phablet user part of the 'radio' group

[Jamie Strandboge]

The phablet user is part of the 'radio' group:
$ grep radio /etc/group
radio:x:1001:phablet

This is corresponds to android's AID_RADIO id, which gives access to the telephony subsystem, RIL (system/core/include/private/android_filesystem_config.h). In Ubuntu Touch, the following directories:
/var/lib/lxc/android/rootfs/data/misc/sms drwxrwx--- system radio
/var/lib/lxc/android/rootfs/data/radio drwxrwx--- radio radio

Furthermore, in 14.04 we have (on flo):
/dev/diag crw-rw---- radio radio
/dev/rmnet_mux_ctrl crw-r----- radio radio
/dev/smdcntl0 crw-r----- radio radio
/dev/smdcntl1 crw-r----- radio radio
/dev/smdcntl2 crw-r----- radio radio
/dev/smdcntl3 crw-r----- radio radio
/dev/smdcntl4 crw-r----- radio radio
/dev/smdcntl5 crw-r----- radio radio
/dev/smdcntl6 crw-r----- radio radio
/dev/smdcntl7 crw-r----- radio radio
/dev/socket/qmux_radio drwxrws--- radio radio
/dev/socket/qmux_radio/qmux_client_socket\ srw-rw---- radio radio
/proc/cmdline -r--r----- root radio
/var/lib/lxc/android/rootfs/data/misc/radio drwxrwx--- system radio
/var/lib/lxc/android/rootfs/data/misc/sms drwxrwx--- system radio
/var/lib/lxc/android/rootfs/dev/alarm crw-rw-r-- system radio
/var/lib/lxc/android/rootfs/dev/diag crw-rw---- radio radio
/var/lib/lxc/android/rootfs/dev/qmi0 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/qmi1 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/qmi2 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/rmnet_mux_ctrl crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smd7 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smdcntl0 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smdcntl1 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smdcntl2 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smdcntl3 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smdcntl4 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smdcntl5 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smdcntl6 crw-r----- radio radio
/var/lib/lxc/android/rootfs/dev/smdcntl7 crw-r----- radio radio
/var/lib/lxc/android/rootfs/socket/qmux_radio drwxrws--- radio radio
/var/lib/lxc/android/rootfs/socket/qmux_radio/qmux_client_socket\ srw-rw---- radio radio

It seems that the phablet user may not be required to by in this group since system services like ofono should be handling this for the user. Please either adjust for the phablet user to not be required in the 'radio' group or describe why it is needed and not a problem.

Thanks!

[Jamie Strandboge (jdstrand)]

Any news on this?

[Tony Espy (awe)]

Confirmed.

At one point we 'd removed the user 'radio' check in the rild wrapper library ( the open components of rild ):

https://code-review.phablet.ubuntu.com/gitweb?p=CyanogenMod/android_hardware_ril.git;a=commitdiff;h=a95f74b45ea801f14b1aaa78707cf691de82c76c

However when we moved from Cyanogen back to AOSP, we dropped this patch:

https://code-review.phablet.ubuntu.com/gitweb?p=aosp/platform/hardware/ril.git;a=blob;f=libril/ril.cpp;h=19579393e1c550d4aae23bebf13d96dd558ba799;hb=865ce3b4a2ba0b3a31421ca671f4d6c5595f8690

...and correspondingly made ofono use setgid/uid to assume the RADIO user's group and user IDs:

https://github.com/rilmodem/ofono/blob/master/gril/gril.c#L870

There's a possibility that NM need's access to these directories, however that's the only explanation I can think of...

[Mathieu Trudel-Lapierre (cyphermox)]

I don't see anythere there that would be required by NetworkManager. Go from me to remove this.

[Alfonso Sanchez-Beato (alfonsosanchezbeato)]

It is not required by ofono either. Removing it did not apparently break anything from the telephony side.