[DO NOT MERGE] AMR WB encoder: prevent OOB write in ACELP_4t64_fx

In ACELP_4t64_fx, when iterating over ind array, check index against
  array size to prevent OOB write, log an error if such an access
  was about to happen.

Bug 132647222
Test: atest EncoderTest#testAMRWBEncoders
Merged-in: I33f476d94baec2feffc7bcccd0ad0481b8452518

Change-Id: I814a05217f20ea3b941deddb70edb31cd342de6b

media/libstagefright/codecs/amrwbenc/Android.mk

@@ -92,7 +92,8 @@ LOCAL_ARM_MODE := arm
 
 LOCAL_STATIC_LIBRARIES :=
 
-LOCAL_SHARED_LIBRARIES :=
+LOCAL_SHARED_LIBRARIES := \
+        liblog
 
 LOCAL_C_INCLUDES := \
 	frameworks/av/include \

media/libstagefright/codecs/amrwbenc/SampleCode/Android.mk

@@ -14,7 +14,8 @@ LOCAL_CFLAGS :=
 
 LOCAL_SHARED_LIBRARIES := \
     libstagefright \
-    libdl
+    libdl \
+    liblog
 
 LOCAL_STATIC_LIBRARIES := \
     libstagefright_amrwbenc

media/libstagefright/codecs/amrwbenc/src/c4t64fx.c

@@ -47,6 +47,10 @@
 
 #include "q_pulse.h"
 
+#undef LOG_TAG
+#define LOG_TAG "amrwbenc"
+#include <log/log.h>
+
 static Word16 tipos[36] = {
     0, 1, 2, 3,                            /* starting point &ipos[0], 1st iter */
     1, 2, 3, 0,                            /* starting point &ipos[4], 2nd iter */
@@ -745,11 +749,16 @@ void ACELP_4t64_fx(
 
         i = (Word16)((vo_L_mult(track, NPMAXPT) >> 1));
 
-        while (ind[i] >= 0)
+        while (i < NPMAXPT * NB_TRACK && ind[i] >= 0)
         {
             i += 1;
         }
-        ind[i] = index;
+        if (i < NPMAXPT * NB_TRACK) {
+            ind[i] = index;
+        } else {
+            ALOGE("b/132647222, OOB access in ind array track=%d i=%d", track, i);
+            android_errorWriteLog(0x534e4554, "132647222");
+        }
     }
 
     k = 0;