Newsgroups: comp.unix.questions Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!caen!ox.com!math.fu-berlin.de!unidui!veit From: veit@du9ds3.uni-duisburg.de (Holger Veit) Subject: Re: mkdir has stopped working - SCO Xenix Message-ID: Sender: @unidui.uni-duisburg.de Organization: Rechenzentrum Uni-Duisburg References: <1991Apr10.090338.4967@nodecg.ncc.telecomwa.oz.au> <15884@smoke.brl.mil> Date: 18 Apr 91 14:56:46 GMT Lines: 32 In <15884@smoke.brl.mil> gwyn@smoke.brl.mil (Doug Gwyn) writes: >In article <1991Apr10.090338.4967@nodecg.ncc.telecomwa.oz.au> baker@nodecg.ncc.telecomwa.oz.au (mark baker 4206813) writes: >>One of my 386 machines running Xenix 2.3.2 has suddenly refused to let >>any user, including root, from making a directory. >On many UNIX implementations, presumably including yours, >"mkdir" must be installed set-UID 0 in order to work. >I would guess that somebody changed the owners of the system utilities, >or their protection modes, or something like that. I also first guessed that. Mkdir on Sys5 systems depends on the mknod(2) system call which is executable only by root. Mknod allocates a new Inode, which is then linked into the tree, the directory file is then filled with the '.' and '..' entries. Mknod requires root-only execution because you can easily destroy file system consistency with wrong usage or faults. (the root always knows what s/he does :-))))) But Mark Baker said above, that even root cannot make a directory. So, setuid 0 for mkdir is obviously not the problem. I think the effect can be simulated by patching the /etc/passwd root entry to another UID than 0, which would be a very ugly thing if it happened... :-) Hope this helps. Holger -- | | / Holger Veit | INTERNET: veit@du9ds3.uni-duisburg.de |__| / University of Duisburg | BITNET: veit%du9ds3.uni-duisburg.de@UNIDO | | / Fac. of Electr. Eng. | UUCP: ...!uunet!unido!unidui!hl351ge | |/ Dept. f. Dataprocessing |