[gentoo-commits] proj/hardened-refpolicy:master commit in: policy/modules/services/

[Jason Zaman]

commit:     a5ee3e4cc8dcc31a8a91cda5bebe514c15c83556
Author:     Nicolas Iooss <nicolas.iooss <AT> m4x <DOT> org>
AuthorDate: Sun Dec 20 15:28:48 2015 +0000
Commit:     Jason Zaman <perfinion <AT> gentoo <DOT> org>
CommitDate: Sat Jan 30 17:02:52 2016 +0000
URL:        https://gitweb.gentoo.org/proj/hardened-refpolicy.git/commit/?id=a5ee3e4c

Label Xorg server binary correctly on Arch Linux

On Arch Linux, /usr/bin/Xorg is only a shell script which executes
/usr/lib/xorg-server/Xorg.wrap, which is a SUID binary wrapper around
/usr/lib/xorg-server/Xorg.

Even though Xorg.wrap is not a full X server, it reads X11 configuration
files, uses the DRM interface to detect KMS, etc. (cf.
http://cgit.freedesktop.org/xorg/xserver/tree/hw/xfree86/xorg-wrapper.c?id=xorg-server-1.18.0
for more details).  Therefore label it as xserver_exec_t.

This makes the following AVC appear:

    denied  { execute_no_trans } for  pid=927 comm="X"
    path="/usr/lib/xorg-server/Xorg.wrap" dev="dm-0" ino=3152592
    scontext=system_u:system_r:xserver_t
    tcontext=system_u:object_r:xserver_exec_t tclass=file

Allow /usr/bin/Xorg to execute Xorg.wrap with a can_exec statement.

 policy/modules/services/xserver.fc | 2 ++
 policy/modules/services/xserver.te | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/policy/modules/services/xserver.fc b/policy/modules/services/xserver.fc
index 5ef36fb..619bb9f 100644
--- a/policy/modules/services/xserver.fc
+++ b/policy/modules/services/xserver.fc
@@ -71,6 +71,8 @@ HOME_DIR/\.Xauthority.*	--	gen_context(system_u:object_r:xauth_home_t,s0)
 /usr/bin/Xorg		--	gen_context(system_u:object_r:xserver_exec_t,s0)
 
 /usr/lib/qt-.*/etc/settings(/.*)? gen_context(system_u:object_r:xdm_var_run_t,s0)
+/usr/lib/xorg-server/Xorg	--	gen_context(system_u:object_r:xserver_exec_t,s0)
+/usr/lib/xorg-server/Xorg\.wrap	--	gen_context(system_u:object_r:xserver_exec_t,s0)
 
 /usr/sbin/lightdm	--	gen_context(system_u:object_r:xdm_exec_t,s0)
 

diff --git a/policy/modules/services/xserver.te b/policy/modules/services/xserver.te
index 82b9501..09c79bb 100644
--- a/policy/modules/services/xserver.te
+++ b/policy/modules/services/xserver.te
@@ -827,6 +827,9 @@ manage_sock_files_pattern(xserver_t, xdm_tmp_t, xdm_tmp_t)
 allow xserver_t xkb_var_lib_t:lnk_file read;
 can_exec(xserver_t, xkb_var_lib_t)
 
+# Run Xorg.wrap
+can_exec(xserver_t, xserver_exec_t)
+
 # VNC v4 module in X server
 corenet_tcp_bind_vnc_port(xserver_t)