[adb-support] apparmor profile does not grant read access for the file containing the serial number

[Ferenc Czumbil]

The serial file is one level deeper in the directory structure on my system.

# Allow reading the serial number of all the USB devices.
/sys/devices/**/usb*/*/serial r,

Should be

# Allow reading the serial number of all the USB devices.
/sys/devices/**/usb*/**/serial r,

Apparmor audit log:
Mar 24 19:00:26 acme kernel: audit: type=1400 audit(1553454026.960:14575): apparmor="DENIED" operation="open" profile="snap.scrcpy.adb" name="/sys/devices/pci0000:00/0000:00:14.0/usb1/1-2/1-2.3/serial" pid=5057 comm=64657669636520706F6C6C requested_mask="r" denied_mask="r" fsuid=1000 ouid=0

[Zygmunt Krynicki (zyga)]

The interface does intend to allow that but I see how the path encores more devices your system. It will likely contain a hub that was not present while we were developing the interface. I will address this shortly.

[Zygmunt Krynicki (zyga)]

This is now addressed in https://github.com/snapcore/snapd/pull/6646

[Zygmunt Krynicki (zyga)]

This has been merged in master. The next edge build of core should have this fix available for testing.