From: Mark Wooding <mdw@distorted.org.uk>
Date: Fri, 18 Oct 2019 21:15:46 +0000 (+0100)
Subject: ec.c (eccurve_pyrichcompare): Check that second operand has correct type.
X-Git-Url: https://git.distorted.org.uk/~mdw/catacomb-python/commitdiff_plain/7f8c2476ae775cfe27be5a216cebb6ad35432185

ec.c (eccurve_pyrichcompare): Check that second operand has correct type.

A segfault waiting to happen, which has been lurking since the
beginning.
---

diff --git a/ec.c b/ec.c
index c8cdebe..0df218b 100644
--- a/ec.c
+++ b/ec.c
@@ -788,7 +788,11 @@ static PyTypeObject ecptcurve_pytype_skel = {
 
 static PyObject *eccurve_pyrichcompare(PyObject *x, PyObject *y, int op)
 {
-  int b = ec_samep(ECCURVE_C(x), ECCURVE_C(y));
+  int b;
+
+  assert(ECCURVE_PYCHECK(x));
+  if (!ECCURVE_PYCHECK(y)) RETURN_NOTIMPL;
+  b = ec_samep(ECCURVE_C(x), ECCURVE_C(y));
   switch (op) {
     case Py_EQ: break;
     case Py_NE: b = !b; break;