commit 5663ce91529a5a2b58cf4eff151ee7fb442f207c
author Minyue Li <minyue@webrtc.org> Thu Apr 22 22:58:24 2021
committer Commit Bot <commit-bot@chromium.org> Fri Apr 23 07:49:24 2021
tree 2f974c6c79a99435421b54b90c58b79446107d4d
parent 6674b9879a94163c2922d5a8a85509edf64dfd04

Avoid undefined behavior in a division operation.

BUG: webrtc:5486
Change-Id: I2850fbec3283b81b49ee4f966349a94aabc2bf82
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/215969
Reviewed-by: Henrik Lundin <henrik.lundin@webrtc.org>
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Commit-Queue: Minyue Li <minyue@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33811}

common_audio/signal_processing/division_operations.c

diff --git a/common_audio/signal_processing/division_operations.c b/common_audio/signal_processing/division_operations.c
index c6195e7..4764ddf 100644
--- a/common_audio/signal_processing/division_operations.c
+++ b/common_audio/signal_processing/division_operations.c
@@ -98,8 +98,7 @@
     return div;
 }
 
-int32_t RTC_NO_SANITIZE("signed-integer-overflow")  // bugs.webrtc.org/5486
-WebRtcSpl_DivW32HiLow(int32_t num, int16_t den_hi, int16_t den_low)
+int32_t WebRtcSpl_DivW32HiLow(int32_t num, int16_t den_hi, int16_t den_low)
 {
     int16_t approx, tmp_hi, tmp_low, num_hi, num_low;
     int32_t tmpW32;
@@ -111,8 +110,8 @@
     tmpW32 = (den_hi * approx << 1) + ((den_low * approx >> 15) << 1);
     // tmpW32 = den * approx
 
-    tmpW32 = (int32_t)0x7fffffffL - tmpW32; // result in Q30 (tmpW32 = 2.0-(den*approx))
-    // UBSan: 2147483647 - -2 cannot be represented in type 'int'
+    // result in Q30 (tmpW32 = 2.0-(den*approx))
+    tmpW32 = (int32_t)((int64_t)0x7fffffffL - tmpW32);
 
     // Store tmpW32 in hi and low format
     tmp_hi = (int16_t)(tmpW32 >> 16);