On Thu, 20 Apr 2023 10:57:07 GMT, Aleksey Shipilev <sh...@openjdk.org> wrote:
>> This issue was reported by: Yakov Shafranovich >> ([yako...@amazon.com](mailto:yako...@amazon.com)) >> >> Currently, `ObjectInputStream::readObject()` doesn't explicitly checks for a >> negative array length in the deserialization stream. Instead it calls >> `j.l.r.Array::newInstance(..)` with the negative length which results in a >> `NegativeArraySizeException`. NegativeArraySizeException is an unchecked >> exception which is neither declared in the signature of >> `ObjectInputStream::readObject()` nor mentioned in its API specification. It >> is therefore not obvious for users of `ObjectInputStream::readObject()` that >> they may have to handle `NegativeArraySizeException`s. It would therefor be >> better if a negative array length in the deserialization stream would be >> automatically wrapped in an `InvalidClassException` which is a checked >> exception (derived from `IOException` via `ObjectStreamException`) and >> declared in the signature of `ObjectInputStream::readObject()`. >> >> If we do the negative array length check in >> `ObjectInputStream::readObject()` before filtering, this will then also fix >> `ObjectInputFilter.FilterInfo::arrayLength()` which is defined as: >> >> Returns: >> the non-negative number of array elements when deserializing an array of the >> class, otherwise -1 >> >> but currently returns a negative value if the array length is negative. > > src/java.base/share/classes/java/io/ObjectInputStream.java line 2142: > >> 2140: int len = bin.readInt(); >> 2141: if (len < 0) { >> 2142: throw new InvalidClassException(desc.getName(), "Array >> length < 0 (" + len + ")"); > > Suggestion: > > throw new InvalidClassException(desc.getName(), "Array length (" > + len + ") is negative"); I'd keep the exception logic simple/minimal. Especially since this is a manual and exceptional case that is not the result of any input provided through an API. throw new InvalidClassException(desc.getName(), "Array length is negative"); ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/13540#discussion_r1172965774
