Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!gatech!uflorida!haven!adm!xadmx!niuvax!niucs1!rickert@local.mcs.anl.gov From: niuvax!niucs1!rickert@local.mcs.anl.gov (Neil Rickert) Newsgroups: comp.unix.wizards Subject: Re: Mounting floppies Message-ID: <17711@adm.BRL.MIL> Date: 5 Dec 88 16:54:52 GMT Sender: news@adm.BRL.MIL Lines: 24 Users should be able to mount floppies. But it would take some internal modifications. What is needed is for the kernel to ignore the suid and sgid mode flags for a disk mounted by other than root. Physically changing all of the flags is just a time waste. The kernel already keeps information in memory about each mounted file system. It needs to keep an additional mode flag for the file system which is automatically ANDed with all file modes from files on that file system, to compute an effective mode. When the file system is mounted by "root" on a directory owned by "root" that additional mode flag would consist of all 1's. In other cases it would turn off at least the suid and sgid bits, possibly also the execute bits. Of course anyone other than root should be permitted to mount only a file system on a device he has suitable access permissions to, and only on a directory he owns. This would prevent mounting a replacment for /etc (or even for /tmp). Once these changes are incorporated into Unix it becomes worth investigating arrangements where a user on a work station can mount his work station file system onto a remote system he is connected to. Neil Rickert, Northern Illinois University.