If too many versions of log / dnstap files to be saved where requests
the memory after to_keep could be overwritten. Force the number of
versions to be saved to a save level. Additionally the memmove length
was incorrect.
(cherry picked from commit 6ca78bc57d)
When "rndc reconfig" is run, named first configures a fresh set of views
and then tears down the old views. Consider what happens for a single
view with LMDB enabled; "envA" is the pointer to the LMDB environment
used by the original/old version of the view, "envB" is the pointer to
the same LMDB environment used by the new version of that view:
1. mdb_env_open(envA) is called when the view is first created.
2. "rndc reconfig" is called.
3. mdb_env_open(envB) is called for the new instance of the view.
4. mdb_env_close(envA) is called for the old instance of the view.
This seems to have worked so far. However, an upstream change [1] in
LMDB which will be part of its 0.9.26 release prevents the above
sequence of calls from working as intended because the locktable mutexes
will now get destroyed by the mdb_env_close() call in step 4 above,
causing any subsequent mdb_txn_begin() calls to fail (because all of the
above steps are happening within a single named process).
Preventing the above scenario from happening would require either
redesigning the way we use LMDB in BIND, which is not something we can
easily backport, or redesigning the way BIND carries out its
reconfiguration process, which would be an even more severe change.
To work around the problem, set MDB_NOLOCK when calling mdb_env_open()
to stop LMDB from controlling concurrent access to the database and do
the necessary locking in named instead. Reuse the view->new_zone_lock
mutex for this purpose to prevent the need for modifying struct dns_view
(which would necessitate library API version bumps). Drop use of
MDB_NOTLS as it is made redundant by MDB_NOLOCK: MDB_NOTLS only affects
where LMDB reader locktable slots are stored while MDB_NOLOCK prevents
the reader locktable from being used altogether.
[1] 2fd44e3251
(cherry picked from commit 53120279b5)
The ThreadSanitizer found a data race when updating the stale header.
Instead of trying to acquire the write lock and failing occasionally
which would skew the statistics, the dns_rdatasetheader_t.attributes
field has been promoted to use stdatomics. Updating the attributes in
the mark_header_ancient() and mark_header_stale() now uses the cmpxchg
to update the attributes forfeiting the need to hold the write lock on
the tree. Please note that mark_header_ancient() still needs to hold
the lock because .dirty is being updated in the same go.
(cherry picked from commit 81d4230e60)
The stdatomic shims for non-C11 compilers (Windows, old gcc, ...) and
mutexatomic implemented only and minimal subset of the atomic types.
This commit adds 16-bit operations for Windows and all atomic types as
defined in standard.
(cherry picked from commit bccea5862d)
BUFSIZ (512 bytes on Windows) may not be enough to fit the status of a
DNSSEC policy and three DNSSEC keys.
Set the size of the relevant buffer to a hardcoded value of 4096 bytes,
which should be enough for most scenarios.
(cherry picked from commit 9347e7db7e)
While the creation and publication times of the various keys
in this policy are nearly at the same time there is a chance that
one key is created a second later than the other.
The `set_keytimes_algorithm_policy` mistakenly set the keytimes
for KEY3 based of the "published" time from KEY2.
(cherry picked from commit 24e07ae98e)
Commit b580eb2fb3 inadvertently caused the
man pages for symlinked BIND tools (named-compilezone, tsig-keygen) to
no longer be installed by "make install". Fix by restoring the commands
which ensure that.
Commit b580eb2fb3 inadvertently caused
dnstap-related man pages to be installed unconditionally. Ensure they
are only installed for dnstap-enabled builds.
When we're coming back from recursion fetch_callback does not accept
DNS_R_NXDOMAIN as an rcode - query_gotanswer calls query_nxdomain in
which an assertion fails on qctx->is_zone. Yet, under some
circumstances, qname minimization will return an DNS_R_NXDOMAIN - when
root zone mirror is not yet loaded. The fix changes the DNS_R_NXDOMAIN
answer to DNS_R_SERVFAIL.
