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[Java] Check var-data string length against the buffer before allocating - #1150
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| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
| final int headerLength = 2; | ||
| final int limit = parentMessage.limit(); | ||
| final int dataLength = (buffer.getShort(limit, BYTE_ORDER) & 0xFFFF); | ||
| if (dataLength < 0 || dataLength > buffer.capacity() - limit - headerLength) |
…ing. The generated String accessor must reject a length that is negative or runs past the buffer before it allocates the temporary byte[] or moves the limit; checking after the allocation lets the wire size it.
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The generated String accessor for var data allocated a byte[] of the wire length and advanced the limit before anything checked that length against the buffer, so a frame whose length prefix is negative or far larger than the message made the decoder allocate up to 2 GB, or fail with OutOfMemoryError, before it read past the buffer. The accessor now rejects such a length with IndexOutOfBoundsException before allocating or moving the limit. The IR codecs are regenerated with the same check.
The other var-data accessors (skip, wrap, Appendable) do not allocate and still rely on the buffer's own bounds checks.
Part of #969.
Verified: VarDataStringLengthTest fails on master (OutOfMemoryError: Requested array size exceeds VM limit) and passes here; sbe-tool checkstyle, tests and verifyJavaIrCodecsInSync pass.