> Richard L. Hamilton writes: > > pro: not only backups, but bulk file indexers, and > perhaps similar as yet > > unidentified services, might have legitimate use > for keeping atime > > unaltered while reading the files, both for > performance, and because their > > accessing of all files e.g. under a user's home > directory actually _loses_ > > useful information (what good does it do to know > that all the files one > > of these utilities read were read within a few > minutes of one another, > > compared with the utility of knowing the last times > the user more explicitly > > accessed some of their files?). And one view of > least privilege says that > > I'd think that such a utility could cache the lstat() > values and use > those to determine whether it needs to look at the > file at all. > > That'd produce a one-time 'hit' where the first > invocation of this > indexer may cause a read everywhere, but then not > otherwise. > (Besides, given the complexity of a "good" file > indexer, it seems to > me unlikely that the program would be able to make > good use of it. > I'd expect such a thing to have plug-in utilities for > identifying and > generating suitable icons for "foreign" files, and > with that, there > goes your no-atime-change rule.) > > Encouraging the use of this flag outside of some very > narrow > constructs seems like a mistake to me, especially > when there are at > least plausible (and portable) design alternatives. > > > The only things I can see against introducing a new > privilege are: > > * additional complexity > > Yep. That looks like an important one to me. Having > a profusion of > privileges can make the system harder to understand > ... which may well > make it less secure, not more so. > > In this case, it seems like we're having a hard time > assessing whether > this is something that an ordinary user ought to be > able to do. What > hope does an administrator, who certainly understands > his requirements > and users but does not normally get involved in > making OS design > decisions, have in evaluating it?
Either they're not tightly bound by site policy and have to evaluate things all the time (qualified or not), or they are bound, and have to defer to some site authority to evaluate. As an administrator who has been in both situations, as long as the default behavior didn't open things up, I'd favor the flexibility to permit any additional functionality that might be beneficial in the smallest increments possible, which should have the greatest possibility of balancing all concerns. What I'm proposing, while it has _some_ implications (which is why I think it should be controlled), is arguably less prone to serious errors of policy than say PRIV_CHOWN_SELF (which used to be tunable only system-wide via /etc/system). This message posted from opensolaris.org _______________________________________________ opensolaris-code mailing list [email protected] http://mail.opensolaris.org/mailman/listinfo/opensolaris-code
