When a catalog zone is updated using AXFR, the zone database is changed,
so it is required to unregister the update notification callback from
the old database, and register it for the new one.
Currently, here is the order of the steps happening in such scenario:
1. The zone.c:zone_startload() function registers the notify callback
on the new database using dns_zone_catz_enable_db()
2. The callback, when called, notices that the new 'db' is different
than 'catz->db', and unregisters the old callback for 'catz->db',
marks that it's unregistered by setting 'catz->db_registered' to
false, then it schedules an update if it isn't already scheduled.
3. The offloaded update process, after completing its job, notices that
'catz->db_registered' is false, and (re)registers the update callback
for the current database it is working on. There is no harm here even
if it was registered also on step 1, and we can't skip it, because
this function can also be called "artificially" during a
reconfiguration, and in that case the registration step is required
here.
A problem arises when before step 1 an update process was already
in a running state, operating on the old database, and finishing its
work only after step 2. As described in step 3, dns__catz_update_cb()
notices that 'catz->db_registered' is false and registers the callback
on the current database it is working on, which, at that state, is
already obsolete and unused by the zone. When it detaches the database,
the function which is responsible for its cleanup (e.g. free_rbtdb())
asserts because there is a registered update notify callback there.
To fix the problem, instead of delaying the (re)registration to step 3,
make sure that the new callback is registered and 'catz->db_registered'
is accordingly marked on step 2.
(cherry picked from commit 998765fea5)
The purpose of the check is to verify the server has survived the
previous barrage of queries. This is done by sending a query and
checking we get a NOERROR response back.
Previously, that query could've been affected by a servfail cache - the
server would return a SERVFAIL answer, thus failing the check, despite
being up and running. Use version.bind txt ch query to avoid the
interference of servfail cache.
(cherry picked from commit dd7bcd2855)
The number of clients per query is calculated using the pending
fetch responses in the list. The dns_resolver_createfetch() function
includes every item in the list when deciding whether the limit is
reached (i.e. fctx->spilled is true). Then, when the limit is reached,
there is another calculation in fctx_sendevents(), when deciding
whether it is needed to increase the limit, but this time the TRYSTALE
responses are not included in the calculation (because of early break
from the loop), and because of that the limit is never increased.
A single client can have more than one associated response/event in the
list (currently max. two), and calculating them as separate "clients"
is unexpected. E.g. if 'stale-answer-enable' is enabled and
'stale-answer-client-timeout' is enabled and is larger than 0, then
each client will have two events, which will effectively halve the
clients-per-query limit.
Fix the dns_resolver_createfetch() function to calculate only the
regular FETCHDONE responses/events.
Change the fctx_sendevents() function to also calculate only FETCHDONE
responses/events. Currently, this second change doesn't have any impact,
because the TRYSTALE events were already skipped, but having the same
condition in both places will help prevent similar bugs in the future
if a new type of response/event is ever added.
(cherry picked from commit 2ae5c4a674)
Check if clients-per-query quota works as expected with or without
a positive stale-answer-client-timeout value and serve-stale answers
enabled.
(cherry picked from commit 3bb2babcd0)
Prepare the fetchlimit system test for adding a clients-per-query
check. Change some functions and commands to accept a destination
NS IP address instead of using the hardcoded 10.53.0.3.
(cherry picked from commit 7ebd055c78)
1. Fix the numbering.
2. Fix an artifacts rewriting issue.
3. Add missing checks of 'ret' after some checks.
4. Fix extracting the quota value from the ADB dump.
(cherry picked from commit 101d829b02)
This commit changes send buffers allocation strategy for stream based
transports. Before that change we would allocate a dynamic buffers
sized at 64Kb even when we do not need that much. That could lead to
high memory usage on server. Now we resize the send buffer to match
the size of the actual data, freeing the memory at the end of the
buffer for being reused later.
(cherry picked from commit d8a5feb556)
There is a lock-order-inversion (potential deadlock) in resolver.c,
because in dns_resolver_shutdown() a resolver bucket lock is locked
while the resolver lock itself is already locked, while in
fctx_sendevents() the resolver lock is locked while a bucket lock
is locked before calling that function in fctx__done_detach().
The resolver lock/unlock in dns_resolver_shutdown() was added back in
the 317e36d47e commit to make sure that
the function is finished before the resolver object is destroyed.
Since res->exiting is atomic, it should be possible to remove the
resolver locking in dns_resolver_shutdown() and add it to the
send_shutdown_events() function which requires it.
Also, since 'res->exiting' is now set while unlocked, the 'INSIST'
in spillattimer_countdown() is wrong, and is removed.
The reference manual doesn't document all the available resolver
statistics counters. Add information about the missing counters.
(cherry picked from commit 08ebf39d1e)
This counter indicates the number of the resolver's spilled
queries due to reaching the clients per query quota.
(cherry picked from commit 04648d7c2f)
The get_core_dumps.sh script couldn't find and process core files of
out-of-tree configurations because it looked for them in the source
instead of the build directory.
(cherry picked from commit a13448a769)
Fedora 38 and Debian "bullseye" images were "forked" to images used only
for TSAN CI jobs. The new images contain TSAN-aware liburcu that does
not fit well with ASAN CI jobs for which original images were also used.
liburcu is not used in this branch, but images are shared among
branches, and their use needs to be consistent in all maintained
branches.
(cherry picked from commit 04dda8661f)
The selected base port should be in the range <port_min, port_max), the
formula was incorrect.
Credit for discovering this fault goes to Ondrej Sury.
(cherry picked from commit e8ea6b610b)
We recently fixed a bug where in some cases (when following an
expired CNAME for example), named could return SERVFAIL if the target
record is still valid (see isc-projects/bind9#3678, and
isc-projects/bind9!7096). We fixed this by considering non-stale
RRsets as well during the stale lookup.
However, this triggered a new bug because despite the answer from
cache not being stale, the lookup may be triggered by serve-stale.
If the answer from database is not stale, the fix in
isc-projects/bind9!7096 erroneously skips the serve-stale logic.
Add 'answer_found' checks to the serve-stale logic to fix this issue.
(cherry picked from commit bbd163acf6)
Add a test case where when priming the cache with a slow authoritative
resolver, the stale-answer-client-timeout option should not return
a delegation to the client (it should wait until an applicable answer
is found, if no entry is found in the cache).
(cherry picked from commit c3d4fd3449)
Since we don't use networking directly but rather via libuv, these
configure options were no-op. Remove the configure checks for epoll
(Linux), kqueue (BSDs) and /dev/poll (Solaris).
(cherry picked from commit 051f3d612f)
These insertions are added to produce a radix tree that will trigger
the INSIST reported in [GL #4090]. Due to fixes added since BIND 9.9
an extra insert in needed to ensure node->parent is non NULL.
(cherry picked from commit 03ebe96110)
isc_mem_put NULL's the pointer to the memory being freed. The
equality test 'parent->r == node' was accidentally being turned
into a test against NULL.
(cherry picked from commit ac2e0bc3ff)
