Why ext4?
Why ext4?
Posted Oct 9, 2020 3:45 UTC (Fri) by epa (subscriber, #39769)In reply to: Why ext4? by sfeam
Parent article: The ABI status of filesystem formats
ISO 9660 has a standard formally specifying it. That means you can decide whether a given file system image is valid, and if the kernel doesn’t work with a valid image, that is clearly a kernel bug. So no, it doesn’t quite have the same general problem as ext4.
In principle the point still stands: there could be a bug in the kernel code when handling a malformed file system image, and that bug could cause security problems, yet somebody might be relying on the exiting behaviour because they use one of these malformed images. But that seems much less likely with ISO 9660, partly because it’s much simpler than ext4, and partly because it’s understood by many different OSes, so you’d soon find out if your image depended on a Linux-specific quirk.
I have a CD-ROM that’s meant to be in ISO 9660 format but many of the filenames contain the / character. Linux does not handle this well. But it’s clearly incorrect by the standard, so you can say this is no bug in Linux.