On Thu, 13 May 1999 15:02:40 +0100 (BST), Julian Gilbey wrote: >> Glad to hear all of this. I just have one comment: >> >> > - The mktexlsr, mktexdir and mktexupd scripts must not be setuid. >> > If they are, anyone could run them, which is unnecessary. Any >> > extra privileges they require will be gained when they are called >> > from other setuid processes. >> >> It seems to me that *only* these three should be setuid, since only >> these three need elevated privileges. mktextfm, etc. should be >> changed to write the output into a scratch directory, and have >> mktexupd move it into place. >> >> Yes, this does mean anyone can invoke them, but if properly designed >> no damage can be done, and this restricts the scope of the changes and >> the scope of the specially privileged code much better. > >No, absolutely not. If mktexupd is setuid, then anyone can make it do >anything to the ls-R file, I would guess.
Only if mktexupd is misdesigned; it ought to be capable of validating updates. >And having mktex{mf,tfm,pk} >writing to a scratch directory defeats the purpose of making the fonts >directory read only, as anyone could then create a corrupt font file >in the scratch directory and run mktexupd. This is a problem, but isn't there some simple, efficient way to validate font files? zw