Comment 14 for bug 72872

I'm not an expert on CD/DVD file systems, but it seems to me that we need to nail down the real technical issues here (and whether this is actually a bug -- see below). From my (limited) understanding:

-- CDs/DVDs are typically burnt with ISO 9660 filesystems and most OSs support (some aspects of) the Joliet and Rock Ridge extensions

-- the Rock Ridge extensions include UNIX file permission details

-- Mac OS X, in some circumstances, burns an HFS Plus (Mac OS Extended) / ISO 9660 hybrid format. See http://support.apple.com/kb/TA21176?viewlocale=en_US :

"With Mac OS X 10.2.8 or earlier, DVD-R discs burned in the Finder are Mac OS Extended format (HFS Plus). With Mac OS X 10.3 or later, they are a HFS Plus/ISO 9660 hybrid format, which can be read by most computer systems, including Microsoft Windows. The disc contains these filesystems: HFS+, ISO-9660 with Rock Ridge, and Joliet with Rock Ridge."

I don't know/understand the full details of Linux Rock Ridge support, but doesn't this bug depend on an understanding of this? Either:

a) the disc is Rock Ridge with permissions which Linux is *correctly* honouring
(i.e. not a bug; this assumes that this is how Rock Ridge is supposed to work, both in general and on Linux)

b) as (a) but Linux should not honour them in certain cases and this represents one of those cases (i.e. an incorrect/incomplete support of the Rock Ridge standards; question is what's specific about these discs to cause this not to work)

c) the disc has permissions reflected in some other way (e.g. the hybrid mentioned earlier) and Linux is correctly honouring them (e.g. as per HFS Plus or whatever). *Possibly* no bug, unless it's taken that this honouring is non-sensical in this case (e.g. for Mac OS X specific permissions when you're not reading it on OS X)

d) Linux is incorrectly interpreting some file system data as implying permissions when it doesn't (so issue is a deeper file system interpretation and standards support one, and question as in (b) applies)

e) something else (OK, I copped out here!)

Hope this might help others progress this. Unfortunately, I don't have/remember which disc caused me this problem originally....