Avoid an undefined shift in ASN1_ENUMERATED_get().

(same fix as in a_int.c rev 1.34)

Fixes oss-fuzz issue #13809

ok beck, jsing

1 files changed, 9 insertions, 4 deletions

diff --git a/src/lib/libcrypto/asn1/a_enum.c b/src/lib/libcrypto/asn1/a_enum.c
index c7d3a9a0ac..0952e049db 100644
--- a/src/lib/libcrypto/asn1/a_enum.c
+++ b/src/lib/libcrypto/asn1/a_enum.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: a_enum.c,v 1.19 2018/04/25 11:48:21 tb Exp $ */
+/* $OpenBSD: a_enum.c,v 1.20 2019/04/28 05:05:56 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -56,6 +56,7 @@
  * [including the GNU Public Licence.]
  */
 
+#include <limits.h>
 #include <stdio.h>
 
 #include <openssl/asn1.h>
@@ -107,7 +108,7 @@ long
 ASN1_ENUMERATED_get(const ASN1_ENUMERATED *a)
 {
         int neg = 0, i;
-        long r = 0;
+        unsigned long r = 0;
 
         if (a == NULL)
                 return (0L);
@@ -128,9 +129,13 @@ ASN1_ENUMERATED_get(const ASN1_ENUMERATED *a)
                 r <<= 8;
                 r |= (unsigned char)a->data[i];
         }
+
+        if (r > LONG_MAX)
+                return -1;
+
         if (neg)
-                r = -r;
-        return (r);
+                return -(long)r;
+        return (long)r;
 }
 
 ASN1_ENUMERATED *