Fix some missing inits

(Imported from upstream's f792c663048f19347a1bb72125e535e4fb2ecf39.)

Change-Id: If9bbb10de3ea858076bd9587d21ec331e837dd53
Reviewed-on: https://boringssl-review.googlesource.com/8171
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>

crypto/asn1/a_strnid.c

diff --git a/crypto/asn1/a_strnid.c b/crypto/asn1/a_strnid.c
index ba1224e..c558bce 100644
--- a/crypto/asn1/a_strnid.c
+++ b/crypto/asn1/a_strnid.c
@@ -247,6 +247,7 @@
         }
         tmp->flags = flags | STABLE_FLAGS_MALLOC;
         tmp->nid = nid;
+        tmp->minsize = tmp->maxsize = -1;
         new_nid = 1;
     } else
         tmp->flags = (tmp->flags & STABLE_FLAGS_MALLOC) | flags;

crypto/asn1/bio_asn1.c

diff --git a/crypto/asn1/bio_asn1.c b/crypto/asn1/bio_asn1.c
index 03cc9a6..45ad7e5 100644
--- a/crypto/asn1/bio_asn1.c
+++ b/crypto/asn1/bio_asn1.c
@@ -165,10 +165,12 @@
     ctx->copylen = 0;
     ctx->asn1_class = V_ASN1_UNIVERSAL;
     ctx->asn1_tag = V_ASN1_OCTET_STRING;
-    ctx->ex_buf = 0;
-    ctx->ex_pos = 0;
+    ctx->ex_buf = NULL;
     ctx->ex_len = 0;
+    ctx->ex_pos = 0;
     ctx->state = ASN1_STATE_START;
+    ctx->prefix = ctx->prefix_free = ctx->suffix = ctx->suffix_free = NULL;
+    ctx->ex_arg = NULL;
     return 1;
 }
 

crypto/asn1/bio_ndef.c

diff --git a/crypto/asn1/bio_ndef.c b/crypto/asn1/bio_ndef.c
index 81a8aa7..488457b 100644
--- a/crypto/asn1/bio_ndef.c
+++ b/crypto/asn1/bio_ndef.c
@@ -139,6 +139,7 @@
     ndef_aux->ndef_bio = sarg.ndef_bio;
     ndef_aux->boundary = sarg.boundary;
     ndef_aux->out = out;
+    ndef_aux->derbuf = NULL;
 
     BIO_ctrl(asn_bio, BIO_C_SET_EX_ARG, 0, ndef_aux);