Suspicious memory access

[xavierh]

7DaysProfileEditor/7DaysProfileEditor/source/PlayerData/ItemValue.cs

Lines 45 to 49 in c6f09ce

	byte partNumber = reader.ReadByte();
	parts = new ItemValue[4];
	if (partNumber != 0) {
	for (int i = 0; i < (int)partNumber; i++) {

Bare in mind that I do not know C# at all.
parts array is initialized with a size of 4 but can potentially go beyond 4

(I was having a look at the code to implement new feature in https://github.com/nicolas-f/7DTD-leaflet)

[Karlovsky120]

You can only have 4 parts, but you can have any number of accessories. At least I think so.

Is there an item in the game that has more than 4 parts and can be put in inventory semi-assembled (with more than 4 parts assembled)?

I haven't really played the game much lately.

[madmunki]

The array is zero indexed. So 0-4 is five. 4 parts, and a flashlight.

[Karlovsky120]

Wrong.

0-3 iz four since 4 is excluded (notice the <, not <=).

Accessories have a separate array they're stored in.

The code is fine, unless there is a new part cap that is greater than 4.

[xavierh]

The point is, you are assuming that partNumber is between 0-3 (which it should) but it could be anything else as it is read from the file and you potentially would do an index out of bound access. You can not assume that partNumber is between 0 and 3.

Line 49 should be:
for (int i = 0; i < (int)partNumber && i < 4; i++) {

[Karlovsky120]

Sure, it could be changed. But if the number really is greater or equal than 4, something is off with the file and the program will fail reading it one way or another. You get an error either way.