Commit f156ff0c authored by Guido van Rossum's avatar Guido van Rossum

Trent Mick:

Various small fixes to the builtin module to ensure no buffer
overflows.

- chunk #1:
Proper casting to ensure no truncation, and hence no surprises, in the
comparison.

- chunk #2:
The id() function guarantees a unique return value for different
objects.  It does this by returning the pointer to the object. By
returning a PyInt, on Win64 (sizeof(long) < sizeof(void*)) the pointer
is truncated and the guarantee may be proven false. The appropriate
return function is PyLong_FromVoidPtr, this returns a PyLong if that
is necessary to return the pointer without truncation.

[GvR: note that this means that id() can now return a long on Win32
platforms.  This *might* break some code...]

- chunk #3:
Ensure no overflow in raw_input(). Granted the user would have to pass
in >2GB of data but it *is* a possible buffer overflow condition.
parent 935eb7a3
......@@ -832,7 +832,7 @@ builtin_eval(self, args)
return NULL;
}
str = PyString_AsString(cmd);
if ((int)strlen(str) != PyString_Size(cmd)) {
if (strlen(str) != (size_t)PyString_Size(cmd)) {
PyErr_SetString(PyExc_ValueError,
"embedded '\\0' in string arg");
return NULL;
......@@ -985,7 +985,7 @@ builtin_id(self, args)
if (!PyArg_ParseTuple(args, "O:id", &v))
return NULL;
return PyInt_FromLong((long)v);
return PyLong_FromVoidPtr(v);
}
static char id_doc[] =
......@@ -1873,7 +1873,14 @@ builtin_raw_input(self, args)
result = NULL;
}
else { /* strip trailing '\n' */
result = PyString_FromStringAndSize(s, strlen(s)-1);
size_t len = strlen(s);
if (len > INT_MAX) {
PyErr_SetString(PyExc_OverflowError, "input too long");
result = NULL;
}
else {
result = PyString_FromStringAndSize(s, (int)(len-1));
}
}
PyMem_FREE(s);
return result;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment