commit e34eae2de7bd6dcba5dea132dabb09f63ac46adc
author Dan Austin <danielaustin@google.com> Tue Oct 27 16:14:52 2015 -0700
committer Dan Austin <danielaustin@google.com> Wed Oct 28 19:44:28 2015 +0000
tree f1eb25e6df17d3ef526b9baa7dfc3d1c2dd2c3d9
parent 58fdf7cc01a5b81d40c0bb2f0aeb7c4d23ae5244

Refactor setPlaybackRate to avoid benign unsigned integer overflow.

There is a check that results in a benign unsigned integer overflow.
This has been refactored to avoid the unsigned integer overflow.

Bug: 25327431
Change-Id: Ib112a7cd585c680f13e4bee3d7e9f45da7d66f1d

media/libmedia/AudioTrack.cpp

diff --git a/media/libmedia/AudioTrack.cpp b/media/libmedia/AudioTrack.cpp
index b049895..b8b12d4 100644
--- a/media/libmedia/AudioTrack.cpp
+++ b/media/libmedia/AudioTrack.cpp
@@ -822,13 +822,13 @@
     }
 
     // Check resampler ratios are within bounds
-    if (effectiveRate > mSampleRate * AUDIO_RESAMPLER_DOWN_RATIO_MAX) {
+    if ((uint64_t)effectiveRate > (uint64_t)mSampleRate * (uint64_t)AUDIO_RESAMPLER_DOWN_RATIO_MAX) {
         ALOGV("setPlaybackRate(%f, %f) failed. Resample rate exceeds max accepted value",
                 playbackRate.mSpeed, playbackRate.mPitch);
         return BAD_VALUE;
     }
 
-    if (effectiveRate * AUDIO_RESAMPLER_UP_RATIO_MAX < mSampleRate) {
+    if ((uint64_t)effectiveRate * (uint64_t)AUDIO_RESAMPLER_UP_RATIO_MAX < (uint64_t)mSampleRate) {
         ALOGV("setPlaybackRate(%f, %f) failed. Resample rate below min accepted value",
                         playbackRate.mSpeed, playbackRate.mPitch);
         return BAD_VALUE;