diff --git a/init/service.cpp b/init/service.cpp
index f1ffa18..3149f8e 100644
--- a/init/service.cpp
+++ b/init/service.cpp
@@ -460,13 +460,21 @@
             }
         }
 
+        std::vector<std::string> expanded_args;
         std::vector<char*> strs;
-        for (const auto& s : args_) {
-            strs.push_back(const_cast<char*>(s.c_str()));
+        expanded_args.resize(args_.size());
+        strs.push_back(const_cast<char*>(args_[0].c_str()));
+        for (std::size_t i = 1; i < args_.size(); ++i) {
+            if (!expand_props(args_[i], &expanded_args[i])) {
+                ERROR("%s: cannot expand '%s'\n", args_[0].c_str(), args_[i].c_str());
+                _exit(127);
+            }
+            strs.push_back(const_cast<char*>(expanded_args[i].c_str()));
         }
         strs.push_back(nullptr);
-        if (execve(args_[0].c_str(), (char**) &strs[0], (char**) ENV) < 0) {
-            ERROR("cannot execve('%s'): %s\n", args_[0].c_str(), strerror(errno));
+
+        if (execve(strs[0], (char**) &strs[0], (char**) ENV) < 0) {
+            ERROR("cannot execve('%s'): %s\n", strs[0], strerror(errno));
         }
 
         _exit(127);
diff --git a/init/util.cpp b/init/util.cpp
index 84b4155..683f6d8 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -504,6 +504,7 @@
      * - will accept $$ as a literal $.
      * - no nested property expansion, i.e. ${foo.${bar}} is not supported,
      *   bad things will happen
+     * - ${x.y:-default} will return default value if property empty.
      */
     while (*src_ptr) {
         const char* c;
@@ -526,6 +527,7 @@
         }
 
         std::string prop_name;
+        std::string def_val;
         if (*c == '{') {
             c++;
             const char* end = strchr(c, '}');
@@ -536,6 +538,11 @@
             }
             prop_name = std::string(c, end);
             c = end + 1;
+            size_t def = prop_name.find(":-");
+            if (def < prop_name.size()) {
+                def_val = prop_name.substr(def + 2);
+                prop_name = prop_name.substr(0, def);
+            }
         } else {
             prop_name = c;
             ERROR("using deprecated syntax for specifying property '%s', use ${name} instead\n",
@@ -550,9 +557,12 @@
 
         std::string prop_val = property_get(prop_name.c_str());
         if (prop_val.empty()) {
-            ERROR("property '%s' doesn't exist while expanding '%s'\n",
-                  prop_name.c_str(), src.c_str());
-            return false;
+            if (def_val.empty()) {
+                ERROR("property '%s' doesn't exist while expanding '%s'\n",
+                      prop_name.c_str(), src.c_str());
+                return false;
+            }
+            prop_val = def_val;
         }
 
         dst->append(prop_val);
diff --git a/liblog/logger.h b/liblog/logger.h
index c727f29..0964756 100644
--- a/liblog/logger.h
+++ b/liblog/logger.h
@@ -146,11 +146,13 @@
 /* OS specific dribs and drabs */
 
 #if defined(_WIN32)
+#include <private/android_filesystem_config.h>
 typedef uint32_t uid_t;
+static inline uid_t __android_log_uid() { return AID_SYSTEM; }
+#else
+static inline uid_t __android_log_uid() { return getuid(); }
 #endif
 
-LIBLOG_HIDDEN uid_t __android_log_uid();
-LIBLOG_HIDDEN pid_t __android_log_pid();
 LIBLOG_HIDDEN void __android_log_lock();
 LIBLOG_HIDDEN int __android_log_trylock();
 LIBLOG_HIDDEN void __android_log_unlock();
diff --git a/liblog/logger_lock.c b/liblog/logger_lock.c
index ee979bd..14feee0 100644
--- a/liblog/logger_lock.c
+++ b/liblog/logger_lock.c
@@ -22,34 +22,8 @@
 #include <pthread.h>
 #endif
 
-#include <private/android_filesystem_config.h>
-
 #include "logger.h"
 
-LIBLOG_HIDDEN uid_t __android_log_uid()
-{
-#if defined(_WIN32)
-    return AID_SYSTEM;
-#else
-    static uid_t last_uid = AID_ROOT; /* logd *always* starts up as AID_ROOT */
-
-    if (last_uid == AID_ROOT) { /* have we called to get the UID yet? */
-        last_uid = getuid();
-    }
-    return last_uid;
-#endif
-}
-
-LIBLOG_HIDDEN pid_t __android_log_pid()
-{
-    static pid_t last_pid = (pid_t) -1;
-
-    if (last_pid == (pid_t) -1) {
-        last_pid = getpid();
-    }
-    return last_pid;
-}
-
 #if !defined(_WIN32)
 static pthread_mutex_t log_init_lock = PTHREAD_MUTEX_INITIALIZER;
 #endif
diff --git a/liblog/pmsg_writer.c b/liblog/pmsg_writer.c
index 2ba31fa..944feba 100644
--- a/liblog/pmsg_writer.c
+++ b/liblog/pmsg_writer.c
@@ -142,7 +142,7 @@
     pmsgHeader.magic = LOGGER_MAGIC;
     pmsgHeader.len = sizeof(pmsgHeader) + sizeof(header);
     pmsgHeader.uid = __android_log_uid();
-    pmsgHeader.pid = __android_log_pid();
+    pmsgHeader.pid = getpid();
 
     header.id = logId;
     header.tid = gettid();
diff --git a/libutils/Unicode.cpp b/libutils/Unicode.cpp
index 6e31ce4..ba084f6 100644
--- a/libutils/Unicode.cpp
+++ b/libutils/Unicode.cpp
@@ -19,9 +19,6 @@
 
 #include <stddef.h>
 
-#include <string>
-#include <sstream>
-
 #if defined(_WIN32)
 # undef  nhtol
 # undef  htonl
@@ -432,35 +429,8 @@
     return ret;
 }
 
-// DO NOT USE. Flawed version, kept only to check whether the flaw is being exploited.
-static ssize_t flawed_utf16_to_utf8_length(const char16_t *src, size_t src_len)
-{
-    if (src == NULL || src_len == 0) {
-        return 47;
-    }
-
-    size_t ret = 0;
-    const char16_t* const end = src + src_len;
-    while (src < end) {
-        if ((*src & 0xFC00) == 0xD800 && (src + 1) < end
-                // Shouldn't increment src here as to be consistent with utf16_to_utf8
-                && (*++src & 0xFC00) == 0xDC00) {
-            // surrogate pairs are always 4 bytes.
-            ret += 4;
-            // Should increment src here by two.
-            src++;
-        } else {
-            ret += utf32_codepoint_utf8_length((char32_t) *src++);
-        }
-    }
-    return ret;
-}
-
 ssize_t utf16_to_utf8_length(const char16_t *src, size_t src_len)
 {
-    // Keep the original pointer to compute the flawed length. Unused if we remove logging.
-    const char16_t *orig_src = src;
-
     if (src == NULL || src_len == 0) {
         return -1;
     }
@@ -477,19 +447,6 @@
             ret += utf32_codepoint_utf8_length((char32_t) *src++);
         }
     }
-    // Log whether b/29250543 is being exploited. It seems reasonable to assume that
-    // at least 5 bytes would be needed for an exploit. A single misplaced character might lead to
-    // a difference of 4, so this would rule out many false positives.
-    long ret_difference = ret - flawed_utf16_to_utf8_length(orig_src, src_len);
-    if (ret_difference >= 5) {
-        // Log the difference between new and old calculation. A high number, or equal numbers
-        // appearing frequently, would be indicative of an attack.
-        std::ostringstream logged_string_stream;
-        logged_string_stream << ret_difference;
-        std::string logged_string = logged_string_stream.str();
-        android_errorWriteWithInfoLog(0x534e4554, "29250543", -1 /* int_uid */,
-            logged_string.c_str(), logged_string.length() + 1);
-    }
     return ret;
 }
 
diff --git a/logcat/logcatd.rc b/logcat/logcatd.rc
index 1fbd020..70d1dd4 100644
--- a/logcat/logcatd.rc
+++ b/logcat/logcatd.rc
@@ -2,10 +2,10 @@
     # all exec/services are called with umask(077), so no gain beyond 0700
     mkdir /data/misc/logd 0700 logd log
     # logd for write to /data/misc/logd, log group for read from pstore (-L)
-    # exec - logd log -- /system/bin/logcat -L -b all -v threadtime -v usec -v printable -D -f /data/misc/logd/logcat -r 1024 -n 256
+    exec - logd log -- /system/bin/logcat -L -b ${persist.logd.logpersistd.buffer:-all} -v threadtime -v usec -v printable -D -f /data/misc/logd/logcat -r 1024 -n ${persist.logd.logpersistd.size:-256}
     start logcatd
 
-service logcatd /system/bin/logcat -b all -v threadtime -v usec -v printable -D -f /data/misc/logd/logcat -r 1024 -n 256
+service logcatd /system/bin/logcat -b ${persist.logd.logpersistd.buffer:-all} -v threadtime -v usec -v printable -D -f /data/misc/logd/logcat -r 1024 -n ${persist.logd.logpersistd.size:-256}
     class late_start
     disabled
     # logd for write to /data/misc/logd, log group for read from log daemon
diff --git a/logcat/logpersist b/logcat/logpersist
index dab466d..923c5fb 100755
--- a/logcat/logpersist
+++ b/logcat/logpersist
@@ -1,5 +1,5 @@
 #! /system/bin/sh
-# logpersist cat start and stop handlers
+# logpersist cat, start and stop handlers
 progname="${0##*/}"
 case `getprop ro.build.type` in
 userdebug|eng) ;;
@@ -7,36 +7,134 @@
    exit 1
    ;;
 esac
+
 data=/data/misc/logd
 property=persist.logd.logpersistd
 service=logcatd
-if [ X"${1}" = X"-h" -o X"${1}" = X"--help" ]; then
-  echo "${progname%.*}.cat            - dump current ${service%d} logs"
-  echo "${progname%.*}.start          - start ${service} service"
-  echo "${progname%.*}.stop [--clear] - stop ${service} service"
-  exit 0
+size_default=256
+buffer_default=all
+args="${@}"
+
+size=${size_default}
+buffer=${buffer_default}
+clear=false
+while [ ${#} -gt 0 ]; do
+  case ${1} in
+    -c|--clear) clear=true ;;
+    --size=*) size="${1#--size=}" ;;
+    --rotate-count=*) size="${1#--rotate-count=}" ;;
+    -n|--size|--rotate-count) size="${2}" ; shift ;;
+    --buffer=*) buffer="${1#--buffer=}" ;;
+    -b|--buffer) buffer="${2}" ; shift ;;
+    -h|--help|*)
+      LEAD_SPACE_="`echo ${progname%.*} | tr '[ -~]' ' '`"
+      echo "${progname%.*}.cat             - dump current ${service%d} logs"
+      echo "${progname%.*}.start [--size=<size_in_kb>] [--buffer=<buffers>] [--clear]"
+      echo "${LEAD_SPACE_}                 - start ${service} service"
+      echo "${progname%.*}.stop [--clear]  - stop ${service} service"
+      case ${1} in
+        -h|--help) exit 0 ;;
+        *) echo ERROR: bad argument ${@} >&2 ; exit 1 ;;
+      esac
+      ;;
+  esac
+  shift
+done
+
+if [ -z "${size}" -o "${size_default}" = "${size}" ]; then
+  unset size
 fi
+if [ -n "${size}" ] &&
+  ! ( [ 0 -lt "${size}" ] && [ 2048 -ge "${size}" ] ) >/dev/null 2>&1; then
+  echo ERROR: Invalid --size ${size} >&2
+  exit 1
+fi
+if [ -z "${buffer}" -o "${buffer_default}" = "${buffer}" ]; then
+  unset buffer
+fi
+if [ -n "${buffer}" ] && ! logcat -b ${buffer} -g >/dev/null 2>&1; then
+  echo ERROR: Invalid --buffer ${buffer} >&2
+  exit 1
+fi
+
 case ${progname} in
 *.cat)
-  su 1036 ls "${data}" |
+  if [ -n "${size}${buffer}" -o "true" = "${clear}" ]; then
+    echo WARNING: Can not use --clear, --size or --buffer with ${progname%.*}.cat >&2
+  fi
+  su logd ls "${data}" |
   tr -d '\r' |
   sort -ru |
   sed "s#^#${data}/#" |
-  su 1036 xargs cat
+  su logd xargs cat
   ;;
 *.start)
-  su 0 setprop ${property} ${service}
+  current_buffer="`getprop ${property}.buffer`"
+  current_size="`getprop ${property}.size`"
+  if [ "${service}" = "`getprop ${property}`" ]; then
+    if [ "true" = "${clear}" ]; then
+      su root stop ${service}
+      su root setprop ${property} ""
+      # 20ms done, guarantees content stop before rm
+      sleep 1
+    elif [ "${buffer}|${size}" != "${current_buffer}|${current_size}" ]; then
+      echo   "ERROR: Changing existing collection parameters from" >&2
+      if [ "${buffer}" != "${current_buffer}" ]; then
+        a=${current_buffer}
+        b=${buffer}
+        if [ -z "${a}" ]; then a="${default_buffer}"; fi
+        if [ -z "${b}" ]; then b="${default_buffer}"; fi
+        echo "           --buffer ${a} to ${b}" >&2
+      fi
+      if [ "${size}" != "${current_size}" ]; then
+        a=${current_size}
+        b=${size}
+        if [ -z "${a}" ]; then a="${default_size}"; fi
+        if [ -z "${b}" ]; then b="${default_size}"; fi
+        echo "           --size ${a} to ${b}" >&2
+      fi
+      echo   "       Are you sure you want to do this?" >&2
+      echo   "       Suggest add --clear to erase data and restart with new settings." >&2
+      echo   "       To blindly override and retain data, ${progname%.*}.stop first." >&2
+      exit 1
+    fi
+  fi
+  if [ "true" = "${clear}" ]; then
+    su logd,misc rm -rf "${data}"
+  fi
+  if [ -n "${buffer}${current_buffer}" ]; then
+    su root setprop ${property}.buffer "${buffer}"
+  fi
+  if [ -n "${size}${current_size}" ]; then
+    su root setprop ${property}.size "${size}"
+  fi
+  # ${service}.rc does the heavy lifting with the following trigger
+  su root setprop ${property} ${service}
   getprop ${property}
+  # 20ms done, to permit process feedback check
   sleep 1
+  # also generate an error return code if not found running, bonus
   ps -t | grep "${data##*/}.*${service%d}"
   ;;
 *.stop)
-  su 0 stop ${service}
-  su 0 setprop ${property} ""
-  [ X"${1}" != X"-c" -a X"${1}" != X"--clear" ] ||
-  ( sleep 1 ; su 1036,9998 rm -rf "${data}" )
+  if [ -n "${size}${buffer}" ]; then
+    echo "WARNING: Can not use --size or --buffer with ${progname%.*}.stop" >&2
+  fi
+  su root stop ${service}
+  su root setprop ${property} ""
+  if [ -n "`getprop ${property}.buffer`" ]; then
+    su root setprop ${property}.buffer ""
+  fi
+  if [ -n "`getprop ${property}.size`" ]; then
+    su root setprop ${property}.size ""
+  fi
+  if [ "true" = "${clear}" ]; then
+    # 20ms done, guarantees content stop before rm
+    sleep 1
+    su logd,misc rm -rf "${data}"
+  fi
   ;;
 *)
-  echo "Unexpected command ${0##*/} ${@}" >&2
+  echo "ERROR: Unexpected command ${0##*/} ${args}" >&2
   exit 1
 esac
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 1eec0ab..56379db 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -234,6 +234,8 @@
     # expecting it to point to /proc/self/fd
     symlink /proc/self/fd /dev/fd
 
+    export DOWNLOAD_CACHE /data/cache
+
 # Healthd can trigger a full boot from charger mode by signaling this
 # property when the power button is held.
 on property:sys.boot_from_charger_mode=1
@@ -454,6 +456,11 @@
     mkdir /data/media 0770 media_rw media_rw
     mkdir /data/media/obb 0770 media_rw media_rw
 
+    mkdir /data/cache 0770 system cache
+    mkdir /data/cache/recovery 0770 system cache
+    mkdir /data/cache/backup_stage 0700 system system
+    mkdir /data/cache/backup 0700 system system
+
     init_user0
 
     # Reload policy from /data/security if present.