Go is a strongly typed language, it avoids making mistakes.
I wrongly assumed Go was handling integer overflows, and reported an error.
Here is the perfect world where everything works as expected
a := int64(42)
b := uint8(a)
fmt.Println(b) // 42
So what does the following code
a = 255 + 1 // 255 is the higher value an uint8 can reach
b = uint8(a)
fmt.Println(b) // ?
a = -1
b = uint8(a)
fmt.Println(b) // ?
Here is the solution
Spoiler: it doesn't work as expected, or at least as we could expect.
So here Go is doing a silent conversion, of course it cannot store the value in the integer types provided, but there is no panic at all.
There are consequences: CWE-190. Please note CWE-190 is Common Weakness that affects a lot of language, and that is documented since 2006-07-19.
- Imagine you access a resource by its identifier, but you need to convert from an integer type to another, you may allow to access to another resource.
Because of this, gosec a linter focused on improving the security in Go, provided a linter to detect the issue: the linter G115
The G115 linter idea was good.
But it was unfortunately merged with some false issues, that are now addressed, except a few ones.
The problem becomes massive after gosec v2.21.0 was merged into golangci-lint 1.60.2
Many people disabled gosec G115, because of the false positives and noise it was bringing to the CI. They were so numerous false-positives, they couldn't be fixed with a //nolint:gosec // disable G115
directive.
The problem is now (almost) fixed with golangci-lint 1.61.0 (that ships gosec v2.21.2, there are still a few remaining false-positive issues that need to be addressed, but they are less frequent.
Unfortunately, during that 2 weeks delay, many people chose to disable the G115 checker, you can see it easily on GitHub
Maybe, they would enable them back now.