Merge branch 'net-constify-dev_addr-passing-for-protocols'

Jakub Kicinski says:

====================
net: constify dev_addr passing for protocols

Commit 406f42f ("net-next: When a bond have a massive amount
of VLANs...") introduced a rbtree for faster Ethernet address look
up. To maintain netdev->dev_addr in this tree we need to make all
the writes to it got through appropriate helpers.

netdev->dev_addr will be made const to prevent direct writes.
This set sprinkles const across variables and arguments in protocol
code which are used to hold references to netdev->dev_addr.
====================

Link: https://lore.kernel.org/r/20211012155840.4151590-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

include/net/ax25.h

@@ -304,7 +304,7 @@ extern spinlock_t ax25_list_lock;
 void ax25_cb_add(ax25_cb *);
 struct sock *ax25_find_listener(ax25_address *, int, struct net_device *, int);
 struct sock *ax25_get_socket(ax25_address *, ax25_address *, int);
-ax25_cb *ax25_find_cb(ax25_address *, ax25_address *, ax25_digi *,
+ax25_cb *ax25_find_cb(const ax25_address *, ax25_address *, ax25_digi *,
 		      struct net_device *);
 void ax25_send_to_raw(ax25_address *, struct sk_buff *, int);
 void ax25_destroy_socket(ax25_cb *);
@@ -384,10 +384,11 @@ struct ax25_linkfail {
 
 void ax25_linkfail_register(struct ax25_linkfail *lf);
 void ax25_linkfail_release(struct ax25_linkfail *lf);
-int __must_check ax25_listen_register(ax25_address *, struct net_device *);
-void ax25_listen_release(ax25_address *, struct net_device *);
+int __must_check ax25_listen_register(const ax25_address *,
+				      struct net_device *);
+void ax25_listen_release(const ax25_address *, struct net_device *);
 int(*ax25_protocol_function(unsigned int))(struct sk_buff *, ax25_cb *);
-int ax25_listen_mine(ax25_address *, struct net_device *);
+int ax25_listen_mine(const ax25_address *, struct net_device *);
 void ax25_link_failed(ax25_cb *, int);
 int ax25_protocol_is_registered(unsigned int);
 
@@ -401,8 +402,8 @@ netdev_tx_t ax25_ip_xmit(struct sk_buff *skb);
 extern const struct header_ops ax25_header_ops;
 
 /* ax25_out.c */
-ax25_cb *ax25_send_frame(struct sk_buff *, int, ax25_address *, ax25_address *,
-			 ax25_digi *, struct net_device *);
+ax25_cb *ax25_send_frame(struct sk_buff *, int, const ax25_address *,
+			 ax25_address *, ax25_digi *, struct net_device *);
 void ax25_output(ax25_cb *, int, struct sk_buff *);
 void ax25_kick(ax25_cb *);
 void ax25_transmit_buffer(ax25_cb *, struct sk_buff *, int);

include/net/datalink.h

@@ -12,7 +12,7 @@ struct datalink_proto {
         int     (*rcvfunc)(struct sk_buff *, struct net_device *,
                                 struct packet_type *, struct net_device *);
 	int     (*request)(struct datalink_proto *, struct sk_buff *,
-                                        unsigned char *);
+			   const unsigned char *);
 	struct list_head node;
 };
 

include/net/dn.h

@@ -166,7 +166,7 @@ struct dn_skb_cb {
 	int iif;
 };
 
-static inline __le16 dn_eth2dn(unsigned char *ethaddr)
+static inline __le16 dn_eth2dn(const unsigned char *ethaddr)
 {
 	return get_unaligned((__le16 *)(ethaddr + 4));
 }

include/net/llc.h

@@ -133,7 +133,7 @@ static inline void llc_sap_put(struct llc_sap *sap)
 struct llc_sap *llc_sap_find(unsigned char sap_value);
 
 int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
-			      unsigned char *dmac, unsigned char dsap);
+			      const unsigned char *dmac, unsigned char dsap);
 
 void llc_sap_handler(struct llc_sap *sap, struct sk_buff *skb);
 void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb);

include/net/llc_if.h

@@ -62,7 +62,8 @@
 #define LLC_STATUS_CONFLICT	7 /* disconnect conn */
 #define LLC_STATUS_RESET_DONE	8 /*  */
 
-int llc_establish_connection(struct sock *sk, u8 *lmac, u8 *dmac, u8 dsap);
+int llc_establish_connection(struct sock *sk, const u8 *lmac, u8 *dmac,
+			     u8 dsap);
 int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb);
 int llc_send_disc(struct sock *sk);
 #endif /* LLC_IF_H */

include/net/ndisc.h

@@ -137,7 +137,7 @@ struct ndisc_options *ndisc_parse_options(const struct net_device *dev,
 					  u8 *opt, int opt_len,
 					  struct ndisc_options *ndopts);
 
-void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
+void __ndisc_fill_addr_option(struct sk_buff *skb, int type, const void *data,
 			      int data_len, int pad);
 
 #define NDISC_OPS_REDIRECT_DATA_SPACE	2

include/net/rose.h

@@ -162,8 +162,8 @@ extern int  sysctl_rose_link_fail_timeout;
 extern int  sysctl_rose_maximum_vcs;
 extern int  sysctl_rose_window_size;
 
-int rosecmp(rose_address *, rose_address *);
-int rosecmpm(rose_address *, rose_address *, unsigned short);
+int rosecmp(const rose_address *, const rose_address *);
+int rosecmpm(const rose_address *, const rose_address *, unsigned short);
 char *rose2asc(char *buf, const rose_address *);
 struct sock *rose_find_socket(unsigned int, struct rose_neigh *);
 void rose_kill_by_neigh(struct rose_neigh *);
@@ -205,8 +205,8 @@ extern const struct seq_operations rose_node_seqops;
 extern struct seq_operations rose_route_seqops;
 
 void rose_add_loopback_neigh(void);
-int __must_check rose_add_loopback_node(rose_address *);
-void rose_del_loopback_node(rose_address *);
+int __must_check rose_add_loopback_node(const rose_address *);
+void rose_del_loopback_node(const rose_address *);
 void rose_rt_device_down(struct net_device *);
 void rose_link_device_down(struct net_device *);
 struct net_device *rose_dev_first(void);

net/802/p8022.c

@@ -23,7 +23,7 @@
 #include <net/p8022.h>
 
 static int p8022_request(struct datalink_proto *dl, struct sk_buff *skb,
-			 unsigned char *dest)
+			 const unsigned char *dest)
 {
 	llc_build_and_send_ui_pkt(dl->sap, skb, dest, dl->sap->laddr.lsap);
 	return 0;

net/802/psnap.c

@@ -79,7 +79,7 @@ static int snap_rcv(struct sk_buff *skb, struct net_device *dev,
  *	Put a SNAP header on a frame and pass to 802.2
  */
 static int snap_request(struct datalink_proto *dl,
-			struct sk_buff *skb, u8 *dest)
+			struct sk_buff *skb, const u8 *dest)
 {
 	memcpy(skb_push(skb, 5), dl->type, 5);
 	llc_build_and_send_ui_pkt(snap_sap, skb, dest, snap_sap->laddr.lsap);

net/ax25/af_ax25.c

@@ -202,7 +202,7 @@ struct sock *ax25_get_socket(ax25_address *my_addr, ax25_address *dest_addr,
  *	Find an AX.25 control block given both ends. It will only pick up
  *	floating AX.25 control blocks or non Raw socket bound control blocks.
  */
-ax25_cb *ax25_find_cb(ax25_address *src_addr, ax25_address *dest_addr,
+ax25_cb *ax25_find_cb(const ax25_address *src_addr, ax25_address *dest_addr,
 	ax25_digi *digi, struct net_device *dev)
 {
 	ax25_cb *s;

net/ax25/ax25_dev.c

@@ -35,7 +35,7 @@ ax25_dev *ax25_addr_ax25dev(ax25_address *addr)
 
 	spin_lock_bh(&ax25_dev_lock);
 	for (ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next)
-		if (ax25cmp(addr, (ax25_address *)ax25_dev->dev->dev_addr) == 0) {
+		if (ax25cmp(addr, (const ax25_address *)ax25_dev->dev->dev_addr) == 0) {
 			res = ax25_dev;
 		}
 	spin_unlock_bh(&ax25_dev_lock);

net/ax25/ax25_iface.c

@@ -98,7 +98,7 @@ void ax25_linkfail_release(struct ax25_linkfail *lf)
 
 EXPORT_SYMBOL(ax25_linkfail_release);
 
-int ax25_listen_register(ax25_address *callsign, struct net_device *dev)
+int ax25_listen_register(const ax25_address *callsign, struct net_device *dev)
 {
 	struct listen_struct *listen;
 
@@ -121,7 +121,7 @@ int ax25_listen_register(ax25_address *callsign, struct net_device *dev)
 
 EXPORT_SYMBOL(ax25_listen_register);
 
-void ax25_listen_release(ax25_address *callsign, struct net_device *dev)
+void ax25_listen_release(const ax25_address *callsign, struct net_device *dev)
 {
 	struct listen_struct *s, *listen;
 
@@ -171,7 +171,7 @@ int (*ax25_protocol_function(unsigned int pid))(struct sk_buff *, ax25_cb *)
 	return res;
 }
 
-int ax25_listen_mine(ax25_address *callsign, struct net_device *dev)
+int ax25_listen_mine(const ax25_address *callsign, struct net_device *dev)
 {
 	struct listen_struct *listen;
 

net/ax25/ax25_in.c

@@ -181,7 +181,7 @@ static int ax25_process_rx_frame(ax25_cb *ax25, struct sk_buff *skb, int type, i
 }
 
 static int ax25_rcv(struct sk_buff *skb, struct net_device *dev,
-	ax25_address *dev_addr, struct packet_type *ptype)
+		    const ax25_address *dev_addr, struct packet_type *ptype)
 {
 	ax25_address src, dest, *next_digi = NULL;
 	int type = 0, mine = 0, dama;
@@ -447,5 +447,5 @@ int ax25_kiss_rcv(struct sk_buff *skb, struct net_device *dev,
 
 	skb_pull(skb, AX25_KISS_HEADER_LEN);	/* Remove the KISS byte */
 
-	return ax25_rcv(skb, dev, (ax25_address *)dev->dev_addr, ptype);
+	return ax25_rcv(skb, dev, (const ax25_address *)dev->dev_addr, ptype);
 }

net/ax25/ax25_out.c

@@ -29,7 +29,7 @@
 
 static DEFINE_SPINLOCK(ax25_frag_lock);
 
-ax25_cb *ax25_send_frame(struct sk_buff *skb, int paclen, ax25_address *src, ax25_address *dest, ax25_digi *digi, struct net_device *dev)
+ax25_cb *ax25_send_frame(struct sk_buff *skb, int paclen, const ax25_address *src, ax25_address *dest, ax25_digi *digi, struct net_device *dev)
 {
 	ax25_dev *ax25_dev;
 	ax25_cb *ax25;

net/ipv6/addrconf.c

@@ -2237,12 +2237,12 @@ static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
 
 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
 {
-	union fwnet_hwaddr *ha;
+	const union fwnet_hwaddr *ha;
 
 	if (dev->addr_len != FWNET_ALEN)
 		return -1;
 
-	ha = (union fwnet_hwaddr *)dev->dev_addr;
+	ha = (const union fwnet_hwaddr *)dev->dev_addr;
 
 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
 	eui[0] ^= 2;

net/ipv6/ndisc.c

@@ -142,7 +142,7 @@ struct neigh_table nd_tbl = {
 };
 EXPORT_SYMBOL_GPL(nd_tbl);
 
-void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
+void __ndisc_fill_addr_option(struct sk_buff *skb, int type, const void *data,
 			      int data_len, int pad)
 {
 	int space = __ndisc_opt_addr_space(data_len, pad);
@@ -165,7 +165,7 @@ void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,
 EXPORT_SYMBOL_GPL(__ndisc_fill_addr_option);
 
 static inline void ndisc_fill_addr_option(struct sk_buff *skb, int type,
-					  void *data, u8 icmp6_type)
+					  const void *data, u8 icmp6_type)
 {
 	__ndisc_fill_addr_option(skb, type, data, skb->dev->addr_len,
 				 ndisc_addr_option_pad(skb->dev->type));

net/llc/llc_c_ac.c

@@ -781,7 +781,7 @@ int llc_conn_ac_send_sabme_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
 
 	if (nskb) {
 		struct llc_sap *sap = llc->sap;
-		u8 *dmac = llc->daddr.mac;
+		const u8 *dmac = llc->daddr.mac;
 
 		if (llc->dev->flags & IFF_LOOPBACK)
 			dmac = llc->dev->dev_addr;

net/llc/llc_if.c

@@ -80,7 +80,7 @@ int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb)
  *	establishment will inform to upper layer via calling it's confirm
  *	function and passing proper information.
  */
-int llc_establish_connection(struct sock *sk, u8 *lmac, u8 *dmac, u8 dsap)
+int llc_establish_connection(struct sock *sk, const u8 *lmac, u8 *dmac, u8 dsap)
 {
 	int rc = -EISCONN;
 	struct llc_addr laddr, daddr;

net/llc/llc_output.c

@@ -56,7 +56,7 @@ int llc_mac_hdr_init(struct sk_buff *skb,
  *	package primitive as an event and send to SAP event handler
  */
 int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
-			      unsigned char *dmac, unsigned char dsap)
+			      const unsigned char *dmac, unsigned char dsap)
 {
 	int rc;
 	llc_pdu_header_init(skb, LLC_PDU_TYPE_U, sap->laddr.lsap,

net/llc/llc_proc.c

@@ -26,7 +26,7 @@
 #include <net/llc_c_st.h>
 #include <net/llc_conn.h>
 
-static void llc_ui_format_mac(struct seq_file *seq, u8 *addr)
+static void llc_ui_format_mac(struct seq_file *seq, const u8 *addr)
 {
 	seq_printf(seq, "%pM", addr);
 }

net/netrom/af_netrom.c

@@ -633,7 +633,7 @@ static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
 	struct sock *sk = sock->sk;
 	struct nr_sock *nr = nr_sk(sk);
 	struct sockaddr_ax25 *addr = (struct sockaddr_ax25 *)uaddr;
-	ax25_address *source = NULL;
+	const ax25_address *source = NULL;
 	ax25_uid_assoc *user;
 	struct net_device *dev;
 	int err = 0;
@@ -673,7 +673,7 @@ static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
 			err = -ENETUNREACH;
 			goto out_release;
 		}
-		source = (ax25_address *)dev->dev_addr;
+		source = (const ax25_address *)dev->dev_addr;
 
 		user = ax25_findbyuid(current_euid());
 		if (user) {

net/netrom/nr_dev.c

@@ -108,7 +108,7 @@ static int __must_check nr_set_mac_address(struct net_device *dev, void *addr)
 		if (err)
 			return err;
 
-		ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
+		ax25_listen_release((const ax25_address *)dev->dev_addr, NULL);
 	}
 
 	dev_addr_set(dev, sa->sa_data);
@@ -120,7 +120,7 @@ static int nr_open(struct net_device *dev)
 {
 	int err;
 
-	err = ax25_listen_register((ax25_address *)dev->dev_addr, NULL);
+	err = ax25_listen_register((const ax25_address *)dev->dev_addr, NULL);
 	if (err)
 		return err;
 
@@ -131,7 +131,7 @@ static int nr_open(struct net_device *dev)
 
 static int nr_close(struct net_device *dev)
 {
-	ax25_listen_release((ax25_address *)dev->dev_addr, NULL);
+	ax25_listen_release((const ax25_address *)dev->dev_addr, NULL);
 	netif_stop_queue(dev);
 	return 0;
 }

net/netrom/nr_route.c

@@ -598,7 +598,7 @@ struct net_device *nr_dev_get(ax25_address *addr)
 	rcu_read_lock();
 	for_each_netdev_rcu(&init_net, dev) {
 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
-		    ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
+		    ax25cmp(addr, (const ax25_address *)dev->dev_addr) == 0) {
 			dev_hold(dev);
 			goto out;
 		}
@@ -825,7 +825,7 @@ int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
 
 	ax25s = nr_neigh->ax25;
 	nr_neigh->ax25 = ax25_send_frame(skb, 256,
-					 (ax25_address *)dev->dev_addr,
+					 (const ax25_address *)dev->dev_addr,
 					 &nr_neigh->callsign,
 					 nr_neigh->digipeat, nr_neigh->dev);
 	if (ax25s)

net/rose/af_rose.c

@@ -109,7 +109,7 @@ char *rose2asc(char *buf, const rose_address *addr)
 /*
  *	Compare two ROSE addresses, 0 == equal.
  */
-int rosecmp(rose_address *addr1, rose_address *addr2)
+int rosecmp(const rose_address *addr1, const rose_address *addr2)
 {
 	int i;
 
@@ -123,7 +123,8 @@ int rosecmp(rose_address *addr1, rose_address *addr2)
 /*
  *	Compare two ROSE addresses for only mask digits, 0 == equal.
  */
-int rosecmpm(rose_address *addr1, rose_address *addr2, unsigned short mask)
+int rosecmpm(const rose_address *addr1, const rose_address *addr2,
+	     unsigned short mask)
 {
 	unsigned int i, j;
 

net/rose/rose_dev.c

@@ -66,7 +66,7 @@ static int rose_set_mac_address(struct net_device *dev, void *addr)
 		if (err)
 			return err;
 
-		rose_del_loopback_node((rose_address *)dev->dev_addr);
+		rose_del_loopback_node((const rose_address *)dev->dev_addr);
 	}
 
 	dev_addr_set(dev, sa->sa_data);
@@ -78,7 +78,7 @@ static int rose_open(struct net_device *dev)
 {
 	int err;
 
-	err = rose_add_loopback_node((rose_address *)dev->dev_addr);
+	err = rose_add_loopback_node((const rose_address *)dev->dev_addr);
 	if (err)
 		return err;
 
@@ -90,7 +90,7 @@ static int rose_open(struct net_device *dev)
 static int rose_close(struct net_device *dev)
 {
 	netif_stop_queue(dev);
-	rose_del_loopback_node((rose_address *)dev->dev_addr);
+	rose_del_loopback_node((const rose_address *)dev->dev_addr);
 	return 0;
 }
 

net/rose/rose_link.c

@@ -94,11 +94,11 @@ static void rose_t0timer_expiry(struct timer_list *t)
  */
 static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh)
 {
-	ax25_address *rose_call;
+	const ax25_address *rose_call;
 	ax25_cb *ax25s;
 
 	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
-		rose_call = (ax25_address *)neigh->dev->dev_addr;
+		rose_call = (const ax25_address *)neigh->dev->dev_addr;
 	else
 		rose_call = &rose_callsign;
 
@@ -117,11 +117,11 @@ static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh)
  */
 static int rose_link_up(struct rose_neigh *neigh)
 {
-	ax25_address *rose_call;
+	const ax25_address *rose_call;
 	ax25_cb *ax25s;
 
 	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
-		rose_call = (ax25_address *)neigh->dev->dev_addr;
+		rose_call = (const ax25_address *)neigh->dev->dev_addr;
 	else
 		rose_call = &rose_callsign;