commit ceb30493c7ea9f2c6925e17cc0626396de8f8080
author Ivan Lozano <ivanlozano@google.com> Tue Jan 02 21:01:16 2018 +0000
committer Ivan Lozano <ivanlozano@google.com> Fri Jan 12 16:51:53 2018 -0800
tree a01a39b7b1a29ba3538e673559431b15c1b4fa0d
parent 46d5355af96d582b81d6fae0ff1d3ceb745863f5

Fix integer overflow sanitizer in FastThread.cpp.

Fix the integer overflow sanitizer in the FastThread threadLoop()
function by using the builtin overflow-safe function.

 runtime error: unsigned integer overflow: 4294934528 + 65536 cannot be
 represented in type 'unsigned int'

Bug: 30969751
Test: Builds and boots.
Change-Id: I86e20932fb288deebe4fb778a689cf71eea6be79
Merged-In: I86e20932fb288deebe4fb778a689cf71eea6be79
(cherry picked from commit 77657148b366c0c73bd942d7c67abc8bba8a8300)

services/audioflinger/FastThread.cpp

diff --git a/services/audioflinger/FastThread.cpp b/services/audioflinger/FastThread.cpp
index 85865b7..dc15487 100644
--- a/services/audioflinger/FastThread.cpp
+++ b/services/audioflinger/FastThread.cpp
@@ -297,7 +297,8 @@
                     size_t i = mBounds & (mDumpState->mSamplingN - 1);
                     mBounds = (mBounds & 0xFFFF0000) | ((mBounds + 1) & 0xFFFF);
                     if (mFull) {
-                        mBounds += 0x10000;
+                        //mBounds += 0x10000;
+                        __builtin_add_overflow(mBounds, 0x10000, &mBounds);
                     } else if (!(mBounds & (mDumpState->mSamplingN - 1))) {
                         mFull = true;
                     }