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Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:16
by Dobeedoo
Hi,
Is there any official information from Debian about ongoing (hopefully) work to mitigate the Meltdown/Spectre vulnerabilities? What would be sensible action (if any) to take while waiting for an official mitigation? I have of course updated my system to latest, but according to the test script, its still vulnerable and needs further actions.

What have you guys done (so far) to secure your systems?

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:17
by Head_on_a_Stick

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:20
by Head_on_a_Stick
Dobeedoo wrote:What would be sensible action (if any) to take while waiting for an official mitigation?
Disable javascript and make sure that all of your packages are up to date.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:22
by bw123
Dobeedoo wrote:Hi,
<snip>
What have you guys done (so far) to secure your systems?
I moved all my ASCII nudes to an external drive.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:29
by Dobeedoo
[quote="Head_on_a_Stick"]Please post the output of

Code: Select all

grep -r . /sys/devices/system/cpu/vulnerabilities
I get the following after running the above command;

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/sys/devices/system/cpu/vulnerabilities/spectre_v2:Vulnerable: Minimal generic ASM retpoline
/sys/devices/system/cpu/vulnerabilities/spectre_v1:Vulnerable
/sys/devices/system/cpu/vulnerabilities/meltdown:Mitigation: PTI

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:32
by Head_on_a_Stick
^ Thanks!
Dobeedoo wrote:

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/sys/devices/system/cpu/vulnerabilities/spectre_v2:Vulnerable: Minimal generic ASM retpoline
That's interesting, both Alpine Linux and Debian are using minimal generic ASM whereas Arch Linux is using full retpoline.

The only real way to protect yourself is to throw away all of your defective CPUs and switch to something open instead :D

:arrow: https://riscv.org/

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:32
by stevepusser
Burned all electronic devices with loads of fire and moved into my bunker.

Maybe you have to be using the latest compilers to get full retpoline support.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:35
by bw123
oh man I think they got nmy girly pics!!

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$ grep -r . /sys/devices/system/cpu/vulnerabilities
grep: /sys/devices/system/cpu/vulnerabilities: No such file or directory
b17@themini:/sys/devices/cpu$ uname -a
Linux themini 4.9.0-5-amd64 #1 SMP Debian 4.9.65-3+deb9u2 (2018-01-04) x86_64 GNU/Linux


Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:40
by Dobeedoo
Head_on_a_Stick wrote:^ Thanks!
Dobeedoo wrote:

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/sys/devices/system/cpu/vulnerabilities/spectre_v2:Vulnerable: Minimal generic ASM retpoline
That's interesting, both Alpine Linux and Debian are using minimal generic ASM whereas Arch Linux is using full retpoline.

The only real way to protect yourself is to throw away all of your defective CPUs and switch to something open instead :D

:arrow: https://riscv.org/
LOL! That may be a little harsh, just bought a new one... but wonder if they'd take it back as defective, hehe... :) If I read the CVE's you posted links to correctly, they say "attack range: local", I suppose that means it can't be exploited from outside my computer/network (assuming my firewall does a descent job)?

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:46
by Dobeedoo
stevepusser wrote:Burned all electronic devices with loads of fire and moved into my bunker.

Maybe you have to be using the latest compilers to get full retpoline support.
Yes, I realize there is no "fix", or at least no easy one. If I got things right, everything needs to be recompiled with retpoline support. I chose Debian for its security thinking and being one of the more stable distributions I know of, so not really worried, but a bit security minded.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:53
by Head_on_a_Stick
Dobeedoo wrote:If I read the CVE's you posted links to correctly, they say "attack range: local", I suppose that means it can't be exploited from outside my computer/network
Yes, that's right but Firefox and Chrom{e,ium} and (and some video drivers, apparently) were able to be used as attack vectors (if javascript was enabled) but this did not apply to firefox-esr, which is nice.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 19:56
by Head_on_a_Stick
bw123 wrote:

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$ grep -r . /sys/devices/system/cpu/vulnerabilities
grep: /sys/devices/system/cpu/vulnerabilities: No such file or directory
AMD machine?

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-07 20:01
by bw123
Head_on_a_Stick wrote:
bw123 wrote:

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$ grep -r . /sys/devices/system/cpu/vulnerabilities
grep: /sys/devices/system/cpu/vulnerabilities: No such file or directory
AMD machine?
Both intel and amd lack a /sys/devices/system/cpu/vulnerabilities file or direcotry on 4.9.65-3+deb9u2 which is debian stretch latest stable kernel.

I don't know why you guys try and worry me so much, are you even using debian? Is this FUD? Is it SPAM? Are you just clueless or what? I don;t get it!!!!

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-08 10:24
by Lysander
Dobeedoo wrote:What have you guys done (so far) to secure your systems?
Nothing on my Debian setup, apart from lethargically invoking sudo apt update whenever I remember to.

My netbook [Slackware] runs an Atom N270 so is theoretically, and reportedly, immune. By reportedly, I mean that the output of spectre-meltdown-checker states such. Nevertheless, I still perform kernel updates when they are available.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-08 10:39
by Thorny
Lysander wrote: Nothing on my Debian setup, apart from lethargically invoking sudo apt update whenever I remember to.
I'm pedantic, but you probably already realise that. :-)

I'm fairly sure you mean you invoke apt update and then apt upgrade if called for.
Just so lurkers and the inexperienced are clear.

On distros that I don't boot every time I do the update/upgrade dance as soon as I boot up so they are up to date and I don't forget and risk security. I'm pretty sure you could even script that if you chose to.

Thanks for indulging me, or complain if you want to, I respect your intelligence.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-08 10:49
by Lysander
Thorny wrote:I'm pedantic, but you probably already realise that. :-)
I think each case of pedantry has contextual validity. When it comes to Linux-learning, specificity is definitely a good thing.
Thorny wrote:I'm fairly sure you mean you invoke apt update and then apt upgrade if called for.
Just so lurkers and the inexperienced are clear.
That is indeed what I mean, thanks for the clarification.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-08 12:16
by n_hologram
Lysander wrote:My netbook [Slackware] runs an Atom N270 so is theoretically, and reportedly, immune. By reportedly, I mean that the output of spectre-meltdown-checker states such.
Are you running a 32 or 64-bit kernel.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-08 14:57
by acewiza
I believe the most important Debian-specific remediation's will involve what kernels are showing up where and when.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-08 15:42
by Lysander
n_hologram wrote:Are you running a 32 or 64-bit kernel.
The N270 is 32bit only, so I am running a 32bit smp.

Re: Official Debian standpoint on Meltdown/Spectre

Posted: 2018-02-08 15:50
by n_hologram
I forgot that several atom processors are invulnerable, so I'm assuming yours is one. If so, correct me if I'm wrong, but I'm not sure the kernel makes much of a difference.