Output errors

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Hello

I was going to add this to an older thread but got told to make a new one… so here we go!

Pre-amble:
System: i386, GNU/Linux Debian Squeeze.
Version: avast! Linux Home Edition version 1.3.0
VPS Version: 120521-0, 21/05/12
Initially I could not get avast to run as (form the application menu), until I read those posts about editing /etc/init.d/rcS - Thank you (http://forum.avast.com/index.php?topic=57775.0).
Running avast as root/super-user/whatever ground my system to a halt because the /root directory swelled to 100%.
Eventually I got avast to execute from …

Just done first scan and then looked through the output. There are quite a lot of errors.
(a) Permission denied,
(b) Operation not permitted,
(c) Input/output error,
(d) Decompression bomb,
(e) Corrupt zip.

Re (a) Permissions.
I looked at the other threads on this (http://forum.avast.com/index.php?topic=61474.msg520317#msg520317 and others).
Just to be clear …
When using a Unix -based or -like system, there is nothing to worry about regarding all the files that have “permission denied” in the output log, which are in directories higher than /home/, i.e. those that need root-access to edit?
Why?

  • I do understand the way permissions work but it would seem sensible than anti-virus software would have access all areas, no?
  • is it because a virus could never have access to these files either?
  • surely the problem with a virus is that it can “go around” normal security features, isn’t it?
  • based on my experience, running avast as “root” is not a good idea!

Re (b) Operation not permitted
How is this different to (a)?

Re (c) I/O

  • what does this mean?

Re (d) Compression bomb

  • what’s the problem with compressed files/folders?
  • can’t viri lurk in these too?

Re (e) Corrupt zip files

  • can’t Avast! search “corrupt” files?
  • the object it’s highlighting isn’t a zip either, it’s an image within a document; the document is in a s sub-directory of /usr/share.

I have read a few posts on the matter like http://forum.avast.com/index.php?topic=61013.msg560969#msg560969. However, it would be good to know, in each case, how can the error output be reduced/prevented?

The other thing is: on re-starting the GUI, the software cannot detect the error-report even though it’s in the correct directory. I had to use GEdit, which is fine but it would be best to view reports using the avast viewer. Any ideas? Fixed - my bad! OTH, mouse-scroll doesn’t work.

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e) as i know, a boot scan will identify every corrupt zip file.

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…mmm so run avast when booting? Or do you mean a system boot-scan?

Ideas about reducing a, b, c or d gratefully received?

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Hi demolition. :slight_smile:

...mmm so run avast when booting? Or do you mean a system boot-scan?

Ideas about reducing a, b, c or d gratefully received?


The Boot time Scan is a feature of Avast! for Windows, not Linux version.

Linux is not vulnerable to Malware like say a MS Operating System, so Avast! for
Linux works differently.

You have raised the issue of scanning the root directory. This is the strength of Linux Distros, and you are seeing it first hand.

  1. Not only can Avast! not scan those exceptions you have listed, but no Virus
    can either. That’s a good thing !!

  2. Therefore the results actually testify to the strengths of Linux. If you were silly, no insult implied, you could change the permissions of your / (root) Directory to that of the User, then Avast! would have access to scan those System Files, but you would also be opening the door to viruses to have access to those root files, or also Bork your System.

  3. Running avast as root/super-user/whatever ground my system to a halt

because the /root directory swelled to 100%.
Another example of the / (root directory) closing out unwanted probing by what it sees as a foreign body. Never Login as root. Please don’t use SUDO, unless you are quickly changing a system setting which requires it, “su” is much safer in any case. I don’t have time to explain why SUDO is a risk, it just is.
OK, look and read here, all will become clear: https://help.ubuntu.com/community/RootSudo

In Linux (and Unix in general), there is a SuperUser named Root. The Windows equivalent of Root is Administrators group. The SuperUser can do anything and everything, and thus doing daily work as the SuperUser can be dangerous. You could type a command incorrectly and destroy the system. Ideally, you run as a user that has only the privileges needed for the task at hand. In some cases, this is necessarily Root, but most of the time it is a regular user.
NEVER use[b] root/super-user/[/b] to run Avast! As you see it wont work for security reasons, plus Avast! 4Linux isn't built to be used in that fashion. It scans important files Avast! expert programmer's believe to be dynamic to the Linux System.

You may have a MS Window’s mentallity; no insult implied, that ALL files should be scanned to feel the Scan is successful. Not so, due to the permissions imposed on / (root) files. Permissions imposed to protect such files as those displayed as unable to be scanned in the OUTPUT at the end of a Scan.

4.I get the same unscanned ‘protected files’ result. It is no big deal. Same can happen in Windows to a few protected System files.
This ‘output’ is not necessarily an ERROR, as you perceive it, but as the syntax (wording) that Avast! uses to describe the event. OK ?

  1. When the scan finishes look at what has been displayed as not being able to be scanned, and the short decsription why, out of interest. From what you’ve now read I hope you understand this is not a problem, but information for the User.
    Then look at the Avast! GUI, and see were it says, " Number of infected Files".
    That’s what you should worry about. It will say; “No Infected Files”, hopefully.     :wink:

Hope that helps :wink:


Edited by Abraxas: spelling error.