diff --git a/lang/java/avro/src/main/java/org/apache/avro/SystemLimitException.java b/lang/java/avro/src/main/java/org/apache/avro/SystemLimitException.java index a96f812d84d..b4e46834599 100644 --- a/lang/java/avro/src/main/java/org/apache/avro/SystemLimitException.java +++ b/lang/java/avro/src/main/java/org/apache/avro/SystemLimitException.java @@ -153,6 +153,35 @@ public static int checkMaxCollectionLength(long existing, long items) { return (int) length; } + /** + * Check to ensure that reading the specified number of items remains within the + * specified limits. + * + * @param items The next number of items to read. In normal usage, this is + * always a positive, permitted value. Negative and zero values + * have a special meaning in Avro decoding. + * @return The total number of items in the collection if and only if it is + * within the limit and non-negative. + * @throws UnsupportedOperationException if reading the items would allocate a + * collection that the Java VM would be + * unable to handle + * @throws SystemLimitException if the decoding should fail because it + * would otherwise result in an allocation + * exceeding the set limit + * @throws AvroRuntimeException if the length is negative + */ + public static int checkMaxCollectionLength(long items) { + if (items > MAX_ARRAY_VM_LIMIT) { + throw new UnsupportedOperationException( + "Cannot read collections larger than " + MAX_ARRAY_VM_LIMIT + " items in Java library"); + } + if (items > maxCollectionLength) { + throw new SystemLimitException( + "Collection length " + items + " exceeds the maximum allowed of " + maxCollectionLength); + } + return (int) items; + } + /** * Check to ensure that reading the string size is within the specified limits. * diff --git a/lang/java/avro/src/main/java/org/apache/avro/io/BinaryDecoder.java b/lang/java/avro/src/main/java/org/apache/avro/io/BinaryDecoder.java index 7217be3addd..865bc9c06c2 100644 --- a/lang/java/avro/src/main/java/org/apache/avro/io/BinaryDecoder.java +++ b/lang/java/avro/src/main/java/org/apache/avro/io/BinaryDecoder.java @@ -428,7 +428,7 @@ private long doSkipItems() throws IOException { @Override public long readArrayStart() throws IOException { - collectionCount = SystemLimitException.checkMaxCollectionLength(0L, doReadItemCount()); + collectionCount = SystemLimitException.checkMaxCollectionLength(doReadItemCount()); return collectionCount; } @@ -446,7 +446,7 @@ public long skipArray() throws IOException { @Override public long readMapStart() throws IOException { - collectionCount = SystemLimitException.checkMaxCollectionLength(0L, doReadItemCount()); + collectionCount = SystemLimitException.checkMaxCollectionLength(doReadItemCount()); return collectionCount; }