Date: Mon, 5 Mar 2001 16:30:24 -0800 From: Alfred Perlstein <alfred@freebsd.org> To: terry@freebsd.org Cc: audit@freebsd.org Subject: ISO 9660 questions (forw) Re: Could you commit some code for me? Message-ID: <20010305163023.E8663@fw.wintelcom.net>
next in thread | raw e-mail | index | archive | help
In re: http://www.FreeBSD.org/cgi/query-pr.cgi?pr=23315 I was wondering if anyone knew if this was an ok patch? I'm worried about accidentally allowing an admin to mount a disc in a way that would/could cause a panic. Terry, you're Mr FS Standards, care to comment? The combo of tech docs and Linux source crawling that I did to find an answer gave me am major headache. ----- Forwarded message from Mark Peek <mark@whistle.com> ----- From: Mark Peek <mark@whistle.com> To: Alfred Perlstein <alfred@FreeBSD.ORG> Subject: Re: Could you commit some code for me? Date: Thu, 22 Feb 2001 17:42:31 -0800 Message-Id: <p05010401b6bb67685a10@[207.76.207.169]> At 4:56 PM -0800 2/22/01, Alfred Perlstein wrote: >I'll commit this, but i need to know what the extra flags actually mean, >meaning I want to make sure that this doesn't allow mounting of discs >that actually have a different layout/FS that might cause a panic for >others. Alfred, Thanks for getting back to me. I don't have access to the ISO specs but I found this source of information on the Joliet format that appears to be a copy of the Microsoft spec: <http://bmrc.berkeley.edu/people/chaffee/jolspec.html>; It states: >The UCS-2 Level 1, UCS Level 2, and UCS-2 Level 3 escape sequences are >considered to be registered according ISO 2735 for purposes of setting >bit 0 of the Volume Flags field of the SVD. > >The nominal value of Bit 0 of the Volume Flags field for a Unicode SVD >shall be ZERO. I'm not entirely sure what it means to have these escape sequences "registered". The problem is some Joliet CD's will have the correct escape sequences but they fail to properly clear the volume flags bit zero. The current FreeBSD driver checks this bit and will revert back to level 0 (8.3 filenames) if it is set. This same CD (and others I've seen) provide full filenames on Windows and Linux. Note: by inspection of the source code, the Linux driver does not check this bit field. It really appears to be a nuance to the 9660 and Joliet formats. I'm not too worried about a Rock Ridge disk all of a sudden showing up as a Joliet volume. Also, as I stated in my PR, you can use the -j to mount_cd9660 to turn off all Joliet behavior. Does that help alleviate your concerns? Let me know if you have any other questions or comments. Thanks, Mark --------- Mark Peek Director of Internet Technology IBM Global Small Business/Whistle Communications Work: (650) 577-7052 Email: mark@whistle.com ----- End forwarded message ----- -- -Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org] To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-audit" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20010305163023.E8663>