BASH PATCH REPORT ================= Bash-Release: 4.2 Patch-ID: bash42-053 Bug-Reported-by: Michal Zalewski 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 *)); *** ../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 52 #endif /* _PATCHLEVEL_H_ */ --- 26,30 ---- looks for to find the patch level (for the sccs version string). */ ! #define PATCHLEVEL 53 #endif /* _PATCHLEVEL_H_ */