in case the rdb child failed, crashed or terminated unexpectedly redis
would have marked the replica clients with repl_put_online_on_ack and
then kill them only after a minute when no ack was received.
it would not stream anything to these connections, so the only effect of
this bug is a delay of 1 minute in the replicas attempt to re-connect.
* fix description about ZIP_BIG_PREVLEN(the code is ok), it's similar to
antirez#4705
* fix description about ziplist entry encoding field (the code is ok),
the max length should be 2^32 - 1 when encoding is 5 bytes
* Tests: fix and reintroduce redis-cli tests.
These tests have been broken and disabled for 10 years now!
* TLS: add remaining redis-cli support.
This adds support for the redis-cli --pipe, --rdb and --replica options
previously unsupported in --tls mode.
* Fix writeConn().
Similarly to EXPIREAT with TTL in the past, which implicitly deletes the
key and return success, RESTORE should not store key that are already
expired into the db.
When used together with REPLACE it should emit a DEL to keyspace
notification and replication stream.
* tests/valgrind: don't use debug restart
DEBUG REATART causes two issues:
1. it uses execve which replaces the original process and valgrind doesn't
have a chance to check for errors, so leaks go unreported.
2. valgrind report invalid calls to close() which we're unable to resolve.
So now the tests use restart_server mechanism in the tests, that terminates
the old server and starts a new one, new PID, but same stdout, stderr.
since the stderr can contain two or more valgrind report, it is not enough
to just check for the absence of leaks, we also need to check for some known
errors, we do both, and fail if we either find an error, or can't find a
report saying there are no leaks.
other changes:
- when killing a server that was already terminated we check for leaks too.
- adding DEBUG LEAK which was used to test it.
- adding --trace-children to valgrind, although no longer needed.
- since the stdout contains two or more runs, we need slightly different way
of checking if the new process is up (explicitly looking for the new PID)
- move the code that handles --wait-server to happen earlier (before
watching the startup message in the log), and serve the restarted server too.
* squashme - CR fixes
For example:
BITOP not targetkey sourcekey
If targetkey and sourcekey doesn't exist, BITOP has no effect,
we do not propagate it, thus can save aof and replica flow.
In order to support the use of multi-exec in pipeline, it is important that
MULTI and EXEC are never rejected and it is easy for the client to know if the
connection is still in multi state.
It was easy to make sure MULTI and DISCARD never fail (done by previous
commits) since these only change the client state and don't do any actual
change in the server, but EXEC is a different story.
Since in the past, it was possible for clients to handle some EXEC errors and
retry the EXEC, we now can't affort to return any error on EXEC other than
EXECABORT, which now carries with it the real reason for the abort too.
Other fixes in this commit:
- Some checks that where performed at the time of queuing need to be re-
validated when EXEC runs, for instance if the transaction contains writes
commands, it needs to be aborted. there was one check that was already done
in execCommand (-READONLY), but other checks where missing: -OOM, -MISCONF,
-NOREPLICAS, -MASTERDOWN
- When a command is rejected by processCommand it was rejected with addReply,
which was not recognized as an error in case the bad command came from the
master. this will enable to count or MONITOR these errors in the future.
- make it easier for tests to create additional (non deferred) clients.
- add tests for the fixes of this commit.
The scan key module API provides the scan callback with the current
field name and value (if it exists). Those arguments are RedisModuleString*
which means it supposes to point to robj which is encoded as a string.
Using createStringObjectFromLongLong function might return robj that
points to an integer and so break a module that tries for example to
use RedisModule_StringPtrLen on the given field/value.
The PR introduces a fix that uses the createObject function and sdsfromlonglong function.
Using those function promise that the field and value pass to the to the
scan callback will be Strings.
The PR also changes the Scan test module to use RedisModule_StringPtrLen
to catch the issue. without this, the issue is hidden because
RedisModule_ReplyWithString knows to handle integer encoding of the
given robj (RedisModuleString).
The PR also introduces a new test to verify the issue is solved.
The `LRANK` command returns the index (position) of a given element
within a list. Using the `direction` argument it is possible to specify
going from head to tail (acending, 1) or from tail to head (decending,
-1). Only the first found index is returend. The complexity is O(N).
When using lists as a queue it can be of interest at what position a
given element is, for instance to monitor a job processing through a
work queue. This came up within the Python `rq` project which is based
on Redis[0].
[0]: https://github.com/rq/rq/issues/1197
Signed-off-by: Paul Spooren <mail@aparcar.org>
the recent change in that loop (iteration rather than waiting for it to
be empty) was intended to avoid an endless loop in case some slave would
refuse to be freed.
but the lookup of the first client remained, which would have caused it
to try the first one again and again instead of moving on.
Much like MULTI/EXEC/DISCARD, the WATCH and UNWATCH are not actually
operating on the database or server state, but instead operate on the
client state. the client may send them all in one long pipeline and check
all the responses only at the end, so failing them may lead to a
mismatch between the client state on the server and the one on the
client end, and execute the wrong commands (ones that were meant to be
discarded)
the watched keys are not actually stored in the client struct, but they
are in fact part of the client state. for instance, they're not cleared
or moved in SWAPDB or FLUSHDB.
Now it is also possible for ACL SETUSER to accept empty strings
as valid operations (doing nothing), so for instance
ACL SETUSER myuser ""
Will have just the effect of creating a user in the default state.
This should fix#7329.
This impacts client verification for chained certificates (such as Lets
Encrypt certificates). Client Verify requires the full chain in order to
properly verify the certificate.
After a closer look, the Redis core devleopers all believe that this was
too fragile, caused many bugs that we didn't expect and that were very
hard to track. Better to find an alternative solution that is simpler.
We want to react a bit more aggressively if we sense that the master is
sending us some corrupted stream. By setting the protocol error we both
ensure that the replica will disconnect, and avoid caching the master so
that a full SYNC will be required. This is protective against
replication bugs.
`clusterStartHandshake` will start hand handshake
and eventually send CLUSTER MEET message, which is strictly prohibited
in the REDIS CLUSTER SPEC.
Only system administrator can initiate CLUSTER MEET message.
Futher, according to the SPEC, rather than IP/PORT pairs, only nodeid
can be trusted.
After adjustMeaningfulReplOffset(), all the other related variable
should be updated, including server.second_replid_offset.
Or the old version redis like 5.0 may receive wrong data from
replication stream, cause redis 5.0 can sync with redis 6.0,
but doesn't know meaningful offset.
Otherwise we run into that:
Backtrace:
src/redis-server 127.0.0.1:21322(logStackTrace+0x45)[0x479035]
src/redis-server 127.0.0.1:21322(sigsegvHandler+0xb9)[0x4797f9]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x11390)[0x7fd373c5e390]
src/redis-server 127.0.0.1:21322(_serverAssert+0x6a)[0x47660a]
src/redis-server 127.0.0.1:21322(freeReplicationBacklog+0x42)[0x451282]
src/redis-server 127.0.0.1:21322[0x4552d4]
src/redis-server 127.0.0.1:21322[0x4c5593]
src/redis-server 127.0.0.1:21322(aeProcessEvents+0x2e6)[0x42e786]
src/redis-server 127.0.0.1:21322(aeMain+0x1d)[0x42eb0d]
src/redis-server 127.0.0.1:21322(main+0x4c5)[0x42b145]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf0)[0x7fd3738a3830]
src/redis-server 127.0.0.1:21322(_start+0x29)[0x42b409]
Since we disconnect all the replicas and free the replication backlog in
certain replication paths, and the code that will free the replication
backlog expects that no replica is connected.
However we still need to free the replicas asynchronously in certain
cases, as documented in the top comment of disconnectSlaves().
Citing from the issue:
btw I suggest we change this fix to something else:
* We revert the fix.
* We add a call that disconnects chained replicas in the place where we trim the replica (that is a master i this case) offset.
This way we can avoid disconnections when there is no trimming of the backlog.
Note that we now want to disconnect replicas asynchronously in
disconnectSlaves(), because it's in general safer now that we can call
it from freeClient(). Otherwise for instance the command:
CLIENT KILL TYPE master
May crash: clientCommand() starts running the linked of of clients,
looking for clients to kill. However it finds the master, kills it
calling freeClient(), but this in turn calls replicationCacheMaster()
that may also call disconnectSlaves() now. So the linked list iterator
of the clientCommand() will no longer be valid.
There's a rare case which leads to stagnation in the defragger, causing
it to keep scanning the keyspace and do nothing (not moving any
allocation), this happens when all the allocator slabs of a certain bin
have the same % utilization, but the slab from which new allocations are
made have a lower utilization.
this commit fixes it by removing the current slab from the overall
average utilization of the bin, and also eliminate any precision loss in
the utilization calculation and move the decision about the defrag to
reside inside jemalloc.
and also add a test that consistently reproduce this issue.
in ACLSetUserCommandBit, when the command bit overflows, no operation
is performed, so no need clear the USER_FLAG_ALLCOMMANDS flag.
in ACLSetUser, when adding subcommand, we don't need to call
ACLGetCommandID ahead since subcommand may be empty.
This was broken in 1a7cd2c: we identified a crash in the CI, what
was happening before the fix should be like that:
1. The client gets in the async free list.
2. However freeClient() gets called again against the same client
which is a master.
3. The client arrived in freeClient() with the CLOSE_ASAP flag set.
4. The master gets cached, but NOT removed from the CLOSE_ASAP linked
list.
5. The master client that was cached was immediately removed since it
was still in the list.
6. Redis accessed a freed cached master.
This is how the crash looked like:
=== REDIS BUG REPORT START: Cut & paste starting from here ===
1092:S 16 May 2020 11:44:09.731 # Redis 999.999.999 crashed by signal: 11
1092:S 16 May 2020 11:44:09.731 # Crashed running the instruction at: 0x447e18
1092:S 16 May 2020 11:44:09.731 # Accessing address: 0xffffffffffffffff
1092:S 16 May 2020 11:44:09.731 # Failed assertion: (:0)
------ STACK TRACE ------
EIP:
src/redis-server 127.0.0.1:21300(readQueryFromClient+0x48)[0x447e18]
And the 0xffff address access likely comes from accessing an SDS that is
set to NULL (we go -1 offset to read the header).
The context is issue #7205: since the introduction of threaded I/O we close
clients asynchronously by default from readQueryFromClient(). So we
should no longer prevent the caching of the master client, to later
PSYNC incrementally, if such flags are set. However we also don't want
the master client to be cached with such flags (would be closed
immediately after being restored). And yet we want a way to understand
if a master was closed because of a protocol error, and in that case
prevent the caching.
This bug was introduced by a recent change in which readQueryFromClient
is using freeClientAsync, and despite the fact that now
freeClientsInAsyncFreeQueue is in beforeSleep, that's not enough since
it's not called during loading in processEventsWhileBlocked.
furthermore, afterSleep was called in that case but beforeSleep wasn't.
This bug also caused slowness sine the level-triggered mode of epoll
kept signaling these connections as readable causing us to keep doing
connRead again and again for ll of these, which keep accumulating.
now both before and after sleep are called, but not all of their actions
are performed during loading, some are only reserved for the main loop.
fixes issue #7215
This is really required only for older OpenSSL versions.
Also, at the moment Redis does not use OpenSSL from multiple threads so
this will only be useful if modules end up doing that.
We want to send pings and pongs at specific intervals, since our packets
also contain information about the configuration of the cluster and are
used for gossip. However since our cluster bus is used in a mixed way
for data (such as Pub/Sub or modules cluster messages) and metadata,
sometimes a very busy channel may delay the reception of pong packets.
So after discussing it in #7216, this commit introduces a new field that
is not exposed in the cluster, is only an internal information about
the last time we received any data from a given node: we use this field
in order to avoid detecting failures, claiming data reception of new
data from the node is a proof of liveness.
This works because this struct is never referenced by its name,
but always by its type.
This prevents a conflict with struct user from <sys/user.h>
when compiling against uclibc.
Signed-off-by: Titouan Christophe <titouan.christophe@railnova.eu>
