Description of problem:



Unchecked NULL pointer issue

Function regional_alloc() is used to allocate memory. There is a call to it in function dns64_operate() within dns64/dns64.c where if the call to regional_alloc() fails and iq is not properly checked it could lead to operations being done on a NULL pointer. Everywhere else in the codebase there is proper error checking after a call to regional_alloc() which logs "out of memory" and returns


    switch(event) {
        case module_event_new:
            /* Tag this query as being new and fall through. */
            iq = (struct dns64_qstate*)regional_alloc(
                qstate->region, sizeof(*iq));
            qstate->minfo[id] = iq; 
            iq->state = DNS64_NEW_QUERY;
            iq->started_no_cache_store = qstate->no_cache_store;
            qstate->no_cache_store = 1;  
            /* fallthrough */



Some similar issues have been fixed earlier via following commit
https://github.com/NLnetLabs/unbound/commit/2a4e840be42974543e7702eebab35d82c0fe0088



Version-Release number of selected component (if applicable):

I used version unbound-1.13.1-5.el9.rpm while auditing, however I've verified with upstream code base as well, the issue exists there too


How reproducible:


Steps to Reproduce:
1.
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Actual results:

regional_alloc() failure is not accounted for as in this case, however it is used elsewhere in the codebase where its failure is checked via an if condition


Expected results:

regional_alloc() failure should be accounted for


Additional info: