binutils-gdb/gdb/ada-lang.h
Joel Brobecker c1b5a1a6e7 Internal error trying to print uninitialized string.
Trying to print the value of a string whose size is not known at
compile-time before it gets assigned a value can lead to the following
internal error:

    (gdb) p my_str
    $1 =
    /[...]/utils.c:1089: internal-error: virtual memory exhausted.

What happens is that my_str is described as a reference to an array
type whose bounds are dynamic. During the read of that variable's
value (in default_read_var_value), we end up resolving dynamic types
which, for reference types, makes us also resolve the target of that
reference type. This means we resolve our variable to a reference
to an array whose bounds are undefined, and unfortunately very far
appart.

So, when we pass that value to ada-valprint, and in particular to
da_val_print_ref, we eventually try to allocate too large of a buffer
corresponding to the (bogus) size of our array, hence the internal
error.

This patch fixes the problem by adding a size_check before trying
to print the dereferenced value. To perform this check, a function
that was previously specific to ada-lang.c (check_size) gets
exported, and renamed to something less prone to name collisions
(ada_ensure_varsize_limit).

gdb/ChangeLog:

        * ada-lang.h (ada_ensure_varsize_limit): Declare.
        * ada-lang.c (check_size): Remove advance declaration.
        (ada_ensure_varsize_limit): Renames check_size.
        Replace calls to check_size by calls to ada_ensure_varsize_limit
        throughout.
        * ada-valprint.c (ada_val_print_ref): Add call to
        ada_ensure_varsize_limit.  Add comment explaining why.

gdb/testsuite/ChangeLog:

        * gdb.ada/str_uninit: New testcase.
2014-12-13 11:00:24 -05:00

422 lines
13 KiB
C

/* Ada language support definitions for GDB, the GNU debugger.
Copyright (C) 1992-2014 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#if !defined (ADA_LANG_H)
#define ADA_LANG_H 1
struct frame_info;
struct inferior;
struct type_print_options;
struct parser_state;
#include "value.h"
#include "gdbtypes.h"
#include "breakpoint.h"
#include "vec.h"
/* Names of specific files known to be part of the runtime
system and that might consider (confusing) debugging information.
Each name (a basic regular expression string) is followed by a
comma. FIXME: Should be part of a configuration file. */
#if defined (__linux__)
#define ADA_KNOWN_RUNTIME_FILE_NAME_PATTERNS \
"^[agis]-.*\\.ad[bs]$", \
"/lib.*/libpthread\\.so[.0-9]*$", "/lib.*/libpthread\\.a$", \
"/lib.*/libc\\.so[.0-9]*$", "/lib.*/libc\\.a$",
#endif
#if !defined (ADA_KNOWN_RUNTIME_FILE_NAME_PATTERNS)
#define ADA_KNOWN_RUNTIME_FILE_NAME_PATTERNS \
"^unwind-seh.c$", \
"^[agis]-.*\\.ad[bs]$",
#endif
/* Names of compiler-generated auxiliary functions probably of no
interest to users. Each name (a basic regular expression string)
is followed by a comma. */
#define ADA_KNOWN_AUXILIARY_FUNCTION_NAME_PATTERNS \
"___clean[.$a-zA-Z0-9_]*$", \
"___finalizer[.$a-zA-Z0-9_]*$",
/* The maximum number of frame levels searched for non-local,
* non-global symbols. This limit exists as a precaution to prevent
* infinite search loops when the stack is screwed up. */
#define MAX_ENCLOSING_FRAME_LEVELS 7
/* Maximum number of steps followed in looking for the ultimate
referent of a renaming. This prevents certain infinite loops that
can otherwise result. */
#define MAX_RENAMING_CHAIN_LENGTH 10
struct block;
/* Corresponding encoded/decoded names and opcodes for Ada user-definable
operators. */
struct ada_opname_map
{
const char *encoded;
const char *decoded;
enum exp_opcode op;
};
/* Table of Ada operators in encoded and decoded forms. */
/* Defined in ada-lang.c */
extern const struct ada_opname_map ada_opname_table[];
/* A tuple representing one instance of a symbol-lookup operation. */
struct ada_symbol_info
{
/* The symbol that was found. */
struct symbol *sym;
/* The block where the symbol was found. */
const struct block *block;
};
/* Denotes a type of renaming symbol (see ada_parse_renaming). */
enum ada_renaming_category
{
/* Indicates a symbol that does not encode a renaming. */
ADA_NOT_RENAMING,
/* For symbols declared
Foo : TYPE renamed OBJECT; */
ADA_OBJECT_RENAMING,
/* For symbols declared
Foo : exception renames EXCEPTION; */
ADA_EXCEPTION_RENAMING,
/* For packages declared
package Foo renames PACKAGE; */
ADA_PACKAGE_RENAMING,
/* For subprograms declared
SUBPROGRAM_SPEC renames SUBPROGRAM;
(Currently not used). */
ADA_SUBPROGRAM_RENAMING
};
/* The different types of catchpoints that we introduced for catching
Ada exceptions. */
enum ada_exception_catchpoint_kind
{
ada_catch_exception,
ada_catch_exception_unhandled,
ada_catch_assert
};
/* Ada task structures. */
struct ada_task_info
{
/* The PTID of the thread that this task runs on. This ptid is computed
in a target-dependent way from the associated Task Control Block. */
ptid_t ptid;
/* The ID of the task. */
CORE_ADDR task_id;
/* The name of the task. */
char name[257];
/* The current state of the task. */
int state;
/* The priority associated to the task. */
int priority;
/* If non-zero, the task ID of the parent task. */
CORE_ADDR parent;
/* If the task is waiting on a task entry, this field contains
the ID of the other task. Zero otherwise. */
CORE_ADDR called_task;
/* If the task is accepting a rendezvous with another task, this field
contains the ID of the calling task. Zero otherwise. */
CORE_ADDR caller_task;
};
/* Assuming V points to an array of S objects, make sure that it contains at
least M objects, updating V and S as necessary. */
#define GROW_VECT(v, s, m) \
if ((s) < (m)) (v) = grow_vect (v, &(s), m, sizeof *(v));
extern void *grow_vect (void *, size_t *, size_t, int);
extern void ada_ensure_varsize_limit (const struct type *type);
extern int ada_get_field_index (const struct type *type,
const char *field_name,
int maybe_missing);
extern int ada_parse (struct parser_state *); /* Defined in ada-exp.y */
extern void ada_error (char *); /* Defined in ada-exp.y */
/* Defined in ada-typeprint.c */
extern void ada_print_type (struct type *, const char *, struct ui_file *, int,
int, const struct type_print_options *);
extern void ada_print_typedef (struct type *type, struct symbol *new_symbol,
struct ui_file *stream);
extern void ada_val_print (struct type *, const gdb_byte *, int, CORE_ADDR,
struct ui_file *, int,
const struct value *,
const struct value_print_options *);
extern void ada_value_print (struct value *, struct ui_file *,
const struct value_print_options *);
/* Defined in ada-lang.c */
extern void ada_emit_char (int, struct type *, struct ui_file *, int, int);
extern void ada_printchar (int, struct type *, struct ui_file *);
extern void ada_printstr (struct ui_file *, struct type *, const gdb_byte *,
unsigned int, const char *, int,
const struct value_print_options *);
struct value *ada_convert_actual (struct value *actual,
struct type *formal_type0);
extern struct value *ada_value_subscript (struct value *, int,
struct value **);
extern void ada_fixup_array_indexes_type (struct type *index_desc_type);
extern struct type *ada_array_element_type (struct type *, int);
extern int ada_array_arity (struct type *);
struct type *ada_type_of_array (struct value *, int);
extern struct value *ada_coerce_to_simple_array_ptr (struct value *);
struct value *ada_coerce_to_simple_array (struct value *);
extern int ada_is_simple_array_type (struct type *);
extern int ada_is_array_descriptor_type (struct type *);
extern int ada_is_bogus_array_descriptor (struct type *);
extern LONGEST ada_discrete_type_low_bound (struct type *);
extern LONGEST ada_discrete_type_high_bound (struct type *);
extern struct value *ada_get_decoded_value (struct value *value);
extern struct type *ada_get_decoded_type (struct type *type);
extern const char *ada_decode_symbol (const struct general_symbol_info *);
extern const char *ada_decode (const char*);
extern enum language ada_update_initial_language (enum language);
extern int ada_lookup_symbol_list (const char *, const struct block *,
domain_enum, struct ada_symbol_info**);
extern char *ada_fold_name (const char *);
extern struct symbol *ada_lookup_symbol (const char *, const struct block *,
domain_enum, int *);
extern void ada_lookup_encoded_symbol
(const char *name, const struct block *block, domain_enum namespace,
struct ada_symbol_info *symbol_info);
extern struct bound_minimal_symbol ada_lookup_simple_minsym (const char *);
extern void ada_fill_in_ada_prototype (struct symbol *);
extern int user_select_syms (struct ada_symbol_info *, int, int);
extern int get_selections (int *, int, int, int, char *);
extern int ada_scan_number (const char *, int, LONGEST *, int *);
extern struct type *ada_parent_type (struct type *);
extern int ada_is_ignored_field (struct type *, int);
extern int ada_is_constrained_packed_array_type (struct type *);
extern struct value *ada_value_primitive_packed_val (struct value *,
const gdb_byte *,
long, int, int,
struct type *);
extern struct type *ada_coerce_to_simple_array_type (struct type *);
extern int ada_is_character_type (struct type *);
extern int ada_is_string_type (struct type *);
extern int ada_is_tagged_type (struct type *, int);
extern int ada_is_tag_type (struct type *);
extern struct type *ada_tag_type (struct value *);
extern struct value *ada_value_tag (struct value *);
extern const char *ada_tag_name (struct value *);
extern struct value *ada_tag_value_at_base_address (struct value *obj);
extern int ada_is_parent_field (struct type *, int);
extern int ada_is_wrapper_field (struct type *, int);
extern int ada_is_variant_part (struct type *, int);
extern struct type *ada_variant_discrim_type (struct type *, struct type *);
extern int ada_is_others_clause (struct type *, int);
extern int ada_in_variant (LONGEST, struct type *, int);
extern char *ada_variant_discrim_name (struct type *);
extern struct value *ada_value_struct_elt (struct value *, char *, int);
extern int ada_is_aligner_type (struct type *);
extern struct type *ada_aligned_type (struct type *);
extern const gdb_byte *ada_aligned_value_addr (struct type *,
const gdb_byte *);
extern const char *ada_attribute_name (enum exp_opcode);
extern int ada_is_fixed_point_type (struct type *);
extern int ada_is_system_address_type (struct type *);
extern DOUBLEST ada_delta (struct type *);
extern DOUBLEST ada_fixed_to_float (struct type *, LONGEST);
extern LONGEST ada_float_to_fixed (struct type *, DOUBLEST);
extern struct type *ada_system_address_type (void);
extern int ada_which_variant_applies (struct type *, struct type *,
const gdb_byte *);
extern struct type *ada_to_fixed_type (struct type *, const gdb_byte *,
CORE_ADDR, struct value *,
int check_tag);
extern struct value *ada_to_fixed_value (struct value *val);
extern struct type *ada_template_to_fixed_record_type_1 (struct type *type,
const gdb_byte *valaddr,
CORE_ADDR address,
struct value *dval0,
int keep_dynamic_fields);
extern int ada_name_prefix_len (const char *);
extern const char *ada_type_name (struct type *);
extern struct type *ada_find_parallel_type (struct type *,
const char *suffix);
extern LONGEST get_int_var_value (char *, int *);
extern struct symbol *ada_find_renaming_symbol (struct symbol *name_sym,
const struct block *block);
extern int ada_prefer_type (struct type *, struct type *);
extern struct type *ada_get_base_type (struct type *);
extern struct type *ada_check_typedef (struct type *);
extern char *ada_encode (const char *);
extern const char *ada_enum_name (const char *);
extern int ada_is_modular_type (struct type *);
extern ULONGEST ada_modulus (struct type *);
extern struct value *ada_value_ind (struct value *);
extern void ada_print_scalar (struct type *, LONGEST, struct ui_file *);
extern int ada_is_range_type_name (const char *);
extern enum ada_renaming_category ada_parse_renaming (struct symbol *,
const char **,
int *, const char **);
extern void ada_find_printable_frame (struct frame_info *fi);
extern char *ada_breakpoint_rewrite (char *, int *);
extern char *ada_main_name (void);
extern char *ada_name_for_lookup (const char *name);
extern void create_ada_exception_catchpoint
(struct gdbarch *gdbarch, enum ada_exception_catchpoint_kind ex_kind,
char *excep_string, char *cond_string, int tempflag, int disabled,
int from_tty);
/* Some information about a given Ada exception. */
typedef struct ada_exc_info
{
/* The name of the exception. */
const char *name;
/* The address of the symbol corresponding to that exception. */
CORE_ADDR addr;
} ada_exc_info;
DEF_VEC_O(ada_exc_info);
extern VEC(ada_exc_info) *ada_exceptions_list (const char *regexp);
/* Tasking-related: ada-tasks.c */
extern int valid_task_id (int);
extern int ada_get_task_number (ptid_t);
typedef void (ada_task_list_iterator_ftype) (struct ada_task_info *task);
extern void iterate_over_live_ada_tasks
(ada_task_list_iterator_ftype *iterator);
extern int ada_build_task_list (void);
extern void print_ada_task_info (struct ui_out *uiout,
char *taskno_str,
struct inferior *inf);
#endif