bind9/bin/dig
Aram Sargsyan b23d88947a DiG: fix lookup reference counting bug
When DiG finishes its work with a lookup (due to success or error), it
calls the clear_current_lookup() function, which decreases the lookup's
reference count. That decrease action is the counterpart of the initial
creation of the reference counter, so this function was designed in such
a way that it should decrease the reference count only once, when there
are no more active queries in the lookup.

The way it checks whether there are any active queries is by looking
at the queries list of the lookup object - if it's NULL then there are
no active queries. But that is not always true - the cancel_lookup()
function, when canceling the queries one by one, also removes them
from the lookup's list, but in NSSEARCH mode, when the queries are
working in parallel, some of those queries can be still active. And
when their recv_done() callback gets called, it sees that the lookup
has been canceled, calls clear_current_lookup(), which decreases the
reference count every time for each query that was still active
(because ISC_LIST_HEAD(lookup->q) is NULL) and results in a reference
counting error.

Fix the issue by introducing a new "cleared" property for the lookup,
which will ensure that the clear_current_lookup() function does its
job only once per lookup.

(cherry picked from commit 08ba2732e061710d3622ae181de33bbaaf63f63c)
2022-08-08 10:48:38 +00:00
..
.gitignore [master] update gitignore files; use rev-parse to get srcid 2014-06-17 13:49:30 -07:00
dig.c DiG: document +qid=<num> option in the usage summary 2022-07-28 09:14:56 +00:00
dig.rst Add support for Strict/Mutual TLS to dig 2022-04-28 13:39:21 +03:00
dighost.c DiG: fix lookup reference counting bug 2022-08-08 10:48:38 +00:00
dighost.h DiG: fix lookup reference counting bug 2022-08-08 10:48:38 +00:00
host.c Initialize printed buffer 2022-04-29 11:46:22 +10:00
host.rst Add internal hyperlinks to See Also section of manual pages 2022-03-14 11:01:32 +01:00
Makefile.am Move the include Makefile.tests to the bottom of Makefile.am(s) 2021-06-24 15:33:52 +02:00
nslookup.c Replace ISC_NORETURN with C11's noreturn 2022-03-25 08:42:18 +01:00
nslookup.rst Add internal hyperlinks to See Also section of manual pages 2022-03-14 11:01:32 +01:00
readline.h Update the copyright information in all files in the repository 2022-01-11 09:05:02 +01:00