pgsql: pg_freespacemap: Fix declaration of pg_freespace(regclass)

pg_freespacemap: Fix declaration of pg_freespace(regclass)

This function called generate_series() without enforcing its input
argument types, making possible for an attacker to catch this call, by
defining for example a generate_series(int,bigint).

The internals of pg_freespace(regclass) are changed to force the use of
bigint for the inputs of generate_series(). A more consistent style is
applied for all its hardcoded values, while on it.

Issue introduced in 3f323eba89fb.

Reported-by: Noah Misch
Reviewed-by: Noah Misch
Discussion: https://postgr.es/m/20250106190428.ec.nmisch@google.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e0c3d5122e6a4114af3092b7938c9b43d619e62c

Modified Files
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contrib/pg_freespacemap/pg_freespacemap--1.2--1.3.sql | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)