ERROR: invalid memory alloc request size 18446744073709551613

Hello all,

When using Postgres 9.6.15 on "CentOS Linux release 7.5.1804 (Core)" on
Intel x86_64 I noticed "invalid memory alloc request size" error at
PostgreSQL logs.
This is the postgresq.log file's fragment of log where the error was found.

2020-06-22 00:29:18 BRT [16987]: [1-1] db=bxs,user=postgres ERRO: invalid
memory alloc request size 18446744073709551613
2020-06-22 00:29:18 BRT [16987]: [2-1] db=bxs,user=postgres COMANDO: COPY
public.cham_chamada....

PostgreSQL was installed using official PGDG repository through yum.
This is the list of postgresql.conf settings used in the cluster.

listen_addresses = '*'
log_destination = 'stderr'
logging_collector = on
log_directory = 'pg_log'
log_filename = 'postgresql-%a.log'
log_truncate_on_rotation = on
log_rotation_age = 1d
log_rotation_size = 0
autovacuum = off
datestyle = 'iso, mdy'
lc_messages = 'pt_BR'
lc_monetary = 'pt_BR'
lc_numeric = 'pt_BR'
lc_time = 'pt_BR'
default_text_search_config = 'pg_catalog.portuguese'
max_connections=150
shared_buffers=2GB
effective_cache_size=4GB
work_mem=13981kB
maintenance_work_mem=256MB
log_min_duration_statement = 300000
log_line_prefix = '%t [%p]: [%l-1] db=%d,user=%u '
log_lock_waits = on
timezone='America/Sao_paulo'
log_timezone = 'Brazil/East'
min_wal_size = 1GB
max_wal_size = 2GB

Looking at previous list's messages I've found this could be a data
corruption issue and I've followed the recommended procedures.
But even removing the corrupted records, doing a vacuum full and
re-indexing the table the problem keep going recurrently.
So I would like some guidance to find the root cause of the table
corruption on the database.
Any help would be appreciated.

Thanks in advance,
Flaris Feller.

--
Flaris Roland Feller
https://www.linkedin.com/in/flarisfeller
flaris(dot)feller(at)gmail(dot)com