prevent a crash with openssl asn1parse -genstr FORMAT

aka ASN1_generate_nconf("FORMAT", NULL)

ok krw@ beck@ jsing@

2 files changed, 10 insertions, 2 deletions

diff --git a/src/lib/libcrypto/asn1/asn1_gen.c b/src/lib/libcrypto/asn1/asn1_gen.c
index 97be43a03a..384088308f 100644
--- a/src/lib/libcrypto/asn1/asn1_gen.c
+++ b/src/lib/libcrypto/asn1/asn1_gen.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: asn1_gen.c,v 1.12 2014/07/11 08:44:47 jsing Exp $ */
+/* $OpenBSD: asn1_gen.c,v 1.13 2015/02/12 06:04:24 jsg Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2002.
  */
@@ -348,6 +348,10 @@ asn1_cb(const char *elem, int len, void *bitstr)
                 break;
 
         case ASN1_GEN_FLAG_FORMAT:
+                if (vstart == NULL) {
+                        ASN1err(ASN1_F_ASN1_CB, ASN1_R_ILLEGAL_FORMAT);
+                        return -1;
+                }
                 if (!strncmp(vstart, "ASCII", 5))
                         arg->format = ASN1_GEN_FORMAT_ASCII;
                 else if (!strncmp(vstart, "UTF8", 4))
diff --git a/src/lib/libssl/src/crypto/asn1/asn1_gen.c b/src/lib/libssl/src/crypto/asn1/asn1_gen.c
index 97be43a03a..384088308f 100644
--- a/src/lib/libssl/src/crypto/asn1/asn1_gen.c
+++ b/src/lib/libssl/src/crypto/asn1/asn1_gen.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: asn1_gen.c,v 1.12 2014/07/11 08:44:47 jsing Exp $ */
+/* $OpenBSD: asn1_gen.c,v 1.13 2015/02/12 06:04:24 jsg Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2002.
  */
@@ -348,6 +348,10 @@ asn1_cb(const char *elem, int len, void *bitstr)
                 break;
 
         case ASN1_GEN_FLAG_FORMAT:
+                if (vstart == NULL) {
+                        ASN1err(ASN1_F_ASN1_CB, ASN1_R_ILLEGAL_FORMAT);
+                        return -1;
+                }
                 if (!strncmp(vstart, "ASCII", 5))
                         arg->format = ASN1_GEN_FORMAT_ASCII;
                 else if (!strncmp(vstart, "UTF8", 4))