crypto: fix assertion caused by unsupported ext

`X509V3_EXT_print` can return value different from `1` if the X509
extension does not support printing to a buffer. Instead of failing with
an unrecoverable assertion - replace the relevant value in the hashmap
with a JS null value.

Fixes: https://hackerone.com/reports/746733

PR-URL: https://github.com/nodejs-private/node-private/pull/175
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Shelley Vohr <codebytere@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Beth Griggs <Bethany.Griggs@uk.ibm.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/src/node_crypto.cc b/src/node_crypto.cc
index 459f5479ac4..92760fb8c85 100644
--- a/src/node_crypto.cc
+++ b/src/node_crypto.cc
@@ -1995,8 +1995,11 @@ static Local<Object> X509ToObject(Environment* env, X509* cert) {
     X509_EXTENSION* ext = X509_get_ext(cert, index);
     CHECK_NOT_NULL(ext);
 
-    if (!SafeX509ExtPrint(bio.get(), ext)) {
-      CHECK_EQ(1, X509V3_EXT_print(bio.get(), ext, 0, 0));
+    if (!SafeX509ExtPrint(bio.get(), ext) &&
+        X509V3_EXT_print(bio.get(), ext, 0, 0) != 1) {
+      info->Set(context, keys[i], Null(env->isolate())).Check();
+      USE(BIO_reset(bio.get()));
+      continue;
     }
 
     BIO_get_mem_ptr(bio.get(), &mem);