From e3589b2584f5638c26e0148ebe16bbe13d135d61 Mon Sep 17 00:00:00 2001
From: Josh Gao <jmgao@google.com>
Date: Fri, 28 Sep 2018 10:59:16 -0700
Subject: ParcelFileDescriptor: fix various ownership mistakes.

Return a duped file descriptor instead of one that's owned by another
object in ParcelFileDescriptor's fromSocket, fromDatagramSocket, and
fromData.

Bug: http://b/116802667
Test: treehugger
Change-Id: Ic66009678894d9d7e972c99d24d4ee9c2f09a2db
---
 core/java/android/os/ParcelFileDescriptor.java | 32 +++++++++++++++++++-------
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/core/java/android/os/ParcelFileDescriptor.java b/core/java/android/os/ParcelFileDescriptor.java
index 7409ca741c52..2c0394453097 100644
--- a/core/java/android/os/ParcelFileDescriptor.java
+++ b/core/java/android/os/ParcelFileDescriptor.java
@@ -55,6 +55,7 @@ import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InterruptedIOException;
+import java.io.UncheckedIOException;
 import java.net.DatagramSocket;
 import java.net.Socket;
 import java.nio.ByteOrder;
@@ -397,26 +398,41 @@ public class ParcelFileDescriptor implements Parcelable, Closeable {
      * @param socket The Socket whose FileDescriptor is used to create
      *               a new ParcelFileDescriptor.
      *
-     * @return A new ParcelFileDescriptor with the FileDescriptor of the
-     *         specified Socket.
+     * @return A new ParcelFileDescriptor with a duped copy of the
+     * FileDescriptor of the specified Socket.
+     *
+     * @throws UncheckedIOException if {@link #dup(FileDescriptor)} throws IOException.
      */
     public static ParcelFileDescriptor fromSocket(Socket socket) {
         FileDescriptor fd = socket.getFileDescriptor$();
-        return fd != null ? new ParcelFileDescriptor(fd) : null;
+        try {
+            return fd != null ? ParcelFileDescriptor.dup(fd) : null;
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
     }
 
     /**
-     * Create a new ParcelFileDescriptor from the specified DatagramSocket.
+     * Create a new ParcelFileDescriptor from the specified DatagramSocket. The
+     * new ParcelFileDescriptor holds a dup of the original FileDescriptor in
+     * the DatagramSocket, so you must still close the DatagramSocket as well
+     * as the new ParcelFileDescriptor.
      *
      * @param datagramSocket The DatagramSocket whose FileDescriptor is used
      *               to create a new ParcelFileDescriptor.
      *
-     * @return A new ParcelFileDescriptor with the FileDescriptor of the
-     *         specified DatagramSocket.
+     * @return A new ParcelFileDescriptor with a duped copy of the
+     * FileDescriptor of the specified Socket.
+     *
+     * @throws UncheckedIOException if {@link #dup(FileDescriptor)} throws IOException.
      */
     public static ParcelFileDescriptor fromDatagramSocket(DatagramSocket datagramSocket) {
         FileDescriptor fd = datagramSocket.getFileDescriptor$();
-        return fd != null ? new ParcelFileDescriptor(fd) : null;
+        try {
+            return fd != null ? ParcelFileDescriptor.dup(fd) : null;
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
     }
 
     /**
@@ -546,7 +562,7 @@ public class ParcelFileDescriptor implements Parcelable, Closeable {
         }
         file.deactivate();
         FileDescriptor fd = file.getFileDescriptor();
-        return fd != null ? new ParcelFileDescriptor(fd) : null;
+        return fd != null ? ParcelFileDescriptor.dup(fd) : null;
     }
 
     /**
-- 
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