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[Lord Shonus]

Keep in mind that I've been refusing to learn Linux for years because the cultists piss me off so much, so my linux skills are extremely rudimentary.


This sounds like what I want (giving no access to the group "Others", read only access to the system as a whole, and full access to my user), but I don't quite understand your explanation of how to go about it.

[wierd]

Sorry.. I guess I just assumed full linux literacy.

Ok.. Hmm How to say this with the least confusion..

By default, a group is created along with each user account, when they are created by the system. The following examples are lifted from my chromebook. (It is running an ubuntu variant, for clarity.)

If we do a "long list" in the home folder, we will get output like this:

Code: [Select]

chromebook@chromebook:~$ ls -ll
total 4525448
drwxrwxr-x  2 chromebook chromebook       4096 Jun  9 22:32 books
drwxr-xr-x  2 chromebook chromebook       4096 Jul 13 03:09 Desktop
drwxrwxr-x 11 chromebook chromebook       4096 Jul  3 06:44 df_linux
drwxr-xr-x  8 chromebook chromebook       4096 Jul  1 08:58 Documents
drwxrwxr-x  3 chromebook chromebook       4096 Jun 17 20:43 dosbox
drwxr-xr-x  5 chromebook chromebook       4096 Jul 10 05:48 Downloads
drwxrwxr-x  6 chromebook chromebook       4096 Jun  4 13:20 fuse-nfs-master
-rw-r--r--  1 root       root       4510416896 Jun 30 21:34 gmbc.iso
-rw-r--r--  1 root       root            73383 Jun 30 21:34 gmbc.log
drwxr-xr-x  2 chromebook chromebook       4096 Jun  3 03:13 Music
drwxrwxr-x  4 chromebook chromebook       4096 Jun  9 07:44 mycloudsrc
drwxrwxr-x  2 chromebook chromebook       4096 Jun  3 06:21 NAS
drwxr-xr-x  3 chromebook chromebook       4096 Jun 11 05:50 Pictures
drwxr-xr-x  2 chromebook chromebook       4096 Jun  3 03:13 Public
-rw-rw-r--  1 chromebook chromebook  215713080 Mar 25 07:28 setup_aquaria_2.0.0.1.exe
drwxr-xr-x  2 chromebook chromebook       4096 Jun  3 03:13 Templates
drwxr-xr-x  2 chromebook chromebook       4096 Jun  3 03:13 Videos


See how it says 'chromebook chromebook' like that?  That is because there is both a user (chromebook) and a group with the same name (chromebook) that were created when I set up the box. That group only has 1 member. My user account.

It is this situation that requires use to use chown.  chown stands for "Change owner". 

In a nutshell, we want to change all the ownership data for your files so that instead of pointing at this placeholder group the system created, we want to point it at a real group that we have set up for this. I called it DAEMONS in my example above. You can name it anything you want.

When you use chown, the command wants to know both the username for the new owner, and the group they belong to, to provision access. If we keep my examples, in my case, this would be 'chromebook' for the user, and 'DAEMONS' for the group-- so the command would look like this:

chown -R chromebook:DAEMONS *

Breaking it down, we are telling chown to change ownership recursively (-R), assigning ownership to the 'chromebook' user, and the 'DAEMONS' group, for all files (*).

This basically just changes the group membership defined for group access for all the files it finds, since we are keeping the same username as the owner.

We need to have a group named DAEMONS for that to work though. As I said, I assumed full linux literacy, when I probably shouldnt have.

To create a new group with no members, use the groupadd command. (will probably need to be run with root shell)

groupadd DAEMONS

then add all the user accounts used by the various system daemons to this group with usermod.

usermod -aG DAEMONS [usernameOfSystemDaemon]

To better explain the above, when you install system daemons on a linux box, the configure script for them creates both a limited user account, and a group container for each service.   You can get a full list of the user accounts on a system by reading /etc/passwd. We dont care about most of the stuff in that file, just the entries for the user accounts the system knows about.  For reference, mine looks like this:

Code: [Select]

chromebook@chromebook:~$ cat /etc/passwd
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
bin:x:2:2:bin:/bin:/usr/sbin/nologin
sys:x:3:3:sys:/dev:/usr/sbin/nologin
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/usr/sbin/nologin
man:x:6:12:man:/var/cache/man:/usr/sbin/nologin
lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin
mail:x:8:8:mail:/var/mail:/usr/sbin/nologin
news:x:9:9:news:/var/spool/news:/usr/sbin/nologin
uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin
proxy:x:13:13:proxy:/bin:/usr/sbin/nologin
www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin
backup:x:34:34:backup:/var/backups:/usr/sbin/nologin
list:x:38:38:Mailing List Manager:/var/list:/usr/sbin/nologin
irc:x:39:39:ircd:/var/run/ircd:/usr/sbin/nologin
gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/usr/sbin/nologin
nobody:x:65534:65534:nobody:/nonexistent:/usr/sbin/nologin
systemd-timesync:x:100:102:systemd Time Synchronization,,,:/run/systemd:/bin/false
systemd-network:x:101:103:systemd Network Management,,,:/run/systemd/netif:/bin/false
systemd-resolve:x:102:104:systemd Resolver,,,:/run/systemd/resolve:/bin/false
systemd-bus-proxy:x:103:105:systemd Bus Proxy,,,:/run/systemd:/bin/false
messagebus:x:104:108::/var/run/dbus:/bin/false
syslog:x:105:109::/home/syslog:/bin/false
_apt:x:106:65534::/nonexistent:/bin/false
ntp:x:107:113::/home/ntp:/bin/false
avahi-autoipd:x:108:114:Avahi autoip daemon,,,:/var/lib/avahi-autoipd:/bin/false
avahi:x:109:115:Avahi mDNS daemon,,,:/var/run/avahi-daemon:/bin/false
colord:x:110:118:colord colour management daemon,,,:/var/lib/colord:/bin/false
dnsmasq:x:111:65534:dnsmasq,,,:/var/lib/misc:/bin/false
pulse:x:112:119:PulseAudio daemon,,,:/var/run/pulse:/bin/false
hplip:x:113:7:HPLIP system user,,,:/var/run/hplip:/bin/false
rtkit:x:114:121:RealtimeKit,,,:/proc:/bin/false
saned:x:115:122::/var/lib/saned:/bin/false
usbmux:x:116:46:usbmux daemon,,,:/var/lib/usbmux:/bin/false
speech-dispatcher:x:117:29:Speech Dispatcher,,,:/var/run/speech-dispatcher:/bin/false
uuidd:x:118:123::/run/uuidd:/bin/false
chromebook:x:1000:1000:chromebook,,,:/home/chromebook:/bin/bash
sshd:x:119:65534::/var/run/sshd:/bin/bash
statd:x:120:65534::/var/lib/nfs:/bin/false
clamav:x:121:128::/var/lib/clamav:/bin/false

As you can see, there are quite a few special user accounts associated with system services. We need to add each one to our newly created DAEMONS group, so that when those processes run, then can get the read only access we are providing for them.  Just replace the [usernameOfSystemDaemon] field in my example with the username of the daemon you want to make a member of that group. eg 'clamav' if you want clamav to be able to read that volume. Do that for each daemon account you want to grant access. (pain in the ass, but yeah...)


After that, we need to set up the access itself. We do that with the chmod (change mode) command. I gave this example:

chmod -R g=r,o= *

Breaking it down, we are telling chmod to do the following: Change permissions mode recursively (-R), giving group access of read only (g=r), and others no access (o=) for all files (*).

Since your own user gets their access credentials through their user account, they will still have appropriate access through that side of things. (Our chmod example omits meddling with user level permissions completely, and leaves them alone. Only group and others lists get changed)

For system services that may need to access those files, we need to add the appropriate user accounts the system created for those services to the newly created DAEMONS group.

AND the last bit of the puzzle-- umask

This is what defines the default permissions assigned to freshly created files. I already linked to the relevant documentation.

[Lord Shonus]

That is much clearer. I won't be able to try it tonight, but it should work.

[milo christiansen]

@Arx: My monitor is a ViewSonic VX2263Smhl which cost about $130. It's a really nice, but basic, 1080p IPS display.

It doesn't have fancy features like gsync, but it is a cheap and rock-solid monitor. Great color, nice wide view angle (it is IPS after all).

[scourge728]

So, this laptop of mine keeps deciding to just disconnect from the internet, the wi-fi hasn't gone out (and the find a network thing still displays it) but clicking on it just has it fail to connect for some unknown reason, restarting the computer lets it reconnect and it only does it once in a day for some odd reason, my old laptops never had this problem, can someone explain why this happens and hopefully how to fix it? (if you need more information just ask (although explaining how to find the information would PROBABLY help, as I likely won't know how to find it on my own) oh and it's windows 10, although I'm pretty sure the thing was originally running windows 7 before I obtained it

[wierd]

What chipset is the wifi?  I have seen this happen frequently with Broadcom based wifi controllers. I suspect it has something to do with the binary firmware blob that must be loaded into the network card each and every time the system boots. I suspect the card garbles or corrupts the firmware blob inside its memory fairly reliably after so many hours of operation. Technically, disabling and re-enabling the card should fix it, since that reloads the driver (and thus reinitializes the card with a fresh copy of the blob, which lives in the driver), but again is only a temp fix.

I have had much better luck with Atheros and Marvel based chipset wifi, as those dont load the firmware into the device's memory from the driver. (The firmware is actual ROM, and is reliable.)

[scourge728]

Oddly enough, today it decided to turn off 3 times, which has never happened before, because of that, I tried the windows network troubleshoot thing again (as the last time didn't give me much) and it decided the router was the problem, which as far as IK is bull because there are at least 10 other wi-fi connected devices in my house, none of which have this problem

Also, how do I check the chipset?

[wierd]

Easiest way to be sure is to check the pci_ven number.  Open device manager, browse to the device, check its properties, and paste the "Device ID" string. I will look it up for you and tell you exactly what it is.

[scourge728]

I found a "Matching device ID" which is PCI\VEN_8086&DEV_1E03&CC_0106

EDIT: Unless you mean one of the 6ish other things labeled as chipsets

[wierd]

That is clearly an intel item, with ven_8086...

Yup, and intel Sata controller.  Not the wifi nic.

[scourge728]

I have no idea what that means

[wierd]

You gave me the PCI ID for your HDD's controller.  Not for your wifi card.  I cannot tell you what kind of wifi card you have without something to go on, and the best ID is the PCI ID.

The PCI ID string is divided into 3 major parts. The vendor (VEN_XXX),  the device ID (&DEV_XXXXX), and the subsystem ID (&SUBSYS__XXXX)

Each manufacturer has its uniquely identifiable vendor ID. Intel's vendor id is 8086. Whenever I see "PCI_ID&VEN_8086" I know that this is an Intel product.

[scourge728]

PCI\VEN_168C&DEV_0032&SUBSYS_662711AD
this is the network adapter (I'm not all that good with computers, despite using them all the time, the inside workings are foreign to me

[wierd]

AR9485 Wireless Network Adapter

That is an Atheros card.  Since atheros uses actual firmware, and not a software blob, this is something different.  Are you using windows 10? There seems to be a very large number of users reporting a very similar issue to yours, when using win10 and a specific driver version for this card.

https://answers.microsoft.com/en-us/windows/forum/windows_10-networking/qualcomm-atheros-ar9485-wifi-disconnects-randomly/bb7fd0ef-455d-4e1e-b973-6632791e0cc3

Loooooong thread.  Last posting suggests disabling power management on the device in device manager. ("allow computer to turn off the device for power saving" option needs to be unchecked).  I have seen no new posts for about a month since that last one.

Other potential sources of the headache are:

Microsoft's forced update policy breaks shit. (Who ever would have guessed...) It does this through either A) installing a very old driver, or B) does not cleanly install a windows update which breaks the driver for the card in some arcane way internally.

Toggling power management looks like a potentially easy fix, and all other proposed fixes in that thread are apparently a mixed bag.

[scourge728]

Amusingly enough, after looking around in the settings, I turned off that power option hoping it might help, guess it does 
I also already made it so the computer THINKS I'm on a metered connection, and thus doesn't try to auto-update