### ClickHouse release v21.1.8.30-stable FIXME as compared to v21.1.7.1-stable
#### Bug Fix
* Backported in [#21205](https://github.com/ClickHouse/ClickHouse/issues/21205): Fix the metadata leak when the Replicated*MergeTree with custom (non default) ZooKeeper cluster is dropped. [#21119](https://github.com/ClickHouse/ClickHouse/pull/21119) ([fastio](https://github.com/fastio)).
* Backported in [#21161](https://github.com/ClickHouse/ClickHouse/issues/21161): Fix `input_format_null_as_default` take effective when types are nullable. This fixes [#21116](https://github.com/ClickHouse/ClickHouse/issues/21116) . [#21121](https://github.com/ClickHouse/ClickHouse/pull/21121) ([Amos Bird](https://github.com/amosbird)).
* Backported in [#21926](https://github.com/ClickHouse/ClickHouse/issues/21926): Fix Avro format parsing for Kafka. Fixes [#21437](https://github.com/ClickHouse/ClickHouse/issues/21437). [#21438](https://github.com/ClickHouse/ClickHouse/pull/21438) ([Ilya Golshtein](https://github.com/ilejn)).
* Backported in [#22189](https://github.com/ClickHouse/ClickHouse/issues/22189): Fixed race on SSL object inside SecureSocket in Poco. [#21456](https://github.com/ClickHouse/ClickHouse/pull/21456) ([Nikita Mikhaylov](https://github.com/nikitamikhaylov)).
* Backported in [#22317](https://github.com/ClickHouse/ClickHouse/issues/22317): Remove unknown columns from joined table in where for queries to external database engines (MySQL, PostgreSQL). close [#14614](https://github.com/ClickHouse/ClickHouse/issues/14614), close [#19288](https://github.com/ClickHouse/ClickHouse/issues/19288) (dup), close [#19645](https://github.com/ClickHouse/ClickHouse/issues/19645) (dup). [#21640](https://github.com/ClickHouse/ClickHouse/pull/21640) ([Vladimir C](https://github.com/vdimir)).
* Backported in [#21797](https://github.com/ClickHouse/ClickHouse/issues/21797): Fix distributed requests cancellation (for example simple select from multiple shards with limit, i.e. `select * from remote('127.{2,3}', system.numbers) limit 100`) with `async_socket_for_remote=1`. [#21643](https://github.com/ClickHouse/ClickHouse/pull/21643) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#22287](https://github.com/ClickHouse/ClickHouse/issues/22287): Start accepting connections after DDLWorker and dictionaries initialization. [#21676](https://github.com/ClickHouse/ClickHouse/pull/21676) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#21810](https://github.com/ClickHouse/ClickHouse/issues/21810): Fix bug for ReplicatedMerge table engines when `ALTER MODIFY COLUMN` query doesn't change the type of decimal column if its size (32 bit or 64 bit) doesn't change. [#21728](https://github.com/ClickHouse/ClickHouse/pull/21728) ([alesapin](https://github.com/alesapin)).
* Backported in [#21880](https://github.com/ClickHouse/ClickHouse/issues/21880): Fix possible crashes in aggregate functions with combinator Distinct, while using two-level aggregation. This is a follow-up fix of https://github.com/ClickHouse/ClickHouse/pull/18365 . Can only reproduced in production env. No test case available yet. cc @CurtizJ. [#21818](https://github.com/ClickHouse/ClickHouse/pull/21818) ([Amos Bird](https://github.com/amosbird)).
* Backported in [#22052](https://github.com/ClickHouse/ClickHouse/issues/22052): Fix deadlock in first catboost model execution. Closes [#13832](https://github.com/ClickHouse/ClickHouse/issues/13832). [#21844](https://github.com/ClickHouse/ClickHouse/pull/21844) ([Kruglov Pavel](https://github.com/Avogar)).
* Backported in [#21981](https://github.com/ClickHouse/ClickHouse/issues/21981): Reverted [#15454](https://github.com/ClickHouse/ClickHouse/issues/15454) that may cause significant increase in memory usage while loading external dictionaries of hashed type. This closes [#21935](https://github.com/ClickHouse/ClickHouse/issues/21935). [#21948](https://github.com/ClickHouse/ClickHouse/pull/21948) ([Maksim Kita](https://github.com/kitaisreal)).
* Backported in [#22465](https://github.com/ClickHouse/ClickHouse/issues/22465): In rare case, merge for `CollapsingMergeTree` may create granule with `index_granularity + 1` rows. Because of this, internal check, added in [#18928](https://github.com/ClickHouse/ClickHouse/issues/18928) (affects 21.2 and 21.3), may fail with error `Incomplete granules are not allowed while blocks are granules size`. This error did not allow parts to merge. [#21976](https://github.com/ClickHouse/ClickHouse/pull/21976) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
* Backported in [#22149](https://github.com/ClickHouse/ClickHouse/issues/22149): The function `decrypt` was lacking a check for the minimal size of data encrypted in AEAD mode. This closes [#21897](https://github.com/ClickHouse/ClickHouse/issues/21897). [#22064](https://github.com/ClickHouse/ClickHouse/pull/22064) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
* Backported in [#22283](https://github.com/ClickHouse/ClickHouse/issues/22283): Docker entrypoint: avoid chown of `.` in case when `LOG_PATH` is empty. Closes [#22100](https://github.com/ClickHouse/ClickHouse/issues/22100). [#22102](https://github.com/ClickHouse/ClickHouse/pull/22102) ([filimonov](https://github.com/filimonov)).
* Backported in [#22280](https://github.com/ClickHouse/ClickHouse/issues/22280): Fix waiting for `OPTIMIZE` and `ALTER` queries for `ReplicatedMergeTree` table engines. Now the query will not hang when the table was detached or restarted. [#22118](https://github.com/ClickHouse/ClickHouse/pull/22118) ([alesapin](https://github.com/alesapin)).
* Backported in [#22501](https://github.com/ClickHouse/ClickHouse/issues/22501): Fix query cancellation with `use_hedged_requests=0` and `async_socket_for_remote=1`. [#22183](https://github.com/ClickHouse/ClickHouse/pull/22183) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#22368](https://github.com/ClickHouse/ClickHouse/issues/22368): Now clickhouse will not throw `LOGICAL_ERROR` exception when we try to mutate the already covered part. Fixes [#22013](https://github.com/ClickHouse/ClickHouse/issues/22013). [#22291](https://github.com/ClickHouse/ClickHouse/pull/22291) ([alesapin](https://github.com/alesapin)).
* Backported in [#22533](https://github.com/ClickHouse/ClickHouse/issues/22533): Buffer overflow (on read) was possible in `tokenbf_v1` full text index. The excessive bytes are not used but the read operation may lead to crash in rare cases. This closes [#19233](https://github.com/ClickHouse/ClickHouse/issues/19233). [#22421](https://github.com/ClickHouse/ClickHouse/pull/22421) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
* Backported in [#22462](https://github.com/ClickHouse/ClickHouse/issues/22462): Add (missing) memory accounting in parallel parsing routines. In previous versions OOM was possible when the resultset contains very large blocks of data. This closes [#22008](https://github.com/ClickHouse/ClickHouse/issues/22008). [#22425](https://github.com/ClickHouse/ClickHouse/pull/22425) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
* Backported in [#22555](https://github.com/ClickHouse/ClickHouse/issues/22555): Fix bug in partial merge join with `LowCardinality`. Close [#22386](https://github.com/ClickHouse/ClickHouse/issues/22386), close [#22388](https://github.com/ClickHouse/ClickHouse/issues/22388). [#22510](https://github.com/ClickHouse/ClickHouse/pull/22510) ([Vladimir C](https://github.com/vdimir)).
* Backported in [#22608](https://github.com/ClickHouse/ClickHouse/issues/22608): Fix deserialization of empty string without newline at end of TSV format. This closes [#20244](https://github.com/ClickHouse/ClickHouse/issues/20244). Possible workaround without version update: set `input_format_null_as_default` to zero. It was zero in old versions. [#22527](https://github.com/ClickHouse/ClickHouse/pull/22527) ([Alexey Milovidov](https://github.com/alexey-milovidov)).
* Backported in [#22578](https://github.com/ClickHouse/ClickHouse/issues/22578): Fix UB by unlocking the rwlock of the TinyLog from the same thread. [#22560](https://github.com/ClickHouse/ClickHouse/pull/22560) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#22650](https://github.com/ClickHouse/ClickHouse/issues/22650): Avoid UB in *Log engines for rwlock unlock due to unlock from another thread. [#22583](https://github.com/ClickHouse/ClickHouse/pull/22583) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#22700](https://github.com/ClickHouse/ClickHouse/issues/22700): Fix wait for mutations on several replicas for ReplicatedMergeTree table engines. Previously, mutation/alter query may finish before mutation actually executed on other replicas. [#22669](https://github.com/ClickHouse/ClickHouse/pull/22669) ([alesapin](https://github.com/alesapin)).
* Backported in [#22739](https://github.com/ClickHouse/ClickHouse/issues/22739): Fix possible hangs in zk requests in case of OOM exception. Fixes [#22438](https://github.com/ClickHouse/ClickHouse/issues/22438). [#22684](https://github.com/ClickHouse/ClickHouse/pull/22684) ([Nikolai Kochetov](https://github.com/KochetovNicolai)).
* LRUCache fix exception unsafe element insertion [#21891](https://github.com/ClickHouse/ClickHouse/pull/21891) ([Maksim Kita](https://github.com/kitaisreal)).
* Mannual backport of [#21429](https://github.com/ClickHouse/ClickHouse/issues/21429) in 21.1 [#22506](https://github.com/ClickHouse/ClickHouse/pull/22506) ([Kruglov Pavel](https://github.com/Avogar)).
