Make asn1 fuzzer more reproducible

Reviewed-by: Rich Salz <rsalz@openssl.org>
GH: #2041

diff --git a/fuzz/asn1.c b/fuzz/asn1.c
index f7b5571d4f7d2d3e21352232b2dc32332c38fe20..f29fde5d4de6c31e5616def766c54a4e8351a1d3 100644 (file)
--- a/fuzz/asn1.c
+++ b/fuzz/asn1.c
@@ -27,6 +27,7 @@
 #include <openssl/ts.h>
 #include <openssl/x509v3.h>
 #include <openssl/cms.h>
+#include <openssl/err.h>
 #include "fuzzer.h"
 
 static ASN1_ITEM_EXP *item_type[] = {
@@ -183,8 +184,21 @@ static ASN1_ITEM_EXP *item_type[] = {
     NULL
 };
 
+static ASN1_PCTX *pctx;
+
 int FuzzerInitialize(int *argc, char ***argv)
 {
+    pctx = ASN1_PCTX_new();
+    ASN1_PCTX_set_flags(pctx, ASN1_PCTX_FLAGS_SHOW_ABSENT |
+        ASN1_PCTX_FLAGS_SHOW_SEQUENCE | ASN1_PCTX_FLAGS_SHOW_SSOF |
+        ASN1_PCTX_FLAGS_SHOW_TYPE | ASN1_PCTX_FLAGS_SHOW_FIELD_STRUCT_NAME);
+    ASN1_PCTX_set_str_flags(pctx, ASN1_STRFLGS_UTF8_CONVERT |
+        ASN1_STRFLGS_SHOW_TYPE | ASN1_STRFLGS_DUMP_ALL);
+
+    OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
+    ERR_get_state();
+    CRYPTO_free_ex_index(0, -1);
+
     return 1;
 }
 
@@ -192,13 +206,6 @@ int FuzzerTestOneInput(const uint8_t *buf, size_t len)
 {
     int n;
 
-    ASN1_PCTX *pctx = ASN1_PCTX_new();
-
-    ASN1_PCTX_set_flags(pctx, ASN1_PCTX_FLAGS_SHOW_ABSENT |
-        ASN1_PCTX_FLAGS_SHOW_SEQUENCE | ASN1_PCTX_FLAGS_SHOW_SSOF |
-        ASN1_PCTX_FLAGS_SHOW_TYPE | ASN1_PCTX_FLAGS_SHOW_FIELD_STRUCT_NAME);
-    ASN1_PCTX_set_str_flags(pctx, ASN1_STRFLGS_UTF8_CONVERT |
-        ASN1_STRFLGS_SHOW_TYPE | ASN1_STRFLGS_DUMP_ALL);
 
     for (n = 0; item_type[n] != NULL; ++n) {
         const uint8_t *b = buf;
@@ -218,11 +225,12 @@ int FuzzerTestOneInput(const uint8_t *buf, size_t len)
         }
     }
 
-    ASN1_PCTX_free(pctx);
+    ERR_clear_error();
 
     return 0;
 }
 
 void FuzzerCleanup(void)
 {
+    ASN1_PCTX_free(pctx);
 }