Dbus access denied when accessing org/freedesktop/ModemManager1/Modems/0

snap
1

Hi,

I was try to access org/freedesktop/ModemManager1/Modems/0 on Ubuntu Core system.

snap connections:

    Interface      Plug                             Slot                   Notes
    modem-manager  modem-manager:mmcli              modem-manager:service  -
    modem-manager  network-manager:modem-manager    modem-manager:service  -
    modem-manager  turftank-software:modem-manager  modem-manager:service  manual

    Interface              Plug                                   Slot                     Notes
    dbus                   network-manager:wpa                    -                        -
    firewall-control       network-manager:firewall-control       :firewall-control        -
    hardware-observe       network-manager:hardware-observe       :hardware-observe        -
    login-session-observe  network-manager:login-session-observe  :login-session-observe   -
    modem-manager          network-manager:modem-manager          modem-manager:service    -
    network                network-manager:network                :network                 -
    network-manager        network-manager:nmcli                  network-manager:service  -
    network-manager        turftank-software:network-manager      network-manager:service  manual
    network-observe        network-manager:network-observe        :network-observe         -
    network-setup-control  network-manager:network-setup-control  :network-setup-control   -
    network-setup-observe  network-manager:network-setup-observe  :network-setup-observe   -
    ppp                    network-manager:ppp                    :ppp                     -

I have connected the modem-manager plugs, network-manager plugs . But I always get access denied and the message:

ERROR:dbus.proxies:Introspect error on :1.5:/org/freedesktop/ModemManager1/Modems/0: dbus.exceptions.DBusException: org.freedesktop.DBus.Error.AccessDenied: Rejected send message, 7 matched rules; type=“method_call”, sender=":1.41" (uid=1000 pid=9852 comm=“python3 /snap/turftank-software/x29/opt/ros/snap/l” label=“snap.turftank-software.nm-server (complain)”) interface=“org.freedesktop.DBus.Introspectable” member=“Introspect” error name="(unset)" requested_reply=“0” destination=":1.5" (uid=0 pid=1321 comm="/snap/modem-manager/471/usr/sbin/ModemManager --fi" label=“snap.modem-manager.modemmanager (enforce)”)

There is no sugesstions displayed in snappy-debug. I tried running in dev-mode and the results were the same.

The exact same issue was posted on https://bugs.launchpad.net/snapd/+bug/1659272 .But the discussion stopped without a solution.

Any help would be helpful

2

Could you please also share the dmesg message when you try this?

3

Hi, This is what i got in dmesg after i run the command

  • [ 831.840451] aud> it: type=1400 audit(1645430322.139:141): apparmor=“DENIED” operation=“capable” profile="/snap/snapd/14982/usr/lib/snapd/snap-confine" pid=2624 comm=“snap-confine” capability=4 capname=“fsetid”

  • [ 838.102255] audit: type=1400 audit(1645430328.399:142): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2675 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 838.362458] audit: type=1400 audit(1645430328.659:143): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2676 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 838.496416] audit: type=1400 audit(1645430328.795:144): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2677 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 838.654819] audit: type=1400 audit(1645430328.951:145): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2686 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 838.831700] audit: type=1400 audit(1645430329.127:146): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2652 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 839.190295] audit: type=1400 audit(1645430329.487:147): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2652 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 839.285232] audit: type=1400 audit(1645430329.583:148): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2652 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 839.423337] audit: type=1400 audit(1645430329.719:149): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2652 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 839.493714] audit: type=1400 audit(1645430329.791:150): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2652 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 840.255352] audit: type=1400 audit(1645430330.551:151): apparmor=“ALLOWED” operation=“open” profile=“snap.turftank-software.nm-server” name="/home/ttank/" pid=2652 comm=“python3” requested_mask=“r” denied_mask=“r” fsuid=0 ouid=1000

  • [ 843.856802] kauditd_printk_skb: 5 callbacks suppressed

  • [ 843.856809] audit: type=1400 audit(1645430334.155:157): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.862383] audit: type=1400 audit(1645430334.159:158): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.868155] audit: type=1400 audit(1645430334.167:159): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.873740] audit: type=1400 audit(1645430334.171:160): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.883804] audit: type=1400 audit(1645430334.179:161): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.889400] audit: type=1400 audit(1645430334.187:162): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.894985] audit: type=1400 audit(1645430334.191:163): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.900403] audit: type=1400 audit(1645430334.199:164): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.906286] audit: type=1400 audit(1645430334.203:165): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

  • [ 843.923775] audit: type=1400 audit(1645430334.219:166): apparmor=“DENIED” operation=“ptrace” profile=“snap.network-manager.networkmanager” pid=1338 comm=“NetworkManager” requested_mask=“read” denied_mask=“read” peer=“snap.turftank-software.nm-server”

4

you seem to be running something that should be a server process (and should be operating as root) as actual user from your homedir while not having the home interface connected …

1 Like
5

Right, and to talk to modem-manager you actually need to be root.

6

Yeah, thanks its solved now :grin:

1 Like