From:   Dominick Grift <dac.override@gmail.com>
To:     "Sugar\, David" <dsugar@tresys.com>
Cc:     "selinux-refpolicy\@vger.kernel.org" 
        <selinux-refpolicy@vger.kernel.org>
Subject: Re: [PATCH 2/2 v2] pam_faillock creates files in /run/faillock
References: <20190106123358.18395-1-dsugar@tresys.com>
        <20190106123358.18395-2-dsugar@tresys.com>
Date:   Sun, 06 Jan 2019 13:47:26 +0100
In-Reply-To: <20190106123358.18395-2-dsugar@tresys.com> (David Sugar's message
        of "Sun, 6 Jan 2019 12:34:35 +0000")
Message-ID: <878szy7y1t.fsf@gmail.com>
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"Sugar, David" <dsugar@tresys.com> writes:

> These are changes needed when pam_fallock creates files in /run/faillock
> (which is labeled faillog_t).  sudo and xdm (and probably other domains)
> will create files in this directory for successful and failed login
> attempts.
>
> type=AVC msg=audit(1545153126.899:210): avc:  denied  { search } for pid=8448 comm="lightdm" name="faillock" dev="tmpfs" ino=39318 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:faillog_t:s0 tclass=dir permissive=1
> type=AVC msg=audit(1545153131.090:214): avc:  denied  { write } for pid=8448 comm="lightdm" name="faillock" dev="tmpfs" ino=39318 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:faillog_t:s0 tclass=dir permissive=1
> type=AVC msg=audit(1545153131.090:214): avc:  denied  { add_name } for pid=8448 comm="lightdm" name="dsugar" scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:faillog_t:s0 tclass=dir permissive=1
> type=AVC msg=audit(1545153131.090:214): avc:  denied  { create } for pid=8448 comm="lightdm" name="dsugar" scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:faillog_t:s0 tclass=file permissive=1
> type=AVC msg=audit(1545153131.091:215): avc:  denied  { setattr } for pid=8448 comm="lightdm" name="dsugar" dev="tmpfs" ino=87599 scontext=system_u:system_r:xdm_t:s0-s0:c0.c1023 tcontext=system_u:object_r:faillog_t:s0 tclass=file permissive=1
>
> type=AVC msg=audit(1545167205.531:626): avc:  denied  { search } for pid=8264 comm="sudo" name="faillock" dev="tmpfs" ino=35405 scontext=sysadm_u:sysadm_r:cleaner_applyconfig_sudo_t:s0-s0:c0.c1023 tcontext=system_u:object_r:faillog_t:s0 tclass=dir permissive=1
> type=AVC msg=audit(1545167205.531:627): avc:  denied  { write } for pid=8264 comm="sudo" name="faillock" dev="tmpfs" ino=35405 scontext=sysadm_u:sysadm_r:cleaner_applyconfig_sudo_t:s0-s0:c0.c1023 tcontext=system_u:object_r:faillog_t:s0 tclass=dir permissive=1
> type=AVC msg=audit(1545167205.531:627): avc:  denied  { add_name } for pid=8264 comm="sudo" name="root" scontext=sysadm_u:sysadm_r:cleaner_applyconfig_sudo_t:s0-s0:c0.c1023 tcontext=system_u:object_r:faillog_t:s0 tclass=dir permissive=1
> type=AVC msg=audit(1545167205.531:627): avc:  denied  { create } for pid=8264 comm="sudo" name="root" scontext=sysadm_u:sysadm_r:cleaner_applyconfig_sudo_t:s0-s0:c0.c1023 tcontext=sysadm_u:object_r:faillog_t:s0 tclass=file permissive=1
>
> Signed-off-by: Dave Sugar <dsugar@tresys.com>
> ---
>  policy/modules/admin/sudo.if       |  2 +-
>  policy/modules/services/xserver.te |  1 -
>  policy/modules/system/authlogin.if | 21 +++++++++++++++++++++
>  3 files changed, 22 insertions(+), 2 deletions(-)
>
> diff --git a/policy/modules/admin/sudo.if b/policy/modules/admin/sudo.if
> index 01f408ef..1c1fbe7b 100644
> --- a/policy/modules/admin/sudo.if
> +++ b/policy/modules/admin/sudo.if
> @@ -116,8 +116,8 @@ template(`sudo_role_template',`
>  	auth_run_chk_passwd($1_sudo_t, $2)
>  	# sudo stores a token in the pam_pid directory
>  	auth_manage_pam_pid($1_sudo_t)
> +	auth_use_pam($1_sudo_t)
>  	auth_pid_filetrans_pam_var_run($1_sudo_t, dir, "sudo")
> -	auth_use_nsswitch($1_sudo_t)
>  
>  	init_rw_utmp($1_sudo_t)
>  
> diff --git a/policy/modules/services/xserver.te b/policy/modules/services/xserver.te
> index cc717e7f..37fb2a71 100644
> --- a/policy/modules/services/xserver.te
> +++ b/policy/modules/services/xserver.te
> @@ -484,7 +484,6 @@ term_setattr_unallocated_ttys(xdm_t)
>  auth_domtrans_pam_console(xdm_t)
>  auth_manage_pam_pid(xdm_t)
>  auth_manage_pam_console_data(xdm_t)
> -auth_rw_faillog(xdm_t)
>  auth_write_login_records(xdm_t)
>  
>  # Run telinit->init to shutdown.
> diff --git a/policy/modules/system/authlogin.if b/policy/modules/system/authlogin.if
> index 9b5e0fe0..8d79af78 100644
> --- a/policy/modules/system/authlogin.if
> +++ b/policy/modules/system/authlogin.if
> @@ -47,6 +47,7 @@ interface(`auth_use_pam',`
>  	# for encrypted homedir
>  	dev_read_sysfs($1)
>  
> +	auth_create_faillog($1)

auth_create_faillog_files($1)
auth_rw_faillog($1)
auth_setattr_faillog_files($1)

>  	auth_domtrans_chk_passwd($1)
>  	auth_domtrans_upd_passwd($1)
>  	auth_dontaudit_read_shadow($1)
> @@ -744,6 +745,26 @@ interface(`auth_append_faillog',`
>  	allow $1 faillog_t:file append_file_perms;
>  ')
>  
> +########################################
> +## <summary>
> +##	Create fail log lock (in /run/faillock).
> +## </summary>
> +## <param name="domain">
> +##	<summary>
> +##	Domain allowed access.
> +##	</summary>
> +## </param>
> +#
> +interface(`auth_create_faillog',`
> +	gen_require(`
> +		type faillog_t;
> +	')
> +
> +	auth_rw_faillog($1)
> +	create_files_pattern($1, faillog_t, faillog_t)
> +	setattr_files_pattern($1, faillog_t, faillog_t)
> +')

interface name is not accurate: auth_create_faillog_files()
auth_rw_faillog does not belong here
setattr needs a seperate interface: auth_setattr_faillog_files()

> +
>  ########################################
>  ## <summary>
>  ##	Read and write the login failure log.

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Dominick Grift