Impose a size bound for dynamically allocated tables in stbl.

Impose a restriction of 200MiB for tables in stsc, stts, ctts and stss
boxes. Also change mTimeToSample from Vector to array.

Bug: 29367429
Change-Id: I953bea9fe0590268cf27376740f582dc88563d42
(cherry picked from commit 583a012)

Author: Pawin Vongmasa

media/libstagefright/SampleTable.cpp

@@ -123,7 +123,7 @@ SampleTable::SampleTable(const sp<DataSource> &source)
       mNumSampleSizes(0),
       mHasTimeToSample(false),
       mTimeToSampleCount(0),
-      mTimeToSample(),
+      mTimeToSample(NULL),
       mSampleTimeEntries(NULL),
       mCompositionTimeDeltaEntries(NULL),
       mNumCompositionTimeDeltaEntries(0),
@@ -132,7 +132,8 @@ SampleTable::SampleTable(const sp<DataSource> &source)
       mNumSyncSamples(0),
       mSyncSamples(NULL),
       mLastSyncSampleIndex(0),
-      mSampleToChunkEntries(NULL) {
+      mSampleToChunkEntries(NULL),
+      mTotalSize(0) {
     mSampleIterator = new SampleIterator(this);
 }
 
@@ -143,6 +144,9 @@ SampleTable::~SampleTable() {
     delete[] mSyncSamples;
     mSyncSamples = NULL;
 
+    delete[] mTimeToSample;
+    mTimeToSample = NULL;
+
     delete mCompositionDeltaLookup;
     mCompositionDeltaLookup = NULL;
 
@@ -233,11 +237,43 @@ status_t SampleTable::setSampleToChunkParams(
         return ERROR_MALFORMED;
     }
 
-    if (SIZE_MAX / sizeof(SampleToChunkEntry) <= mNumSampleToChunkOffsets)
+    if ((uint64_t)SIZE_MAX / sizeof(SampleToChunkEntry) <=
+            (uint64_t)mNumSampleToChunkOffsets) {
+        ALOGE("Sample-to-chunk table size too large.");
         return ERROR_OUT_OF_RANGE;
+    }
+
+    mTotalSize += (uint64_t)mNumSampleToChunkOffsets *
+            sizeof(SampleToChunkEntry);
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Sample-to-chunk table size would make sample table too large.\n"
+              "    Requested sample-to-chunk table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)mNumSampleToChunkOffsets *
+                      sizeof(SampleToChunkEntry),
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return ERROR_OUT_OF_RANGE;
+    }
 
     mSampleToChunkEntries =
-        new SampleToChunkEntry[mNumSampleToChunkOffsets];
+        new (std::nothrow) SampleToChunkEntry[mNumSampleToChunkOffsets];
+    if (!mSampleToChunkEntries) {
+        ALOGE("Cannot allocate sample-to-chunk table with %llu entries.",
+                (unsigned long long)mNumSampleToChunkOffsets);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    if (mNumSampleToChunkOffsets == 0) {
+        return OK;
+    }
+
+    if ((off64_t)(SIZE_MAX - 8 -
+            ((mNumSampleToChunkOffsets - 1) * sizeof(SampleToChunkEntry)))
+            < mSampleToChunkOffset) {
+        return ERROR_MALFORMED;
+    }
 
     for (uint32_t i = 0; i < mNumSampleToChunkOffsets; ++i) {
         uint8_t buffer[12];
@@ -246,8 +282,11 @@ status_t SampleTable::setSampleToChunkParams(
                 != (ssize_t)sizeof(buffer)) {
             return ERROR_IO;
         }
-
-        CHECK(U32_AT(buffer) >= 1);  // chunk index is 1 based in the spec.
+        // chunk index is 1 based in the spec.
+        if (U32_AT(buffer) < 1) {
+            ALOGE("b/23534160");
+            return ERROR_OUT_OF_RANGE;
+        }
 
         // We want the chunk index to be 0-based.
         mSampleToChunkEntries[i].startChunk = U32_AT(buffer) - 1;
@@ -347,20 +386,41 @@ status_t SampleTable::setTimeToSampleParams(
         // 2) mTimeToSampleCount is the number of entries of the time-to-sample
         //    table.
         // 3) We hope that the table size does not exceed UINT32_MAX.
-        ALOGE("  Error: Time-to-sample table size too large.");
+        ALOGE("Time-to-sample table size too large.");
         return ERROR_OUT_OF_RANGE;
     }
 
     // Note: At this point, we know that mTimeToSampleCount * 2 will not
     // overflow because of the above condition.
-    if (!mDataSource->getVector(data_offset + 8, &mTimeToSample,
-                                mTimeToSampleCount * 2)) {
-        ALOGE("  Error: Incomplete data read for time-to-sample table.");
+
+    uint64_t allocSize = (uint64_t)mTimeToSampleCount * 2 * sizeof(uint32_t);
+    mTotalSize += allocSize;
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Time-to-sample table size would make sample table too large.\n"
+              "    Requested time-to-sample table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)allocSize,
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mTimeToSample = new (std::nothrow) uint32_t[mTimeToSampleCount * 2];
+    if (!mTimeToSample) {
+        ALOGE("Cannot allocate time-to-sample table with %llu entries.",
+                (unsigned long long)mTimeToSampleCount);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    if (mDataSource->readAt(data_offset + 8, mTimeToSample,
+            (size_t)allocSize) < (ssize_t)allocSize) {
+        ALOGE("Incomplete data read for time-to-sample table.");
         return ERROR_IO;
     }
 
-    for (size_t i = 0; i < mTimeToSample.size(); ++i) {
-        mTimeToSample.editItemAt(i) = ntohl(mTimeToSample[i]);
+    for (size_t i = 0; i < mTimeToSampleCount * 2; ++i) {
+        mTimeToSample[i] = ntohl(mTimeToSample[i]);
     }
 
     mHasTimeToSample = true;
@@ -396,14 +456,31 @@ status_t SampleTable::setCompositionTimeToSampleParams(
     mNumCompositionTimeDeltaEntries = numEntries;
     uint64_t allocSize = (uint64_t)numEntries * 2 * sizeof(uint32_t);
     if (allocSize > SIZE_MAX) {
+        ALOGE("Composition-time-to-sample table size too large.");
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mTotalSize += allocSize;
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Composition-time-to-sample table would make sample table too large.\n"
+              "    Requested composition-time-to-sample table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)allocSize,
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
         return ERROR_OUT_OF_RANGE;
     }
 
-    mCompositionTimeDeltaEntries = new uint32_t[2 * numEntries];
+    mCompositionTimeDeltaEntries = new (std::nothrow) uint32_t[2 * numEntries];
+    if (!mCompositionTimeDeltaEntries) {
+        ALOGE("Cannot allocate composition-time-to-sample table with %llu "
+                "entries.", (unsigned long long)numEntries);
+        return ERROR_OUT_OF_RANGE;
+    }
 
-    if (mDataSource->readAt(
-                data_offset + 8, mCompositionTimeDeltaEntries, numEntries * 8)
-            < (ssize_t)numEntries * 8) {
+    if (mDataSource->readAt(data_offset + 8, mCompositionTimeDeltaEntries,
+            (size_t)allocSize) < (ssize_t)allocSize) {
         delete[] mCompositionTimeDeltaEntries;
         mCompositionTimeDeltaEntries = NULL;
 
@@ -444,15 +521,33 @@ status_t SampleTable::setSyncSampleParams(off64_t data_offset, size_t data_size)
         ALOGV("Table of sync samples is empty or has only a single entry!");
     }
 
-    uint64_t allocSize = mNumSyncSamples * (uint64_t)sizeof(uint32_t);
+    uint64_t allocSize = (uint64_t)mNumSyncSamples * sizeof(uint32_t);
     if (allocSize > SIZE_MAX) {
+        ALOGE("Sync sample table size too large.");
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mTotalSize += allocSize;
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Sync sample table size would make sample table too large.\n"
+              "    Requested sync sample table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)allocSize,
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mSyncSamples = new (std::nothrow) uint32_t[mNumSyncSamples];
+    if (!mSyncSamples) {
+        ALOGE("Cannot allocate sync sample table with %llu entries.",
+                (unsigned long long)mNumSyncSamples);
         return ERROR_OUT_OF_RANGE;
     }
 
-    mSyncSamples = new uint32_t[mNumSyncSamples];
-    size_t size = mNumSyncSamples * sizeof(uint32_t);
-    if (mDataSource->readAt(mSyncSampleOffset + 8, mSyncSamples, size)
-            != (ssize_t)size) {
+    if (mDataSource->readAt(mSyncSampleOffset + 8, mSyncSamples,
+            (size_t)allocSize) != (ssize_t)allocSize) {
         return ERROR_IO;
     }
 
@@ -517,7 +612,24 @@ void SampleTable::buildSampleEntriesTable() {
         return;
     }
 
-    mSampleTimeEntries = new SampleTimeEntry[mNumSampleSizes];
+    mTotalSize += (uint64_t)mNumSampleSizes * sizeof(SampleTimeEntry);
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Sample entry table size would make sample table too large.\n"
+              "    Requested sample entry table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)mNumSampleSizes * sizeof(SampleTimeEntry),
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return;
+    }
+
+    mSampleTimeEntries = new (std::nothrow) SampleTimeEntry[mNumSampleSizes];
+    if (!mSampleTimeEntries) {
+        ALOGE("Cannot allocate sample entry table with %llu entries.",
+                (unsigned long long)mNumSampleSizes);
+        return;
+    }
 
     uint32_t sampleIndex = 0;
     uint32_t sampleTime = 0;

media/libstagefright/include/SampleTable.h

@@ -24,7 +24,6 @@
 #include <media/stagefright/MediaErrors.h>
 #include <utils/RefBase.h>
 #include <utils/threads.h>
-#include <utils/Vector.h>
 
 namespace android {
 
@@ -94,6 +93,9 @@ class SampleTable : public RefBase {
     static const uint32_t kSampleSizeType32;
     static const uint32_t kSampleSizeTypeCompact;
 
+    // Limit the total size of all internal tables to 200MiB.
+    static const size_t kMaxTotalSize = 200 * (1 << 20);
+
     sp<DataSource> mDataSource;
     Mutex mLock;
 
@@ -111,7 +113,7 @@ class SampleTable : public RefBase {
 
     bool mHasTimeToSample;
     uint32_t mTimeToSampleCount;
-    Vector<uint32_t> mTimeToSample;
+    uint32_t* mTimeToSample;
 
     struct SampleTimeEntry {
         uint32_t mSampleIndex;
@@ -137,6 +139,9 @@ class SampleTable : public RefBase {
     };
     SampleToChunkEntry *mSampleToChunkEntries;
 
+    // Approximate size of all tables combined.
+    uint64_t mTotalSize;
+
     friend struct SampleIterator;
 
     status_t getSampleSize_l(uint32_t sample_index, size_t *sample_size);