[security][ARP] arp_filter should probably be enabled for most interfaces

Bug Reports
1

REPRODUCIBILITY: yes
OS VERSION: 5.0.0.72
HARDWARE: xperia 10ii
UI LANGUAGE: n/a
REGRESSION: unknown

DESCRIPTION:

arp_filter is not enabled on the network interfaces of the phone, this causes network information to be leaked between networks the phone is connected to.

PRECONDITIONS:

None

STEPS TO REPRODUCE:

  1. Let your phone be connected to wifi and cellular at the same time

  2. Inspect the ARP tables of the firewall/router and you will find many entries from the phone related to the cellular network.

EXPECTED RESULT:

I should not see the (CGNAT) cellular data IP addresses of my phone in my routers ARP table.

ACTUAL RESULT:

Already described

MODIFICATIONS:

/proc/sys/net/ipv4/conf/*/arp_filter
Should probably all be set to 1.

ADDITIONAL INFORMATION:

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