>From newsserv!kralizec.zeta.org.au!bde Sat Aug 20 01:50:59 1994
From: Bruce Evans <newsserv!kralizec.zeta.org.au!bde>
Newsgroups: stark.freebsd-bugs
Subject: Re:  uucp command fails with permission problems
Date: Mon, 20 Jun 1994 15:13:31 +1000
Organization: Gene Stark's home system
Distribution: stark
NNTP-Posting-Host: home.stark.cs.sunysb.edu
To: FreeBSD-bugfiler@freefall.cdrom.com, gordon@sneaky.lonestar.org
Precedence: bulk

>	The problem stems from the change the setreuid().  It
>	doesn't change the real uid any more, so uucp changes ids
>	back to the wrong id after opening the input file and 
>	then tries to open a file in the spool directory with
>	the invoking user's permissions.
>
>	The promised POSIX saved-setuid features don't work either,

I fixed setuid() and setgid() to support saved ids.  This fixes
uucp (when it is configured with HAVE_BROKEN_SETREUID=1 and
HAVE_SAVED_SETUID=1).  I don't know if the change is really safe.

Bruce

*** sys1/kern/kern_prot.c	Wed May  4 17:54:23 1994
--- src/sys/kern/kern_prot.c	Sun Jun 12 06:47:11 1994
***************
*** 270,274 ****
  
  	uid = uap->uid;
! 	if (uid != pc->p_ruid &&
  	    (error = suser(pc->pc_ucred, &p->p_acflag)))
  		return (error);
--- 270,274 ----
  
  	uid = uap->uid;
! 	if (uid != pc->p_ruid && uid != pc->p_svuid &&
  	    (error = suser(pc->pc_ucred, &p->p_acflag)))
  		return (error);
***************
*** 277,284 ****
  	 * not see our changes.
  	 */
  	pc->pc_ucred = crcopy(pc->pc_ucred);
  	pc->pc_ucred->cr_uid = uid;
- 	pc->p_ruid = uid;
- 	pc->p_svuid = uid;
  	p->p_flag |= SUGID;
  	return (0);
--- 277,286 ----
  	 * not see our changes.
  	 */
+ 	if (pc->pc_ucred->cr_uid == 0) {
+ 		pc->p_ruid = uid;
+ 		pc->p_svuid = uid;
+ 	}
  	pc->pc_ucred = crcopy(pc->pc_ucred);
  	pc->pc_ucred->cr_uid = uid;
  	p->p_flag |= SUGID;
  	return (0);
***************
*** 330,339 ****
  
  	gid = uap->gid;
! 	if (gid != pc->p_rgid && (error = suser(pc->pc_ucred, &p->p_acflag)))
  		return (error);
  	pc->pc_ucred = crcopy(pc->pc_ucred);
  	pc->pc_ucred->cr_groups[0] = gid;
! 	pc->p_rgid = gid;
! 	pc->p_svgid = gid;
  	p->p_flag |= SUGID;
  	return (0);
--- 332,344 ----
  
  	gid = uap->gid;
! 	if (gid != pc->p_rgid && gid != pc->p_svgid &&
! 	    (error = suser(pc->pc_ucred, &p->p_acflag)))
  		return (error);
  	pc->pc_ucred = crcopy(pc->pc_ucred);
  	pc->pc_ucred->cr_groups[0] = gid;
! 	if (pc->pc_ucred->cr_uid == 0) {
! 		pc->p_rgid = gid;
! 		pc->p_svgid = gid;
! 	}
  	p->p_flag |= SUGID;
  	return (0);