Use SIGKILL to kill old processes

Fix shadowsocks#1455. Note that in later Android versions, only processes under same uid will be listed and this will be quite efficient.
sdwwld · Nov 18, 2017 · dc2a5ca · dc2a5ca
1 parent ae171a7
commit dc2a5ca
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Showing 3 changed files with 32 additions and 68 deletions.
diff --git a/mobile/src/main/java/com/github/shadowsocks/JniHelper.java b/mobile/src/main/java/com/github/shadowsocks/JniHelper.java
@@ -64,6 +64,7 @@ public static boolean waitForCompat(Process process, long millis) throws Excepti
         }
     }
 
+    public static native int sigkill(int pid);
     private static native int sigterm(Process process);
     private static native Integer getExitValue(Process process);
     private static native Object getExitValueMutex(Process process);

diff --git a/mobile/src/main/jni/jni-helper.cpp b/mobile/src/main/jni/jni-helper.cpp
@@ -31,7 +31,13 @@ static int sdk_version() {
     return atoi(version);
 }
 
-jint Java_com_github_shadowsocks_jnihelper_sigterm(JNIEnv *env, jobject thiz, jobject process) {
+extern "C" {
+JNIEXPORT jint JNICALL Java_com_github_shadowsocks_JniHelper_sigkill(JNIEnv *env, jobject thiz, jint pid) {
+    // Suppress "No such process" errors. We just want the process killed. It's fine if it's already killed.
+    return kill(pid, SIGKILL) == -1 && errno != ESRCH ? errno : 0;
+}
+
+JNIEXPORT jint JNICALL Java_com_github_shadowsocks_JniHelper_sigterm(JNIEnv *env, jobject thiz, jobject process) {
     if (!env->IsInstanceOf(process, ProcessImpl)) {
         THROW(env, "java/lang/ClassCastException",
                    "Unsupported process object. Only java.lang.ProcessManager$ProcessImpl is accepted.");
@@ -42,7 +48,8 @@ jint Java_com_github_shadowsocks_jnihelper_sigterm(JNIEnv *env, jobject thiz, jo
     return kill(pid, SIGTERM) == -1 && errno != ESRCH ? errno : 0;
 }
 
-jobject Java_com_github_shadowsocks_jnihelper_getExitValue(JNIEnv *env, jobject thiz, jobject process) {
+JNIEXPORT jobject JNICALL
+        Java_com_github_shadowsocks_JniHelper_getExitValue(JNIEnv *env, jobject thiz, jobject process) {
     if (!env->IsInstanceOf(process, ProcessImpl)) {
         THROW(env, "java/lang/ClassCastException",
                    "Unsupported process object. Only java.lang.ProcessManager$ProcessImpl is accepted.");
@@ -51,7 +58,8 @@ jobject Java_com_github_shadowsocks_jnihelper_getExitValue(JNIEnv *env, jobject
     return env->GetObjectField(process, ProcessImpl_exitValue);
 }
 
-jobject Java_com_github_shadowsocks_jnihelper_getExitValueMutex(JNIEnv *env, jobject thiz, jobject process) {
+JNIEXPORT jobject JNICALL
+        Java_com_github_shadowsocks_JniHelper_getExitValueMutex(JNIEnv *env, jobject thiz, jobject process) {
     if (!env->IsInstanceOf(process, ProcessImpl)) {
         THROW(env, "java/lang/ClassCastException",
                    "Unsupported process object. Only java.lang.ProcessManager$ProcessImpl is accepted.");
@@ -60,11 +68,12 @@ jobject Java_com_github_shadowsocks_jnihelper_getExitValueMutex(JNIEnv *env, job
     return env->GetObjectField(process, ProcessImpl_exitValueMutex);
 }
 
-void Java_com_github_shadowsocks_jnihelper_close(JNIEnv *env, jobject thiz, jint fd) {
+JNIEXPORT void JNICALL Java_com_github_shadowsocks_JniHelper_close(JNIEnv *env, jobject thiz, jint fd) {
     close(fd);
 }
 
-jint Java_com_github_shadowsocks_jnihelper_sendfd(JNIEnv *env, jobject thiz, jint tun_fd, jstring path) {
+JNIEXPORT jint JNICALL
+        Java_com_github_shadowsocks_JniHelper_sendFd(JNIEnv *env, jobject thiz, jint tun_fd, jstring path) {
     int fd;
     struct sockaddr_un addr;
     const char *sock_str  = env->GetStringUTFChars(path, 0);
@@ -94,56 +103,6 @@ jint Java_com_github_shadowsocks_jnihelper_sendfd(JNIEnv *env, jobject thiz, jin
     env->ReleaseStringUTFChars(path, sock_str);
     return 0;
 }
-
-static const char *classPathName = "com/github/shadowsocks/JniHelper";
-
-static JNINativeMethod method_table[] = {
-    { "close", "(I)V",
-        (void*) Java_com_github_shadowsocks_jnihelper_close },
-    { "sendFd", "(ILjava/lang/String;)I",
-        (void*) Java_com_github_shadowsocks_jnihelper_sendfd },
-    { "sigterm", "(Ljava/lang/Process;)I",
-        (void*) Java_com_github_shadowsocks_jnihelper_sigterm },
-    { "getExitValue", "(Ljava/lang/Process;)Ljava/lang/Integer;",
-        (void*) Java_com_github_shadowsocks_jnihelper_getExitValue },
-    { "getExitValueMutex", "(Ljava/lang/Process;)Ljava/lang/Object;",
-        (void*) Java_com_github_shadowsocks_jnihelper_getExitValueMutex }
-};
-
-/*
- * Register several native methods for one class.
- */
-static int registerNativeMethods(JNIEnv* env, const char* className,
-    JNINativeMethod* gMethods, int numMethods)
-{
-    jclass clazz;
-
-    clazz = env->FindClass(className);
-    if (clazz == NULL) {
-        LOGE("Native registration unable to find class '%s'", className);
-        return JNI_FALSE;
-    }
-    if (env->RegisterNatives(clazz, gMethods, numMethods) < 0) {
-        LOGE("RegisterNatives failed for '%s'", className);
-        return JNI_FALSE;
-    }
-
-    return JNI_TRUE;
-}
-
-/*
- * Register native methods for all classes we know about.
- *
- * returns JNI_TRUE on success.
- */
-static int registerNatives(JNIEnv* env)
-{
-  if (!registerNativeMethods(env, classPathName, method_table,
-                 sizeof(method_table) / sizeof(method_table[0]))) {
-    return JNI_FALSE;
-  }
-
-  return JNI_TRUE;
 }
 
 /*
@@ -167,11 +126,6 @@ jint JNI_OnLoad(JavaVM* vm, void* reserved) {
     }
     env = uenv.env;
 
-    if (registerNatives(env) != JNI_TRUE) {
-        THROW(env, "java/lang/RuntimeException", "registerNativeMethods failed");
-        goto bail;
-    }
-
     if (sdk_version() < 24) {
         if (!(ProcessImpl = env->FindClass("java/lang/ProcessManager$ProcessImpl"))) {
             THROW(env, "java/lang/RuntimeException", "ProcessManager$ProcessImpl not found");

diff --git a/mobile/src/main/scala/com/github/shadowsocks/bg/Executable.scala b/mobile/src/main/scala/com/github/shadowsocks/bg/Executable.scala
@@ -1,9 +1,14 @@
 package com.github.shadowsocks.bg
 
+import java.io.File
 import java.util.Locale
-import java.util.concurrent.TimeUnit
 
+import android.text.TextUtils
 import android.util.Log
+import com.github.shadowsocks.JniHelper
+import com.github.shadowsocks.ShadowsocksApplication.app
+
+import scala.io.Source
 
 /**
   * @author Mygod
@@ -16,12 +21,16 @@ object Executable {
   val TUN2SOCKS = "libtun2socks.so"
   val OVERTURE = "liboverture.so"
 
-  val EXECUTABLES = Array(SS_LOCAL, SS_TUNNEL, PDNSD, REDSOCKS, TUN2SOCKS, OVERTURE)
+  val EXECUTABLES = Set(SS_LOCAL, SS_TUNNEL, PDNSD, REDSOCKS, TUN2SOCKS, OVERTURE)
 
-  def killAll() {
-    val killer = new ProcessBuilder("killall" +: EXECUTABLES: _*).start()
-    if (!killer.waitFor(1, TimeUnit.SECONDS))
-      Log.w("killall", "%s didn't exit within 1s. Post-crash clean-up may have failed."
-        .formatLocal(Locale.ENGLISH, killer.toString))
-  }
+  def killAll(): Unit =
+    for (process <- new File("/proc").listFiles((_, name) => TextUtils.isDigitsOnly(name))) {
+      val exe = new File(Source.fromFile(new File(process, "cmdline")).mkString.split("\0", 2).head)
+      if (exe.getParent == app.getApplicationInfo.nativeLibraryDir && EXECUTABLES.contains(exe.getName))
+        JniHelper.sigkill(process.getName.toInt) match {
+          case 0 =>
+          case errno => Log.w("kill", "SIGKILL %s (%d) failed with %d"
+            .formatLocal(Locale.ENGLISH, exe.getAbsolutePath, process.getName, errno))
+        }
+    }
 }