diff --git a/src/main/scala/com/github/shadowsocks/Shadowsocks.scala b/src/main/scala/com/github/shadowsocks/Shadowsocks.scala
index 5fa3eeec..fb51012a 100644
--- a/src/main/scala/com/github/shadowsocks/Shadowsocks.scala
+++ b/src/main/scala/com/github/shadowsocks/Shadowsocks.scala
@@ -327,8 +327,6 @@ class Shadowsocks
     ab.append("kill -9 `cat /data/data/com.github.shadowsocks/ss-local.pid`")
     ab.append("kill -9 `cat /data/data/com.github.shadowsocks/ss-tunnel.pid`")
     ab.append("kill -9 `cat /data/data/com.github.shadowsocks/tun2socks.pid`")
-    ab.append("killall -9 pdnsd")
-    ab.append("killall -9 tun2socks")
     ab.append("rm /data/data/com.github.shadowsocks/pdnsd.conf")
     ab.append("rm /data/data/com.github.shadowsocks/pdnsd.cache")
 
@@ -336,7 +334,6 @@ class Shadowsocks
 
     ab.clear()
     ab.append("kill -9 `cat /data/data/com.github.shadowsocks/redsocks.pid`")
-    ab.append("killall -9 redsocks")
     ab.append("rm /data/data/com.github.shadowsocks/redsocks.conf")
     ab.append(Utils.getIptables + " -t nat -F OUTPUT")
 
diff --git a/src/main/scala/com/github/shadowsocks/ShadowsocksNatService.scala b/src/main/scala/com/github/shadowsocks/ShadowsocksNatService.scala
index 76172754..a799f4a8 100644
--- a/src/main/scala/com/github/shadowsocks/ShadowsocksNatService.scala
+++ b/src/main/scala/com/github/shadowsocks/ShadowsocksNatService.scala
@@ -151,7 +151,7 @@ class ShadowsocksNatService extends Service with BaseService {
     }
 
     val cmd = if (Build.VERSION.SDK_INT >= 20) {
-      "system/bin/" + args
+      "/system/bin/" + args
     } else {
       Path.BASE + args
     }
@@ -185,7 +185,7 @@ class ShadowsocksNatService extends Service with BaseService {
       p.println(conf)
     })
     val cmd = if (Build.VERSION.SDK_INT >= 20) {
-      "system/bin/" + args
+      "/system/bin/" + args
     } else {
       Path.BASE + args
     }
@@ -315,16 +315,14 @@ class ShadowsocksNatService extends Service with BaseService {
     val ab = new ArrayBuffer[String]
 
     ab.append("kill -9 `cat " + Path.BASE + "ss-tunnel.pid`")
-
     ab.append("kill -9 `cat " + Path.BASE +"redsocks.pid`")
     ab.append("killall -9 redsocks")
-
     ab.append("kill -15 `cat " + Path.BASE + "pdnsd.pid`")
     ab.append("killall -15 pdnsd")
 
     Console.runRootCommand(ab.toArray)
-    ab.clear()
 
+    ab.clear()
     ab.append("kill -9 `cat " + Path.BASE + "ss-local.pid`")
 
     Console.runCommand(ab.toArray)