Unsteady false positive W-002 on template type

[cgzones]

I am getting unsteady false positive warnings for the following template:

tmux.if:         37: (W): Type $1_tmux_t is used in interface but not required (W-002)
tmux.if:         38: (W): Type $1_tmux_t is used in interface but not required (W-002)
tmux.if:         46: (W): Type $1_tmux_t is used in interface but not required (W-002)
tmux.if:         48: (W): Type $1_tmux_t is used in interface but not required (W-002)
tmux.if:         50: (W): Type $1_tmux_t is used in interface but not required (W-002)
tmux.if:         52: (W): Type $1_tmux_t is used in interface but not required (W-002)
tmux.if:         53: (W): Type $1_tmux_t is used in interface but not required (W-002)
tmux.if:         63: (W): Type $1_tmux_t is used in interface but not required (W-002)

## <summary>terminal multiplexer.</summary>

#######################################
## <summary>
##	The role template for the tmux module.
## </summary>
## <param name="role_prefix">
##	<summary>
##	The prefix of the user role (e.g., user
##	is the prefix for user_r).
##	</summary>
## </param>
## <param name="user_role">
##	<summary>
##	The role associated with the user domain.
##	</summary>
## </param>
## <param name="user_domain">
##	<summary>
##	The type of the user domain.
##	</summary>
## </param>
#
template(`tmux_role_template',`
	gen_require(`
		attribute tmux_domain;
		type tmux_exec_t, tmux_session_t;
		type tmux_home_t;
	')

	########################################
	#
	# Declarations
	#

	type $1_tmux_t, tmux_domain;
	userdom_user_application_domain($1_tmux_t, tmux_exec_t)    # line 37
	domain_interactive_fd_object($1_tmux_t)
	role $2 types $1_tmux_t;

	########################################
	#
	# Role dependent policy
	#

	domtrans_pattern($3, tmux_exec_t, $1_tmux_t)    # line 46

	admin_process_pattern($3, $1_tmux_t)

	allow $1_tmux_t $3:process signal;
	# read /proc/PID/cmdline
	allow $1_tmux_t $3:dir search_dir_perms;
	allow $1_tmux_t $3:file read_file_perms;

	allow $3 tmux_session_t:dir { manage_dir_perms relabel_dir_perms };
	allow $3 tmux_session_t:file { manage_file_perms relabel_file_perms };
	allow $3 tmux_session_t:sock_file { manage_sock_file_perms relabel_sock_file_perms };

	allow $3 tmux_home_t:dir { manage_dir_perms relabel_dir_perms };
	allow $3 tmux_home_t:file { manage_file_perms relabel_file_perms };
	allow $3 tmux_home_t:lnk_file { manage_lnk_file_perms relabel_lnk_file_perms };

	corecmd_shell_domtrans($1_tmux_t, $3)

	userdom_user_home_dir_filetrans($3, tmux_home_t, file, ".tmux.conf")
')
[...]

It happened first only on a laptop (with the same os, toolchain etc.), but now also on a gitlab-ci job (https://salsa.debian.org/cgzones-guest/selinux-policy-debian/-/jobs/606046).

It is not triggered by similar templates for sshd or su.

[dburgener]

I think this would occur if tmux_role_template is called from an interface elsewhere, which it looks like is the case of the linked policy. tmux_role_template is called by userdom_default_user_perms, which is listed as an interface. It looks like that was changed from a template to an interface fairly recently (12d3bb1a), which could potentially be the cause for apparently inconsistent behavior if some runs were on older versions of the policy?

I'll work on a fix for this situation. It might also make sense to add a style check for interfaces calling templates.

[cgzones]

Ah, Thanks!
Not calling the template from an interface seems to fix the issue.

It might also make sense to add a style check for interfaces calling templates.

+1

[cgzones]

see #50