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Wireshark-dev: Re: [Wireshark-dev] OID/BER memory oddness

From: Ed Beroset <beroset@xxxxxxxxxxxxxx>
Date: Sun, 15 Dec 2013 14:20:06 -0500
Ed Beroset wrote:
Evan Huus wrote:

The part that's confusing me is that somehow
actx->external.direct_reference seems to be getting a pointer to this
stale ep-allocated buffer, but I can't find anywhere in the call stack
that value could be set to such a stale buffer.

That would probably be dissect_ber_OBJECT_IDENTIFIER which calls
dissect_ber_object_identifier_str(), which calls
dissect_ber_any_oid_str() which calls oid_encoded2string.

As a correction, I was looking a little more at your original message with the trace, and I think that in your case it's more likely to be the call to dissect_x509af_T_extnId(). It's the line that's created by the DEFAULT_BODY line in asn1/x509af/x509af.cnf line 90. If you look at the generated code, you'll see that it creates a call to dissect_ber_object_identifier_str() the last parameter of which is &actx->external.direct_reference.

Ed