GDM: PAM: pam-cap.so not applying capabilities

[gormac]

Hi, not sure if this is the right place to ask, please redirect me otherwise.

I have auth required pam_cap.so in my /etc/pam.d/login script and the related cap_net_raw,cap_net_admin username capabilities added to /etc/security/capability.conf

This works fine under xfce on xubuntu 20.04 and ubuntu server 20.04 but seems to consistently not work on ubuntu 20.04 with gnome. I’m wondering if it could be gdm related.

I’ve added the auth required pam_cap.so to /etc/pam.d/common-auth (above the pam-permit entry) but still no joy seeing the capabilities added to the user in Terminal

I see

$ grep Cap /proc/$BASHPID/status
CapInh:	0000000000000000
CapPrm:	0000000000000000
CapEff:	0000000000000000
CapBnd:	0000003fffffffff
CapAmb:	0000000000000000

when I would expect to see

$ grep Cap /proc/$BASHPID/status
CapInh:	0000000000003000
CapPrm:	0000000000000000
CapEff:	0000000000000000
CapBnd:	0000003fffffffff
CapAmb:	0000000000000000

Nothing is showing up under syslog or /var/log/auth.log

Perhaps this is unrelated to gdm/gnome but it seems to be the only commonality where the problem exists.

Thoughts/Suggestions?