Subject: Re: [PATCH] chromium
To:     Russell Coker <russell@coker.com.au>,
        "selinux-refpolicy@vger.kernel.org" 
        <selinux-refpolicy@vger.kernel.org>
References: <20190128084648.GA5441@xev>
From:   Chris PeBenito <pebenito@ieee.org>
Message-ID: <743dd8f5-9288-8216-4551-b7a74fda3e6d@ieee.org>
Date:   Tue, 29 Jan 2019 18:53:54 -0500
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.3.0
MIME-Version: 1.0
In-Reply-To: <20190128084648.GA5441@xev>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: selinux-refpolicy-owner@vger.kernel.org
Precedence: bulk

On 1/28/19 3:46 AM, Russell Coker wrote:
> There are several nacl binaries that need labels.
> 
> Put an ifdef debian for some chromium paths.
> 
> Git policy misses chromium_role() lines, were they in another patch that was
> submitted at the same time?
> 
> I don't know what this is for but doesn't seem harmful to allow it:
> type=PROCTITLE msg=audit(28/01/19 19:31:42.361:3218) : proctitle=/bin/bash /usr/bin/google-chrome
> type=SYSCALL msg=audit(28/01/19 19:31:42.361:3218) : arch=x86_64 syscall=openat success=yes exit=3 a0=0xffffff9c a1=0x563328f7b590 a2=O_WRONLY|O_CREAT|O_TRUNC a3=0x1b6 items=0 ppid=5158 pid=5166 auid=test uid=test gid=test euid=test suid=test fsuid=test egid=test sgid=test fsgid=test tty=pts7 ses=232 comm=google-chrome exe=/bin/bash subj=user_u:user_r:chromium_t:s0 key=(null)
> type=AVC msg=audit(28/01/19 19:31:42.361:3218) : avc:  granted  { associate } for  pid=5166 comm=google-chrome name=63 scontext=user_u:object_r:chromium_t:s0 tcontext=system_u:object_r:proc_t:s0 tclass=filesystem
> type=AVC msg=audit(28/01/19 19:31:42.361:3218) : avc:  granted  { create } for  pid=5166 comm=google-chrome name=63 scontext=user_u:user_r:chromium_t:s0 tcontext=user_u:object_r:chromium_t:s0 tclass=file
> type=AVC msg=audit(28/01/19 19:31:42.361:3218) : avc:  granted  { add_name } for  pid=5166 comm=google-chrome name=63 scontext=user_u:user_r:chromium_t:s0 tcontext=user_u:user_r:chromium_t:s0 tclass=dir
> 
> Allow domain_use_interactive_fds() for running via ssh -X.
> 
> Allow managing xdg data, cache, and config.
> 
> Allow reading public data from apt and dpkg, probably from lsb_release or some
> other shell script.
> 
> How does the whold naclhelper thing work anyway?  I'm nervous about process
> share access involving chromium_sandbox_t, is that really what we want?
> 
> Added lots of other stuff like searching cgroup dirs etc.
> 
> 
> Index: refpolicy-2.20180701/policy/modules/apps/chromium.fc
> ===================================================================
> --- refpolicy-2.20180701.orig/policy/modules/apps/chromium.fc
> +++ refpolicy-2.20180701/policy/modules/apps/chromium.fc
> @@ -2,7 +2,7 @@
>   /opt/google/chrome/chrome_sandbox			--	gen_context(system_u:object_r:chromium_sandbox_exec_t,s0)
>   /opt/google/chrome/chrome-sandbox			--	gen_context(system_u:object_r:chromium_sandbox_exec_t,s0)
>   /opt/google/chrome/google-chrome			--	gen_context(system_u:object_r:chromium_exec_t,s0)
> -/opt/google/chrome/nacl_helper_bootstrap		--	gen_context(system_u:object_r:chromium_naclhelper_exec_t,s0)
> +/opt/google/chrome/nacl_.*				--	gen_context(system_u:object_r:chromium_naclhelper_exec_t,s0)
>   /opt/google/chrome/libudev.so.0					gen_context(system_u:object_r:lib_t,s0)
>   
>   /opt/google/chrome-beta/chrome				--	gen_context(system_u:object_r:chromium_exec_t,s0)
> @@ -19,9 +19,14 @@
>   /opt/google/chrome-unstable/nacl_helper_bootstrap	--	gen_context(system_u:object_r:chromium_naclhelper_exec_t,s0)
>   /opt/google/chrome-unstable/libudev.so.0			gen_context(system_u:object_r:lib_t,s0)
>   
> +ifdef(`distro_debian',`
> +/usr/lib/chromium/chromium				--	gen_context(system_u:object_r:chromium_exec_t,s0)
> +/usr/lib/chromium/chrome-sandbox			--	gen_context(system_u:object_r:chromium_sandbox_exec_t,s0)
> +', `
>   /usr/lib/chromium-browser/chrome			--	gen_context(system_u:object_r:chromium_exec_t,s0)
>   /usr/lib/chromium-browser/chrome_sandbox		--	gen_context(system_u:object_r:chromium_sandbox_exec_t,s0)
>   /usr/lib/chromium-browser/chrome-sandbox		--	gen_context(system_u:object_r:chromium_sandbox_exec_t,s0)
> +')
>   /usr/lib/chromium-browser/chromium-launcher\.sh		--	gen_context(system_u:object_r:chromium_exec_t,s0)
>   /usr/lib/chromium-browser/nacl_helper_bootstrap		--	gen_context(system_u:object_r:chromium_naclhelper_exec_t,s0)
>   
> Index: refpolicy-2.20180701/policy/modules/roles/staff.te
> ===================================================================
> --- refpolicy-2.20180701.orig/policy/modules/roles/staff.te
> +++ refpolicy-2.20180701/policy/modules/roles/staff.te
> @@ -82,6 +82,10 @@ ifndef(`distro_redhat',`
>   	')
>   
>   	optional_policy(`
> +		chromium_role(staff_r, staff_t)
> +	')
> +
> +	optional_policy(`
>   		cron_role(staff_r, staff_t)
>   	')
>   
> Index: refpolicy-2.20180701/policy/modules/roles/sysadm.te
> ===================================================================
> --- refpolicy-2.20180701.orig/policy/modules/roles/sysadm.te
> +++ refpolicy-2.20180701/policy/modules/roles/sysadm.te
> @@ -1272,6 +1272,10 @@ ifndef(`distro_redhat',`
>   	')
>   
>   	optional_policy(`
> +		chromium_role(sysadm_r, sysadm_t)
> +	')
> +
> +	optional_policy(`
>   		cron_admin_role(sysadm_r, sysadm_t)
>   	')
>   
> Index: refpolicy-2.20180701/policy/modules/roles/unprivuser.te
> ===================================================================
> --- refpolicy-2.20180701.orig/policy/modules/roles/unprivuser.te
> +++ refpolicy-2.20180701/policy/modules/roles/unprivuser.te
> @@ -50,6 +50,10 @@ ifndef(`distro_redhat',`
>   	')
>   
>   	optional_policy(`
> +		chromium_role(user_r, user_t)
> +	')
> +
> +	optional_policy(`
>   		cron_role(user_r, user_t)
>   	')
>   
> Index: refpolicy-2.20180701/policy/modules/apps/chromium.te
> ===================================================================
> --- refpolicy-2.20180701.orig/policy/modules/apps/chromium.te
> +++ refpolicy-2.20180701/policy/modules/apps/chromium.te
> @@ -78,6 +78,8 @@ xdg_cache_content(chromium_xdg_cache_t)
>   
>   # execmem for load in plugins
>   allow chromium_t self:process { execmem getsched getcap setcap setrlimit setsched sigkill signal };
> +allow chromium_t self:dir { write add_name };
> +allow chromium_t self:file create;

I dropped this and the related proc_t associate.  I would like to have a 
better understanding what is happening.  The domain type on 
file/dir/lnk_file is supposed to be exclusively for the the /proc/pid 
entries.  The domain shouldn't be creating files with this type.  The 
fact that it is creating it in proc is even weirder.

>   allow chromium_t self:fifo_file rw_fifo_file_perms;
>   allow chromium_t self:sem create_sem_perms;
>   allow chromium_t self:netlink_kobject_uevent_socket client_stream_socket_perms;
> @@ -94,11 +96,14 @@ allow chromium_t chromium_renderer_t:shm
>   allow chromium_t chromium_renderer_t:unix_dgram_socket { read write };
>   allow chromium_t chromium_renderer_t:unix_stream_socket { read write };
>   
> -allow chromium_t chromium_sandbox_t:unix_dgram_socket { read write };
> -allow chromium_t chromium_sandbox_t:unix_stream_socket { read write };
> +allow chromium_t chromium_sandbox_t:unix_dgram_socket { getattr read write };
> +allow chromium_t chromium_sandbox_t:unix_stream_socket { getattr read write };
>   
>   allow chromium_t chromium_naclhelper_t:process { share };
>   
> +# for self:file create
> +kernel_associate_proc(chromium_t)
> +
>   # tmp has a wide class access (used for plugins)
>   manage_files_pattern(chromium_t, chromium_tmp_t, chromium_tmp_t)
>   allow chromium_t chromium_tmp_t:file map;
> @@ -149,6 +154,7 @@ dev_rw_xserver_misc(chromium_t)
>   dev_map_xserver_misc(chromium_t)
>   
>   domain_dontaudit_search_all_domains_state(chromium_t)
> +domain_use_interactive_fds(chromium_t)
>   
>   files_list_home(chromium_t)
>   files_search_home(chromium_t)
> @@ -159,12 +165,17 @@ files_read_etc_files(chromium_t)
>   files_dontaudit_getattr_all_dirs(chromium_t)
>   
>   fs_dontaudit_getattr_xattr_fs(chromium_t)
> +fs_getattr_tmpfs(chromium_t)
> +fs_search_cgroup_dirs(chromium_t)
>   
>   miscfiles_read_all_certs(chromium_t)
>   miscfiles_read_localization(chromium_t)
>   
>   sysnet_dns_name_resolve(chromium_t)
>   
> +# for /run/udev/data/*
> +udev_read_pid_files(chromium_t)
> +
>   userdom_user_content_access_template(chromium, chromium_t)
>   userdom_dontaudit_list_user_home_dirs(chromium_t)
>   # Debugging. Also on user_tty_device_t if X is started through "startx" for instance
> @@ -172,12 +183,10 @@ userdom_use_user_terminals(chromium_t)
>   userdom_manage_user_certs(chromium_t)
>   userdom_user_home_dir_filetrans_user_cert(chromium_t, dir, ".pki")
>   
> -xdg_create_cache_dirs(chromium_t)
> -xdg_create_config_dirs(chromium_t)
> -xdg_create_data_dirs(chromium_t)
> +xdg_manage_cache(chromium_t)
> +xdg_manage_config(chromium_t)
> +xdg_manage_data(chromium_t)

It seems like it might be best to have chromium-specific 
cache/data/config if it is modifying them.

>   xdg_manage_downloads(chromium_t)
> -xdg_read_config_files(chromium_t)
> -xdg_read_data_files(chromium_t)
>   
>   xserver_user_x_domain_template(chromium, chromium_t, chromium_tmpfs_t)
>   
> @@ -195,6 +204,8 @@ tunable_policy(`chromium_rw_usb_dev',`
>   tunable_policy(`chromium_read_system_info',`
>   	kernel_read_kernel_sysctls(chromium_t)
>   	# Memory optimizations & optimizations based on OS/version
> +	kernel_read_crypto_sysctls(chromium_t)
> +	kernel_read_kernel_sysctls(chromium_t)
>   	kernel_read_system_state(chromium_t)
>   
>   	# Debugging (sys/kernel/debug) and device information (sys/bus and sys/devices).
> @@ -237,6 +248,13 @@ optional_policy(`
>   	')
>   ')
>   
> +optional_policy(`
> +	apt_read_cache(chromium_t)
> +	apt_read_db(chromium_t)
> +	dpkg_exec(chromium_t)
> +	dpkg_read_db(chromium_t)
> +')
> +
>   ifdef(`use_alsa',`
>   	optional_policy(`
>   		alsa_domain(chromium_t, chromium_tmpfs_t)
> @@ -309,23 +327,27 @@ allow chromium_sandbox_t chromium_t:dir
>   allow chromium_sandbox_t chromium_t:lnk_file read_lnk_file_perms;
>   allow chromium_sandbox_t chromium_t:file rw_file_perms;
>   
> -allow chromium_sandbox_t chromium_t:unix_stream_socket { read write };
> -allow chromium_sandbox_t chromium_t:unix_dgram_socket { read write };
> +allow chromium_sandbox_t chromium_t:unix_stream_socket { getattr read write };
> +allow chromium_sandbox_t chromium_t:unix_dgram_socket { getattr read write };
>   
>   kernel_list_proc(chromium_sandbox_t)
>   
>   domain_dontaudit_read_all_domains_state(chromium_sandbox_t)
> +domain_use_interactive_fds(chromium_sandbox_t)
>   
>   userdom_use_user_ptys(chromium_sandbox_t)
>   
>   chromium_domtrans(chromium_sandbox_t)
> +domtrans_pattern(chromium_sandbox_t, chromium_naclhelper_exec_t, chromium_naclhelper_t)
> +allow chromium_sandbox_t chromium_naclhelper_t:process share;
>   
>   ##########################################
>   #
>   # Chromium nacl helper local policy
>   #
>   
> -allow chromium_naclhelper_t chromium_t:unix_stream_socket { read write };
> +allow chromium_naclhelper_t chromium_t:unix_stream_socket { getattr read write };
> +allow chromium_naclhelper_t chromium_sandbox_t:unix_stream_socket { getattr read write };
>   
>   domain_mmap_low_uncond(chromium_naclhelper_t)
>   
> @@ -338,3 +360,6 @@ tunable_policy(`chromium_read_system_inf
>   	kernel_dontaudit_read_kernel_sysctl(chromium_naclhelper_t)
>   	kernel_dontaudit_read_system_state(chromium_naclhelper_t)
>   ')
> +
> +dev_read_sysfs(chromium_naclhelper_t)
> +dev_read_urand(chromium_naclhelper_t)
> Index: refpolicy-2.20180701/policy/modules/kernel/kernel.if
> ===================================================================
> --- refpolicy-2.20180701.orig/policy/modules/kernel/kernel.if
> +++ refpolicy-2.20180701/policy/modules/kernel/kernel.if
> @@ -2364,6 +2364,24 @@ interface(`kernel_rw_all_sysctls',`
>   
>   ########################################
>   ## <summary>
> +##	Associate a file to proc_t (/proc)
> +## </summary>
> +## <param name="domain">
> +##	<summary>
> +##	Domain allowed access.
> +##	</summary>
> +## </param>
> +## <rolecap/>
> +#
> +interface(`kernel_associate_proc',`
> +	gen_require(`
> +		type proc_t;
> +	')
> +	allow $1 proc_t:filesystem associate;
> +')
> +
> +########################################
> +## <summary>
>   ##	Send a kill signal to unlabeled processes.
>   ## </summary>
>   ## <param name="domain">

Otherwise merged.

-- 
Chris PeBenito