On Apr 19, 2012, at 8:58 PM, Rick Macklem <rmack...@uoguelph.ca> wrote:
> Mark Saad wrote: >> On Thu, Apr 19, 2012 at 3:51 PM, Andrew Duane <adu...@juniper.net> >> wrote: >>> MNAMELEN is used to bound the Mount NAMe LENgth, and is used in many >>> many places. It may seem to work fine, but there are lots of >>> utilities and such that will almost certainly fail managing it. >>> Search the source code for MNAMELEN..... >> >> I see that this is used in a number of Mount and fs bits. Do you know >> why mount_nfs would care how long the exported path and hostname are ? >> > Well, it's copied to f_mntfromname in "struct statfs". If one longer > than MNAMELEN is allowed, it gets truncated when copied. I have no idea > which userland apps. will get upset with a truncated value in > f_mntfromname. (To change the size of f_mntfromname would require a new > revision of the statfs syscall, I think?) > > Does this answer what you were asking? rick > Yes and no, it smells like a bug ,in so far as its not mentioned anywhere out there . A one line addition to mount_nfs man page stipulating that there is a known limit on the length of the host name and source export would be helpful. On the other hand 88 bytes seams like an odd size to me . The check for the size happens twice in the 7-stable code ,for mount_nfs, and only once in the 9-stable code . Not sure why either, and i did bot research it yet. In the mean time I am going to take a peak at the other bsd's and see if there is a solution . >>> >>> ................................... >>> Andrew Duane >>> Juniper Networks >>> +1 978-589-0551 (o) >>> +1 603-770-7088 (m) >>> adu...@juniper.net >>> >>> >>> >>> >>>> -----Original Message----- >>>> From: owner-freebsd-hack...@freebsd.org [mailto:owner-freebsd- >>>> hack...@freebsd.org] On Behalf Of Mark Saad >>>> Sent: Thursday, April 19, 2012 3:46 PM >>>> To: freebsd-hackers@freebsd.org >>>> Subject: mount_nfs does not like exports longer then 88 chars >>>> >>>> Hello Hackers >>>> I was wondering if anyone has come across this issue. This exists >>>> in >>>> FreeBSD 6, 7, and 9 , and probably in 8 but I am not using it at >>>> this time. >>>> When a nfs export path and host name total to more then 88 >>>> characters >>>> mount_nfs bombs out with the following error when it attempts to >>>> mount it. >>>> >>>> mount_nfs: >>>> nyisilon2-13.grp2:/ifs/clients/www/csar884520456/files_cms- >>>> stage-BK/imagefield_default_images: >>>> File name too long >>>> >>>> I traced this down to a check in mount_nfs.c . This is about line >>>> 560 >>>> in the 7-STABLE version and 734 in the 9-STABLE version >>>> >>>> >>>> /* >>>> * If there has been a trailing slash at mounttime it seems >>>> * that some mountd implementations fail to remove the >>>> mount >>>> * entries from their mountlist while unmounting. >>>> */ >>>> for (speclen = strlen(spec); >>>> speclen > 1 && spec[speclen - 1] == '/'; >>>> speclen--) >>>> spec[speclen - 1] = '\0'; >>>> if (strlen(hostp) + strlen(spec) + 1 > MNAMELEN) { >>>> warnx("%s:%s: %s", hostp, spec, >>>> strerror(ENAMETOOLONG)); >>>> return (0); >>>> } >>>> >>>> Does any one know why the check for hostp + spec +1 to be less then >>>> MNAMELEN is there for ? >>>> >>>> I removed the check on my 9-STABLE box and it mounts the long >>>> mounts fine >>>> >>>> I submitted a pr for this its kern/167105 >>>> http://www.freebsd.org/cgi/query-pr.cgi?pr=167105 as there is no >>>> mention of this in the man page and I cant find any reason for the >>>> check at all. >>>> >>>> >>>> -- >>>> mark saad | nones...@longcount.org >>>> _______________________________________________ >>>> freebsd-hackers@freebsd.org mailing list >>>> http://lists.freebsd.org/mailman/listinfo/freebsd-hackers >>>> To unsubscribe, send any mail to "freebsd-hackers- >>>> unsubscr...@freebsd.org" >> >> >> >> -- >> mark saad | nones...@longcount.org >> _______________________________________________ >> freebsd-hackers@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-hackers >> To unsubscribe, send any mail to >> "freebsd-hackers-unsubscr...@freebsd.org" _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
