net: dsa: sja1105: Use struct_size() in kzalloc()

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

This code was detected with the help of Coccinelle and, audited and
fixed manually.

Addresses-KSPP-ID: https://github.com/KSPP/linux/issues/83
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/sja1105/sja1105_tas.c b/drivers/net/dsa/sja1105/sja1105_tas.c
index 3aa1a8b..31d8acf 100644 (file)
--- a/drivers/net/dsa/sja1105/sja1105_tas.c
+++ b/drivers/net/dsa/sja1105/sja1105_tas.c
@@ -475,8 +475,7 @@ bool sja1105_gating_check_conflicts(struct sja1105_private *priv, int port,
        if (list_empty(&gating_cfg->entries))
                return false;
 
-       dummy = kzalloc(sizeof(struct tc_taprio_sched_entry) * num_entries +
-                       sizeof(struct tc_taprio_qopt_offload), GFP_KERNEL);
+       dummy = kzalloc(struct_size(dummy, entries, num_entries), GFP_KERNEL);
        if (!dummy) {
                NL_SET_ERR_MSG_MOD(extack, "Failed to allocate memory");
                return true;