fsl/fman: check dereferencing null pointer

Add a safe check to avoid dereferencing null pointer

Fixes: 57ba4c9b ("fsl/fman: Add FMan MAC support")
Signed-off-by: Florinel Iordache <florinel.iordache@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/fman/fman_dtsec.c

@@ -1200,7 +1200,7 @@ int dtsec_del_hash_mac_address(struct fman_mac *dtsec, enet_addr_t *eth_addr)
 		list_for_each(pos,
 			      &dtsec->multicast_addr_hash->lsts[bucket]) {
 			hash_entry = ETH_HASH_ENTRY_OBJ(pos);
-			if (hash_entry->addr == addr) {
+			if (hash_entry && hash_entry->addr == addr) {
 				list_del_init(&hash_entry->node);
 				kfree(hash_entry);
 				break;
@@ -1213,7 +1213,7 @@ int dtsec_del_hash_mac_address(struct fman_mac *dtsec, enet_addr_t *eth_addr)
 		list_for_each(pos,
 			      &dtsec->unicast_addr_hash->lsts[bucket]) {
 			hash_entry = ETH_HASH_ENTRY_OBJ(pos);
-			if (hash_entry->addr == addr) {
+			if (hash_entry && hash_entry->addr == addr) {
 				list_del_init(&hash_entry->node);
 				kfree(hash_entry);
 				break;

drivers/net/ethernet/freescale/fman/fman_memac.c

@@ -981,7 +981,7 @@ int memac_del_hash_mac_address(struct fman_mac *memac, enet_addr_t *eth_addr)
 
 	list_for_each(pos, &memac->multicast_addr_hash->lsts[hash]) {
 		hash_entry = ETH_HASH_ENTRY_OBJ(pos);
-		if (hash_entry->addr == addr) {
+		if (hash_entry && hash_entry->addr == addr) {
 			list_del_init(&hash_entry->node);
 			kfree(hash_entry);
 			break;

drivers/net/ethernet/freescale/fman/fman_tgec.c

@@ -626,7 +626,7 @@ int tgec_del_hash_mac_address(struct fman_mac *tgec, enet_addr_t *eth_addr)
 
 	list_for_each(pos, &tgec->multicast_addr_hash->lsts[hash]) {
 		hash_entry = ETH_HASH_ENTRY_OBJ(pos);
-		if (hash_entry->addr == addr) {
+		if (hash_entry && hash_entry->addr == addr) {
 			list_del_init(&hash_entry->node);
 			kfree(hash_entry);
 			break;