Permission error when enabling firewall, android 4.3

Avast Mobile Security Avast Mobile Security for Android
1

I just updated my Samsung Galaxy Note 2 from android 4.1.2 to 4.3.
Now I get an error when enabling the firewall even though avast has root permission.
The error is: “Error applying firewall rules (exit code 1): klogctl:Permission denied”
What could be the cause for this? Samsungs (in)famous KNOX is not enabled.
Could it be the SE for android?

  • John
2

Hello,

the problem is your new custom rom. It’s kernel doesn’t include some features the firewall requires.
You’ll need to switch to a different ROM.

Merry Christmas,

Werner

3

Or may be, if it is official ROM, you can try to add some libraries and do some changes before flashing it to the device; there is no need (generaly) to switch to other ROM, you need to modify your kernel.

4

It is stock rom and stock kernel… And with my old galaxy s2, the klogctl error that would show when using a kernel that did not contain the right modules was something like ‘function missing’ not permission denied.

I changed SElinux for android status from enforcing to permissive, and that solved it…
So it is a permission issue introduced by SElinux for android…
The same permission error is introduced with other apps that needs root.

Dont know if avast needs to fix this, or if it is the superuser tools that implements the fix…

John

5

“Hello,
the problem is your new custom rom. It’s kernel doesn’t include some features the firewall requires.
You’ll need to switch to a different ROM.
Merry Christmas,
Werner”

Hello Werner,

you know that you lose the warranty if you install an other than the original SAMSUNG Firmware (ROM) ???

Why you give so stupid hints here?

Greetings

Matthias

6

Yes, SElinux from its nature can revoke any changes about iptables; we can try to implement some workarounds, but can not promise when … Anyway, thanks for this issue.