Bash-4.2 Official Patch 43

[Chet Ramey]

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

Bash-Release:   4.2
Patch-ID:       bash42-043

Bug-Reported-by:        konsolebox <konsolebox@gmail.com>
Bug-Reference-ID:       
<CAJnmqwZuGKLgMsMwxRK4LL+2NN+HgvmKzrnode99QBGrcgX1Lw@mail.gmail.com>
Bug-Reference-URL:      
http://lists.gnu.org/archive/html/bug-bash/2013-01/msg00138.html

Bug-Description:

When SIGCHLD is trapped, and a SIGCHLD trap handler runs when a pending
`read -t' invocation times out and generates SIGALRM, bash can crash with
a segmentation fault.

Patch (apply with `patch -p0'):

*** ../bash-4.2-patched/builtins/read.def       2012-10-31 21:22:51.000517000 
-0400
--- builtins/read.def   2013-01-25 10:28:16.000038000 -0500
***************
*** 386,393 ****
          /* Tricky.  The top of the unwind-protect stack is the free of
             input_string.  We want to run all the rest and use input_string,
!            so we have to remove it from the stack. */
!         remove_unwind_protect ();
!         run_unwind_frame ("read_builtin");
          input_string[i] = '\0';       /* make sure it's terminated */
          retval = 128+SIGALRM;
          goto assign_vars;
--- 386,403 ----
          /* Tricky.  The top of the unwind-protect stack is the free of
             input_string.  We want to run all the rest and use input_string,
!            so we have to save input_string temporarily, run the unwind-
!            protects, then restore input_string so we can use it later. */
! 
          input_string[i] = '\0';       /* make sure it's terminated */
+         if (i == 0)
+           {
+             t = (char *)xmalloc (1);
+             t[0] = 0;
+           }
+         else
+           t = savestring (input_string);
+ 
+         run_unwind_frame ("read_builtin");
+         input_string = t;
          retval = 128+SIGALRM;
          goto assign_vars;

*** ../bash-4.2-patched/patchlevel.h    Sat Jun 12 20:14:48 2010
--- patchlevel.h        Thu Feb 24 21:41:34 2011
***************
*** 26,30 ****
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 42
  
  #endif /* _PATCHLEVEL_H_ */
--- 26,30 ----
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 43
  
  #endif /* _PATCHLEVEL_H_ */

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