tree 612e087fd57857950ef0e14f199378ae87c125cb
parent 237d3e55cdfbefe8df210aed32f315909325b4ab
author Luke Huang <huangluke@google.com> 1560269280 -0700
committer Luke Huang <huangluke@google.com> 1560274419 +0000

Fix race condition caused by fd reused for DnsResolver

There might be a gap between fd close and fd event listener unregister.
If fd is reused for another query during that gap, it might cause the
query failed with no response since addOnFileDescriptorEventListener
method failed. To fix this problem, we must ensure that fd event
listener is unregistered before fd closing.

Bug: 134310704
Test: atest DnsResolverTest

Merged-In: I443bb11b15845b079ee4370a7797e692e62fa3c8
(cherry picked from commit 07de4cf82ac09f8b9f37afa9eb1b7a44b43b6fe6)

Change-Id: I7041e67d8c906cbf88050e7d94245f8e15dcdbb4