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https://issues.apache.org/jira/browse/PARQUET-2164?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17691348#comment-17691348
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ASF GitHub Bot commented on PARQUET-2164:
-----------------------------------------

wgtmac commented on code in PR #1032:
URL: https://github.com/apache/parquet-mr/pull/1032#discussion_r1112489810


##########
parquet-common/src/main/java/org/apache/parquet/bytes/CapacityByteArrayOutputStream.java:
##########
@@ -164,6 +164,12 @@ public CapacityByteArrayOutputStream(int initialSlabSize, 
int maxCapacityHint, B
   private void addSlab(int minimumSize) {
     int nextSlabSize;
 
+    if (bytesUsed + minimumSize < 0) {

Review Comment:
   nit: replace it with `Math.addExact` to hand over overflow check. Then we 
get the chance to check the 2GB hard limit before it becoming negative





> CapacityByteArrayOutputStream overflow while writing causes negative row 
> group sizes to be written
> --------------------------------------------------------------------------------------------------
>
>                 Key: PARQUET-2164
>                 URL: https://issues.apache.org/jira/browse/PARQUET-2164
>             Project: Parquet
>          Issue Type: Bug
>          Components: parquet-mr
>    Affects Versions: 1.12.2
>            Reporter: Parth Chandra
>            Priority: Major
>             Fix For: 1.12.3
>
>         Attachments: TestLargeDictionaryWriteParquet.java
>
>
> It is possible, while writing a parquet file, to cause 
> {{CapacityByteArrayOutputStream}} to overflow.
> This is an extreme case but it has been observed in a real world data set.
> The attached Spark program manages to reproduce the issue.
> Short summary of how this happens - 
> 1. After many small records possibly including nulls, the dictionary page 
> fills up and subsequent pages are written using plain encoding
> 2. The estimate of when to perform the page size check is based on the number 
> of values observed per page so far. Let's say this is about 100K
> 3. A sequence of very large records shows up. Let's say each of these record 
> is 200K. 
> 4. After 11K of these records the size of the page has gone up beyond 2GB.
> 5. {{CapacityByteArrayOutputStream}} is capable of holding more than 2GB of 
> data but also it holds the size of the data in an int which overflows.
> There are a couple of things to fix here -
> 1. The check for page size should check both the number of values added as 
> well as the buffered size of the data
> 2. {{CapacityByteArrayOutputStream}} should throw an exception is the data 
> size increases beyond 2GB ({{java.io.ByteArrayOutputStream}} does exactly 
> that).



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