Fix sanitizer issues in wal_archiving

ci_scripts/suppressions/lsan.supp

@@ -55,3 +55,7 @@ leak:dumpDumpableObject
 #pg_rewind
 leak:decide_file_actions
 leak:GenerateRecoveryConfig
+
+# Returns strdup'd string which never gets freed in frontend tools. Trying to 
+# free it leads to comiler complains that it discards 'const' qualifier.
+leak:get_progname

contrib/pg_tde/src/access/pg_tde_tdemap.c

@@ -1018,6 +1018,9 @@ pg_tde_read_last_wal_key(void)
 	/* No keys */
 	if (fsize == TDE_FILE_HEADER_SIZE)
 	{
+#ifdef FRONTEND
+		pfree(principal_key);
+#endif
 		LWLockRelease(lock_pk);
 		CloseTransientFile(fd);
 		return NULL;
@@ -1027,6 +1030,9 @@ pg_tde_read_last_wal_key(void)
 	pg_tde_read_one_map_entry2(fd, file_idx, &map_entry, rlocator.dbOid);
 
 	rel_key_data = tde_decrypt_rel_key(principal_key, &map_entry);
+#ifdef FRONTEND
+	pfree(principal_key);
+#endif
 	LWLockRelease(lock_pk);
 	CloseTransientFile(fd);
 

contrib/pg_tde/src/bin/pg_tde_archive_decrypt.c

@@ -208,7 +208,13 @@ main(int argc, char *argv[])
 	if (r != child)
 		pg_fatal("child %d died, expected %d", (int) r, (int) child);
 	if (status != 0)
-		pg_fatal("%s", wait_result_to_str(status));
+	{
+		char	   *reason = wait_result_to_str(status);
+
+		pg_fatal("%s", reason);
+		/* keep lsan happy */
+		free(reason);
+	}
 
 	if (issegment)
 	{

contrib/pg_tde/src/bin/pg_tde_restore_encrypt.c

@@ -202,7 +202,13 @@ main(int argc, char *argv[])
 	if (r != child)
 		pg_fatal("child %d died, expected %d", (int) r, (int) child);
 	if (status != 0)
-		pg_fatal("%s", wait_result_to_str(status));
+	{
+		char	   *reason = wait_result_to_str(status);
+
+		pg_fatal("%s", reason);
+		/* keep lsan happy */
+		free(reason);
+	}
 
 	if (issegment)
 	{