1 files changed, 68 insertions, 96 deletions

diff --git a/net/appletalk/aarp.c b/net/appletalk/aarp.c
index 690356fa52b9..4744e3fd4544 100644
--- a/net/appletalk/aarp.c
+++ b/net/appletalk/aarp.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *	AARP:		An implementation of the AppleTalk AARP protocol for
  *			Ethernet 'ELAP'.
@@ -13,12 +14,6 @@
  *		Use neighbour discovery code.
  *		Token Ring Support.
  *
- *		This program is free software; you can redistribute it and/or
- *		modify it under the terms of the GNU General Public License
- *		as published by the Free Software Foundation; either version
- *		2 of the License, or (at your option) any later version.
- *
- *
  *	References:
  *		Inside AppleTalk (2nd Ed).
  *	Fixes:
@@ -26,7 +21,6 @@
  *		Rob Newberry	-	Added proxy AARP and AARP proc fs,
  *					moved probing from DDP module.
  *		Arnaldo C. Melo -	don't mangle rx packets
- *
  */
 
 #include <linux/if_arp.h>
@@ -40,6 +34,8 @@
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/export.h>
+#include <linux/etherdevice.h>
+#include <linux/refcount.h>
 
 int sysctl_aarp_expiry_time = AARP_EXPIRY_TIME;
 int sysctl_aarp_tick_time = AARP_TICK_TIME;
@@ -49,17 +45,19 @@ int sysctl_aarp_resolve_time = AARP_RESOLVE_TIME;
 /* Lists of aarp entries */
 /**
  *	struct aarp_entry - AARP entry
- *	@last_sent - Last time we xmitted the aarp request
- *	@packet_queue - Queue of frames wait for resolution
- *	@status - Used for proxy AARP
- *	expires_at - Entry expiry time
- *	target_addr - DDP Address
- *	dev - Device to use
- *	hwaddr - Physical i/f address of target/router
- *	xmit_count - When this hits 10 we give up
- *	next - Next entry in chain
+ *	@refcnt: Reference count
+ *	@last_sent: Last time we xmitted the aarp request
+ *	@packet_queue: Queue of frames wait for resolution
+ *	@status: Used for proxy AARP
+ *	@expires_at: Entry expiry time
+ *	@target_addr: DDP Address
+ *	@dev:  Device to use
+ *	@hwaddr:  Physical i/f address of target/router
+ *	@xmit_count:  When this hits 10 we give up
+ *	@next: Next entry in chain
  */
 struct aarp_entry {
+	refcount_t			refcnt;
 	/* These first two are only used for unresolved entries */
 	unsigned long		last_sent;
 	struct sk_buff_head	packet_queue;
@@ -67,7 +65,7 @@ struct aarp_entry {
 	unsigned long		expires_at;
 	struct atalk_addr	target_addr;
 	struct net_device	*dev;
-	char			hwaddr[6];
+	char			hwaddr[ETH_ALEN];
 	unsigned short		xmit_count;
 	struct aarp_entry	*next;
 };
@@ -84,6 +82,17 @@ static DEFINE_RWLOCK(aarp_lock);
 /* Used to walk the list and purge/kick entries.  */
 static struct timer_list aarp_timer;
 
+static inline void aarp_entry_get(struct aarp_entry *a)
+{
+	refcount_inc(&a->refcnt);
+}
+
+static inline void aarp_entry_put(struct aarp_entry *a)
+{
+	if (refcount_dec_and_test(&a->refcnt))
+		kfree(a);
+}
+
 /*
  *	Delete an aarp queue
  *
@@ -92,7 +101,7 @@ static struct timer_list aarp_timer;
 static void __aarp_expire(struct aarp_entry *a)
 {
 	skb_queue_purge(&a->packet_queue);
-	kfree(a);
+	aarp_entry_put(a);
 }
 
 /*
@@ -134,13 +143,13 @@ static void __aarp_send_query(struct aarp_entry *a)
 	eah->pa_len	 = AARP_PA_ALEN;
 	eah->function	 = htons(AARP_REQUEST);
 
-	memcpy(eah->hw_src, dev->dev_addr, ETH_ALEN);
+	ether_addr_copy(eah->hw_src, dev->dev_addr);
 
 	eah->pa_src_zero = 0;
 	eah->pa_src_net	 = sat->s_net;
 	eah->pa_src_node = sat->s_node;
 
-	memset(eah->hw_dst, '\0', ETH_ALEN);
+	eth_zero_addr(eah->hw_dst);
 
 	eah->pa_dst_zero = 0;
 	eah->pa_dst_net	 = a->target_addr.s_net;
@@ -181,16 +190,16 @@ static void aarp_send_reply(struct net_device *dev, struct atalk_addr *us,
 	eah->pa_len	 = AARP_PA_ALEN;
 	eah->function	 = htons(AARP_REPLY);
 
-	memcpy(eah->hw_src, dev->dev_addr, ETH_ALEN);
+	ether_addr_copy(eah->hw_src, dev->dev_addr);
 
 	eah->pa_src_zero = 0;
 	eah->pa_src_net	 = us->s_net;
 	eah->pa_src_node = us->s_node;
 
 	if (!sha)
-		memset(eah->hw_dst, '\0', ETH_ALEN);
+		eth_zero_addr(eah->hw_dst);
 	else
-		memcpy(eah->hw_dst, sha, ETH_ALEN);
+		ether_addr_copy(eah->hw_dst, sha);
 
 	eah->pa_dst_zero = 0;
 	eah->pa_dst_net	 = them->s_net;
@@ -232,13 +241,13 @@ static void aarp_send_probe(struct net_device *dev, struct atalk_addr *us)
 	eah->pa_len	 = AARP_PA_ALEN;
 	eah->function	 = htons(AARP_PROBE);
 
-	memcpy(eah->hw_src, dev->dev_addr, ETH_ALEN);
+	ether_addr_copy(eah->hw_src, dev->dev_addr);
 
 	eah->pa_src_zero = 0;
 	eah->pa_src_net	 = us->s_net;
 	eah->pa_src_node = us->s_node;
 
-	memset(eah->hw_dst, '\0', ETH_ALEN);
+	eth_zero_addr(eah->hw_dst);
 
 	eah->pa_dst_zero = 0;
 	eah->pa_dst_net	 = us->s_net;
@@ -309,7 +318,7 @@ static void __aarp_expire_device(struct aarp_entry **n, struct net_device *dev)
 }
 
 /* Handle the timer event */
-static void aarp_expire_timeout(unsigned long unused)
+static void aarp_expire_timeout(struct timer_list *unused)
 {
 	int ct;
 
@@ -385,9 +394,11 @@ static void aarp_purge(void)
 static struct aarp_entry *aarp_alloc(void)
 {
 	struct aarp_entry *a = kmalloc(sizeof(*a), GFP_ATOMIC);
+	if (!a)
+		return NULL;
 
-	if (a)
-		skb_queue_head_init(&a->packet_queue);
+	refcount_set(&a->refcnt, 1);
+	skb_queue_head_init(&a->packet_queue);
 	return a;
 }
 
@@ -437,49 +448,18 @@ static struct atalk_addr *__aarp_proxy_find(struct net_device *dev,
 	return a ? sa : NULL;
 }
 
-/*
- * Probe a Phase 1 device or a device that requires its Net:Node to
- * be set via an ioctl.
- */
-static void aarp_send_probe_phase1(struct atalk_iface *iface)
-{
-	struct ifreq atreq;
-	struct sockaddr_at *sa = (struct sockaddr_at *)&atreq.ifr_addr;
-	const struct net_device_ops *ops = iface->dev->netdev_ops;
-
-	sa->sat_addr.s_node = iface->address.s_node;
-	sa->sat_addr.s_net = ntohs(iface->address.s_net);
-
-	/* We pass the Net:Node to the drivers/cards by a Device ioctl. */
-	if (!(ops->ndo_do_ioctl(iface->dev, &atreq, SIOCSIFADDR))) {
-		ops->ndo_do_ioctl(iface->dev, &atreq, SIOCGIFADDR);
-		if (iface->address.s_net != htons(sa->sat_addr.s_net) ||
-		    iface->address.s_node != sa->sat_addr.s_node)
-			iface->status |= ATIF_PROBE_FAIL;
-
-		iface->address.s_net  = htons(sa->sat_addr.s_net);
-		iface->address.s_node = sa->sat_addr.s_node;
-	}
-}
-
-
 void aarp_probe_network(struct atalk_iface *atif)
 {
-	if (atif->dev->type == ARPHRD_LOCALTLK ||
-	    atif->dev->type == ARPHRD_PPP)
-		aarp_send_probe_phase1(atif);
-	else {
-		unsigned int count;
+	unsigned int count;
 
-		for (count = 0; count < AARP_RETRANSMIT_LIMIT; count++) {
-			aarp_send_probe(atif->dev, &atif->address);
+	for (count = 0; count < AARP_RETRANSMIT_LIMIT; count++) {
+		aarp_send_probe(atif->dev, &atif->address);
 
-			/* Defer 1/10th */
-			msleep(100);
+		/* Defer 1/10th */
+		msleep(100);
 
-			if (atif->status & ATIF_PROBE_FAIL)
-				break;
-		}
+		if (atif->status & ATIF_PROBE_FAIL)
+			break;
 	}
 }
 
@@ -513,6 +493,7 @@ int aarp_proxy_probe_network(struct atalk_iface *atif, struct atalk_addr *sa)
 	entry->dev = atif->dev;
 
 	write_lock_bh(&aarp_lock);
+	aarp_entry_get(entry);
 
 	hash = sa->s_node % (AARP_HASH_SIZE - 1);
 	entry->next = proxies[hash];
@@ -538,6 +519,7 @@ int aarp_proxy_probe_network(struct atalk_iface *atif, struct atalk_addr *sa)
 		retval = 1;
 	}
 
+	aarp_entry_put(entry);
 	write_unlock_bh(&aarp_lock);
 out:
 	return retval;
@@ -669,7 +651,7 @@ out_unlock:
 
 sendit:
 	if (skb->sk)
-		skb->priority = skb->sk->sk_priority;
+		skb->priority = READ_ONCE(skb->sk->sk_priority);
 	if (dev_queue_xmit(skb))
 		goto drop;
 sent:
@@ -773,7 +755,7 @@ static int aarp_rcv(struct sk_buff *skb, struct net_device *dev,
 	if (a && a->status & ATIF_PROBE) {
 		a->status |= ATIF_PROBE_FAIL;
 		/*
-		 * we do not respond to probe or request packets for
+		 * we do not respond to probe or request packets of
 		 * this address while we are probing this address
 		 */
 		goto unlock;
@@ -790,7 +772,7 @@ static int aarp_rcv(struct sk_buff *skb, struct net_device *dev,
 			break;
 
 		/* We can fill one in - this is good. */
-		memcpy(a->hwaddr, ea->hw_src, ETH_ALEN);
+		ether_addr_copy(a->hwaddr, ea->hw_src);
 		__aarp_resolved(&unresolved[hash], a, hash);
 		if (!unresolved_count)
 			mod_timer(&aarp_timer,
@@ -878,15 +860,24 @@ static struct notifier_block aarp_notifier = {
 
 static unsigned char aarp_snap_id[] = { 0x00, 0x00, 0x00, 0x80, 0xF3 };
 
-void __init aarp_proto_init(void)
+int __init aarp_proto_init(void)
 {
+	int rc;
+
 	aarp_dl = register_snap_client(aarp_snap_id, aarp_rcv);
-	if (!aarp_dl)
+	if (!aarp_dl) {
 		printk(KERN_CRIT "Unable to register AARP with SNAP.\n");
-	setup_timer(&aarp_timer, aarp_expire_timeout, 0);
+		return -ENOMEM;
+	}
+	timer_setup(&aarp_timer, aarp_expire_timeout, 0);
 	aarp_timer.expires  = jiffies + sysctl_aarp_expiry_time;
 	add_timer(&aarp_timer);
-	register_netdevice_notifier(&aarp_notifier);
+	rc = register_netdevice_notifier(&aarp_notifier);
+	if (rc) {
+		timer_delete_sync(&aarp_timer);
+		unregister_snap_client(aarp_dl);
+	}
+	return rc;
 }
 
 /* Remove the AARP entries associated with a device. */
@@ -906,11 +897,6 @@ void aarp_device_down(struct net_device *dev)
 }
 
 #ifdef CONFIG_PROC_FS
-struct aarp_iter_state {
-	int bucket;
-	struct aarp_entry **table;
-};
-
 /*
  * Get the aarp entry that is in the chain described
  * by the iterator.
@@ -925,7 +911,7 @@ static struct aarp_entry *iter_next(struct aarp_iter_state *iter, loff_t *pos)
 	struct aarp_entry *entry;
 
  rescan:
-	while(ct < AARP_HASH_SIZE) {
+	while (ct < AARP_HASH_SIZE) {
 		for (entry = table[ct]; entry; entry = entry->next) {
 			if (!pos || ++off == *pos) {
 				iter->table = table;
@@ -994,7 +980,7 @@ static const char *dt2str(unsigned long ticks)
 {
 	static char buf[32];
 
-	sprintf(buf, "%ld.%02ld", ticks / HZ, ((ticks % HZ) * 100 ) / HZ);
+	sprintf(buf, "%ld.%02ld", ticks / HZ, ((ticks % HZ) * 100) / HZ);
 
 	return buf;
 }
@@ -1032,32 +1018,18 @@ static int aarp_seq_show(struct seq_file *seq, void *v)
 	return 0;
 }
 
-static const struct seq_operations aarp_seq_ops = {
+const struct seq_operations aarp_seq_ops = {
 	.start  = aarp_seq_start,
 	.next   = aarp_seq_next,
 	.stop   = aarp_seq_stop,
 	.show   = aarp_seq_show,
 };
-
-static int aarp_seq_open(struct inode *inode, struct file *file)
-{
-	return seq_open_private(file, &aarp_seq_ops,
-			sizeof(struct aarp_iter_state));
-}
-
-const struct file_operations atalk_seq_arp_fops = {
-	.owner		= THIS_MODULE,
-	.open           = aarp_seq_open,
-	.read           = seq_read,
-	.llseek         = seq_lseek,
-	.release	= seq_release_private,
-};
 #endif
 
 /* General module cleanup. Called from cleanup_module() in ddp.c. */
 void aarp_cleanup_module(void)
 {
-	del_timer_sync(&aarp_timer);
+	timer_delete_sync(&aarp_timer);
 	unregister_netdevice_notifier(&aarp_notifier);
 	unregister_snap_client(aarp_dl);
 	aarp_purge();