ret->link.next is tested to see if it is NULL unlocked
to avoid obtaining taillock when it is not nexessary then
retested once the taillock is obtained.
Now that the log message has been printed set the result code to
DNS_R_FORMERR. We don't do this via dns_result_torcode() as we
don't want upstream errors to produce FORMERR if that processing
end with DNS_R_BADTSIG.
(cherry picked from commit 20488d6ad3)
server might be created, but not yet fully initialized, when fatal
function is called. Check both server and task before attaching
exclusive task.
(cherry picked from commit c5e7152cf0)
it was possible for the count_newzones() function to try to
unlock view->new_zone_lock on return before locking it, which
caused a crash on shutdown.
(cherry picked from commit ed37c63e2b)
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] https://git.openldap.org/openldap/openldap/-/commit/2fd44e325195ae81664eb5dc36e7d265927c5ebc
(cherry picked from commit 53120279b5)
enough buffer space. Also change named_os_uname() prototype so
that it is now returning (const char *) rather than (char *). If
uname() is not supported on a UNIX build prepopulate unamebuf[]
with "unknown architecture".
(cherry picked from commit 4bc3de070f)
named_os_openfile was being called with switch_user set to true
unconditionally leading to log messages about being unable to
switch user identity from named when regenerating the key.
(cherry picked from commit 071bc29962)
When running on Linux and system capabilities are available, named will
drop the extra capabilities before loading the configuration. This led
to spurious warnings from `seteuid()` because named already dropped
CAP_SETUID and CAP_GETUID capabilities.
The fix removes setting the effective uid/gid when capabilities are
available, and adds a check that we are running under the user we were
requested to run.
(cherry picked from commit 6c82e2af92)
All our MSVS Project files share the same intermediate directory. We
know that this doesn't cause any problems, so we can just disable the
detection in the project files.
Example of the warning:
warning MSB8028: The intermediate directory (.\Release\) contains files shared from another project (dnssectool.vcxproj). This can lead to incorrect clean and rebuild behavior.
(cherry picked from commit b6c2012d93)
Our vcxproj files set the WarningLevel to Level3, which is too verbose
for a code that needs to be portable. That basically leads to ignoring
all the errors that MSVC produces. This commits downgrades the
WarningLevel to Level1 and enables treating warnings as errors for
Release builds. For the Debug builds the WarningLevel got upgraded to
Level4, and treating warnings as errors is explicitly disabled.
We should eventually make the code clean of all MSVC warnings, but it's
a long way to go for Level4, so it's more reasonable to start at Level1.
For reference[1], these are the warning levels as described by MSVC
documentation:
* /W0 suppresses all warnings. It's equivalent to /w.
* /W1 displays level 1 (severe) warnings. /W1 is the default setting
in the command-line compiler.
* /W2 displays level 1 and level 2 (significant) warnings.
* /W3 displays level 1, level 2, and level 3 (production quality)
warnings. /W3 is the default setting in the IDE.
* /W4 displays level 1, level 2, and level 3 warnings, and all level 4
(informational) warnings that aren't off by default. We recommend
that you use this option to provide lint-like warnings. For a new
project, it may be best to use /W4 in all compilations. This option
helps ensure the fewest possible hard-to-find code defects.
* /Wall displays all warnings displayed by /W4 and all other warnings
that /W4 doesn't include — for example, warnings that are off by
default.
* /WX treats all compiler warnings as errors. For a new project, it
may be best to use /WX in all compilations; resolving all warnings
ensures the fewest possible hard-to-find code defects.
1. https://docs.microsoft.com/en-us/cpp/build/reference/compiler-option-warning-level?view=vs-2019
(cherry picked from commit 789d253e3d)
some empty conditional branches which contained a semicolon were
"fixed" by clang-format to contain nothing. add comments to prevent this.
(cherry picked from commit 735be3b816)
cppcheck 1.90 reports the following issue for bin/named/query.c:
bin/named/query.c:6838:2: warning: %d in format string (no. 3) requires 'int' but the argument type is 'unsigned int'. [invalidPrintfArgType_sint]
snprintf(mbuf, sizeof(mbuf) - 1,
^
Tweak the format specifier for client->query.restarts to address the
problem.
Before this change, there was a missing blank line between the
negative trust anchors for one view, and the heading line for the next
view. This is because dns_ntatable_totext() omits the last newline.
There is an example of the incorrect output below; the fixed output
has a blank line before "Start view auth".
secure roots as of 21-Oct-2019 12:03:23.500:
Start view rec
Secure roots:
./RSASHA256/20326 ; managed
Negative trust anchors:
example.com: expiry 21-Oct-2019 13:03:15.000
Start view auth
Secure roots:
./RSASHA256/20326 ; managed
Negative trust anchors:
example.com: expiry 21-Oct-2019 13:03:07.000
(cherry picked from commit 5b600c2cd8)
Libmaxmind does not provide any version macro for link time version.
Print at least runtime version library used, if linked.
(cherry picked from commit e6d7384c0d)
xmlInitThreads() and xmlCleanupThreads() are called from within
ns_statschannels_configure() and ns_statschannels_shutdown(),
respectively. Both of these functions are executed by worker threads,
not the main named thread. This causes ASAN to report memory leaks like
the following one upon shutdown (as long as named is asked to produce
any XML output over its configured statistics channels during its
lifetime):
Direct leak of 968 byte(s) in 1 object(s) allocated from:
#0 0x7f677c249cd8 in __interceptor_calloc /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cc:153
#1 0x7f677bc1838f in xmlGetGlobalState (/usr/lib/libxml2.so.2+0xa838f)
The data mentioned in the above report is a libxml2 state structure
stored as thread-specific data. Such chunks of memory are automatically
released (by a destructor passed to pthread_key_create() by libxml2)
whenever a thread that allocated a given chunk exits. However, if
xmlCleanupThreads() is called by a given thread before it exits, the
destructor will not be invoked (due to xmlCleanupThreads() calling
pthread_key_delete()) and ASAN will report a memory leak. Thus,
xmlInitThreads() and xmlCleanupThreads() must not be called from worker
threads. Since xmlInitThreads() must be called on Windows in order for
libxml2 to work at all, move xmlInitThreads() and xmlCleanupThreads()
calls to the main named thread (which does not produce any XML output
itself) in order to prevent the memory leak from being reported by ASAN.
(cherry picked from commit b425b5d56e)
Loaded GeoIP2 databases are only released when named is shut down, but
not during server reconfiguration. This causes memory to be leaked
every time "rndc reconfig" or "rndc reload" is used, as long as any
GeoIP2 database is in use. Fix by releasing any loaded GeoIP2 databases
before reloading them. Do not call dns_geoip_shutdown() until server
shutdown as that function releases the memory context used for caching
GeoIP2 lookup results.
(cherry picked from commit 670afbe84a)
When loading the configuration fails, there might be already other tasks
running and calling OpenSSL library functions. The OpenSSL on_exit
handler is called when exiting the main process and there's a timing
race between the on_exit function that destroys OpenSSL allocated
resources (threads, locks, ...) and other tasks accessing the very same
resources leading to a crash in the system threading library. Therefore,
the fatal() function needs to request exlusive access to the task
manager to finish the already running tasks and exit only when no other
tasks are running.
(cherry picked from commit 952d7fde63)
Previously, there was no limit to the number of concurrently served
queries over one pipelined TCP connection; an unlimited number of
queries sent over a single TCP connection could have potentially
exhausted the server's resources.
This variable will report the maximum number of simultaneous tcp clients
that BIND has served while running.
It can be verified by running rndc status, then inspect "tcp high-water:
count", or by generating statistics file, rndc stats, then inspect the
line with "TCP connection high-water" text.
The tcp-highwater variable is atomically updated based on an existing
tcp-quota system handled in ns/client.c.
(cherry picked from commit 66fe8627de)
The named_g_defaultdnstap was never used as the dnstap requires
explicit configuration of the output file.
Related scan-build report:
./server.c:3476:14: warning: Value stored to 'dpath' during its initialization is never read
const char *dpath = named_g_defaultdnstap;
^~~~~ ~~~~~~~~~~~~~~~~~~~~~
1 warning generated.
(cherry picked from commit 6decd14592)