Fix possible double close and use of unopened socket

HISTORY.rst

@@ -19,6 +19,7 @@ Bug tracker at https://github.com/giampaolo/psutil/issues
 - #797: [Linux] net_if_stats() may raise OSError for certain NIC cards.
 - #813: Process.as_dict() should ignore extraneous attribute names which gets
   attached to the Process instance.
+- #825: Fix possible double close and use of unopened socket 
 
 
 4.1.0 - 2016-03-12

psutil/_psutil_linux.c

@@ -404,7 +404,7 @@ psutil_proc_cpu_affinity_set(PyObject *self, PyObject *args) {
 #else
         long value = PyInt_AsLong(item);
 #endif
-        if (value == -1 && PyErr_Occurred())
+        if (value == -1 || PyErr_Occurred())
             goto error;
         CPU_SET(value, &cpu_set);
     }
@@ -538,17 +538,17 @@ psutil_net_if_stats(PyObject* self, PyObject* args) {
         }
     }
 
-    close(sock);
     py_retlist = Py_BuildValue("[Oiii]", py_is_up, duplex, speed, mtu);
     if (!py_retlist)
         goto error;
+    close(sock);
     Py_DECREF(py_is_up);
     return py_retlist;
 
 error:
-    Py_XDECREF(py_is_up);
-    if (sock != 0)
+    if (sock != -1)
         close(sock);
+    Py_XDECREF(py_is_up);
     PyErr_SetFromErrno(PyExc_OSError);
     return NULL;
 }

psutil/arch/bsd/freebsd.c

@@ -971,7 +971,7 @@ psutil_proc_cpu_affinity_set(PyObject *self, PyObject *args) {
 #else
         long value = PyInt_AsLong(item);
 #endif
-        if (value == -1 && PyErr_Occurred())
+        if (value == -1 || PyErr_Occurred())
             goto error;
         CPU_SET(value, &cpu_set);
     }