Bash-4.1 Official Patch 15

[Chet Ramey]

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

Bash-Release:   4.1
Patch-ID:       bash41-015

Bug-Reported-by:        Florian Weimer <fweimer@redhat.com>
Bug-Reference-ID:
Bug-Reference-URL:

Bug-Description:

There are two local buffer overflows in parse.y that can cause the shell
to dump core when given many here-documents attached to a single command
or many nested loops.

Patch (apply with `patch -p0'):

*** ../bash-4.1.14/parse.y      2014-09-27 12:18:25.000000000 -0400
--- parse.y     2014-09-30 19:36:03.000000000 -0400
***************
*** 168,171 ****
--- 168,174 ----
  static int reserved_word_acceptable __P((int));
  static int yylex __P((void));
+ 
+ static void push_heredoc __P((REDIRECT *));
+ static char *mk_alexpansion __P((char *));
  static int alias_expand_token __P((char *));
  static int time_command_acceptable __P((void));
***************
*** 262,266 ****
  /* Variables to manage the task of reading here documents, because we need to
     defer the reading until after a complete command has been collected. */
! static REDIRECT *redir_stack[10];
  int need_here_doc;
  
--- 265,271 ----
  /* Variables to manage the task of reading here documents, because we need to
     defer the reading until after a complete command has been collected. */
! #define HEREDOC_MAX 16
! 
! static REDIRECT *redir_stack[HEREDOC_MAX];
  int need_here_doc;
  
***************
*** 304,308 ****
     index is decremented after a case, select, or for command is parsed. */
  #define MAX_CASE_NEST 128
! static int word_lineno[MAX_CASE_NEST];
  static int word_top = -1;
  
--- 309,313 ----
     index is decremented after a case, select, or for command is parsed. */
  #define MAX_CASE_NEST 128
! static int word_lineno[MAX_CASE_NEST+1];
  static int word_top = -1;
  
***************
*** 517,521 ****
                          redir.filename = $2;
                          $$ = make_redirection (source, r_reading_until, 
redir, 0);
!                         redir_stack[need_here_doc++] = $$;
                        }
        |       NUMBER LESS_LESS WORD
--- 522,526 ----
                          redir.filename = $2;
                          $$ = make_redirection (source, r_reading_until, 
redir, 0);
!                         push_heredoc ($$);
                        }
        |       NUMBER LESS_LESS WORD
***************
*** 524,528 ****
                          redir.filename = $3;
                          $$ = make_redirection (source, r_reading_until, 
redir, 0);
!                         redir_stack[need_here_doc++] = $$;
                        }
        |       REDIR_WORD LESS_LESS WORD
--- 529,533 ----
                          redir.filename = $3;
                          $$ = make_redirection (source, r_reading_until, 
redir, 0);
!                         push_heredoc ($$);
                        }
        |       REDIR_WORD LESS_LESS WORD
***************
*** 531,535 ****
                          redir.filename = $3;
                          $$ = make_redirection (source, r_reading_until, 
redir, REDIR_VARASSIGN);
!                         redir_stack[need_here_doc++] = $$;
                        }
        |       LESS_LESS_MINUS WORD
--- 536,540 ----
                          redir.filename = $3;
                          $$ = make_redirection (source, r_reading_until, 
redir, REDIR_VARASSIGN);
!                         push_heredoc ($$);
                        }
        |       LESS_LESS_MINUS WORD
***************
*** 538,542 ****
                          redir.filename = $2;
                          $$ = make_redirection (source, 
r_deblank_reading_until, redir, 0);
!                         redir_stack[need_here_doc++] = $$;
                        }
        |       NUMBER LESS_LESS_MINUS WORD
--- 543,547 ----
                          redir.filename = $2;
                          $$ = make_redirection (source, 
r_deblank_reading_until, redir, 0);
!                         push_heredoc ($$);
                        }
        |       NUMBER LESS_LESS_MINUS WORD
***************
*** 545,549 ****
                          redir.filename = $3;
                          $$ = make_redirection (source, 
r_deblank_reading_until, redir, 0);
!                         redir_stack[need_here_doc++] = $$;
                        }
        |       REDIR_WORD  LESS_LESS_MINUS WORD
--- 550,554 ----
                          redir.filename = $3;
                          $$ = make_redirection (source, 
r_deblank_reading_until, redir, 0);
!                         push_heredoc ($$);
                        }
        |       REDIR_WORD  LESS_LESS_MINUS WORD
***************
*** 552,556 ****
                          redir.filename = $3;
                          $$ = make_redirection (source, 
r_deblank_reading_until, redir, REDIR_VARASSIGN);
!                         redir_stack[need_here_doc++] = $$;
                        }
        |       LESS_LESS_LESS WORD
--- 557,561 ----
                          redir.filename = $3;
                          $$ = make_redirection (source, 
r_deblank_reading_until, redir, REDIR_VARASSIGN);
!                         push_heredoc ($$);
                        }
        |       LESS_LESS_LESS WORD
***************
*** 2508,2511 ****
--- 2513,2531 ----
  static int esacs_needed_count;
  
+ static void
+ push_heredoc (r)
+      REDIRECT *r;
+ {
+   if (need_here_doc >= HEREDOC_MAX)
+     {
+       last_command_exit_value = EX_BADUSAGE;
+       need_here_doc = 0;
+       report_syntax_error (_("maximum here-document count exceeded"));
+       reset_parser ();
+       exit_shell (last_command_exit_value);
+     }
+   redir_stack[need_here_doc++] = r;
+ }
+ 
  void
  gather_here_documents ()
*** ../bash-4.1-patched/patchlevel.h    2009-10-01 16:39:22.000000000 -0400
--- patchlevel.h        2010-01-14 09:38:08.000000000 -0500
***************
*** 26,30 ****
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 14
  
  #endif /* _PATCHLEVEL_H_ */
--- 26,30 ----
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 15
  
  #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/