Re: New Security Features, Please Comment

Alan Cox
2008-12-04T00:13:44Z

> Well, in this particular case, and with this API, perhaps not.

ptrace, patching your own binary, kill etc.

> It would be great if you could say 'limit setuid() to saved-uid + uids
> 1000-2000' or something like that.

For the fsuid

> If then the userlevel NFS server gets owned you can at least be sure
> none of the files in /bin have been modified ..

The userland nfsd uses fsuid.. thats important. Acting on behalf of
another user for file purposes does make sense. I can see a
"setfsuidlist()" call making sense too, but uid/euid/saved uid don't make
sense in this context.

Alan