Re: Re: Add support for specifying tables in pg_createsubscriber. - Mailing list pgsql-hackers

On Wed, Dec 3, 2025 at 4:47 PM tianbing <tian_bing_0531@163.com> wrote:
>
> Hi， Peter，
> I have reviewed the v21 patch and noticed that there seems to be a memory leak.
>
> +static bool
> +check_publication_exists(PGconn *conn, const char *pubname, const char *dbname)
> +{
> + PGresult *res;
> + bool exists;
> + char *query;
> +
> + query = psprintf("SELECT 1 FROM pg_publication WHERE pubname = %s",
> + PQescapeLiteral(conn, pubname, strlen(pubname)));
> + res = PQexec(conn, query);
> +
> + if (PQresultStatus(res) != PGRES_TUPLES_OK)
> + pg_fatal("could not check for publication \"%s\" in database \"%s\": %s",
> + pubname, dbname, PQerrorMessage(conn));
> +
> + exists = (PQntuples(res) == 1);
> +
> + PQclear(res);
> + pg_free(query);
> + return exists;
> +}
>
> The PQescapeLiteral() function through malloc to allocate memmory，and should be free by PQfreemem。
>
> I suggest making the following modifications：
>
> + char *pub = PQescapeLiteral(conn, pubname, strlen(pubname);
> + query = psprintf("SELECT 1 FROM pg_publication WHERE pubname = %s", pub);
> ......
> + PQfreemem(pub);
>

Fixed in v22.

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Kind Regards,
Peter Smith.
Fujitsu Australia