Free up ADB and CHOICE if already initialised.

CVE-2015-0287

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Emilia Käsper <emilia@openssl.org>

crypto/asn1/tasn_dec.c

@@ -303,9 +303,16 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
    case ASN1_ITYPE_CHOICE:
        if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
            goto auxerr;

        /* Allocate structure */
        if (!*pval && !ASN1_item_ex_new(pval, it)) {
        if (*pval) {
            /* Free up and zero CHOICE value if initialised */
            i = asn1_get_choice_selector(pval, it);
            if ((i >= 0) && (i < it->tcount)) {
                tt = it->templates + i;
                pchptr = asn1_get_field_ptr(pval, tt);
                ASN1_template_free(pchptr, tt);
                asn1_set_choice_selector(pval, -1, it);
            }
        } else if (!ASN1_item_ex_new(pval, it)) {
            ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
            goto err;
        }
@@ -385,6 +392,17 @@ int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
        if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
            goto auxerr;

        /* Free up and zero any ADB found */
        for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
            if (tt->flags & ASN1_TFLG_ADB_MASK) {
                const ASN1_TEMPLATE *seqtt;
                ASN1_VALUE **pseqval;
                seqtt = asn1_do_adb(pval, tt, 1);
                pseqval = asn1_get_field_ptr(pval, seqtt);
                ASN1_template_free(pseqval, seqtt);
            }
        }

        /* Get each field entry */
        for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
            const ASN1_TEMPLATE *seqtt;