Description of problem:
SElinux denies access to passwd file which conflicts with 'DynamicUser' service option. That causes failure during the start of a unit that uses 'DynamicUser'.

Version-Release number of selected component (if applicable):
systemd: 239-1
selinux-policy: 3.14.2-25

How reproducible:
Every time.

Steps to Reproduce:
1. Enable unit with configured 'DynamicUser' - systemd-networkd in my case.

Actual results:
Unit fails to start.

Expected results:
Unit starts correctly.

Additional info:
Used workaraund:
# ausearch -c '(networkd)' --raw|audit2allow -M init-passwd
# semodule -X 300 -i init-passwd.pp

# cat init-passwd.te 

module init-passwd 1.0;

require {
	type init_t;
	type passwd_file_t;
	class file write;
}

#============= init_t ==============
allow init_t passwd_file_t:file write;