ComputerSurge/bind9
3
0
Fork 0
Code Pull Requests 1 Activity

Merge branch '3439-stop-resolving-invalid-names-in-resume_dslookup' into 'main'

Browse Source 
Stop resolving invalid names in resume_dslookup()

Closes #3439

See merge request isc-projects/bind9!6563
This commit is contained in:
Michał Kępień
2022-07-13 08:59:30 +00:00
parent 75027bc6ce cfa398ad37
commit 5415ecbd7c
3 changed files with 34 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
CHANGES
View File

@@ -1,3 +1,10 @@
5925. [bug] With a forwarder configured for all queries, resolution
failures encountered during DS chasing could trigger
assertion failures due to a logic bug in
resume_dslookup() that caused it to call
dns_resolver_createfetch() with an invalid name.
[GL #3439]
5924. [func] When it's necessary to use AXFR to respond to an
IXFR request, a message explaining the reason
is now logged at level info. [GL #2683]

6
doc/notes/notes-current.rst
View File

@@ -40,6 +40,12 @@ Feature Changes
Bug Fixes
~~~~~~~~~
- When running as a validating resolver forwarding all queries to
another resolver, :iscman:`named` could crash with an assertion
failure. These crashes occurred when the configured forwarder sent a
broken DS response and :iscman:`named` failed its attempts to find a
proper one instead. This has been fixed. :gl:`#3439`
- A DNS compression would be applied on the root zone name if it is repeatedly
used in the same RRSet. :gl:`#3423`

30
lib/dns/resolver.c
View File

@@ -7343,22 +7343,34 @@ resume_dslookup(isc_task_t *task, isc_event_t *event) {
}
/*
* Get domain and nameservers from fctx->nsfetch
* before we destroy it.
* Get domain from fctx->nsfetch before we destroy it.
*/
domain = dns_fixedname_initname(&fixed);
dns_name_copy(fctx->nsfetch->private->domain, domain);
/*
* If the chain of resume_dslookup() invocations managed to
* chop off enough labels from the original DS owner name to
* reach the top of the namespace, no further progress can be
* made. Interrupt the DS chasing process, returning SERVFAIL.
*/
if (dns_name_equal(fctx->nsname, domain)) {
dns_resolver_destroyfetch(&fctx->nsfetch);
fctx_done_detach(&fctx, DNS_R_SERVFAIL);
return;
}
/*
* Get nameservers from fctx->nsfetch before we destroy it.
*/
dns_rdataset_init(&nameservers);
if (dns_rdataset_isassociated(
&fctx->nsfetch->private->nameservers)) {
domain = dns_fixedname_initname(&fixed);
dns_name_copy(fctx->nsfetch->private->domain, domain);
if (dns_name_equal(fctx->nsname, domain)) {
dns_resolver_destroyfetch(&fctx->nsfetch);
fctx_done_detach(&fctx, DNS_R_SERVFAIL);
return;
}
dns_rdataset_clone(&fctx->nsfetch->private->nameservers,
&nameservers);
nsrdataset = &nameservers;
} else {
domain = NULL;
}
dns_resolver_destroyfetch(&fctx->nsfetch);