pgsql: Add missing error check in pgcrypto/crypt-md5.c.

Add missing error check in pgcrypto/crypt-md5.c.

In theory, the second px_find_digest call in px_crypt_md5 could fail
even though the first one succeeded, since resource allocation is
required. Don't skip testing for a failure. (If one did happen,
the likely result would be a crash rather than clean recovery from
an OOM failure.)

The code's been like this all along, so back-patch to all supported
branches.

Daniel Gustafsson

Discussion: /messages/by-id/AA8D6FE9-4AB2-41B4-98CB-AE64BA668C03@yesql.se

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/7004ce75897e008442673289b7c71af2832200f8

Modified Files
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contrib/pgcrypto/crypt-md5.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)