In recv_done(), when dig decides to start the lookup's next query in
the line using `start_udp()` or `start_tcp()`, and for some reason,
no queries get started, dig doesn't cancel the lookup.
This can occur, for example, when there are two queries in the lookup,
one with a regular IP address, and another with a IPv4 mapped IPv6
address. When the regular IP address fails to serve the query, its
`recv_done()` callback starts the next query in the line (in this
case the one with a mapped IP address), but because `dig` doesn't
connect to such IP addresses, and there are no other queries in the
list, no new queries are being started, and the lookup keeps hanging.
After calling `start_udp()` or `start_tcp()` in `recv_done()`, check
if there are no pending/working queries then cancel the lookup instead
of only detaching from the current query.
(cherry picked from commit 7e2f50c369)
a test case in the 'resolver' system test was reliant on
logged output that would only be present when query tracing
was enabled, as in developer builds. that test case is now
disabled when query tracing is not available. Thanks to
Anton Castelli.
(cherry picked from commit 5319d8adea)
The `udp_ready()` and `tcp_connected()` functions in dighost.c are
used for similar purposes for UDP and TCP respectively.
Synchronize the `udp_ready()` function entry code to behave like
`tcp_connected()` by adding input validation, debug messages and
early exit code when `cancel_now` is `true`.
(cherry picked from commit 4477f71868)
When finishing the NSSEARCH task and there is no more followup
lookups to start, dig does not destroy the last lookup, which
causes it to hang indefinitely.
Rename the unused `first_pass` member of `dig_query_t` to `started`
and make it `true` in the first callback after `start_udp()` or
`start_tcp()` of the query to indicate that the query has been
started.
Create a new `check_if_queries_done()` function to check whether
all of the queries inside a lookup have been started and finished,
or canceled.
Use the mentioned function in the TRACE code block in `recv_done()`
to check whether the current query is the last one in the lookup and
cancel the lookup in that case to free the resources.
(cherry picked from commit 7d360bd05e)
the line "$GENERATE 19-28/2147483645 $ CNAME x" should generate
a single CNAME with the owner "19.example.com", but prior to the
overflow bug it generated several CNAMEs, half of them with large
negative values.
we now test for the bugfix by using "named-checkzone -D" and
grepping for a single CNAME in the output.
(cherry picked from commit bd814b79d4)
the value of 'i' in generate could overflow when adding 'step' to
it in the 'for' loop. Use an unsigned int for 'i' which will give
an additional bit and prevent the overflow. The inputs are both
less than 2^31 and and the result will be less than 2^32-1.
(cherry picked from commit 5abdee9004)
Ensure the update zone name is mentioned in the NOTAUTH error message
in the server log, so that it is easier to track down problematic
update clients. There are two cases: either the update zone is
unrelated to any of the server's zones (previously no zone was
mentioned); or the update zone is a subdomain of one or more of the
server's zones (previously the name of the irrelevant parent zone was
misleadingly logged).
Closes#3209
(cherry picked from commit 84c4eb02e7)
In couple places, we have missed INSIST(0) or ISC_UNREACHABLE()
replacement on some branches with UNREACHABLE(). Replace all
ISC_UNREACHABLE() or INSIST(0) calls with UNREACHABLE().
There is a possible code path of using the uninitialized `bname`
character array while logging an error message.
Initialize the `bname` buffer earlier in the function.
Also, change the initialization routine to use a helper function.
(cherry picked from commit a5a6362e92)
A successful call to `dns_rdata_tostruct()` expects an accompanying
call to `dns_rdata_freestruct()` to free up any memory that could have
been allocated during the first call.
In catz.c there are several places where `dns_rdata_freestruct()` call
is skipped.
Add the missing cleanup routines.
(cherry picked from commit f57c51fe05)
Because of the "goto" in the "if" body the "else" part is unnecessary
and adds another level of indentation.
Cleanup the code to not have the "else" part.
(cherry picked from commit 9b84bfb5f4)
Catz logs a warning message when it is told to modify a zone which was
not added by the current catalog zone.
When logging a warning, distinguish the two cases when the zone
was not added by a catalog zone at all, and when the zone was
added by a different catalog zone.
(cherry picked from commit d29e5f197b)
The current function's name in one of the error logs in
catz_addmodzone_taskaction() function is invalid.
Fix the name.
(cherry picked from commit e861224cf4)
Quote the dns64 prefix in error messages that complain about
problems with it, to avoid confusion with the following ACLs.
Closes#3210
(cherry picked from commit 496c02d32a)
Some ancient versions of clang reported uninitialized memory use false
positive (see https://bugs.llvm.org/show_bug.cgi?id=14461). Since clang
4.0.1 has been long obsoleted, just remove the workarounds.
(cherry picked from commit ae508c17bc)
Historically, the inline keyword was a strong suggestion to the compiler
that it should inline the function marked inline. As compilers became
better at optimising, this functionality has receded, and using inline
as a suggestion to inline a function is obsolete. The compiler will
happily ignore it and inline something else entirely if it finds that's
a better optimisation.
Therefore, remove all the occurences of the inline keyword with static
functions inside single compilation unit and leave the decision whether
to inline a function or not entirely on the compiler
NOTE: We keep the usage the inline keyword when the purpose is to change
the linkage behaviour.
(cherry picked from commit 20f0936cf2)
C11 has builtin support for _Noreturn function specifier with
convenience noreturn macro defined in <stdnoreturn.h> header.
Replace ISC_NORETURN macro by C11 noreturn with fallback to
__attribute__((noreturn)) if the C11 support is not complete.
(cherry picked from commit 04d0b70ba2)
Previously, the unreachable code paths would have to be tagged with:
INSIST(0);
ISC_UNREACHABLE();
There was also older parts of the code that used comment annotation:
/* NOTREACHED */
Unify the handling of unreachable code paths to just use:
UNREACHABLE();
The UNREACHABLE() macro now asserts when reached and also uses
__builtin_unreachable(); when such builtin is available in the compiler.
(cherry picked from commit 584f0d7a7e)
Gcc 7+ and Clang 10+ have implemented __attribute__((fallthrough)) which
is explicit version of the /* FALLTHROUGH */ comment we are currently
using.
Add and apply FALLTHROUGH macro that uses the attribute if available,
but does nothing on older compilers.
In one case (lib/dns/zone.c), using the macro revealed that we were
using the /* FALLTHROUGH */ comment in wrong place, remove that comment.
(cherry picked from commit fe7ce629f4)
When the parse tsan files have text extension they can be viewed
directly in the GitLab web UI without downloading them locally.
(cherry picked from commit 80582073a5)
From an attacker's point of view, a VLA declaration is essentially a
primitive for performing arbitrary arithmetic on the stack pointer. If
the attacker can control the size of a VLA they have a very powerful
tool for causing memory corruption.
To mitigate this kind of attack, and the more general class of stack
clash vulnerabilities, C compilers insert extra code when allocating a
VLA to probe the growing stack one page at a time. If these probes hit
the stack guard page, the program will crash.
From the point of view of a C programmer, there are a few things to
consider about VLAs:
* If it is important to handle allocation failures in a controlled
manner, don't use VLAs. You can use VLAs if it is OK for
unreasonable inputs to cause an uncontrolled crash.
* If the VLA is known to be smaller than some known fixed size,
use a fixed size array and a run-time check to ensure it is large
enough. This will be more efficient than the compiler's stack
probes that need to cope with arbitrary-size VLAs.
* If the VLA might be large, allocate it on the heap. The heap
allocator can allocate multiple pages in one shot, whereas the
stack clash probes work one page at a time.
Most of the existing uses of VLAs in BIND are in test code where they
are benign, but there was one instance in `named`, in the GSS-TSIG
verification code, which has now been removed.
This commit adjusts the style guide and the C compiler flags to allow
VLAs in test code but not elsewhere.
(cherry picked from commit 599c1d2a6b)
In the GSS-TSIG verification code there was an alarming
variable-length array whose size came off the network, from the
signature in the request. It turned out to be safe, because the caller
had previously checked that the signature had a reasonable size.
However, the safety checks are in the generic TSIG implementation, and
the risky VLA usage was in the GSS-specific code, and they are
separated by the DST indirection layer, so it wasn't immediately
obvious that the risky VLA was in fact safe.
In fact this risky VLA was completely unnecessary, because the GSS
signature can be verified in place without being copied to the stack,
like the message covered by the signature. The `REGION_TO_GBUFFER()`
macro backwardly assigns the region in its left argument to the GSS
buffer in its right argument; this is just a pointer and length
conversion, without copying any data. The `gss_verify_mic()` call uses
both message and signature GSS buffers in a read-only manner.
(cherry picked from commit eeead1cfe7)
Rework the "ans8" server in the "digdelv" system test to support various
modes of operations using a control channel.
The supported modes are:
1. `silent` (do not respond)
2. `close` (UDP: same as `silent`; TCP: also close the connection)
3. `servfail` (always respond with `SERVFAIL`)
4. `unstable` (constantly switch between `silent` and `servfail`)
Add multiple tests to check the handling of both TCP and UDP socket
error scenarios in dig/host.
(cherry picked from commit 03697f1bcc)
When encountering a TCP connection error while trying to initiate a
connection to a server, dig erroneously cancels the lookup even when
there are other server(s) to try, which results in an assertion failure.
Cancel the lookup only when there are no more queries left in the
lookup's queries list (i.e. `next` is NULL).
(cherry picked from commit 0fb4fc1897)
Add a test to check whether dig tries the next query/server after
a connection error.
Add a test to check whether dig tries the next query/server after
a one or more (default is 3) connection/request timeouts.
(cherry picked from commit e8a64d0cbe)
When timing-out or having other types of socket errors during a query,
dig isn't trying to perform the lookup using other servers which exist
in the lookup's queries list.
After configured amount of timeout retries, or after a socket error,
check if there are other queries/servers in the lookup's queries list,
and start the next one if it exists, instead of unconditionally failing.
(cherry picked from commit bc203d6082)
