commit b8d9b60ecb7c03d9469be89c0121263e550661ca
author Marco Nelissen <marcone@google.com> Mon Dec 19 14:06:30 2016 -0800
committer JP Sugarbroad <jpsugar@google.com> Thu Oct 19 13:01:38 2017 -0700
tree bcacb64018f9bf2dccc75496012d711e1424af55
parent 78a04ade0f6b624dd5ed0a418ce7b4d2545052f1

Fix issues with extractor dumpsys

Tracks and descriptions were added to their respective lists in
opposite order, so dumpsys could mix up the format and active
state for a given track. Also fix potential NULL pointer dereference.

Bug: 33179012
Bug: 23270724
Change-Id: I700d535da0e72f5641bf9257a34fdb5d5d068b12
(cherry picked from commit 50a6f88bc3cea96152ccf56e85a743be14aa39b0)

media/libmedia/IMediaExtractor.cpp

diff --git a/media/libmedia/IMediaExtractor.cpp b/media/libmedia/IMediaExtractor.cpp
index 72d1d7c..4be1118 100644
--- a/media/libmedia/IMediaExtractor.cpp
+++ b/media/libmedia/IMediaExtractor.cpp
@@ -209,11 +209,16 @@
     for (size_t i = 0; i < tracks.size(); i++) {
         const String8 desc = trackDescriptions.itemAt(i);
         str.appendFormat("    track {%s} ", desc.string());
-        const sp<IMediaSource> source = tracks.itemAt(i).promote();
-        if (source == NULL) {
-            str.append(": deleted\n");
+        wp<IMediaSource> wSource = tracks.itemAt(i);
+        if (wSource == NULL) {
+            str.append(": null\n");
         } else {
-            str.appendFormat(": active\n");
+            const sp<IMediaSource> source = wSource.promote();
+            if (source == NULL) {
+                str.append(": deleted\n");
+            } else {
+                str.appendFormat(": active\n");
+            }
         }
     }
     return str;
@@ -232,9 +237,14 @@
         if (extractor != NULL && extractor == ex) {
             if (instance.tracks.size() > 5) {
                 instance.tracks.resize(5);
+                instance.trackDescriptions.resize(5);
             }
             instance.tracks.push_front(source);
-            instance.trackDescriptions.add(source->getFormat()->toString());
+            if (source != NULL) {
+                instance.trackDescriptions.push_front(source->getFormat()->toString());
+            } else {
+                instance.trackDescriptions.push_front(String8::empty());
+            }
             break;
         }
     }