pgsql: Avoid memory leak on error while parsing pg_stat_statements dump

Avoid memory leak on error while parsing pg_stat_statements dump file

By using palloc() instead of raw malloc().

Reported-by: Gaurav Singh <gaurav.singh@yugabyte.com>
Reviewed-by: Lukas Fittl <lukas@fittl.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://www.postgresql.org/message-id/CAEcQ1bYR9s4eQLFDjzzJHU8fj-MTbmRpW-9J-r2gsCn+HEsynw@mail.gmail.com
Backpatch-through: 14

Branch
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REL_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/351e59f344b57bb6958bdf455bf5069d6e52a922

Modified Files
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contrib/pg_stat_statements/pg_stat_statements.c | 22 +++++++++++++---------
1 file changed, 13 insertions(+), 9 deletions(-)