Re: [PATCH 4/7] selinux: Update policy to fix user/group settings

["Richard W.M. Jones" <rjones@redhat.com>]

On Wed, Aug 16, 2023 at 08:00:35AM +0200, Stefano Brivio wrote:
> Somehow most of this used to work on older kernels, but now we need
> to explicitly permit setuid, setgid, and setcap capabilities, as well
> as read-only access to passwd (as we support running under a given
> login name) and sssd library facilities.
> 
> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
> ---
>  contrib/selinux/passt.te | 7 +++++--
>  contrib/selinux/pasta.te | 8 ++++++--
>  2 files changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/contrib/selinux/passt.te b/contrib/selinux/passt.te
> index 5868a41..a0c0526 100644
> --- a/contrib/selinux/passt.te
> +++ b/contrib/selinux/passt.te
> @@ -49,7 +49,7 @@ require {
>  
>  	class netlink_route_socket { bind create nlmsg_read };
>  
> -	class capability sys_tty_config;
> +	class capability { sys_tty_config setuid setgid };
>  	class cap_userns { setpcap sys_admin sys_ptrace };
>  	class user_namespace create;
>  }
> @@ -89,10 +89,13 @@ logging_send_syslog_msg(passt_t)
>  allow syslogd_t self:cap_userns sys_ptrace;
>  
>  allow passt_t self:process setcap;
> -allow passt_t self:capability { sys_tty_config setpcap net_bind_service };
> +allow passt_t self:capability { sys_tty_config setpcap net_bind_service setuid setgid};
>  allow passt_t self:cap_userns { setpcap sys_admin sys_ptrace };
>  allow passt_t self:user_namespace create;
>  
> +auth_read_passwd_file(passt_t)
> +sssd_search_lib(passt_t)
> +
>  allow passt_t proc_net_t:file read;
>  allow passt_t net_conf_t:file { open read };
>  allow passt_t net_conf_t:lnk_file read;
> diff --git a/contrib/selinux/pasta.te b/contrib/selinux/pasta.te
> index 645ccee..28265dc 100644
> --- a/contrib/selinux/pasta.te
> +++ b/contrib/selinux/pasta.te
> @@ -79,6 +79,7 @@ require {
>  	type shell_exec_t;
>  	type init_t;
>  
> +	class capability { sys_tty_config setuid setgid };
>  	class cap_userns { setpcap sys_admin sys_ptrace net_bind_service net_admin };
>  	class user_namespace create;
>  }
> @@ -103,10 +104,13 @@ allow unconfined_t pasta_t : process transition ;
>  
>  init_daemon_domain(pasta_t, pasta_exec_t)
>  
> -allow pasta_t self:capability { setpcap net_bind_service sys_tty_config dac_read_search net_admin sys_resource };
> +allow pasta_t self:capability { setpcap net_bind_service sys_tty_config dac_read_search net_admin sys_resource setuid setgid };
>  allow pasta_t self:cap_userns { setpcap sys_admin sys_ptrace net_admin net_bind_service };
>  allow pasta_t self:user_namespace create;
>  
> +auth_read_passwd_file(pasta_t)
> +sssd_search_lib(pasta_t)
> +
>  allow pasta_t bin_t:file { execute execute_no_trans map };
>  allow pasta_t nsfs_t:file { open read };
>  
> @@ -162,7 +166,7 @@ allow pasta_t unconfined_t:dir search;
>  allow pasta_t unconfined_t:file read;
>  allow pasta_t unconfined_t:lnk_file read;
>  allow pasta_t passwd_file_t:file { getattr open read };
> -allow pasta_t self:process setpgid;
> +allow pasta_t self:process { setpgid setcap };
>  allow pasta_t shell_exec_t:file { execute execute_no_trans map };
>  
>  allow pasta_t sssd_var_lib_t:dir search;

Usual kind of SELinux churn as new features are added so:

Reviewed-by: Richard W.M. Jones <rjones@redhat.com>

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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