Re: Proposal "LUID"

On 14 Apr, Linda Walsh wrote:
+-----
|  "Albert D. Cahalan" wrote:
|  > So you only need one system call for this. No CAP_* bit required.
|  > 
|  > int sysluid(int arg){
|  >   int old = current->luid;
|  >   if(old) return old;
|  >   current->luid = arg;
|  >   return arg;
|  > }
|  > 
|  > If login fails to set LUID then, yes, normal users can mess with it.
|  > This is OK because your system wasn't using it anyway.
|  ---
|  	I like it, unfortunately it won't do everything I need.  1) init should start up
|  with LUID==-1 (it's not a valid login ID).  2)  Account 0 should be audited when
+--->8

That's my fault, I characterized luid 0 as special when it's actually
-1.  (In my defense, I tend to think in terms of root not being allowed
to log in to secure systems so luid 0 should never occur.)

Make it "if(old!=-1)" and you get the correct behavior.

-- 
brandon s. allbery	   os/2,linux,solaris,perl	[e-mail]
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carnegie mellon / electrical and computer engineering			kf8nh
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