Don't set choice selector on parse failure.

Don't set choice selector on parse failure: this can pass unexpected
values to the choice callback. Instead free up partial structure
directly.

CVE-2016-7053

Thanks to Tyler Nighswander of ForAllSecure for reporting this issue.

Reviewed-by: Richard Levitte <levitte@openssl.org>
This commit is contained in:
Dr. Stephen Henson 2016-10-14 11:51:43 +01:00 committed by Matt Caswell
parent bf52165bda
commit f962541d0b

View File

@ -225,16 +225,14 @@ static int asn1_item_embed_d2i(ASN1_VALUE **pval, const unsigned char **in,
/* If field not present, try the next one */
if (ret == -1)
continue;
/*
* Set the choice selector here to ensure that the value is
* correctly freed upon error. It may be partially initialized
* even if parsing failed.
*/
asn1_set_choice_selector(pval, i, it);
/* If positive return, read OK, break loop */
if (ret > 0)
break;
/* Otherwise must be an ASN1 parsing error */
/*
* Must be an ASN1 parsing error.
* Free up any partial choice value
*/
asn1_template_free(pchptr, tt);
errtt = tt;
ASN1err(ASN1_F_ASN1_ITEM_EMBED_D2I, ERR_R_NESTED_ASN1_ERROR);
goto err;
@ -252,6 +250,8 @@ static int asn1_item_embed_d2i(ASN1_VALUE **pval, const unsigned char **in,
goto err;
}
asn1_set_choice_selector(pval, i, it);
if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
goto auxerr;
*in = p;