diff options
Diffstat (limited to 'Python')
| -rw-r--r-- | Python/marshal.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/Python/marshal.c b/Python/marshal.c index 8f8ac36..1ef41b0 100644 --- a/Python/marshal.c +++ b/Python/marshal.c @@ -556,7 +556,7 @@ static PyObject * r_PyLong(RFILE *p) { PyLongObject *ob; - int size, i, j, md; + int size, i, j, md, shorts_in_top_digit; long n; digit d; @@ -569,7 +569,8 @@ r_PyLong(RFILE *p) return NULL; } - size = 1 + (ABS(n)-1) / PyLong_MARSHAL_RATIO; + size = 1 + (ABS(n) - 1) / PyLong_MARSHAL_RATIO; + shorts_in_top_digit = 1 + (ABS(n) - 1) % PyLong_MARSHAL_RATIO; ob = _PyLong_New(size); if (ob == NULL) return NULL; @@ -586,12 +587,21 @@ r_PyLong(RFILE *p) ob->ob_digit[i] = d; } d = 0; - for (j=0; j < (ABS(n)-1)%PyLong_MARSHAL_RATIO + 1; j++) { + for (j=0; j < shorts_in_top_digit; j++) { md = r_short(p); if (md < 0 || md > PyLong_MARSHAL_BASE) goto bad_digit; + /* topmost marshal digit should be nonzero */ + if (md == 0 && j == shorts_in_top_digit - 1) { + Py_DECREF(ob); + PyErr_SetString(PyExc_ValueError, + "bad marshal data (unnormalized long data)"); + return NULL; + } d += (digit)md << j*PyLong_MARSHAL_SHIFT; } + /* top digit should be nonzero, else the resulting PyLong won't be + normalized */ ob->ob_digit[size-1] = d; return (PyObject *)ob; bad_digit: |