[RFC] Ada ARI fix for sprintf

Pierre Muller
2009-04-07T08:09:39Z

The reason this is a RFC rather than a RFA
is that I used another function than
the one recommended on ARI page.

Currently AR Index gives 153 failures for "sprint" rule.
sprintf 153 Do not use sprintf, instead use xstrprintf
But they seem to all have local static buffers
whereas xstrprintf allocates memory globally.

I propose to use xsnprintf instead for such case,
which checks for buffer overflow.

If you agree, I will also update the
ARI recommendation.

All comments welcome,

Pierre Muller
Pascal language support maintainer for GDB

2009-04-07 Pierre Muller <muller.u-strasbg.fr²>

ARI fix: sprintf rule.
* ada-exp.y (convert_char_literal): Replace sprintf by xsnprintf.
* ada-lang.c (add_angle_bracket): Ditto.
(ada_decode, find_old_style_renaming_symbol): Ditto.
(ada_to_fixed_type_1, ada_enum_name): Ditto.

Index: ada-exp.y
===================================================================
RCS file: /cvs/src/src/gdb/ada-exp.y,v
retrieving revision 1.36
diff -u -p -r1.36 ada-exp.y
--- ada-exp.y 24 Mar 2009 02:08:23 -0000 1.36
+++ ada-exp.y 7 Apr 2009 08:01:25 -0000
@@ -1452,7 +1452,7 @@ convert_char_literal (struct type *type,

if (type == NULL || TYPE_CODE (type) != TYPE_CODE_ENUM)
return val;
- sprintf (name, "QU%02x", (int) val);
+ xsnprintf (name, sizeof (name), "QU%02x", (int) val);
for (f = 0; f < TYPE_NFIELDS (type); f += 1)
{
if (strcmp (name, TYPE_FIELD_NAME (type, f)) == 0)
Index: ada-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/ada-lang.c,v
retrieving revision 1.205
diff -u -p -r1.205 ada-lang.c
--- ada-lang.c 24 Mar 2009 02:07:06 -0000 1.205
+++ ada-lang.c 7 Apr 2009 08:01:28 -0000
@@ -335,11 +335,13 @@ static char *
add_angle_brackets (const char *str)
{
static char *result = NULL;
+ int result_size;

xfree (result);
- result = (char *) xmalloc ((strlen (str) + 3) * sizeof (char));
+ result_size = (strlen (str) + 3) * sizeof (char);
+ result = (char *) xmalloc (result_size);

- sprintf (result, "<%s>", str);
+ xsnprintf (result, result_size, "<%s>", str);
return result;
}

@@ -1114,7 +1116,7 @@ Suppress:
if (encoded[0] == '<')
strcpy (decoded, encoded);
else
- sprintf (decoded, "<%s>", encoded);
+ xsnprintf (decoded, decoding_buffer_size, "<%s>", encoded);
return decoded;

}
@@ -6609,13 +6611,14 @@ find_old_style_renaming_symbol (const ch
function_name = function_name + 5;

rename = (char *) alloca (rename_len * sizeof (char));
- sprintf (rename, "%s__%s___XR", function_name, name);
+ xsnprintf (rename, rename_len * sizeof (char), "%s__%s___XR",
+ function_name, name);
}
else
{
const int rename_len = strlen (name) + 6;
rename = (char *) alloca (rename_len * sizeof (char));
- sprintf (rename, "%s___XR", name);
+ xsnprintf (rename, rename_len * sizeof (char), "%s___XR", name);
}

return ada_find_any_symbol (rename);
@@ -7308,7 +7311,7 @@ ada_to_fixed_type_1 (struct type *type,
int xvz_found = 0;
LONGEST size;

- sprintf (xvz_name, "%s___XVZ", name);
+ xsnprintf (xvz_name, strlen (name) + 7, "%s___XVZ", name);
size = get_int_var_value (xvz_name, &xvz_found);
if (xvz_found && TYPE_LENGTH (fixed_record_type) != size)
{
@@ -7760,11 +7763,11 @@ ada_enum_name (const char *name)

GROW_VECT (result, result_len, 16);
if (isascii (v) && isprint (v))
- sprintf (result, "'%c'", v);
+ xsnprintf (result, result_len, "'%c'", v);
else if (name[1] == 'U')
- sprintf (result, "[\"%02x\"]", v);
+ xsnprintf (result, result_len, "[\"%02x\"]", v);
else
- sprintf (result, "[\"%04x\"]", v);
+ xsnprintf (result, result_len, "[\"%04x\"]", v);