Jonathan Coates 1255bd00fd Fix mounts being usable after a disk is ejected ... This probably fails "responsible disclosure", but it's not an RCE and frankly the whole bug is utterly hilarious so here we are... It's possible to open a file on a disk drive and continue to read/write to them after the disk has been removed: local disk = peripheral.find("drive") local input = fs.open(fs.combine(disk.getMountPath(), "stream"), "rb") local output = fs.open(fs.combine(disk.getMountPath(), "stream"), "wb") disk.ejectDisk() -- input/output can still be interacted with. This is pretty amusing, as now it allows us to move the disk somewhere else and repeat - we've now got a private tunnel which two computers can use to communicate. Fixing this is intuitively quite simple - just close any open files belonging to this mount. However, this is where things get messy thanks to the wonderful joy of how CC's streams are handled. As things stand, the filesystem effectively does the following flow:: - There is a function `open : String -> Channel' (file modes are irrelevant here). - Once a file is opened, we transform it into some <T extends Closeable>. This is, for instance, a BufferedReader. - We generate a "token" (i.e. FileSystemWrapper<T>), which we generate a week reference to and map it to a tuple of our Channel and T. If this token is ever garbage collected (someone forgot to call close() on a file), then we close our T and Channel. - This token and T are returned to the calling function, which then constructs a Lua object. The problem here is that if we close the underlying Channel+T before the Lua object calls .close(), then it won't know the underlying channel is closed, and you get some pretty ugly errors (e.g. "Stream Closed"). So we've moved the "is open" state into the FileSystemWrapper<T>. The whole system is incredibly complex at this point, and I'd really like to clean it up. Ideally we could treat the HandleGeneric as the token instead - this way we could potentially also clean up FileSystemWrapperMount. BBut something to play with in the future, and not when it's 10:30pm. --- All this wall of text, and this isn't the only bug I've found with disks today :/.		2021-01-13 22:10:44 +00:00
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java/dan200/computercraft	Fix mounts being usable after a disk is ejected	2021-01-13 22:10:44 +00:00
resources	Make rightAlt only close menu, never open it. (#672)	2021-01-11 21:59:29 +00:00