commit 0d7cb5bb291d8645824581ae570a394e3d221e5e
author Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> Thu Sep 12 06:50:46 2019 -0700
committer GitHub <noreply@github.com> Thu Sep 12 06:50:46 2019 -0700
tree 909c0f1fb4bdfa7f8bd47926b4a456c43b97d6ae
parent 2f01cf61874aa42eeb9999e49d51d4881792d9c4

bpo-38132: Check EVP_DigestUpdate for error (GH-16041)

(cherry picked from commit 8c74574e0aaf1a00719fbc9acbdc27a3923520aa)

Co-authored-by: Christian Heimes <christian@python.org>

Modules/_hashopenssl.c

diff --git a/Modules/_hashopenssl.c b/Modules/_hashopenssl.c
index 798317f..bea7e5e 100644
--- a/Modules/_hashopenssl.c
+++ b/Modules/_hashopenssl.c
@@ -96,7 +96,7 @@
     return retval;
 }
 
-static void
+static int
 EVP_hash(EVPobject *self, const void *vp, Py_ssize_t len)
 {
     unsigned int process;
@@ -108,11 +108,12 @@
             process = Py_SAFE_DOWNCAST(len, Py_ssize_t, unsigned int);
         if (!EVP_DigestUpdate(self->ctx, (const void*)cp, process)) {
             _setException(PyExc_ValueError);
-            break;
+            return -1;
         }
         len -= process;
         cp += process;
     }
+    return 0;
 }
 
 /* Internal methods for a hash object */
@@ -243,6 +244,7 @@
 EVP_update(EVPobject *self, PyObject *obj)
 /*[clinic end generated code: output=ec1d55ed2432e966 input=9b30ec848f015501]*/
 {
+    int result;
     Py_buffer view;
 
     GET_BUFFER_VIEW_OR_ERROUT(obj, &view);
@@ -255,14 +257,17 @@
     if (self->lock != NULL) {
         Py_BEGIN_ALLOW_THREADS
         PyThread_acquire_lock(self->lock, 1);
-        EVP_hash(self, view.buf, view.len);
+        result = EVP_hash(self, view.buf, view.len);
         PyThread_release_lock(self->lock);
         Py_END_ALLOW_THREADS
     } else {
-        EVP_hash(self, view.buf, view.len);
+        result = EVP_hash(self, view.buf, view.len);
     }
 
     PyBuffer_Release(&view);
+
+    if (result == -1)
+        return NULL;
     Py_RETURN_NONE;
 }
 
@@ -396,6 +401,7 @@
 EVPnew(const EVP_MD *digest,
        const unsigned char *cp, Py_ssize_t len)
 {
+    int result = 0;
     EVPobject *self;
 
     if (!digest) {
@@ -415,10 +421,14 @@
     if (cp && len) {
         if (len >= HASHLIB_GIL_MINSIZE) {
             Py_BEGIN_ALLOW_THREADS
-            EVP_hash(self, cp, len);
+            result = EVP_hash(self, cp, len);
             Py_END_ALLOW_THREADS
         } else {
-            EVP_hash(self, cp, len);
+            result = EVP_hash(self, cp, len);
+        }
+        if (result == -1) {
+            Py_DECREF(self);
+            return NULL;
         }
     }