RedisGraph crashed when executing read-only query

[MrSrsen]

Hello there.

I am new to Cyper and RedisGraph. I am currently experimenting with graph DB technology on some test data. I really do not know what exactly am I doing but I am pretty sure that DB should not crash when executing read-only query.

I was executing this query trough RedisInsight:
MATCH (roots:broker) WHERE NOT ()<-[:supervising]-(:broker) WITH roots MATCH (roots)-[s:supervising]->(b:broker) RETURN roots, b, s

And I got:

=== REDIS BUG REPORT START: Cut & paste starting from here ===
1:M 30 Apr 2020 13:37:55.336 # Redis 5.0.8 crashed by signal: 11
1:M 30 Apr 2020 13:37:55.336 # Crashed running the instruction at: 0x7fdfcf305769
1:M 30 Apr 2020 13:37:55.336 # Accessing address: (nil)
1:M 30 Apr 2020 13:37:55.336 # Failed assertion: <no assertion failed> (<no file>:0)

------ STACK TRACE ------
EIP:
/usr/lib/redis/modules/redisgraph.so(OpBase_CloneRecord+0x9)[0x7fdfcf305769]

Backtrace:
redis-server *:6379(logStackTrace+0x32)[0x55b7cdd37592]
redis-server *:6379(sigsegvHandler+0x9e)[0x55b7cdd37c6e]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12730)[0x7fdfd046f730]
/usr/lib/redis/modules/redisgraph.so(OpBase_CloneRecord+0x9)[0x7fdfcf305769]
/usr/lib/redis/modules/redisgraph.so(+0x1cc875)[0x7fdfcf307875]
/usr/lib/redis/modules/redisgraph.so(+0x1c8973)[0x7fdfcf303973]
/usr/lib/redis/modules/redisgraph.so(+0x1c40ed)[0x7fdfcf2ff0ed]
/usr/lib/redis/modules/redisgraph.so(+0x1c4afc)[0x7fdfcf2ffafc]
/usr/lib/redis/modules/redisgraph.so(+0x1c8973)[0x7fdfcf303973]
/usr/lib/redis/modules/redisgraph.so(+0x1c4afc)[0x7fdfcf2ffafc]
/usr/lib/redis/modules/redisgraph.so(+0x1cbb9c)[0x7fdfcf306b9c]
/usr/lib/redis/modules/redisgraph.so(ExecutionPlan_Execute+0x58)[0x7fdfcf2fc178]
/usr/lib/redis/modules/redisgraph.so(Graph_Query+0x351)[0x7fdfcf2f6691]
/usr/lib/redis/modules/redisgraph.so(+0x1ebd1d)[0x7fdfcf326d1d]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x7fa3)[0x7fdfd0464fa3]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x3f)[0x7fdfd03954cf]

------ INFO OUTPUT ------
# Server
redis_version:5.0.8
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:ce75a617c591114f
redis_mode:standalone
os:Linux 5.2.14-050214-generic x86_64
arch_bits:64
multiplexing_api:epoll
atomicvar_api:atomic-builtin
gcc_version:8.3.0
process_id:1
run_id:2799cd5dbd1bc1a8b45c7d713c06f5637f5fdef2
tcp_port:6379
uptime_in_seconds:10020
uptime_in_days:0
hz:10
configured_hz:10
lru_clock:11195571
executable:/data/redis-server
config_file:

# Clients
connected_clients:2
client_recent_max_input_buffer:2
client_recent_max_output_buffer:0
blocked_clients:1

# Memory
used_memory:6668744
used_memory_human:6.36M
used_memory_rss:10191265792
used_memory_rss_human:9.49G
used_memory_peak:9454603984
used_memory_peak_human:8.81G
used_memory_peak_perc:0.07%
used_memory_overhead:858620
used_memory_startup:824704
used_memory_dataset:5886868
used_memory_dataset_perc:99.43%
allocator_allocated:9664760
allocator_active:14667776
allocator_resident:17525235712
total_system_memory:16831561728
total_system_memory_human:15.68G
used_memory_lua:37888
used_memory_lua_human:37.00K
used_memory_scripts:0
used_memory_scripts_human:0B
number_of_cached_scripts:0
maxmemory:0
maxmemory_human:0B
maxmemory_policy:noeviction
allocator_frag_ratio:1.52
allocator_frag_bytes:5003016
allocator_rss_ratio:1194.81
allocator_rss_bytes:17510567936
rss_overhead_ratio:0.58
rss_overhead_bytes:-7333969920
mem_fragmentation_ratio:1501.94
mem_fragmentation_bytes:10184480376
mem_not_counted_for_evict:0
mem_replication_backlog:0
mem_clients_slaves:0
mem_clients_normal:33844
mem_aof_buffer:0
mem_allocator:jemalloc-5.1.0
active_defrag_running:0
lazyfree_pending_objects:0

# Persistence
loading:0
rdb_changes_since_last_save:11628
rdb_bgsave_in_progress:0
rdb_last_save_time:1588243855
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:-1
rdb_current_bgsave_time_sec:-1
rdb_last_cow_size:0
aof_enabled:0
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:-1
aof_current_rewrite_time_sec:-1
aof_last_bgrewrite_status:ok
aof_last_write_status:ok
aof_last_cow_size:0

# Stats
total_connections_received:32
total_commands_processed:12903
instantaneous_ops_per_sec:1
total_net_input_bytes:3562896
total_net_output_bytes:13603879
instantaneous_input_kbps:0.15
instantaneous_output_kbps:0.05
rejected_connections:0
sync_full:0
sync_partial_ok:0
sync_partial_err:0
expired_keys:0
expired_stale_perc:0.00
expired_time_cap_reached_count:0
evicted_keys:0
keyspace_hits:23879
keyspace_misses:1
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:0
migrate_cached_sockets:0
slave_expires_tracked_keys:0
active_defrag_hits:0
active_defrag_misses:0
active_defrag_key_hits:0
active_defrag_key_misses:0

# Replication
role:master
connected_slaves:0
master_replid:fdb3959e973f809e5a935083864e9deca920a9b8
master_replid2:0000000000000000000000000000000000000000
master_repl_offset:0
second_repl_offset:-1
repl_backlog_active:0
repl_backlog_size:1048576
repl_backlog_first_byte_offset:0
repl_backlog_histlen:0

# CPU
used_cpu_sys:107.863217
used_cpu_user:1467.656622
used_cpu_sys_children:0.004884
used_cpu_user_children:0.002061

# Commandstats
cmdstat_type:calls=1,usec=1,usec_per_call=1.00
cmdstat_scan:calls=1,usec=10,usec_per_call=10.00
cmdstat_client:calls=7,usec=14,usec_per_call=2.00
cmdstat_module:calls=642,usec=2268,usec_per_call=3.53
cmdstat_graph.QUERY:calls=12251,usec=321557,usec_per_call=26.25
cmdstat_info:calls=1,usec=61,usec_per_call=61.00

# Cluster
cluster_enabled:0

# Keyspace
db0:keys=1,expires=0,avg_ttl=0

------ CLIENT LIST OUTPUT ------
id=24215 addr=172.27.0.3:47806 fd=8 name= age=752 idle=268 flags=N db=0 sub=0 psub=0 multi=-1 qbuf=0 qbuf-free=0 obl=0 oll=0 omem=0 events=r cmd=graph.QUERY
id=24230 addr=172.27.0.3:49480 fd=9 name= age=573 idle=0 flags=b db=0 sub=0 psub=0 multi=-1 qbuf=0 qbuf-free=0 obl=0 oll=0 omem=0 events=r cmd=graph.QUERY

------ REGISTERS ------
1:M 30 Apr 2020 13:37:55.357 # 
RAX:0000000000000000 RBX:00007fdfc5c30480
RCX:0000000000000a85 RDX:0000000000000000
RDI:0000000000000000 RSI:0000000000000001
RBP:0000000000000000 RSP:00007fdfcd9352f0
R8 :0000000000000000 R9 :0000000000000007
R10:00007fdfcd935fd0 R11:00007fdfcd935fd0
R12:00007fdfcd935318 R13:00007fdfcd935317
R14:00007fdfc5c30520 R15:0000000000000000
RIP:00007fdfcf305769 EFL:0000000000010206
CSGSFS:002b000000000033
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352ff) -> ffffffffffffffff
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352fe) -> ffffffffffffffff
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352fd) -> 01007fdfcf2f8b46
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352fc) -> 00007fdfcd935420
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352fb) -> 00007fdfcf303973
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352fa) -> 00007fdfcd93535f
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f9) -> 00007fdfcd935368
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f8) -> 00007fdfcd935360
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f7) -> 00007fdfc5c30480
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f6) -> 00007fdfcfe17c00
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f5) -> 0000000000000000
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f4) -> 00007fdfc5d44c28
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f3) -> 00007fdfcf307875
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f2) -> 00007fdfc5c30480
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f1) -> 00007fdfc5c30480
1:M 30 Apr 2020 13:37:55.357 # (00007fdfcd9352f0) -> 00007fdfc5c30480

------ FAST MEMORY TEST ------
1:M 30 Apr 2020 13:37:55.362 # Bio thread for job type #0 terminated
1:M 30 Apr 2020 13:37:55.362 # Bio thread for job type #1 terminated
1:M 30 Apr 2020 13:37:55.362 # Bio thread for job type #2 terminated
*** Preparing to test memory region 55b7cde65000 (2248704 bytes)
*** Preparing to test memory region 55b7cea4f000 (135168 bytes)
*** Preparing to test memory region 7fd9c5800000 (6627000320 bytes)
*** Preparing to test memory region 7fdb50900000 (6305087488 bytes)
*** Preparing to test memory region 7fdcc8700000 (7590641664 bytes)
*** Preparing to test memory region 7fde8cf00000 (1831862272 bytes)
*** Preparing to test memory region 7fdefa300000 (2515673088 bytes)
*** Preparing to test memory region 7fdf94000000 (7905280 bytes)
*** Preparing to test memory region 7fdf98000000 (3186688 bytes)
*** Preparing to test memory region 7fdf9c000000 (3186688 bytes)
*** Preparing to test memory region 7fdfa0000000 (3186688 bytes)
*** Preparing to test memory region 7fdfa4000000 (2461696 bytes)
*** Preparing to test memory region 7fdfa8000000 (6934528 bytes)
*** Preparing to test memory region 7fdfac000000 (3186688 bytes)
*** Preparing to test memory region 7fdfb0000000 (2457600 bytes)
*** Preparing to test memory region 7fdfb4000000 (3407872 bytes)
*** Preparing to test memory region 7fdfb8000000 (2187264 bytes)
*** Preparing to test memory region 7fdfbc180000 (71766016 bytes)
*** Preparing to test memory region 7fdfc4000000 (48234496 bytes)
*** Preparing to test memory region 7fdfc6f80000 (6815744 bytes)
*** Preparing to test memory region 7fdfc76ac000 (2621440 bytes)
*** Preparing to test memory region 7fdfc792d000 (8388608 bytes)
*** Preparing to test memory region 7fdfc812e000 (8388608 bytes)
*** Preparing to test memory region 7fdfc892f000 (8388608 bytes)
*** Preparing to test memory region 7fdfc9130000 (8388608 bytes)
*** Preparing to test memory region 7fdfc9931000 (8388608 bytes)
*** Preparing to test memory region 7fdfca132000 (8388608 bytes)
*** Preparing to test memory region 7fdfca933000 (8388608 bytes)
*** Preparing to test memory region 7fdfcb134000 (8388608 bytes)
*** Preparing to test memory region 7fdfcb935000 (8388608 bytes)
*** Preparing to test memory region 7fdfcc136000 (8388608 bytes)
*** Preparing to test memory region 7fdfcc937000 (8388608 bytes)
*** Preparing to test memory region 7fdfcd138000 (8388608 bytes)
*** Preparing to test memory region 7fdfcd939000 (8388608 bytes)
*** Preparing to test memory region 7fdfce13a000 (8388608 bytes)
*** Preparing to test memory region 7fdfce93b000 (8388608 bytes)
*** Preparing to test memory region 7fdfcf9fd000 (12288 bytes)
*** Preparing to test memory region 7fdfcfa00000 (8388608 bytes)
*** Preparing to test memory region 7fdfd0296000 (24576 bytes)
*** Preparing to test memory region 7fdfd0459000 (16384 bytes)
*** Preparing to test memory region 7fdfd047a000 (16384 bytes)
*** Preparing to test memory region 7fdfd0610000 (8192 bytes)
*** Preparing to test memory region 7fdfd063d000 (4096 bytes)
.redis-server: ../nptl/pthread_mutex_lock.c:433: __pthread_mutex_lock_full: Assertion `INTERNAL_SYSCALL_ERRNO (e, __err) != ESRCH || !robust' failed.
RGT-REDIS exited with code 139

RedisInsight and also Redis are running inside docker containers.

I hope this will help you somehow.

[jeffreylovitz]

Thanks for the report, @MrSrsen!

That's definitely a bug, this should not crash. We'll try to address this soon!

The issue with your query is in:
WHERE NOT ()<-[:supervising]-(:broker)

This construction is legal, but a bit bizarre - path filters like this usually act on at least one bound variable, such as the alias roots.

[MrSrsen]

Yeah I didn't see that. Thanks, now it's working! :D

[MrSrsen]

Aaaand it crashed again.

@jeffreylovitz Should I create new issue or is this the same bug?

Query: MATCH rel = (root:broker {broker_id: "124"})<-[:supervising *]-(sup:broker) WHERE rel.modul_id = 3 RETURN rel

Result:

=== REDIS BUG REPORT START: Cut & paste starting from here ===
1:M 30 Apr 2020 15:19:57.287 # Redis 5.0.8 crashed by signal: 11
1:M 30 Apr 2020 15:19:57.287 # Crashed running the instruction at: 0x7ffae4810611
1:M 30 Apr 2020 15:19:57.287 # Accessing address: (nil)
1:M 30 Apr 2020 15:19:57.287 # Failed assertion: <no assertion failed> (<no file>:0)

(details moved to another issue)

I really should read manual or book about Cypher because otherwise this will be loooong path to desired result :D

---

Moved to: #1084

[jeffreylovitz]

Ick, sorry!

This is a different bug, so you can open a new issue.

The problem in this case is that rel is a path, so attempting a property access on it like rel.modul_id = 3 should cause an error to be emitted.

We have a lot of assertions that should really be replaced with user-facing errors, as you're observing! It's something we should address broadly, but a lot of the cases are fairly unique, so reports like these are really helpful 🙂 .

[jeffreylovitz]

Hey @MrSrsen,

This bug should be fixed now! Thanks again for the report.