Bash-4.3 Official Patch 48

[Chet Ramey]

                             BASH PATCH REPORT
                             =================

Bash-Release:   4.3
Patch-ID:       bash43-048

Bug-Reported-by:        up201407890@alunos.dcc.fc.up.pt
Bug-Reference-ID:       
<20151210201649.126444eionzfsam8@webmail.alunos.dcc.fc.up.pt>
Bug-Reference-URL:      
http://lists.gnu.org/archive/html/bug-bash/2015-12/msg00054.html

Bug-Description:

If a malicious user can inject a value of $SHELLOPTS containing `xtrace'
and a value for $PS4 that includes a command substitution into a shell
running as root, bash will expand the command substitution as part of
expanding $PS4 when it executes a traced command.

Patch (apply with `patch -p0'):

*** ../bash-4.3-patched/variables.c     2015-11-26 12:31:21.000000000 -0500
--- variables.c 2015-12-23 10:19:01.000000000 -0500
***************
*** 496,500 ****
        set_if_not ("PS2", secondary_prompt);
      }
!   set_if_not ("PS4", "+ ");
  
    /* Don't allow IFS to be imported from the environment. */
--- 496,504 ----
        set_if_not ("PS2", secondary_prompt);
      }
! 
!   if (current_user.euid == 0)
!     bind_variable ("PS4", "+ ", 0);
!   else
!     set_if_not ("PS4", "+ ");
  
    /* Don't allow IFS to be imported from the environment. */

*** ../bash-4.3/patchlevel.h    2012-12-29 10:47:57.000000000 -0500
--- patchlevel.h        2014-03-20 20:01:28.000000000 -0400
***************
*** 26,30 ****
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 47
  
  #endif /* _PATCHLEVEL_H_ */
--- 26,30 ----
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 48
  
  #endif /* _PATCHLEVEL_H_ */

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/