Dear Managers,
I received many replies, but the gold star goes to:
"Thomas M. Payerle" <payerle_at_physics.umd.edu>
His message:
Just a wild idea, but could it be something with his trashcan and/or
quota? I don't recall mention of what filesystem you are using.
User obviously can create files (unpacking, 1st compilation) but cannot
remove or write over. You mentioned a trashcan; how is that working?
My comment:
The trashcan is the one implemented by the mktrashcan utility
in the AdvFS utilities. Somehow root had gained ownership of
"nlecren"'s trashcan and a few others, so rm couldn't write any files
there. I quickly made sure everyone owned their trashcans and
modified my "new_account" script to make sure that it checked this.
My student can now delete files normally. I feel stupid; I never
thought to check the trashcans because I never envisioned any way that
the trashcan ownership would change.
Other replies and their suggestions (which might also have been the
problem):
"Skeate, Scott B" <scott.b.skeate_at_lmco.com>
ARENA Vincenzo <Vincenzo.Arena_at_omnitel.it>
Ralph Rodriguez <rrodrigu_at_ssc.wisc.edu>
"Lauzier, Edward" <LauzierE_at_hanscom.af.mil>
Bob Sloane <SLOANE_at_KUHUB.CC.UKANS.EDU>
Roberto Romani <roberto.romani_at_digital.com>
Brenden Phillips <B.C.Phillips_at_massey.ac.nz>
Laurent Deniel <deniel_at_worldnet.fr>
smcgly - Sean McGlynn <SMCGLY_at_acxiom.co.uk>
"Eisenman, Richard" <richarde_at_tricity.wsu.edu>
1. Check file and parent directory permissions. (this was OK)
2. Create a subdirectory (possibly with 755 permissions) and unpack
there. (I never got around to trying this.)
3. Check the user id is unique. (this was OK)
4. Check if the user was using ACLs. (We do allow ACLs, but the user
didn't have one. I had checked this.)
5. If the user's directory is NFS mounted, check the mount point (in
my case it's /usr/users that is the mount point)
6. Check that rm isn't an alias (it wasn't in my case).
Thanks to all of the above!
Original post
-------------
Dear Managers,
A student of mine has a weird problem. I asked the class to
unpack a .tar.gz file I had written and use it in an assignment. The
student unpacked the file but had trouble compiling it because of
"permission denied" errors. Specifically the (GNU C++) compiler
failed while writing the *.o files. The student tried to use rm to
remove them but failed (in fact, the source files couldn't be deleted
either).
The following remedies have been attempted without success:
i) It was verified that ownership, group membership, and permissions
(600 on the source and object files) were correct. A chown and chmod
command was performed by root anyways without any apparent change.
ii) root (successfully) removed the files. The student unpacked the
.tar.gz file again, with the same lack of success.
iii) Compiles were attempted both with direct commands and with
makefiles (both DEC and GNU make).
iv) I tried the same operation from a test account I maintain which
only has general user privileges (the student's account would be in
the same group as the owner of the archive, but otherwise would be set
up in the same way). This account had no difficulty in unpacking the
archive, compiling, removing the files, unpacking again, compiling
again, and removing again.
v) I tried removing the student account and generating a fresh account
with the same user id. The home directory was deleted and a default
home directory created. The student was able to successfully unpack
and compile ONCE, but the second time the permission problems
recurred.
vi) I tried searching for files owned by this user. Nothing outside
his directory, his trashcan, and his pseudo-terminals was found.
vii) I tried generating a new account with a different username and
different userid. Same problem.
I get the feeling this is some kind of bizarre locking problem,
but I'm at a loss to find it.
System: DEC 3000/600 and 300LX, DU v4.0D with patch kit #2, GNU C++
v.2.8.1. C2 security is in use. The .tar.gz file is one I wrote and
it has been in successful use prior to this incident.
Larry
============================================================================
Larry Griffith Dept. of Computer & Info Science
larry_at_cs.wsc.ma.edu Westfield State College
(413) 572-5294 Westfield, MA 01086 USA
PGP public key available at:
http://cs.wsc.ma.edu/dcis/griffith.html
NOTE NEW E-MAIL ADDRESS!!
============================================================================
Received on Tue Sep 29 1998 - 22:03:04 NZST