BASH PATCH REPORT
=================
Bash-Release: 4.2
Patch-ID: bash42-053
Bug-Reported-by: Michal Zalewski <lcamtuf@coredump.cx>
Bug-Reference-ID:
Bug-Reference-URL:
Bug-Description:
A combination of nested command substitutions and function importing from
the environment can cause bash to execute code appearing in the environment
variable value following the function definition.
Patch (apply with `patch -p0'):
*** ../bash-4.2.52/builtins/evalstring.c 2014-09-16 19:35:45.000000000 -0400
--- builtins/evalstring.c 2014-10-04 15:00:26.000000000 -0400
***************
*** 262,271 ****
struct fd_bitmap *bitmap;
! if ((flags & SEVAL_FUNCDEF) && command->type != cm_function_def)
{
! internal_warning ("%s: ignoring function definition attempt", from_file);
! should_jump_to_top_level = 0;
! last_result = last_command_exit_value = EX_BADUSAGE;
! break;
}
--- 262,284 ----
struct fd_bitmap *bitmap;
! if (flags & SEVAL_FUNCDEF)
{
! char *x;
!
! /* If the command parses to something other than a straight
! function definition, or if we have not consumed the entire
! string, or if the parser has transformed the function
! name (as parsing will if it begins or ends with shell
! whitespace, for example), reject the attempt */
! if (command->type != cm_function_def ||
! ((x = parser_remaining_input ()) && *x) ||
! (STREQ (from_file, command->value.Function_def->name->word) == 0))
! {
! internal_warning (_("%s: ignoring function definition attempt"), from_file);
! should_jump_to_top_level = 0;
! last_result = last_command_exit_value = EX_BADUSAGE;
! reset_parser ();
! break;
! }
}
***************
*** 332,336 ****
if (flags & SEVAL_ONECMD)
! break;
}
}
--- 345,352 ----
if (flags & SEVAL_ONECMD)
! {
! reset_parser ();
! break;
! }
}
}
*** ../bash-4.2.52/parse.y 2014-09-30 19:24:19.000000000 -0400
--- parse.y 2014-10-04 15:00:26.000000000 -0400
***************
*** 2436,2439 ****
--- 2436,2449 ----
}
+ char *
+ parser_remaining_input ()
+ {
+ if (shell_input_line == 0)
+ return 0;
+ if (shell_input_line_index < 0 || shell_input_line_index >= shell_input_line_len)
+ return '\0'; /* XXX */
+ return (shell_input_line + shell_input_line_index);
+ }
+
#ifdef INCLUDE_UNUSED
/* Back the input pointer up by one, effectively `ungetting' a character. */
***************
*** 3891,3896 ****
/* reset_parser clears shell_input_line and associated variables */
restore_input_line_state (&ls);
! if (interactive)
! token_to_read = 0;
/* Need to find how many characters parse_and_execute consumed, update
--- 3901,3906 ----
/* reset_parser clears shell_input_line and associated variables */
restore_input_line_state (&ls);
!
! token_to_read = 0;
/* Need to find how many characters parse_and_execute consumed, update
*** ../bash-4.2.52/shell.h 2011-11-21 18:03:32.000000000 -0500
--- shell.h 2014-10-04 15:00:26.000000000 -0400
***************
*** 178,181 ****
--- 178,183 ----
/* Let's try declaring these here. */
+ extern char *parser_remaining_input __P((void));
+
extern sh_parser_state_t *save_parser_state __P((sh_parser_state_t *));
extern void restore_parser_state __P((sh_parser_state_t *));