This use-after-free can be reproduced with distributed queries.
Also note, that this is not sumMappedArray() and friends (that
previously called sumMap()) but Map combinator.
You will find ASan report in details.
<details>
READ of size 8 at 0x62d00012d218 thread T186 (QueryPipelineEx)
2022.07.03 05:09:40.000234 [ 31956 ] {} <Trace> AsynchronousMetrics: MemoryTracking: was 1.23 GiB, peak 1.23 GiB, will set to 1.25 GiB (RSS), difference: 19.51 MiB
2022.07.03 05:09:41.000137 [ 31956 ] {} <Trace> AsynchronousMetrics: MemoryTracking: was 1.25 GiB, peak 1.25 GiB, will set to 1.26 GiB (RSS), difference: 3.76 MiB
#0 0x1233a0d8 in DB::AggregateFunctionSumData<>::get() const build_docker/../src/AggregateFunctions/AggregateFunctionSum.h:245:16
#1 0x1233a0d8 in DB::AggregateFunctionSum<>::insertResultInto(char*, DB::IColumn&, DB::Arena*) const build_docker/../src/AggregateFunctions/AggregateFunctionSum.h:536:70
#2 0x1470f910 in DB::AggregateFunctionMap<char8_t>::insertResultInto() const build_docker/../src/AggregateFunctions/AggregateFunctionMap.h:236:26
#3 0x147110ce in DB::IAggregateFunctionHelper<>::insertResultIntoBatch() const build_docker/../src/AggregateFunctions/IAggregateFunction.h:618:53
#4 0x2c4269d7 in void DB::Aggregator::convertToBlockImplFinal<>() const build_docker/../src/Interpreters/Aggregator.cpp:1878:49
#5 0x2c403b9f in void DB::Aggregator::convertToBlockImpl<>() const build_docker/../src/Interpreters/Aggregator.cpp:1714:13
#6 0x2be09b53 in DB::Aggregator::prepareBlockAndFillSingleLevel() const::$_2::operator()() const build_docker/../src/Interpreters/Aggregator.cpp:2144:9
#7 0x2be09b53 in DB::Block DB::Aggregator::prepareBlockAndFill<>() const build_docker/../src/Interpreters/Aggregator.cpp:2000:5
#8 0x2be09b53 in DB::Aggregator::prepareBlockAndFillSingleLevel() const build_docker/../src/Interpreters/Aggregator.cpp:2150:12
#9 0x2be37de3 in DB::Aggregator::mergeBlocks() build_docker/../src/Interpreters/Aggregator.cpp:3032:17
#10 0x308c27f8 in DB::MergingAggregatedBucketTransform::transform() build_docker/../src/Processors/Transforms/MergingAggregatedMemoryEfficientTransform.cpp:360:37
0x62d00012d218 is located 3608 bytes inside of 32768-byte region [0x62d00012c400,0x62d000134400)
freed by thread T186 (QueryPipelineEx) here:
#0 0xd701312 in free (/work1/azat/tmp/upstream/clickhouse-asan+0xd701312) (BuildId: b7977aef37e9f720)
...
#8 0x2e3c22eb in DB::ColumnAggregateFunction::~ColumnAggregateFunction() build_docker/../src/Columns/ColumnAggregateFunction.cpp:89:1
...
#18 0xd9fcdd4 in std::__1::vector<DB::ColumnWithTypeAndName, std::__1::allocator<DB::ColumnWithTypeAndName> >::~vector() build_docker/../contrib/libcxx/include/vector:401:9
#19 0x2be373f4 in DB::Aggregator::mergeBlocks() build_docker/../contrib/libcxx/include/__memory/unique_ptr.h
#20 0x308c27f8 in DB::MergingAggregatedBucketTransform::transform() build_docker/../src/Processors/Transforms/MergingAggregatedMemoryEfficientTransform.cpp:360:37
previously allocated by thread T186 (QueryPipelineEx) here:
#0 0xd7015be in malloc (/work1/azat/tmp/upstream/clickhouse-asan+0xd7015be) (BuildId: b7977aef37e9f720)
#1 0xd85190a in Allocator<false, false>::allocNoTrack(unsigned long, unsigned long) build_docker/../src/Common/Allocator.h:227:27
#2 0xd988d45 in Allocator<false, false>::alloc(unsigned long, unsigned long) build_docker/../src/Common/Allocator.h:96:16
#3 0xd988d45 in DB::Arena::MemoryChunk::MemoryChunk(unsigned long, DB::Arena::MemoryChunk*) build_docker/../src/Common/Arena.h:54:64
#4 0xd98904b in DB::Arena::addMemoryChunk(unsigned long) build_docker/../src/Common/Arena.h:122:20
#5 0xec9542c in DB::Arena::alignedAlloc(unsigned long, unsigned long) build_docker/../src/Common/Arena.h:171:13
#6 0x1470f123 in DB::AggregateFunctionMap<char8_t>::deserialize() const build_docker/../src/AggregateFunctions/AggregateFunctionMap.h:205:35
</details>
P.S. Thanks to @den-crane for the reproducer.
Fixes: #35359 (cc @den-crane @dongxiao-yang)
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
It can be useful to match versions, since in some tables
(system.trace_log) there is only revision column.
P.S. came to this when was digging into stress reports from CI.
P.P.S. case insensitive by analogy with version().
Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
SQL functions countSubstrings(), countSubstringsCaseInsensitive(),
countSubstringsUTF8(), position(), positionCaseInsensitive(),
positionUTF8() with non-const pattern argument use fallback sorters
LibCASCIICaseSensitiveStringSearcher and LibCASCIICaseInsensitiveStringSearcher
which call ::strstr(), resp. ::strcasestr(). These functions assume that
the haystack is 0-terminated and they even document that. However, the
callers did not check if the haystack contains 0-byte (perhaps because
its sort of expensive). As a consequence, if the haystack contained a
zero byte in it's payload, matches behind this zero byte were ignored.
create table t (id UInt32, pattern String) engine = MergeTree() order by id;
insert into t values (1, 'x');
select countSubstrings('aaaxxxaa\0xxx', pattern) from t;
We returned 3 before this commit, now we return 6
