Authentication Cache + Storage crash application

[MFranceschi6]

Describe the issue

Application crash because of a req.auth.require(Something.self)

Vapor version

4.84.2

Operating system and version

macos 14.4.1 (23E224) apple m2

Swift version

Swift Package Manager - Swift 5.10.0-dev

Steps to reproduce

create a simple Vapor application and use this as handle and build in release mode.

struct Test: Authenticatable { }

func test(req: Request) async throws -> Response {
    await withThrowingTaskGroup(of: Void.self)  { group in
	for i in (0...5) {
	    group.addTask {
		try? req.auth.require(Test.self)
	    }
	}
    }

    return .init()
}

call the handle, usually around the second call it crashes.

I've dug into the code and I've found that the problem is the following pattern inside a concurrently executing code

if let existing = req.storage.get(Test.self) {
    req.logger.info("get")
} else {
    req.storage[Test.self] = .init()
    req.logger.info("Set")
}

This is exactly what we find here

vapor/Sources/Vapor/Authentication/AuthenticationCache.swift

Lines 84 to 97 in 11cdb29

	private var cache: Cache {
	get {
	if let existing = self.request.storage[CacheKey.self] {
	return existing
	} else {
	let new = Cache()
	self.request.storage[CacheKey.self] = new
	return new
	}
	}
	set {
	self.request.storage[CacheKey.self] = newValue
	}
	}

Something like this fixes the issue, but I suppose it's too simple of a solution and also I don't know the performances impact it may have.

let lock: NIOLock = .init()
lock.withLock {
	if let existing = req.storage.get(Test.self) {
		req.logger.info("get")
	} else {
		req.storage[Test.self] = .init()
		req.logger.info("Set")
	}
}

Outcome

The program goes boom 😄

Additional notes

The same issue arises in an amazon linux 2 container with swift 5.7

[0xTim]

@MFranceschi6 have you tried the latest version of Vapor? These should all be fixed in 4.86.0

[MFranceschi6]

@0xTim thank you very much, I also did a swift package update before testing the bug.
I don't know why it didn't update the version of vapor.

Yep, now I've 4.92.5 and it works flawlessly thank you again