there were vulnerability connected to it not long ago, mitigation of which have reduced some Intel GPU performance in half :laughing: That’s…noticeable.

It’s much more complicated than that, but if you read more and more on that subject you’ll realize that all those scary Spectre / Meltdown vulnerabilities which are soon be counted in 3 digit numbers - are variations of same hardware zero day, how severe depends on your CPU.

It’s like patching a dam which is about to break with band-aid…A little counter-productive

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