tip bug fix

Thread View: comp.bugs.2bsd

3 messages

[T] Back to Threads [V] Tree View [G] Group Articles

3 total messages Started by Jack Nelson Tue, 03 May 1988 19:07

#195

Author: Jack Nelson
Date: Tue, 03 May 1988 19:07

50 lines
2076 bytes

Index:	/usr/src/usr.bin/tip/cmds.c  2.10BSD

Description:
	tip(1) will not properly run a shell if the environment
	SHELL is /bin/csh or /bin/tcsh.
Repeat-By:
	Procedure to repeat the problem: try it.  Works ok if SHELL=/bin/sh
	or if .tiprc has a line "SHELL=/bin/sh", but then you get /bin/sh.
Fix:
	Description of how to fix the problem:
	patch cmds.c to use the "-b" option as documented in csh(1) to
	be necessary when you run setuid and try to fork a csh.
	The patch calls sh(1) without that flag, all other with it.  If
	you use some other shell besides csh or tcsh this will not be
	general enough.

UUCP: { akgua | allegra | cmcl2 | idis | ihnp4 | mi-cec | pitt |
	psuvax1 | sun | sunrise | vax135 } ! cadre ! nelslab ! jack
ARPA: jack@cadre.dsl.pittsburgh.edu
John P. Nelson, M.D., 3811 O'Hara St, Pittsburgh, PA 15213, t:412-624-1769
Dept. of Psychiatry, U. of Pittsburgh

Cut:--------------
*** cmds.c.org	Wed Dec 16 16:24:47 1987
--- cmds.c	Fri Mar 25 15:35:15 1988
***************
*** 547,553 ****
  			cp = value(SHELL);
  		else
  			cp++;
! 		execl(value(SHELL), cp, 0);
  		printf("\r\ncan't execl!\r\n");
  		exit(1);
  	}
--- 547,556 ----
  			cp = value(SHELL);
  		else
  			cp++;
! 		if (strcmp(cp,"sh") == 0)
! 			execl(value(SHELL), cp, 0);
! 		else
! 			execl(value(SHELL), cp, "-b", 0);
  		printf("\r\ncan't execl!\r\n");
  		exit(1);
  	}
-- 
John P. Nelson, M.D., 3811 O'Hara St, Pittsburgh, PA 15213, t:412-624-1769 Dept. of Psychiatry, U. of Pittsburgh
UUCP: { akgua | allegra | cmcl2 | idis | ihnp4 | mi-cec | pitt | psuvax1 | sun | sunrise | vax135 } ! cadre ! jack
ARPA: jack@cadre.dsl.pittsburgh.edu

Re: tip bug fix

#197

Author: Ian Donaldson
Date: Sun, 08 May 1988 07:34

21 lines
960 bytes

From article <1160@cadre.dsl.PITTSBURGH.EDU>, by jack@cadre.dsl.PITTSBURGH.EDU (Jack Nelson):
> Index:	/usr/src/usr.bin/tip/cmds.c  2.10BSD
> 
> Description:
> 	tip(1) will not properly run a shell if the environment
> 	SHELL is /bin/csh or /bin/tcsh.
 ...
> Fix:
> 	Description of how to fix the problem:
> 	patch cmds.c to use the "-b" option as documented in csh(1) to
> 	be necessary when you run setuid and try to fork a csh.

No!  That is definitely NOT the fix.  You should instead do a:

	setuid(getuid());
	setgid(getgid());

before you exec the shell!!
(same bug in 4.3bsd tip)

Ian D

Re: tip bug fix

#198

Author: Ian Donaldson
Date: Sun, 08 May 1988 07:44

10 lines
717 bytes

In article <759@yabbie.rmit.oz>, rcodi@yabbie.rmit.oz (Ian Donaldson) writes:
> No!  That is definitely NOT the fix.  You should instead do a:
> 
> 	setuid(getuid());
> 	setgid(getgid());

A temporary workaround for those without source is to make tip a non-s[ug]id
program and make /usr/spool/uucp mode 777 (like Suns do it).  (yuk).

Ian D

Thread Navigation

This is a paginated view of messages in the thread with full content displayed inline.

Messages are displayed in chronological order, with the original post highlighted in green.

Use pagination controls to navigate through all messages in large threads.

Back to All Threads