From 5c0232c572a4a25d295026335bbb85852d3c0e7c Mon Sep 17 00:00:00 2001
From: Chenbo Feng <fengc@google.com>
Date: Fri, 14 Sep 2018 15:16:48 -0700
Subject: [PATCH] Don't check qtaguid file unless using them

The proc file of xt_qtaguid module is not necessarily exist on future
devices. We should only check it if the device need to read the stats
file for network usage information.

Bug: 79938294
Test: NetworkUsageStatsTest TrafficStatsTest
Change-Id: I5ac6feef8b9a26daa68b381a985925e24b0d80af
---
 .../jni/com_android_internal_net_NetworkStatsFactory.cpp | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/core/jni/com_android_internal_net_NetworkStatsFactory.cpp b/core/jni/com_android_internal_net_NetworkStatsFactory.cpp
index c15b7ee4fe..109e65c4a1 100644
--- a/core/jni/com_android_internal_net_NetworkStatsFactory.cpp
+++ b/core/jni/com_android_internal_net_NetworkStatsFactory.cpp
@@ -285,10 +285,6 @@ static int statsLinesToNetworkStats(JNIEnv* env, jclass clazz, jobject stats,
 static int readNetworkStatsDetail(JNIEnv* env, jclass clazz, jobject stats, jstring path,
                                   jint limitUid, jobjectArray limitIfacesObj, jint limitTag,
                                   jboolean useBpfStats) {
-    ScopedUtfChars path8(env, path);
-    if (path8.c_str() == NULL) {
-        return -1;
-    }
 
     std::vector<std::string> limitIfaces;
     if (limitIfacesObj != NULL && env->GetArrayLength(limitIfacesObj) > 0) {
@@ -308,6 +304,11 @@ static int readNetworkStatsDetail(JNIEnv* env, jclass clazz, jobject stats, jstr
         if (parseBpfNetworkStatsDetail(&lines, limitIfaces, limitTag, limitUid) < 0)
             return -1;
     } else {
+        ScopedUtfChars path8(env, path);
+        if (path8.c_str() == NULL) {
+            ALOGE("the qtaguid legacy path is invalid: %s", path8.c_str());
+            return -1;
+        }
         if (legacyReadNetworkStatsDetail(&lines, limitIfaces, limitTag,
                                          limitUid, path8.c_str()) < 0)
             return -1;