From 3dad7b611a448fa43a678ff760c23a00f387947e Mon Sep 17 00:00:00 2001 From: Stephen Smalley Date: Wed, 5 Mar 2014 09:50:08 -0500 Subject: [PATCH] Address system_server denials. Label /proc/sysrq-trigger and allow access. Label /dev/socket/mtpd and allow access. Resolves denials such as: avc: denied { getattr } for pid=12114 comm="Binder_2" path="socket:[219779]" dev="sockfs" ino=219779 scontext=u:r:untrusted_app:s0 tcontext=u:r:system_server:s0 tclass=tcp_socket avc: denied { call } for pid=1007 comm="Binder_8" scontext=u:r:system_server:s0 tcontext=u:r:su:s0 tclass=binder avc: denied { write } for pid=1024 comm="watchdog" name="sysrq-trigger" dev="proc" ino=4026533682 scontext=u:r:system_server:s0 tcontext=u:object_r:proc:s0 tclass=file avc: denied { write } for pid=11567 comm="LegacyVpnRunner" name="mtpd" dev="tmpfs" ino=36627 scontext=u:r:system_server:s0 tcontext=u:object_r:socket_device:s0 tclass=sock_file avc: denied { ptrace } for pid=10924 comm=5369676E616C2043617463686572 scontext=u:r:system_server:s0 tcontext=u:r:system_server:s0 tclass=process avc: denied { sigkill } for pid=26077 comm="NativeCrashRepo" scontext=u:r:system_server:s0 tcontext=u:r:zygote:s0 tclass=process avc: denied { write } for pid=1024 comm="android.bg" scontext=u:r:system_server:s0 tcontext=u:r:system_server:s0 tclass=netlink_socket avc: denied { getattr } for pid=473 comm="FinalizerDaemon" path="socket:[11467]" dev="sockfs" ino=11467 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=tcp_socket avc: denied { getattr } for pid=473 comm="FinalizerDaemon" path="socket:[12076]" dev="sockfs" ino=12076 scontext=u:r:system_server:s0 tcontext=u:r:mediaserv er:s0 tclass=udp_socket avc: denied { getopt } for pid=473 comm="FinalizerDaemon" laddr=192.168.159.172 lport=51576 faddr=93.127.173.40 fport=554 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=tcp_socket avc: denied { getopt } for pid=473 comm="FinalizerDaemon" lport=15658 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=udp_socket avc: denied { read write } for pid=21384 comm="rtsp" path="socket:[443742]" dev="sockfs" ino=443742 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s 0 tclass=tcp_socket avc: denied { read write } for pid=21384 comm="rtsp" path="socket:[444842]" dev="sockfs" ino=444842 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=udp_socket avc: denied { setopt } for pid=1326 comm="Binder_9" lport=16216 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=udp_socket avc: denied { setopt } for pid=1676 comm="Binder_6" laddr=192.168.156.130 lport=51044 faddr=74.125.214.81 fport=554 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=tcp_socket avc: denied { getattr } for pid=10915 comm="system_server" path="/dev/mdm" dev="tmpfs" ino=7484 scontext=u:r:system_server:s0 tcontext=u:object_r:radio_device:s0 tclass=chr_file avc: denied { read } for pid=10915 comm="system_server" name="mdm" dev="tmpfs" ino=7484 scontext=u:r:system_server:s0 tcontext=u:object_r:radio_device:s0 tclass=chr_file avc: denied { unlink } for pid=14866 comm="system_server" name="wallpaper" dev="mmcblk0p9" ino=285715 scontext=u:r:system_server:s0 tcontext=u:object_r:wallpaper_file:s0 tclass=file avc: denied { getattr } for pid=12114 comm="Binder_2" path="socket:[219779]" dev="sockfs" ino=219779 scontext=u:r:untrusted_app:s0 tcontext=u:r:system_server:s0 tclass=tcp_socket avc: denied { getopt } for pid=32300 comm="Binder_1" laddr=::ffff:127.0.0.1 lport=4939 faddr=::ffff:127.0.0.1 fport=53318 scontext=u:r:untrusted_app:s0 tcontext=u:r:system_server:s0 tclass=tcp_socket avc: denied { read write } for pid=10840 comm="pool-17-thread-" path="socket:[205990]" dev="sockfs" ino=205990 scontext=u:r:untrusted_app:s0 tcontext=u:r:system_server:s0 tclass=tcp_socket avc: denied { write } for pid=20817 comm="dumpsys" path="/mnt/shell/emulated/0/aupt-output/bugreport-2014-02-22-11-17-16.txt.tmp" dev="fuse" ino=3100784040 scontext=u:r:system_server:s0 tcontext=u:object_r:sdcard_internal:s0 tclass=file Change-Id: I481ac26667b487031a5d3317b0a028a027a8e641 Signed-off-by: Stephen Smalley --- app.te | 5 +++-- domain.te | 2 ++ file.te | 2 ++ file_contexts | 1 + genfs_contexts | 1 + system_server.te | 34 ++++++++++++++++++++++++++++------ 6 files changed, 37 insertions(+), 8 deletions(-) diff --git a/app.te b/app.te index 8109ddb71..9adb86a80 100644 --- a/app.te +++ b/app.te @@ -33,9 +33,10 @@ allow appdomain adbd:process sigchld; # child shell or gdbserver pty access for runas. allow appdomain devpts:chr_file { getattr read write ioctl }; -# Communicate with system_server. +# Use pipes and sockets provided by system_server via binder or local socket. allow appdomain system_server:fifo_file rw_file_perms; -allow appdomain system_server:unix_stream_socket { read write setopt }; +allow appdomain system_server:unix_stream_socket { read write setopt getattr getopt shutdown }; +allow appdomain system_server:tcp_socket { read write getattr getopt shutdown }; # Communication with other apps via fifos allow appdomain appdomain:fifo_file rw_file_perms; diff --git a/domain.te b/domain.te index 013126baa..34af567d9 100644 --- a/domain.te +++ b/domain.te @@ -35,6 +35,8 @@ userdebug_or_eng(` allow domain su:fd use; allow domain su:unix_stream_socket { getattr getopt read write shutdown }; + binder_call(domain, su) + # Running something like "pm dump com.android.bluetooth" requires # fifo writes allow domain su:fifo_file { write getattr }; diff --git a/file.te b/file.te index baa77d0b7..f1bcafdbd 100644 --- a/file.te +++ b/file.te @@ -11,6 +11,7 @@ type usermodehelper, fs_type, sysfs_type; type qtaguid_proc, fs_type, mlstrustedobject; type proc_bluetooth_writable, fs_type; type proc_net, fs_type; +type proc_sysrq, fs_type; type selinuxfs, fs_type; type cgroup, fs_type, mlstrustedobject; type sysfs, fs_type, mlstrustedobject; @@ -116,6 +117,7 @@ type logdr_socket, file_type; type logdw_socket, file_type; type mdns_socket, file_type; type mdnsd_socket, file_type; +type mtpd_socket, file_type; type netd_socket, file_type; type property_socket, file_type; type racoon_socket, file_type; diff --git a/file_contexts b/file_contexts index 6b7e45c0d..8bc312f2e 100644 --- a/file_contexts +++ b/file_contexts @@ -85,6 +85,7 @@ /dev/socket/logdw u:object_r:logdw_socket:s0 /dev/socket/mdns u:object_r:mdns_socket:s0 /dev/socket/mdnsd u:object_r:mdnsd_socket:s0 +/dev/socket/mtpd u:object_r:mtpd_socket:s0 /dev/socket/netd u:object_r:netd_socket:s0 /dev/socket/property_service u:object_r:property_socket:s0 /dev/socket/racoon u:object_r:racoon_socket:s0 diff --git a/genfs_contexts b/genfs_contexts index 634f4bd6c..f247cec0c 100644 --- a/genfs_contexts +++ b/genfs_contexts @@ -4,6 +4,7 @@ genfscon rootfs / u:object_r:rootfs:s0 genfscon proc / u:object_r:proc:s0 genfscon proc /net u:object_r:proc_net:s0 genfscon proc /net/xt_qtaguid/ctrl u:object_r:qtaguid_proc:s0 +genfscon proc /sysrq-trigger u:object_r:proc_sysrq:s0 genfscon proc /sys/fs/protected_hardlinks u:object_r:proc_security:s0 genfscon proc /sys/fs/protected_symlinks u:object_r:proc_security:s0 genfscon proc /sys/fs/suid_dumpable u:object_r:proc_security:s0 diff --git a/system_server.te b/system_server.te index cf4b15843..1f6bbee38 100644 --- a/system_server.te +++ b/system_server.te @@ -16,11 +16,20 @@ allow system_server system_server_tmpfs:file execute; # For art. allow system_server dalvikcache_data_file:file execute; +# ptrace to processes in the same domain for debugging crashes. +allow system_server self:process ptrace; + # Child of the zygote. allow system_server zygote:fd use; allow system_server zygote:process sigchld; allow system_server zygote_tmpfs:file read; +# May kill zygote on crashes. +allow system_server zygote:process sigkill; + +# Read /system/bin/app_process. +allow system_server zygote_exec:file r_file_perms; + # Needed to close the zygote socket, which involves getopt / getattr allow system_server zygote:unix_stream_socket { getopt getattr }; @@ -55,6 +64,9 @@ allow system_server kernel:system module_request; # Use netlink uevent sockets. allow system_server self:netlink_kobject_uevent_socket create_socket_perms; +# Use generic netlink sockets. +allow system_server self:netlink_socket create_socket_perms; + # Kill apps. allow system_server appdomain:process { sigkill signal }; @@ -70,6 +82,9 @@ allow system_server appdomain:{ file lnk_file } rw_file_perms; allow system_server qtaguid_proc:file rw_file_perms; allow system_server qtaguid_device:chr_file rw_file_perms; +# Write to /proc/sysrq-trigger. +allow system_server proc_sysrq:file rw_file_perms; + # Read /sys/kernel/debug/wakeup_sources. allow system_server debugfs:file r_file_perms; @@ -86,6 +101,7 @@ allow system_server init:process sigchld; unix_socket_connect(system_server, property, init) unix_socket_connect(system_server, installd, installd) unix_socket_connect(system_server, lmkd, lmkd) +unix_socket_connect(system_server, mtpd, mtp) unix_socket_connect(system_server, netd, netd) unix_socket_connect(system_server, vold, vold) unix_socket_connect(system_server, zygote, zygote) @@ -109,6 +125,10 @@ r_dir_file(system_server, mediaserver) allow system_server appdomain:process getattr; allow system_server mediaserver:process getattr; +# Use sockets received over binder from various services. +allow system_server mediaserver:tcp_socket rw_socket_perms; +allow system_server mediaserver:udp_socket rw_socket_perms; + # Check SELinux permissions. selinux_check_access(system_server) @@ -126,6 +146,7 @@ allow system_server graphics_device:chr_file rw_file_perms; allow system_server iio_device:chr_file rw_file_perms; allow system_server input_device:dir r_dir_perms; allow system_server input_device:chr_file rw_file_perms; +allow system_server radio_device:chr_file r_file_perms; allow system_server tty_device:chr_file rw_file_perms; allow system_server urandom_device:chr_file rw_file_perms; allow system_server usbaccessory_device:chr_file rw_file_perms; @@ -151,7 +172,7 @@ allow system_server { apk_data_file apk_private_data_file }:file { relabelfrom r # Relabel wallpaper. allow system_server system_data_file:file relabelfrom; allow system_server wallpaper_file:file relabelto; -allow system_server wallpaper_file:file rw_file_perms; +allow system_server wallpaper_file:file { rw_file_perms unlink }; # Relabel /data/anr. allow system_server system_data_file:dir relabelfrom; @@ -199,15 +220,13 @@ allow system_server domain:file r_file_perms; allow system_server gps_device:chr_file rw_file_perms; allow system_server gps_control:file rw_file_perms; -# Allow system_server to use app-created sockets. -allow system_server appdomain:{ tcp_socket udp_socket } { setopt read write }; +# Allow system_server to use app-created sockets and pipes. +allow system_server appdomain:{ tcp_socket udp_socket } { getattr getopt setopt read write shutdown }; +allow system_server appdomain:fifo_file { getattr read write }; # Allow abstract socket connection allow system_server rild:unix_stream_socket connectto; -# connect to vpn tunnel -allow system_server mtp:unix_stream_socket { connectto }; - # BackupManagerService lets PMS create a data backup file allow system_server cache_backup_file:file create_file_perms; # Relabel /data/backup @@ -217,6 +236,9 @@ allow system_server cache_backup_file:file { relabelto relabelfrom }; # LocalTransport creates and relabels /cache/backup allow system_server cache_backup_file:dir { relabelto relabelfrom create_dir_perms }; +# Access SDcard files passed via binder or sockets. +allow system_server sdcard_type:file { read write getattr }; + # Allow system to talk to usb device allow system_server usb_device:chr_file rw_file_perms; allow system_server usb_device:dir r_dir_perms;