initial lmkd policy.

* Allow writes to /proc/PID/oom_score_adj
* Allow writes to /sys/module/lowmemorykiller/*

Addresses the following denials:
<5>[    3.825371] type=1400 audit(9781555.430:5): avc:  denied  { write } for  pid=176 comm="lmkd" name="minfree" dev="sysfs" ino=6056 scontext=u:r:lmkd:s0 tcontext=u:object_r:sysfs:s0 tclass=file
<5>[   48.874747] type=1400 audit(9781600.639:16): avc:  denied  { search } for  pid=176 comm="lmkd" name="896" dev="proc" ino=9589 scontext=u:r:lmkd:s0 tcontext=u:r:system_server:s0 tclass=dir
<5>[   48.874889] type=1400 audit(9781600.639:17): avc:  denied  { dac_override } for  pid=176 comm="lmkd" capability=1  scontext=u:r:lmkd:s0 tcontext=u:r:lmkd:s0 tclass=capability
<5>[   48.874982] type=1400 audit(9781600.639:18): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=8942 scontext=u:r:lmkd:s0 tcontext=u:r:system_server:s0 tclass=file
<5>[   48.875075] type=1400 audit(9781600.639:19): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=8942 scontext=u:r:lmkd:s0 tcontext=u:r:system_server:s0 tclass=file
<5>[   49.409231] type=1400 audit(9781601.169:20): avc:  denied  { write } for  pid=176 comm="lmkd" name="minfree" dev="sysfs" ino=6056 scontext=u:r:lmkd:s0 tcontext=u:object_r:sysfs:s0 tclass=file
<5>[  209.081990] type=1400 audit(9781760.839:24): avc:  denied  { search } for  pid=176 comm="lmkd" name="1556" dev="proc" ino=10961 scontext=u:r:lmkd:s0 tcontext=u:r:platform_app:s0 tclass=dir
<5>[  209.082240] type=1400 audit(9781760.839:25): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11654 scontext=u:r:lmkd:s0 tcontext=u:r:platform_app:s0 tclass=file
<5>[  209.082498] type=1400 audit(9781760.839:26): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11654 scontext=u:r:lmkd:s0 tcontext=u:r:platform_app:s0 tclass=file
<5>[  209.119673] type=1400 audit(9781760.879:27): avc:  denied  { search } for  pid=176 comm="lmkd" name="1577" dev="proc" ino=12708 scontext=u:r:lmkd:s0 tcontext=u:r:release_app:s0 tclass=dir
<5>[  209.119937] type=1400 audit(9781760.879:28): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11657 scontext=u:r:lmkd:s0 tcontext=u:r:release_app:s0 tclass=file
<5>[  209.120105] type=1400 audit(9781760.879:29): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11657 scontext=u:r:lmkd:s0 tcontext=u:r:release_app:s0 tclass=file
<5>[  209.235597] type=1400 audit(9781760.999:30): avc:  denied  { search } for  pid=176 comm="lmkd" name="1600" dev="proc" ino=11659 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=dir
<5>[  209.235798] type=1400 audit(9781760.999:31): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11667 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=file
<5>[  209.236006] type=1400 audit(9781760.999:32): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11667 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=file
<5>[  214.297283] type=1400 audit(9781766.059:64): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11211 scontext=u:r:lmkd:s0 tcontext=u:r:untrusted_app:s0 tclass=file
<5>[  214.297415] type=1400 audit(9781766.059:65): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11211 scontext=u:r:lmkd:s0 tcontext=u:r:untrusted_app:s0 tclass=file
<5>[  214.355060] type=1400 audit(9781766.119:66): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12907 scontext=u:r:lmkd:s0 tcontext=u:r:system_app:s0 tclass=file
<5>[  214.355236] type=1400 audit(9781766.119:67): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12907 scontext=u:r:lmkd:s0 tcontext=u:r:system_app:s0 tclass=file
<5>[  214.516920] type=1400 audit(9781766.279:68): avc:  denied  { search } for  pid=176 comm="lmkd" name="1907" dev="proc" ino=11742 scontext=u:r:lmkd:s0 tcontext=u:r:media_app:s0 tclass=dir
<5>[  214.678861] type=1400 audit(9781766.439:69): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12915 scontext=u:r:lmkd:s0 tcontext=u:r:media_app:s0 tclass=file
<5>[  214.678992] type=1400 audit(9781766.439:70): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12915 scontext=u:r:lmkd:s0 tcontext=u:r:media_app:s0 tclass=file
<5>[  214.708284] type=1400 audit(9781766.469:71): avc:  denied  { search } for  pid=176 comm="lmkd" name="1765" dev="proc" ino=12851 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=dir
<5>[  214.708435] type=1400 audit(9781766.469:72): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12870 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=file
<5>[  214.708648] type=1400 audit(9781766.469:73): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12870 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=file

Change-Id: Ie3c1ab8ce9e77742d0cc3c73f40010afd018ccd4
diff --git a/system_server.te b/system_server.te
index 27dc52d..945b59b 100644
--- a/system_server.te
+++ b/system_server.te
@@ -251,3 +251,8 @@
 # logd access, system_server inherit logd write socket
 # (urge is to deprecate this long term)
 allow system_server zygote:unix_dgram_socket write;
+
+# Be consistent with DAC permissions. Allow system_server to write to
+# /sys/module/lowmemorykiller/parameters/adj
+# /sys/module/lowmemorykiller/parameters/minfree
+allow system_server sysfs_lowmemorykiller:file w_file_perms;