Merge dea.linux-mips.net:/usr/src/bk/linux-2.5

into dea.linux-mips.net:/home/ralf/src/ax25/linux-2.5

include/net/ax25.h

@@ -3,11 +3,12 @@
  *
  *	Alan Cox (GW4PTS) 	10/11/93
  */
- 
 #ifndef _AX25_H
 #define _AX25_H 
+
 #include <linux/config.h>
 #include <linux/ax25.h>
+#include <linux/spinlock.h>
 
 #define	AX25_T1CLAMPLO  		1
 #define	AX25_T1CLAMPHI 			(30 * HZ)
@@ -197,7 +198,8 @@ typedef struct ax25_cb {
 #define ax25_sk(__sk) ((ax25_cb *)(__sk)->protinfo)
 
 /* af_ax25.c */
-extern ax25_cb *volatile ax25_list;
+extern ax25_cb *ax25_list;
+extern spinlock_t ax25_list_lock;
 extern void ax25_free_cb(ax25_cb *);
 extern void ax25_insert_socket(ax25_cb *);
 struct sock *ax25_find_listener(ax25_address *, int, struct net_device *, int);
@@ -224,6 +226,7 @@ extern void ax25_digi_invert(ax25_digi *, ax25_digi *);
 
 /* ax25_dev.c */
 extern ax25_dev *ax25_dev_list;
+extern spinlock_t ax25_dev_lock;
 extern ax25_dev *ax25_dev_ax25dev(struct net_device *);
 extern ax25_dev *ax25_addr_ax25dev(ax25_address *);
 extern void ax25_dev_device_up(struct net_device *);

net/ax25/TODO

+af_ax25.c:ax25_connect:
+
+	There is a race with changing the socket state here which should be
+	fixed by introduction of proper socket locking:
+
+        if (sk->state != TCP_ESTABLISHED) {
+                /* Not in ABM, not in WAIT_UA -> failed */
+                sock->state = SS_UNCONNECTED;
+                return sock_error(sk);  /* Always set at this point */
+        }
+
+Do the ax25_list_lock, ax25_uid_lock, ax25_route_lock, protocol_list_lock,
+ax25_dev_lock, linkfail_lockreally, ax25_frag_lock and listen_lock have to
+be interrupt safe?

net/ax25/af_ax25.c

@@ -114,6 +114,7 @@
 #include <linux/sched.h>
 #include <linux/timer.h>
 #include <linux/string.h>
+#include <linux/smp_lock.h>
 #include <linux/sockios.h>
 #include <linux/net.h>
 #include <net/ax25.h>
@@ -134,13 +135,15 @@
 #include <linux/netfilter.h>
 #include <linux/sysctl.h>
 #include <linux/init.h>
+#include <linux/spinlock.h>
 #include <net/tcp.h>
 #include <net/ip.h>
 #include <net/arp.h>
 
 
 
-ax25_cb *volatile ax25_list;
+ax25_cb *ax25_list;
+spinlock_t ax25_list_lock = SPIN_LOCK_UNLOCKED;
 
 static struct proto_ops ax25_proto_ops;
 
@@ -173,25 +176,25 @@ static void ax25_remove_socket(ax25_cb *ax25)
 	ax25_cb *s;
 	unsigned long flags;
 
-	save_flags(flags); cli();
+	spin_lock_irqsave(&ax25_list_lock, flags);
 
 	if ((s = ax25_list) == ax25) {
 		ax25_list = s->next;
-		restore_flags(flags);
+		spin_unlock_irqrestore(&ax25_list_lock, flags);
 		return;
 	}
 
 	while (s != NULL && s->next != NULL) {
 		if (s->next == ax25) {
 			s->next = ax25->next;
-			restore_flags(flags);
+			spin_unlock_irqrestore(&ax25_list_lock, flags);
 			return;
 		}
 
 		s = s->next;
 	}
 
-	restore_flags(flags);
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 }
 
 /*
@@ -199,18 +202,21 @@ static void ax25_remove_socket(ax25_cb *ax25)
  */
 static void ax25_kill_by_device(struct net_device *dev)
 {
+	unsigned long flags;
 	ax25_dev *ax25_dev;
 	ax25_cb *s;
 
 	if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
 		return;
 
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	for (s = ax25_list; s != NULL; s = s->next) {
 		if (s->ax25_dev == ax25_dev) {
 			s->ax25_dev = NULL;
 			ax25_disconnect(s, ENETUNREACH);
 		}
 	}
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 }
 
 /*
@@ -247,13 +253,10 @@ void ax25_insert_socket(ax25_cb *ax25)
 {
 	unsigned long flags;
 
-	save_flags(flags);
-	cli();
-
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	ax25->next = ax25_list;
 	ax25_list  = ax25;
-
-	restore_flags(flags);
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 }
 
 /*
@@ -265,22 +268,21 @@ struct sock *ax25_find_listener(ax25_address *addr, int digi, struct net_device
 	unsigned long flags;
 	ax25_cb *s;
 
-	save_flags(flags);
-	cli();
-
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	for (s = ax25_list; s != NULL; s = s->next) {
 		if ((s->iamdigi && !digi) || (!s->iamdigi && digi))
 			continue;
 		if (s->sk != NULL && ax25cmp(&s->source_addr, addr) == 0 && s->sk->type == type && s->sk->state == TCP_LISTEN) {
 			/* If device is null we match any device */
 			if (s->ax25_dev == NULL || s->ax25_dev->dev == dev) {
-				restore_flags(flags);
+				spin_unlock_irqrestore(&ax25_list_lock, flags);
+
 				return s->sk;
 			}
 		}
 	}
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 
-	restore_flags(flags);
 	return NULL;
 }
 
@@ -292,17 +294,15 @@ struct sock *ax25_find_socket(ax25_address *my_addr, ax25_address *dest_addr, in
 	ax25_cb *s;
 	unsigned long flags;
 
-	save_flags(flags);
-	cli();
-
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	for (s = ax25_list; s != NULL; s = s->next) {
 		if (s->sk != NULL && ax25cmp(&s->source_addr, my_addr) == 0 && ax25cmp(&s->dest_addr, dest_addr) == 0 && s->sk->type == type) {
-			restore_flags(flags);
+			spin_unlock_irqrestore(&ax25_list_lock, flags);
+
 			return s->sk;
 		}
 	}
-
-	restore_flags(flags);
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 
 	return NULL;
 }
@@ -316,9 +316,7 @@ ax25_cb *ax25_find_cb(ax25_address *src_addr, ax25_address *dest_addr, ax25_digi
 	ax25_cb *s;
 	unsigned long flags;
 
-	save_flags(flags);
-	cli();
-
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	for (s = ax25_list; s != NULL; s = s->next) {
 		if (s->sk != NULL && s->sk->type != SOCK_SEQPACKET)
 			continue;
@@ -334,12 +332,12 @@ ax25_cb *ax25_find_cb(ax25_address *src_addr, ax25_address *dest_addr, ax25_digi
 				if (s->digipeat != NULL && s->digipeat->ndigi != 0)
 					continue;
 			}
-			restore_flags(flags);
+			spin_unlock_irqrestore(&ax25_list_lock, flags);
+
 			return s;
 		}
 	}
-
-	restore_flags(flags);
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 
 	return NULL;
 }
@@ -352,17 +350,14 @@ struct sock *ax25_addr_match(ax25_address *addr)
 	unsigned long flags;
 	ax25_cb *s;
 
-	save_flags(flags);
-	cli();
-
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	for (s = ax25_list; s != NULL; s = s->next) {
 		if (s->sk != NULL && ax25cmp(&s->source_addr, addr) == 0 && s->sk->type == SOCK_RAW) {
-			restore_flags(flags);
+			spin_unlock_irqrestore(&ax25_list_lock, flags);
 			return s->sk;
 		}
 	}
-
-	restore_flags(flags);
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 
 	return NULL;
 }
@@ -634,10 +629,10 @@ ax25_cb *ax25_create_cb(void)
 static int ax25_setsockopt(struct socket *sock, int level, int optname, char *optval, int optlen)
 {
 	struct sock *sk = sock->sk;
-	ax25_cb *ax25 = ax25_sk(sk);
+	ax25_cb *ax25;
 	struct net_device *dev;
 	char devname[IFNAMSIZ];
-	int opt;
+	int opt, res = 0;
 
 	if (level != SOL_AX25)
 		return -ENOPROTOOPT;
@@ -648,98 +643,130 @@ static int ax25_setsockopt(struct socket *sock, int level, int optname, char *op
 	if (get_user(opt, (int *)optval))
 		return -EFAULT;
 
+	lock_kernel();
+	ax25 = ax25_sk(sk);
+
 	switch (optname) {
 	case AX25_WINDOW:
 		if (ax25->modulus == AX25_MODULUS) {
-				if (opt < 1 || opt > 7)
-					return -EINVAL;
+			if (opt < 1 || opt > 7) {
+				res = -EINVAL;
+				break;
+			}
 		} else {
-				if (opt < 1 || opt > 63)
-					return -EINVAL;
+			if (opt < 1 || opt > 63) {
+				res = -EINVAL;
+				break;
+			}
 		}
 		ax25->window = opt;
-			return 0;
+		break;
 
 	case AX25_T1:
-			if (opt < 1)
-				return -EINVAL;
+		if (opt < 1) {
+			res = -EINVAL;
+			break;
+		}
 		ax25->rtt = (opt * HZ) / 2;
 		ax25->t1  = opt * HZ;
-			return 0;
+		break;
 
 	case AX25_T2:
-			if (opt < 1)
-				return -EINVAL;
+		if (opt < 1) {
+			res = -EINVAL;
+			break;
+		}
 		ax25->t2 = opt * HZ;
-			return 0;
+		break;
 
 	case AX25_N2:
-			if (opt < 1 || opt > 31)
-				return -EINVAL;
+		if (opt < 1 || opt > 31) {
+			res = -EINVAL;
+			break;
+		}
 		ax25->n2 = opt;
-			return 0;
+		break;
 
 	case AX25_T3:
-			if (opt < 1)
-				return -EINVAL;
+		if (opt < 1) {
+			res = -EINVAL;
+			break;
+		}
 		ax25->t3 = opt * HZ;
-			return 0;
+		break;
 
 	case AX25_IDLE:
-			if (opt < 0)
-				return -EINVAL;
+		if (opt < 0) {
+			res = -EINVAL;
+			break;
+		}
 		ax25->idle = opt * 60 * HZ;
-			return 0;
+		break;
 
 	case AX25_BACKOFF:
-			if (opt < 0 || opt > 2)
-				return -EINVAL;
+		if (opt < 0 || opt > 2) {
+			res = -EINVAL;
+			break;
+		}
 		ax25->backoff = opt;
-			return 0;
+		break;
 
 	case AX25_EXTSEQ:
 		ax25->modulus = opt ? AX25_EMODULUS : AX25_MODULUS;
-			return 0;
+		break;
 
 	case AX25_PIDINCL:
 		ax25->pidincl = opt ? 1 : 0;
-			return 0;
+		break;
 
 	case AX25_IAMDIGI:
 		ax25->iamdigi = opt ? 1 : 0;
-			return 0;
+		break;
 
 	case AX25_PACLEN:
-			if (opt < 16 || opt > 65535)
-				return -EINVAL;
+		if (opt < 16 || opt > 65535) {
+			res = -EINVAL;
+			break;
+		}
 		ax25->paclen = opt;
-			return 0;
+		break;
 
 	case SO_BINDTODEVICE:
-			if (optlen > IFNAMSIZ) optlen=IFNAMSIZ;
-			if (copy_from_user(devname, optval, optlen))
-				return -EFAULT;
+		if (optlen > IFNAMSIZ)
+			optlen=IFNAMSIZ;
+		if (copy_from_user(devname, optval, optlen)) {
+		res = -EFAULT;
+			break;
+		}
 
 		dev = dev_get_by_name(devname);
-			if (dev == NULL) return -ENODEV;
+		if (dev == NULL) {
+			res = -ENODEV;
+			break;
+		}
 
 		if (sk->type == SOCK_SEQPACKET && 
-			   (sock->state != SS_UNCONNECTED || sk->state == TCP_LISTEN))
-				return -EADDRNOTAVAIL;
+		   (sock->state != SS_UNCONNECTED || sk->state == TCP_LISTEN)) {
+			res = -EADDRNOTAVAIL;
+			break;
+		}
 		
 		ax25->ax25_dev = ax25_dev_ax25dev(dev);
 		ax25_fillin_cb(ax25, ax25->ax25_dev);
-			return 0;
+		break;
 
 	default:
-			return -ENOPROTOOPT;
+		res = -ENOPROTOOPT;
 	}
+	unlock_kernel();
+
+	return res;
 }
 
 static int ax25_getsockopt(struct socket *sock, int level, int optname, char *optval, int *optlen)
 {
 	struct sock *sk = sock->sk;
-	ax25_cb *ax25 = ax25_sk(sk);
+	ax25_cb *ax25;
 	struct ax25_dev *ax25_dev;
 	char devname[IFNAMSIZ];
 	void *valptr;
@@ -758,6 +785,9 @@ static int ax25_getsockopt(struct socket *sock, int level, int optname, char *op
 	valptr = (void *) &val;
 	length = min_t(unsigned int, maxlen, sizeof(int));
 
+	lock_kernel();
+	ax25 = ax25_sk(sk);
+
 	switch (optname) {
 	case AX25_WINDOW:
 		val = ax25->window;
@@ -819,8 +849,10 @@ static int ax25_getsockopt(struct socket *sock, int level, int optname, char *op
 		break;
 
 	default:
+		unlock_kernel();
 		return -ENOPROTOOPT;
 	}
+	unlock_kernel();
 
 	if (put_user(length, optlen))
 		return -EFAULT;
@@ -832,11 +864,14 @@ static int ax25_listen(struct socket *sock, int backlog)
 {
 	struct sock *sk = sock->sk;
 
+	lock_kernel();
 	if (sk->type == SOCK_SEQPACKET && sk->state != TCP_LISTEN) {
 		sk->max_ack_backlog = backlog;
 		sk->state           = TCP_LISTEN;
+		unlock_kernel();
 		return 0;
 	}
+	unlock_kernel();
 
 	return -EOPNOTSUPP;
 }
@@ -851,6 +886,7 @@ int ax25_create(struct socket *sock, int protocol)
 		if (protocol == 0 || protocol == PF_AX25)
 			protocol = AX25_P_TEXT;
 		break;
+
 	case SOCK_SEQPACKET:
 		switch (protocol) {
 		case 0:
@@ -883,6 +919,7 @@ int ax25_create(struct socket *sock, int protocol)
 			break;
 		}
 		break;
+
 	case SOCK_RAW:
 		break;
 	default:
@@ -985,7 +1022,11 @@ static int ax25_release(struct socket *sock)
 	struct sock *sk = sock->sk;
 	ax25_cb *ax25;
 
-	if (sk == NULL) return 0;
+	lock_kernel();
+	if (sk == NULL) {
+		unlock_kernel();
+		return 0;
+	}
 
 	ax25 = ax25_sk(sk);
 
@@ -1048,6 +1089,7 @@ static int ax25_release(struct socket *sock)
 
 	sock->sk   = NULL;	
 	sk->socket = NULL;	/* Not used, but we should do this */
+	unlock_kernel();
 
 	return 0;
 }
@@ -1066,26 +1108,35 @@ static int ax25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 	ax25_address *call;
 	ax25_dev *ax25_dev = NULL;
 
-	if (sk->zapped == 0)
+	lock_kernel();
+	if (sk->zapped == 0) {
+		unlock_kernel();
 		return -EINVAL;
+	}
 
 	if (addr_len != sizeof(struct sockaddr_ax25) && 
 	    addr_len != sizeof(struct full_sockaddr_ax25)) {
 		/* support for old structure may go away some time */
 		if ((addr_len < sizeof(struct sockaddr_ax25) + sizeof(ax25_address) * 6) ||
-		    (addr_len > sizeof(struct full_sockaddr_ax25)))
+		    (addr_len > sizeof(struct full_sockaddr_ax25))) {
+			unlock_kernel();
 			return -EINVAL;
+	}
 
 		printk(KERN_WARNING "ax25_bind(): %s uses old (6 digipeater) socket structure.\n",
 			current->comm);
 	}
 
-	if (addr->fsa_ax25.sax25_family != AF_AX25)
+	if (addr->fsa_ax25.sax25_family != AF_AX25) {
+		unlock_kernel();
 		return -EINVAL;
+	}
 
 	call = ax25_findbyuid(current->euid);
-	if (call == NULL && ax25_uid_policy && !capable(CAP_NET_ADMIN))
+	if (call == NULL && ax25_uid_policy && !capable(CAP_NET_ADMIN)) {
+		unlock_kernel();
 		return -EACCES;
+	}
 
 	if (call == NULL)
 		ax25->source_addr = addr->fsa_ax25.sax25_call;
@@ -1101,12 +1152,16 @@ static int ax25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 
 	if (addr_len > sizeof(struct sockaddr_ax25) && addr->fsa_ax25.sax25_ndigis == 1) {
 		if (ax25cmp(&addr->fsa_digipeater[0], &null_ax25_address) != 0 &&
-		    (ax25_dev = ax25_addr_ax25dev(&addr->fsa_digipeater[0])) == NULL)
+		    (ax25_dev = ax25_addr_ax25dev(&addr->fsa_digipeater[0])) == NULL) {
+			unlock_kernel();
 			return -EADDRNOTAVAIL;
+		}
 	}  else {
-		if ((ax25_dev = ax25_addr_ax25dev(&addr->fsa_ax25.sax25_call)) == NULL)
+		if ((ax25_dev = ax25_addr_ax25dev(&addr->fsa_ax25.sax25_call)) == NULL) {
+			unlock_kernel();
 			return -EADDRNOTAVAIL;
 		}
+	}
 
 	if (ax25_dev != NULL)
 		ax25_fillin_cb(ax25, ax25_dev);
@@ -1114,6 +1169,8 @@ static int ax25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 done:
 	ax25_insert_socket(ax25);
 	sk->zapped = 0;
+	unlock_kernel();
+
 	return 0;
 }
 
@@ -1128,24 +1185,30 @@ static int ax25_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le
 	ax25_digi *digi = NULL;
 	int ct = 0, err;
 
+	lock_kernel();
 	/* deal with restarts */
 	if (sock->state == SS_CONNECTING) {
 		switch (sk->state) {
 		case TCP_SYN_SENT: /* still trying */
+			unlock_kernel();
 			return -EINPROGRESS;
 
 		case TCP_ESTABLISHED: /* connection established */
+			unlock_kernel();
 			sock->state = SS_CONNECTED;
 			return 0;
 
 		case TCP_CLOSE: /* connection refused */
+			unlock_kernel();
 			sock->state = SS_UNCONNECTED;
 			return -ECONNREFUSED;
 		}
 	}
 
-	if (sk->state == TCP_ESTABLISHED && sk->type == SOCK_SEQPACKET)
+	if (sk->state == TCP_ESTABLISHED && sk->type == SOCK_SEQPACKET) {
+		unlock_kernel();
 		return -EISCONN;	/* No reconnect on a seqpacket socket */
+	}
 
 	sk->state   = TCP_CLOSE;
 	sock->state = SS_UNCONNECTED;
@@ -1162,15 +1225,19 @@ static int ax25_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le
 	else if (addr_len != sizeof(struct full_sockaddr_ax25)) {
 		/* support for old structure may go away some time */
 		if ((addr_len < sizeof(struct sockaddr_ax25) + sizeof(ax25_address) * 6) ||
-		    (addr_len > sizeof(struct full_sockaddr_ax25)))
+		    (addr_len > sizeof(struct full_sockaddr_ax25))) {
+			unlock_kernel();
 			return -EINVAL;
+		}
 
 		printk(KERN_WARNING "ax25_connect(): %s uses old (6 digipeater) socket structure.\n",
 			current->comm);
 	}
 
-	if (fsa->fsa_ax25.sax25_family != AF_AX25)
+	if (fsa->fsa_ax25.sax25_family != AF_AX25) {
+		unlock_kernel();
 		return -EINVAL;
+	}
 
 	if (ax25->digipeat != NULL) {
 		kfree(ax25->digipeat);
@@ -1182,11 +1249,15 @@ static int ax25_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le
 	 */
 	if (addr_len > sizeof(struct sockaddr_ax25) && fsa->fsa_ax25.sax25_ndigis != 0) {
 		/* Valid number of digipeaters ? */
-		if (fsa->fsa_ax25.sax25_ndigis < 1 || fsa->fsa_ax25.sax25_ndigis > AX25_MAX_DIGIS)
+		if (fsa->fsa_ax25.sax25_ndigis < 1 || fsa->fsa_ax25.sax25_ndigis > AX25_MAX_DIGIS) {
+			unlock_kernel();
 			return -EINVAL;
+		}
 
-		if ((digi = kmalloc(sizeof(ax25_digi), GFP_KERNEL)) == NULL)
+		if ((digi = kmalloc(sizeof(ax25_digi), GFP_KERNEL)) == NULL) {
+			unlock_kernel();
 			return -ENOBUFS;
+		}
 
 		digi->ndigi      = fsa->fsa_ax25.sax25_ndigis;
 		digi->lastrepeat = -1;
@@ -1218,14 +1289,18 @@ static int ax25_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le
 		ax25_fillin_cb(ax25, ax25->ax25_dev);
 		ax25_insert_socket(ax25);
 	} else {
-		if (ax25->ax25_dev == NULL)
+		if (ax25->ax25_dev == NULL) {
+			unlock_kernel();
 			return -EHOSTUNREACH;
 		}
+	}
 
 	if (sk->type == SOCK_SEQPACKET &&
 	    ax25_find_cb(&ax25->source_addr, &fsa->fsa_ax25.sax25_call, digi,
 		    	 ax25->ax25_dev->dev)) {
-		if (digi != NULL) kfree(digi);
+		if (digi != NULL)
+			kfree(digi);
+		unlock_kernel();
 		return -EADDRINUSE;			/* Already such a connection */
 	}
 
@@ -1236,6 +1311,7 @@ static int ax25_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le
 	if (sk->type != SOCK_SEQPACKET) {
 		sock->state = SS_CONNECTED;
 		sk->state   = TCP_ESTABLISHED;
+		unlock_kernel();
 		return 0;
 	}
 
@@ -1252,8 +1328,7 @@ static int ax25_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le
 #ifdef CONFIG_AX25_DAMA_SLAVE
 	case AX25_PROTO_DAMA_SLAVE:
 		ax25->modulus = AX25_MODULUS;
-			ax25->window  =
-				ax25->ax25_dev->values[AX25_VALUES_WINDOW];
+		ax25->window  = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
 		if (ax25->ax25_dev->dama.slave)
 			ax25_ds_establish_data_link(ax25);
 		else
@@ -1267,30 +1342,38 @@ static int ax25_connect(struct socket *sock, struct sockaddr *uaddr, int addr_le
 	ax25_start_heartbeat(ax25);
 
 	/* Now the loop */
-	if (sk->state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
+	if (sk->state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
+		unlock_kernel();
 		return -EINPROGRESS;
+	}
 
-	cli();	/* To avoid races on the sleep */
+	if (sk->state == TCP_SYN_SENT) {
+		struct task_struct *tsk = current;
+		DECLARE_WAITQUEUE(wait, tsk);
 
-	/* A DM or timeout will go to closed, a UA will go to ABM */
-	while (sk->state == TCP_SYN_SENT) {
-		interruptible_sleep_on(sk->sleep);
-		if (signal_pending(current)) {
-			sti();
+		add_wait_queue(sk->sleep, &wait);
+		for (;;) {
+			set_current_state(TASK_INTERRUPTIBLE);
+			if (sk->state != TCP_SYN_SENT)
+				break;
+			if (!signal_pending(tsk)) {
+				schedule();
+				continue;
+			}
 			return -ERESTARTSYS;
 		}
+		current->state = TASK_RUNNING;
+		remove_wait_queue(sk->sleep, &wait);
 	}
 
 	if (sk->state != TCP_ESTABLISHED) {
 		/* Not in ABM, not in WAIT_UA -> failed */
-		sti();
 		sock->state = SS_UNCONNECTED;
 		return sock_error(sk);	/* Always set at this point */
 	}
 
 	sock->state = SS_CONNECTED;
-
-	sti();
+	unlock_kernel();
 
 	return 0;
 }
@@ -1302,17 +1385,26 @@ static int ax25_accept(struct socket *sock, struct socket *newsock, int flags)
 	struct sock *newsk;
 	struct sk_buff *skb;
 
-	if (sock->state != SS_UNCONNECTED)
+	lock_kernel();
+	if (sock->state != SS_UNCONNECTED) {
+		unlock_kernel();
 		return -EINVAL;
+	}
 
-	if ((sk = sock->sk) == NULL)
+	if ((sk = sock->sk) == NULL) {
+		unlock_kernel();
 		return -EINVAL;
+	}
 
-	if (sk->type != SOCK_SEQPACKET)
+	if (sk->type != SOCK_SEQPACKET) {
+		unlock_kernel();
 		return -EOPNOTSUPP;
+	}
 
-	if (sk->state != TCP_LISTEN)
+	if (sk->state != TCP_LISTEN) {
+		unlock_kernel();
 		return -EINVAL;
+	}
 
 	/*
 	 *	The read queue this time is holding sockets ready to use
@@ -1320,13 +1412,17 @@ static int ax25_accept(struct socket *sock, struct socket *newsock, int flags)
 	 */
 	do {
 		if ((skb = skb_dequeue(&sk->receive_queue)) == NULL) {
-			if (flags & O_NONBLOCK)
+			if (flags & O_NONBLOCK) {
+				unlock_kernel();
 				return -EWOULDBLOCK;
+			}
 
 			interruptible_sleep_on(sk->sleep);
-			if (signal_pending(current)) 
+			if (signal_pending(current)) {
+				unlock_kernel();
 				return -ERESTARTSYS;
 			}
+		}
 	} while (skb == NULL);
 
 	newsk = skb->sk;
@@ -1339,20 +1435,27 @@ static int ax25_accept(struct socket *sock, struct socket *newsock, int flags)
 	sk->ack_backlog--;
 	newsock->sk    = newsk;
 	newsock->state = SS_CONNECTED;
+	unlock_kernel();
 
 	return 0;
 }
 
 static int ax25_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, int peer)
 {
-	struct sock *sk = sock->sk;
-	ax25_cb *ax25 = ax25_sk(sk);
+	struct sock *sk;
+	ax25_cb *ax25;
 	struct full_sockaddr_ax25 *fsa = (struct full_sockaddr_ax25 *)uaddr;
 	unsigned char ndigi, i;
 
+	lock_kernel();
+	sk = sock->sk;
+	ax25 = ax25_sk(sk);
+
 	if (peer != 0) {
-		if (sk->state != TCP_ESTABLISHED)
+		if (sk->state != TCP_ESTABLISHED) {
+			unlock_kernel();
 			return -ENOTCONN;
+		}
 
 		fsa->fsa_ax25.sax25_family = AF_AX25;
 		fsa->fsa_ax25.sax25_call   = ax25->dest_addr;
@@ -1377,13 +1480,15 @@ static int ax25_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_
 		}
 	}
 	*uaddr_len = sizeof (struct full_sockaddr_ax25);
+	unlock_kernel();
+
 	return 0;
 }
 
 static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct scm_cookie *scm)
 {
 	struct sock *sk = sock->sk;
-	ax25_cb *ax25 = ax25_sk(sk);
+	ax25_cb *ax25;
 	struct sockaddr_ax25 *usax = (struct sockaddr_ax25 *)msg->msg_name;
 	int err;
 	struct sockaddr_ax25 sax;
@@ -1395,23 +1500,34 @@ static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct
 	int lv;
 	int addr_len = msg->msg_namelen;
 
-	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR))
+	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR)) {
 		return -EINVAL;
+	}
+
+	lock_kernel();
+	ax25 = ax25_sk(sk);
 
-	if (sk->zapped)
+	if (sk->zapped) {
+		unlock_kernel();
 		return -EADDRNOTAVAIL;
+	}
 
 	if (sk->shutdown & SEND_SHUTDOWN) {
+		unlock_kernel();
 		send_sig(SIGPIPE, current, 0);
 		return -EPIPE;
 	}
 
-	if (ax25->ax25_dev == NULL)
+	if (ax25->ax25_dev == NULL) {
+		unlock_kernel();
 		return -ENETUNREACH;
+	}
 
 	if (usax != NULL) {
-		if (usax->sax25_family != AF_AX25)
+		if (usax->sax25_family != AF_AX25) {
+			unlock_kernel();
 			return -EINVAL;
+		}
 
 		if (addr_len == sizeof(struct sockaddr_ax25)) {
 			printk(KERN_WARNING "ax25_sendmsg(): %s uses obsolete socket structure\n",
@@ -1420,8 +1536,10 @@ static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct
 		else if (addr_len != sizeof(struct full_sockaddr_ax25)) {
 			/* support for old structure may go away some time */
 			if ((addr_len < sizeof(struct sockaddr_ax25) + sizeof(ax25_address) * 6) ||
-		    	    (addr_len > sizeof(struct full_sockaddr_ax25)))
+		    	    (addr_len > sizeof(struct full_sockaddr_ax25))) {
+				unlock_kernel();
 		    		return -EINVAL;
+			}
 
 			printk(KERN_WARNING "ax25_sendmsg(): %s uses old (6 digipeater) socket structure.\n",
 				current->comm);
@@ -1432,8 +1550,10 @@ static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct
 			struct full_sockaddr_ax25 *fsa = (struct full_sockaddr_ax25 *)usax;
 
 			/* Valid number of digipeaters ? */
-			if (usax->sax25_ndigis < 1 || usax->sax25_ndigis > AX25_MAX_DIGIS)
+			if (usax->sax25_ndigis < 1 || usax->sax25_ndigis > AX25_MAX_DIGIS) {
+				unlock_kernel();
 				return -EINVAL;
+			}
 
 			dtmp.ndigi      = usax->sax25_ndigis;
 
@@ -1447,8 +1567,10 @@ static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct
 		}
 
 		sax = *usax;
-		if (sk->type == SOCK_SEQPACKET && ax25cmp(&ax25->dest_addr, &sax.sax25_call) != 0)
+		if (sk->type == SOCK_SEQPACKET && ax25cmp(&ax25->dest_addr, &sax.sax25_call) != 0) {
+			unlock_kernel();
 			return -EISCONN;
+		}
 		if (usax->sax25_ndigis == 0)
 			dp = NULL;
 		else
@@ -1474,8 +1596,10 @@ static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct
 	/* Assume the worst case */
 	size = len + 3 + ax25_addr_size(dp) + AX25_BPQ_HEADER_LEN;
 
-	if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
+	if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL) {
+		unlock_kernel();
 		return err;
+	}
 
 	skb_reserve(skb, size - len);
 
@@ -1497,11 +1621,13 @@ static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct
 		/* Connected mode sockets go via the LAPB machine */
 		if (sk->state != TCP_ESTABLISHED) {
 			kfree_skb(skb);
+			unlock_kernel();
 			return -ENOTCONN;
 		}
 
 		/* Shove it onto the queue and kick */
 		ax25_output(ax25, ax25->paclen, skb);
+		unlock_kernel();
 
 		return len;
 	} else {
@@ -1529,6 +1655,7 @@ static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct
 		skb->dev = ax25->ax25_dev->dev;
 
 		ax25_queue_xmit(skb);
+		unlock_kernel();
 
 		return len;
 	}
@@ -1536,21 +1663,28 @@ static int ax25_sendmsg(struct socket *sock, struct msghdr *msg, int len, struct
 
 static int ax25_recvmsg(struct socket *sock, struct msghdr *msg, int size, int flags, struct scm_cookie *scm)
 {
-	struct sock *sk = sock->sk;
+	struct sock *sk;
 	int copied;
 	struct sk_buff *skb;
 	int er;
 
+	lock_kernel();
+	sk = sock->sk;
+
 	/*
 	 * 	This works for seqpacket too. The receiver has ordered the
 	 *	queue for us! We do one quick check first though
 	 */
-	if (sk->type == SOCK_SEQPACKET && sk->state != TCP_ESTABLISHED)
+	if (sk->type == SOCK_SEQPACKET && sk->state != TCP_ESTABLISHED) {
+		unlock_kernel();
 		return -ENOTCONN;
+	}
 
 	/* Now we can treat all alike */
-	if ((skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &er)) == NULL)
+	if ((skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &er)) == NULL) {
+		unlock_kernel();
 		return er;
+	}
 
 	if (!ax25_sk(sk)->pidincl)
 		skb_pull(skb, 1);		/* Remove PID */
@@ -1590,6 +1724,7 @@ static int ax25_recvmsg(struct socket *sock, struct msghdr *msg, int size, int f
 	}
 
 	skb_free_datagram(sk, skb);
+	unlock_kernel();
 
 	return copied;
 }
@@ -1603,14 +1738,17 @@ static int ax25_shutdown(struct socket *sk, int how)
 static int ax25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 {
 	struct sock *sk = sock->sk;
+	int res = 0;
 
+	lock_kernel();
 	switch (cmd) {
 	case TIOCOUTQ: {
 		long amount;
 		amount = sk->sndbuf - atomic_read(&sk->wmem_alloc);
 		if (amount < 0)
 			amount = 0;
-			return put_user(amount, (int *)arg);
+		res = put_user(amount, (int *)arg);
+		break;
 	}
 
 	case TIOCINQ: {
@@ -1619,49 +1757,70 @@ static int ax25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 		/* These two are safe on a single CPU system as only user tasks fiddle here */
 		if ((skb = skb_peek(&sk->receive_queue)) != NULL)
 			amount = skb->len;
-			return put_user(amount, (int *)arg);
+		res = put_user(amount, (int *)arg);
+		break;
 	}
 
 	case SIOCGSTAMP:
 		if (sk != NULL) {
-				if (sk->stamp.tv_sec == 0)
-					return -ENOENT;
-				return copy_to_user((void *)arg, &sk->stamp, sizeof(struct timeval)) ? -EFAULT : 0;
+			if (sk->stamp.tv_sec == 0) {
+				res = -ENOENT;
+				break;
 			}
-			return -EINVAL;
+			res = copy_to_user((void *)arg, &sk->stamp, sizeof(struct timeval)) ? -EFAULT : 0;
+			break;
+	 	}
+		res = -EINVAL;
+		break;
 
 	case SIOCAX25ADDUID:	/* Add a uid to the uid/call map table */
 	case SIOCAX25DELUID:	/* Delete a uid from the uid/call map table */
 	case SIOCAX25GETUID: {
 		struct sockaddr_ax25 sax25;
-			if (copy_from_user(&sax25, (void *)arg, sizeof(sax25)))
-				return -EFAULT;
-			return ax25_uid_ioctl(cmd, &sax25);
+		if (copy_from_user(&sax25, (void *)arg, sizeof(sax25))) {
+			res = -EFAULT;
+			break;
+		}
+		res = ax25_uid_ioctl(cmd, &sax25);
+		break;
 	}
 
 	case SIOCAX25NOUID: {	/* Set the default policy (default/bar) */
 		long amount;
-			if (!capable(CAP_NET_ADMIN))
-				return -EPERM;
-			if (get_user(amount, (long *)arg))
-				return -EFAULT;
-			if (amount > AX25_NOUID_BLOCK)
-				return -EINVAL;
+		if (!capable(CAP_NET_ADMIN)) {
+			res = -EPERM;
+			break;
+		}
+		if (get_user(amount, (long *)arg)) {
+			res = -EFAULT;
+			break;
+		}
+		if (amount > AX25_NOUID_BLOCK) {
+			res = -EINVAL;
+			break;
+		}
 		ax25_uid_policy = amount;
-			return 0;
+		res = 0;
+		break;
 	}
 
 	case SIOCADDRT:
 	case SIOCDELRT:
 	case SIOCAX25OPTRT:
-			if (!capable(CAP_NET_ADMIN))
-				return -EPERM;
-			return ax25_rt_ioctl(cmd, (void *)arg);
+		if (!capable(CAP_NET_ADMIN)) {
+			res = -EPERM;
+			break;
+		}
+		res = ax25_rt_ioctl(cmd, (void *)arg);
+		break;
 
 	case SIOCAX25CTLCON:
-			if (!capable(CAP_NET_ADMIN))
-				return -EPERM;
-			return ax25_ctl_ioctl(cmd, (void *)arg);
+		if (!capable(CAP_NET_ADMIN)) {
+			res = -EPERM;
+			break;
+		}
+		res = ax25_ctl_ioctl(cmd, (void *)arg);
+		break;
 
 	case SIOCAX25GETINFO: 
 	case SIOCAX25GETINFOOLD: {
@@ -1697,23 +1856,33 @@ static int ax25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 				warned=1;
 			}
 
-				if (copy_to_user((void *)arg, &ax25_info, sizeof(struct ax25_info_struct_depreciated)))
-					return -EFAULT;
+			if (copy_to_user((void *)arg, &ax25_info, sizeof(struct ax25_info_struct_depreciated))) {
+				res = -EFAULT;
+				break;
+			}
 		} else {
-				if (copy_to_user((void *)arg, &ax25_info, sizeof(struct ax25_info_struct)))
-					return -EINVAL;
+			if (copy_to_user((void *)arg, &ax25_info, sizeof(struct ax25_info_struct))) {
+				res = -EINVAL;
+				break;
 			}
-			return 0;
+		} 
+		res = 0;
+		break;
 	}
 
 	case SIOCAX25ADDFWD:
 	case SIOCAX25DELFWD: {
 		struct ax25_fwd_struct ax25_fwd;
-			if (!capable(CAP_NET_ADMIN))
-				return -EPERM;
-			if (copy_from_user(&ax25_fwd, (void *)arg, sizeof(ax25_fwd)))
-				return -EFAULT;
-			return ax25_fwd_ioctl(cmd, &ax25_fwd);
+		if (!capable(CAP_NET_ADMIN)) {
+			res = -EPERM;
+			break;
+		}
+		if (copy_from_user(&ax25_fwd, (void *)arg, sizeof(ax25_fwd))) {
+			res = -EFAULT;
+			break;
+		}
+		res = ax25_fwd_ioctl(cmd, &ax25_fwd);
+		break;
 	}
 
 	case SIOCGIFADDR:
@@ -1726,25 +1895,28 @@ static int ax25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 	case SIOCSIFNETMASK:
 	case SIOCGIFMETRIC:
 	case SIOCSIFMETRIC:
-			return -EINVAL;
+		res = -EINVAL;
+		break;
 
 	default:
-			return dev_ioctl(cmd, (void *)arg);
+		res = dev_ioctl(cmd, (void *)arg);
+		break;
 	}
 
-	/*NOTREACHED*/
-	return 0;
+	unlock_kernel();
+	return res;
 }
 
 static int ax25_get_info(char *buffer, char **start, off_t offset, int length)
 {
+	unsigned long flags;
 	ax25_cb *ax25;
 	int k;
 	int len = 0;
 	off_t pos = 0;
 	off_t begin = 0;
 
-	cli();
+	spin_lock_irqsave(&ax25_list_lock, flags);
 
 	/*
 	 * New format:
@@ -1799,7 +1971,7 @@ static int ax25_get_info(char *buffer, char **start, off_t offset, int length)
 			break;
 	}
 
-	sti();
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 
 	*start = buffer + (offset - begin);
 	len   -= (offset - begin);
@@ -1814,7 +1986,7 @@ static struct net_proto_family ax25_family_ops = {
 	create:		ax25_create,
 };
 
-static struct proto_ops SOCKOPS_WRAPPED(ax25_proto_ops) = {
+static struct proto_ops ax25_proto_ops = {
 	family:		PF_AX25,
 
 	release:	ax25_release,

net/ax25/ax25_dev.c

@@ -27,6 +27,7 @@
 #include <linux/string.h>
 #include <linux/sockios.h>
 #include <linux/net.h>
+#include <linux/spinlock.h>
 #include <net/ax25.h>
 #include <linux/inet.h>
 #include <linux/netdevice.h>
@@ -41,27 +42,37 @@
 #include <linux/init.h>
 
 ax25_dev *ax25_dev_list;
+spinlock_t ax25_dev_lock = SPIN_LOCK_UNLOCKED;
 
 ax25_dev *ax25_dev_ax25dev(struct net_device *dev)
 {
-	ax25_dev *ax25_dev;
+	ax25_dev *ax25_dev, *res = NULL;
+	unsigned long flags;
 
+	spin_lock_irqsave(&ax25_dev_lock, flags);
 	for (ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next)
-		if (ax25_dev->dev == dev)
-			return ax25_dev;
+		if (ax25_dev->dev == dev) {
+			res = ax25_dev;
+			break;
+		}
+	spin_unlock_irqrestore(&ax25_dev_lock, flags);
 
-	return NULL;
+	return res;
 }
 
 ax25_dev *ax25_addr_ax25dev(ax25_address *addr)
 {
-	ax25_dev *ax25_dev;
+	ax25_dev *ax25_dev, *res = NULL;
+	unsigned long flags;
 
+	spin_lock_irqsave(&ax25_dev_lock, flags);
 	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)
-			return ax25_dev;
+		if (ax25cmp(addr, (ax25_address *)ax25_dev->dev->dev_addr) == 0) {
+			res = ax25_dev;
+		}
+	spin_unlock_irqrestore(&ax25_dev_lock, flags);
 
-	return NULL;
+	return res;
 }
 
 /*
@@ -100,10 +111,10 @@ void ax25_dev_device_up(struct net_device *dev)
 	ax25_dev->values[AX25_VALUES_PROTOCOL]  = AX25_DEF_PROTOCOL;
 	ax25_dev->values[AX25_VALUES_DS_TIMEOUT]= AX25_DEF_DS_TIMEOUT;
 
-	save_flags(flags); cli();
+	spin_lock_irqsave(&ax25_dev_lock, flags);
 	ax25_dev->next = ax25_dev_list;
 	ax25_dev_list  = ax25_dev;
-	restore_flags(flags);
+	spin_unlock_irqrestore(&ax25_dev_lock, flags);
 
 	ax25_register_sysctl();
 }
@@ -118,7 +129,7 @@ void ax25_dev_device_down(struct net_device *dev)
 
 	ax25_unregister_sysctl();
 
-	save_flags(flags); cli();
+	spin_lock_irqsave(&ax25_dev_lock, flags);
 
 #ifdef CONFIG_AX25_DAMA_SLAVE
 	ax25_ds_del_timer(ax25_dev);
@@ -133,7 +144,7 @@ void ax25_dev_device_down(struct net_device *dev)
 
 	if ((s = ax25_dev_list) == ax25_dev) {
 		ax25_dev_list = s->next;
-		restore_flags(flags);
+		spin_unlock_irqrestore(&ax25_dev_lock, flags);
 		kfree(ax25_dev);
 		ax25_register_sysctl();
 		return;
@@ -142,7 +153,7 @@ void ax25_dev_device_down(struct net_device *dev)
 	while (s != NULL && s->next != NULL) {
 		if (s->next == ax25_dev) {
 			s->next = ax25_dev->next;
-			restore_flags(flags);
+			spin_unlock_irqrestore(&ax25_dev_lock, flags);
 			kfree(ax25_dev);
 			ax25_register_sysctl();
 			return;
@@ -150,8 +161,8 @@ void ax25_dev_device_down(struct net_device *dev)
 
 		s = s->next;
 	}
+	spin_unlock_irqrestore(&ax25_dev_lock, flags);
 
-	restore_flags(flags);
 	ax25_register_sysctl();
 }
 
@@ -202,12 +213,17 @@ struct net_device *ax25_fwd_dev(struct net_device *dev)
  */
 void __exit ax25_dev_free(void)
 {
-	ax25_dev *s, *ax25_dev = ax25_dev_list;
+	ax25_dev *s, *ax25_dev;
+	unsigned long flags;
 
+	spin_lock_irqsave(&ax25_dev_lock, flags);
+	ax25_dev = ax25_dev_list;
 	while (ax25_dev != NULL) {
 		s        = ax25_dev;
 		ax25_dev = ax25_dev->next;
 
 		kfree(s);
 	}
+	ax25_dev_list = NULL;
+	spin_unlock_irqrestore(&ax25_dev_lock, flags);
 }

net/ax25/ax25_ds_in.c

@@ -95,11 +95,13 @@ static int ax25_ds_state1_machine(ax25_cb *ax25, struct sk_buff *skb, int framet
 		break;
 
 	case AX25_DM:
-			if (pf) ax25_disconnect(ax25, ECONNREFUSED);
+		if (pf)
+			ax25_disconnect(ax25, ECONNREFUSED);
 		break;
 
 	default:
-			if (pf) ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
+		if (pf)
+			ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
 		break;
 	}
 

net/ax25/ax25_ds_subr.c

@@ -31,6 +31,7 @@
 #include <linux/timer.h>
 #include <linux/string.h>
 #include <linux/sockios.h>
+#include <linux/spinlock.h>
 #include <linux/net.h>
 #include <net/ax25.h>
 #include <linux/inet.h>
@@ -53,6 +54,7 @@ void ax25_ds_nr_error_recovery(ax25_cb *ax25)
  */
 void ax25_ds_enquiry_response(ax25_cb *ax25)
 {
+	unsigned long flags;
 	ax25_cb *ax25o;
 
 	/* Please note that neither DK4EGs nor DG2FEFs
@@ -93,6 +95,7 @@ void ax25_ds_enquiry_response(ax25_cb *ax25)
 	ax25_start_t3timer(ax25);
 	ax25_ds_set_timer(ax25->ax25_dev);
 
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	for (ax25o = ax25_list; ax25o != NULL; ax25o = ax25o->next) {
 		if (ax25o == ax25)
 			continue;
@@ -118,6 +121,7 @@ void ax25_ds_enquiry_response(ax25_cb *ax25)
 		if (ax25o->state != AX25_STATE_0)
 			ax25_start_t3timer(ax25o);
 	}
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 }
 
 void ax25_ds_establish_data_link(ax25_cb *ax25)
@@ -170,13 +174,19 @@ static void ax25_kiss_cmd(ax25_dev *ax25_dev, unsigned char cmd, unsigned char p
  */
 static int ax25_check_dama_slave(ax25_dev *ax25_dev)
 {
+	unsigned long flags;
 	ax25_cb *ax25;
+	int res = 0;
 
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	for (ax25 = ax25_list; ax25 != NULL ; ax25 = ax25->next)
-		if (ax25->ax25_dev == ax25_dev && (ax25->condition & AX25_COND_DAMA_MODE) && ax25->state > AX25_STATE_1)
-			return 1;
+		if (ax25->ax25_dev == ax25_dev && (ax25->condition & AX25_COND_DAMA_MODE) && ax25->state > AX25_STATE_1) {
+			res = 1;
+			break;
+		}
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 
-	return 0;
+	return res;
 }
 
 void ax25_dev_dama_on(ax25_dev *ax25_dev)

net/ax25/ax25_ds_timer.c

@@ -18,6 +18,7 @@
 #include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/socket.h>
+#include <linux/spinlock.h>
 #include <linux/in.h>
 #include <linux/kernel.h>
 #include <linux/jiffies.h>
@@ -79,6 +80,7 @@ void ax25_ds_set_timer(ax25_dev *ax25_dev)
 static void ax25_ds_timeout(unsigned long arg)
 {
 	ax25_dev *ax25_dev = (struct ax25_dev *) arg;
+	unsigned long flags;
 	ax25_cb *ax25;
 	
 	if (ax25_dev == NULL || !ax25_dev->dama.slave)
@@ -89,6 +91,7 @@ static void ax25_ds_timeout(unsigned long arg)
 		return;
 	}
 	
+	spin_lock_irqsave(&ax25_list_lock, flags);
 	for (ax25=ax25_list; ax25 != NULL; ax25 = ax25->next) {
 		if (ax25->ax25_dev != ax25_dev || !(ax25->condition & AX25_COND_DAMA_MODE))
 			continue;
@@ -96,6 +99,7 @@ static void ax25_ds_timeout(unsigned long arg)
 		ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
 		ax25_disconnect(ax25, ETIMEDOUT);
 	}
+	spin_unlock_irqrestore(&ax25_list_lock, flags);
 	
 	ax25_dev_dama_off(ax25_dev);
 }
@@ -178,7 +182,6 @@ void ax25_ds_idletimer_expiry(ax25_cb *ax25)
 void ax25_ds_t1_timeout(ax25_cb *ax25)
 {	
 	switch (ax25->state) {
-
 	case AX25_STATE_1: 
 		if (ax25->n2count == ax25->n2) {
 			if (ax25->modulus == AX25_MODULUS) {

net/ax25/ax25_iface.c

@@ -20,6 +20,7 @@
 #include <linux/in.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
+#include <linux/spinlock.h>
 #include <linux/timer.h>
 #include <linux/string.h>
 #include <linux/sockios.h>
@@ -40,22 +41,24 @@ static struct protocol_struct {
 	unsigned int pid;
 	int (*func)(struct sk_buff *, ax25_cb *);
 } *protocol_list;
+static rwlock_t protocol_list_lock = RW_LOCK_UNLOCKED;
 
 static struct linkfail_struct {
 	struct linkfail_struct *next;
 	void (*func)(ax25_cb *, int);
 } *linkfail_list;
+static spinlock_t linkfail_lock = SPIN_LOCK_UNLOCKED;
 
 static struct listen_struct {
 	struct listen_struct *next;
 	ax25_address  callsign;
 	struct net_device *dev;
 } *listen_list;
+static spinlock_t listen_lock = SPIN_LOCK_UNLOCKED;
 
 int ax25_protocol_register(unsigned int pid, int (*func)(struct sk_buff *, ax25_cb *))
 {
 	struct protocol_struct *protocol;
-	unsigned long flags;
 
 	if (pid == AX25_P_TEXT || pid == AX25_P_SEGMENT)
 		return 0;
@@ -69,31 +72,28 @@ int ax25_protocol_register(unsigned int pid, int (*func)(struct sk_buff *, ax25_
 	protocol->pid  = pid;
 	protocol->func = func;
 
-	save_flags(flags);
-	cli();
-
+	write_lock(&protocol_list_lock);
 	protocol->next = protocol_list;
 	protocol_list  = protocol;
-
-	restore_flags(flags);
+	write_unlock(&protocol_list_lock);
 
 	return 1;
 }
 
 void ax25_protocol_release(unsigned int pid)
 {
-	struct protocol_struct *s, *protocol = protocol_list;
-	unsigned long flags;
+	struct protocol_struct *s, *protocol;
 
-	if (protocol == NULL)
+	write_lock(&protocol_list_lock);
+	protocol = protocol_list;
+	if (protocol == NULL) {
+		write_unlock(&protocol_list_lock);
 		return;
-
-	save_flags(flags);
-	cli();
+	}
 
 	if (protocol->pid == pid) {
 		protocol_list = protocol->next;
-		restore_flags(flags);
+		write_unlock(&protocol_list_lock);
 		kfree(protocol);
 		return;
 	}
@@ -102,15 +102,14 @@ void ax25_protocol_release(unsigned int pid)
 		if (protocol->next->pid == pid) {
 			s = protocol->next;
 			protocol->next = protocol->next->next;
-			restore_flags(flags);
+			write_unlock(&protocol_list_lock);
 			kfree(s);
 			return;
 		}
 
 		protocol = protocol->next;
 	}
-
-	restore_flags(flags);
+	write_unlock(&protocol_list_lock);
 }
 
 int ax25_linkfail_register(void (*func)(ax25_cb *, int))
@@ -123,31 +122,27 @@ int ax25_linkfail_register(void (*func)(ax25_cb *, int))
 
 	linkfail->func = func;
 
-	save_flags(flags);
-	cli();
-
+	spin_lock_irqsave(&linkfail_lock, flags);
 	linkfail->next = linkfail_list;
 	linkfail_list  = linkfail;
-
-	restore_flags(flags);
+	spin_unlock_irqrestore(&linkfail_lock, flags);
 
 	return 1;
 }
 
 void ax25_linkfail_release(void (*func)(ax25_cb *, int))
 {
-	struct linkfail_struct *s, *linkfail = linkfail_list;
+	struct linkfail_struct *s, *linkfail;
 	unsigned long flags;
 
+	spin_lock_irqsave(&linkfail_lock, flags);
+	linkfail = linkfail_list;
 	if (linkfail == NULL)
 		return;
 
-	save_flags(flags);
-	cli();
-
 	if (linkfail->func == func) {
 		linkfail_list = linkfail->next;
-		restore_flags(flags);
+		spin_unlock_irqrestore(&linkfail_lock, flags);
 		kfree(linkfail);
 		return;
 	}
@@ -156,15 +151,14 @@ void ax25_linkfail_release(void (*func)(ax25_cb *, int))
 		if (linkfail->next->func == func) {
 			s = linkfail->next;
 			linkfail->next = linkfail->next->next;
-			restore_flags(flags);
+			spin_unlock_irqrestore(&linkfail_lock, flags);
 			kfree(s);
 			return;
 		}
 
 		linkfail = linkfail->next;
 	}
-
-	restore_flags(flags);
+	spin_unlock_irqrestore(&linkfail_lock, flags);
 }
 
 int ax25_listen_register(ax25_address *callsign, struct net_device *dev)
@@ -181,31 +175,27 @@ int ax25_listen_register(ax25_address *callsign, struct net_device *dev)
 	listen->callsign = *callsign;
 	listen->dev      = dev;
 
-	save_flags(flags);
-	cli();
-
+	spin_lock_irqsave(&listen_lock, flags);
 	listen->next = listen_list;
 	listen_list  = listen;
-
-	restore_flags(flags);
+	spin_unlock_irqrestore(&listen_lock, flags);
 
 	return 1;
 }
 
 void ax25_listen_release(ax25_address *callsign, struct net_device *dev)
 {
-	struct listen_struct *s, *listen = listen_list;
+	struct listen_struct *s, *listen;
 	unsigned long flags;
 
+	spin_lock_irqsave(&listen_lock, flags);
+	listen = listen_list;
 	if (listen == NULL)
 		return;
 
-	save_flags(flags);
-	cli();
-
 	if (ax25cmp(&listen->callsign, callsign) == 0 && listen->dev == dev) {
 		listen_list = listen->next;
-		restore_flags(flags);
+		spin_unlock_irqrestore(&listen_lock, flags);
 		kfree(listen);
 		return;
 	}
@@ -214,35 +204,42 @@ void ax25_listen_release(ax25_address *callsign, struct net_device *dev)
 		if (ax25cmp(&listen->next->callsign, callsign) == 0 && listen->next->dev == dev) {
 			s = listen->next;
 			listen->next = listen->next->next;
-			restore_flags(flags);
+			spin_unlock_irqrestore(&listen_lock, flags);
 			kfree(s);
 			return;
 		}
 
 		listen = listen->next;
 	}
-
-	restore_flags(flags);
+	spin_unlock_irqrestore(&listen_lock, flags);
 }
 
 int (*ax25_protocol_function(unsigned int pid))(struct sk_buff *, ax25_cb *)
 {
+	int (*res)(struct sk_buff *, ax25_cb *) = NULL;
 	struct protocol_struct *protocol;
 
+	read_lock(&protocol_list_lock);
 	for (protocol = protocol_list; protocol != NULL; protocol = protocol->next)
-		if (protocol->pid == pid)
-			return protocol->func;
+		if (protocol->pid == pid) {
+			res = protocol->func;
+			break;
+		}
+	read_unlock(&protocol_list_lock);
 
-	return NULL;
+	return res;
 }
 
 int ax25_listen_mine(ax25_address *callsign, struct net_device *dev)
 {
 	struct listen_struct *listen;
+	unsigned long flags;
 
+	spin_lock_irqsave(&listen_lock, flags);
 	for (listen = listen_list; listen != NULL; listen = listen->next)
 		if (ax25cmp(&listen->callsign, callsign) == 0 && (listen->dev == dev || listen->dev == NULL))
 			return 1;
+	spin_unlock_irqrestore(&listen_lock, flags);
 
 	return 0;
 }
@@ -250,19 +247,26 @@ int ax25_listen_mine(ax25_address *callsign, struct net_device *dev)
 void ax25_link_failed(ax25_cb *ax25, int reason)
 {
 	struct linkfail_struct *linkfail;
+	unsigned long flags;
 
+	spin_lock_irqsave(&linkfail_lock, flags);
 	for (linkfail = linkfail_list; linkfail != NULL; linkfail = linkfail->next)
 		(linkfail->func)(ax25, reason);
+	spin_unlock_irqrestore(&linkfail_lock, flags);
 }
 
 int ax25_protocol_is_registered(unsigned int pid)
 {
 	struct protocol_struct *protocol;
+	int res = 0;
 
+	read_lock(&protocol_list_lock);
 	for (protocol = protocol_list; protocol != NULL; protocol = protocol->next)
-		if (protocol->pid == pid)
-			return 1;
+		if (protocol->pid == pid) {
+			res = 1;
+			break;
+		}
+	read_unlock(&protocol_list_lock);
 
-	return 0;
+	return res;
 }
-

net/ax25/ax25_out.c

@@ -44,6 +44,7 @@
 #include <linux/timer.h>
 #include <linux/string.h>
 #include <linux/sockios.h>
+#include <linux/spinlock.h>
 #include <linux/net.h>
 #include <net/ax25.h>
 #include <linux/inet.h>
@@ -57,6 +58,8 @@
 #include <linux/mm.h>
 #include <linux/interrupt.h>
 
+static spinlock_t ax25_frag_lock = SPIN_LOCK_UNLOCKED;
+
 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_dev *ax25_dev;
@@ -155,11 +158,9 @@ void ax25_output(ax25_cb *ax25, int paclen, struct sk_buff *skb)
 		frontlen = skb_headroom(skb);	/* Address space + CTRL */
 
 		while (skb->len > 0) {
-			save_flags(flags); 
-			cli();
-
+			spin_lock_irqsave(&ax25_frag_lock, flags);
 			if ((skbn = alloc_skb(paclen + 2 + frontlen, GFP_ATOMIC)) == NULL) {
-				restore_flags(flags);
+				spin_unlock_irqrestore(&ax25_frag_lock, flags);
 				printk(KERN_CRIT "AX.25: ax25_output - out of memory\n");
 				return;
 			}
@@ -167,7 +168,7 @@ void ax25_output(ax25_cb *ax25, int paclen, struct sk_buff *skb)
 			if (skb->sk != NULL)
 				skb_set_owner_w(skbn, skb->sk);
 			
-			restore_flags(flags);
+			spin_unlock_irqrestore(&ax25_frag_lock, flags);
 			
 			len = (paclen > skb->len) ? skb->len : paclen;
 

net/ax25/ax25_route.c

@@ -56,6 +56,7 @@
 #include <linux/netdevice.h>
 #include <linux/if_arp.h>
 #include <linux/skbuff.h>
+#include <linux/spinlock.h>
 #include <net/sock.h>
 #include <asm/uaccess.h>
 #include <asm/system.h>
@@ -65,6 +66,7 @@
 #include <linux/init.h>
 
 static ax25_route *ax25_route_list;
+static rwlock_t ax25_route_lock = RW_LOCK_UNLOCKED;
 
 static ax25_route *ax25_find_route(ax25_address *, struct net_device *);
 
@@ -86,8 +88,10 @@ static inline void ax25_route_invert(ax25_digi *in, ax25_digi *out)
 
 void ax25_rt_device_down(struct net_device *dev)
 {
-	ax25_route *s, *t, *ax25_rt = ax25_route_list;
+	ax25_route *s, *t, *ax25_rt;
 
+	write_lock(&ax25_route_lock);
+	ax25_rt = ax25_route_list;
 	while (ax25_rt != NULL) {
 		s       = ax25_rt;
 		ax25_rt = ax25_rt->next;
@@ -111,11 +115,11 @@ void ax25_rt_device_down(struct net_device *dev)
 			}
 		}
 	}
+	write_unlock(&ax25_route_lock);
 }
 
 int ax25_rt_ioctl(unsigned int cmd, void *arg)
 {
-	unsigned long flags;
 	ax25_route *s, *t, *ax25_rt;
 	struct ax25_routes_struct route;
 	struct ax25_route_opt_struct rt_option;
@@ -130,6 +134,7 @@ int ax25_rt_ioctl(unsigned int cmd, void *arg)
 			return -EINVAL;
 		if (route.digi_count > AX25_MAX_DIGIS)
 			return -EINVAL;
+		write_lock(ax25_route_lock);
 		for (ax25_rt = ax25_route_list; ax25_rt != NULL; ax25_rt = ax25_rt->next) {
 			if (ax25cmp(&ax25_rt->callsign, &route.dest_addr) == 0 && ax25_rt->dev == ax25_dev->dev) {
 				if (ax25_rt->digipeat != NULL) {
@@ -137,8 +142,10 @@ int ax25_rt_ioctl(unsigned int cmd, void *arg)
 					ax25_rt->digipeat = NULL;
 				}
 				if (route.digi_count != 0) {
-						if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL)
+					if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) {
+						write_unlock(ax25_route_lock);
 						return -ENOMEM;
+					}
 					ax25_rt->digipeat->lastrepeat = -1;
 					ax25_rt->digipeat->ndigi      = route.digi_count;
 					for (i = 0; i < route.digi_count; i++) {
@@ -149,14 +156,17 @@ int ax25_rt_ioctl(unsigned int cmd, void *arg)
 				return 0;
 			}
 		}
-			if ((ax25_rt = kmalloc(sizeof(ax25_route), GFP_ATOMIC)) == NULL)
+		if ((ax25_rt = kmalloc(sizeof(ax25_route), GFP_ATOMIC)) == NULL) {
+			write_unlock(ax25_route_lock);
 			return -ENOMEM;
+		}
 		ax25_rt->callsign     = route.dest_addr;
 		ax25_rt->dev          = ax25_dev->dev;
 		ax25_rt->digipeat     = NULL;
 		ax25_rt->ip_mode      = ' ';
 		if (route.digi_count != 0) {
 			if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) {
+				write_unlock(ax25_route_lock);
 				kfree(ax25_rt);
 				return -ENOMEM;
 			}
@@ -167,10 +177,10 @@ int ax25_rt_ioctl(unsigned int cmd, void *arg)
 				ax25_rt->digipeat->calls[i]    = route.digi_addr[i];
 			}
 		}
-			save_flags(flags); cli();
 		ax25_rt->next   = ax25_route_list;
 		ax25_route_list = ax25_rt;
-			restore_flags(flags);
+		write_unlock(ax25_route_lock);
+
 		break;
 
 	case SIOCDELRT:
@@ -208,6 +218,7 @@ int ax25_rt_ioctl(unsigned int cmd, void *arg)
 			return -EFAULT;
 		if ((ax25_dev = ax25_addr_ax25dev(&rt_option.port_addr)) == NULL)
 			return -EINVAL;
+		write_lock(ax25_route_lock);
 		for (ax25_rt = ax25_route_list; ax25_rt != NULL; ax25_rt = ax25_rt->next) {
 			if (ax25_rt->dev == ax25_dev->dev && ax25cmp(&rt_option.dest_addr, &ax25_rt->callsign) == 0) {
 				switch (rt_option.cmd) {
@@ -227,6 +238,7 @@ int ax25_rt_ioctl(unsigned int cmd, void *arg)
 				}
 			}
 		}
+		write_unlock(ax25_route_lock);
 		break;
 
 	default:
@@ -245,7 +257,7 @@ int ax25_rt_get_info(char *buffer, char **start, off_t offset, int length)
 	char *callsign;
 	int i;
   
-	cli();
+	read_lock(&ax25_route_lock);
 
 	len += sprintf(buffer, "callsign  dev  mode digipeaters\n");
 
@@ -286,13 +298,13 @@ int ax25_rt_get_info(char *buffer, char **start, off_t offset, int length)
 		if (pos > offset + length)
 			break;
 	}
-
-	sti();
+	read_unlock(&ax25_route_lock);
 
 	*start = buffer + (offset - begin);
 	len   -= (offset - begin);
 
-	if (len > length) len = length;
+	if (len > length)
+		len = length;
 
 	return len;
 } 
@@ -306,6 +318,7 @@ static ax25_route *ax25_find_route(ax25_address *addr, struct net_device *dev)
 	ax25_route *ax25_def_rt = NULL;
 	ax25_route *ax25_rt;
 
+	read_lock(&ax25_route_lock);
 	/*
 	 *	Bind to the physical interface we heard them on, or the default
 	 *	route if none is found;
@@ -323,6 +336,7 @@ static ax25_route *ax25_find_route(ax25_address *addr, struct net_device *dev)
 				ax25_def_rt = ax25_rt;
 		}
 	}
+	read_unlock(&ax25_route_lock);
 
 	if (ax25_spe_rt != NULL)
 		return ax25_spe_rt;
@@ -440,6 +454,7 @@ void __exit ax25_rt_free(void)
 {
 	ax25_route *s, *ax25_rt = ax25_route_list;
 
+	write_unlock(&ax25_route_lock);
 	while (ax25_rt != NULL) {
 		s       = ax25_rt;
 		ax25_rt = ax25_rt->next;
@@ -449,4 +464,5 @@ void __exit ax25_rt_free(void)
 
 		kfree(s);
 	}
+	write_unlock(&ax25_route_lock);
 }

net/ax25/ax25_std_in.c

@@ -142,7 +142,8 @@ static int ax25_std_state2_machine(ax25_cb *ax25, struct sk_buff *skb, int frame
 
 	case AX25_DM:
 	case AX25_UA:
-			if (pf) ax25_disconnect(ax25, 0);
+		if (pf)
+			ax25_disconnect(ax25, 0);
 		break;
 
 	case AX25_I:
@@ -397,7 +398,8 @@ static int ax25_std_state4_machine(ax25_cb *ax25, struct sk_buff *skb, int frame
 		}
 		ax25_frames_acked(ax25, nr);
 		if (ax25->condition & AX25_COND_OWN_RX_BUSY) {
-				if (pf) ax25_std_enquiry_response(ax25);
+			if (pf)
+				ax25_std_enquiry_response(ax25);
 			break;
 		}
 		if (ns == ax25->vr) {

net/ax25/ax25_std_timer.c

@@ -47,7 +47,6 @@
 void ax25_std_heartbeat_expiry(ax25_cb *ax25)
 {
 	switch (ax25->state) {
-
 	case AX25_STATE_0:
 		/* Magic here: If we listen() and a new link dies before it
 		   is accepted() it isn't 'dead' so doesn't get removed. */

net/ax25/ax25_uid.c

@@ -23,6 +23,7 @@
 #include <linux/string.h>
 #include <linux/sockios.h>
 #include <linux/net.h>
+#include <linux/spinlock.h>
 #include <net/ax25.h>
 #include <linux/inet.h>
 #include <linux/netdevice.h>
@@ -47,17 +48,23 @@
  */
 
 static ax25_uid_assoc *ax25_uid_list;
+static rwlock_t ax25_uid_lock = RW_LOCK_UNLOCKED;
 
 int ax25_uid_policy = 0;
 
 ax25_address *ax25_findbyuid(uid_t uid)
 {
 	ax25_uid_assoc *ax25_uid;
+	ax25_address *res = NULL;
 
+	read_lock(&ax25_uid_lock);
 	for (ax25_uid = ax25_uid_list; ax25_uid != NULL; ax25_uid = ax25_uid->next) {
-		if (ax25_uid->uid == uid)
-			return &ax25_uid->call;
+		if (ax25_uid->uid == uid) {
+			res = &ax25_uid->call;
+			break;
+		}
 	}
+	read_unlock(&ax25_uid_lock);
 
 	return NULL;
 }
@@ -65,15 +72,21 @@ ax25_address *ax25_findbyuid(uid_t uid)
 int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
 {
 	ax25_uid_assoc *s, *ax25_uid;
-	unsigned long flags;
+	unsigned long res;
 
 	switch (cmd) {
 	case SIOCAX25GETUID:
+		res = -ENOENT;
+		read_lock(&ax25_uid_lock);
 		for (ax25_uid = ax25_uid_list; ax25_uid != NULL; ax25_uid = ax25_uid->next) {
-				if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0)
-					return ax25_uid->uid;
+			if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0) {
+				res = ax25_uid->uid;
+				break;
 			}
-			return -ENOENT;
+		}
+		read_unlock(&ax25_uid_lock);
+
+		return res;
 
 	case SIOCAX25ADDUID:
 		if (!capable(CAP_NET_ADMIN))
@@ -84,40 +97,48 @@ int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
 			return -EINVAL;
 		if ((ax25_uid = kmalloc(sizeof(*ax25_uid), GFP_KERNEL)) == NULL)
 			return -ENOMEM;
+
 		ax25_uid->uid  = sax->sax25_uid;
 		ax25_uid->call = sax->sax25_call;
-			save_flags(flags); cli();
+
+		write_lock(&ax25_uid_lock);
 		ax25_uid->next = ax25_uid_list;
 		ax25_uid_list  = ax25_uid;
-			restore_flags(flags);
+		write_unlock(&ax25_uid_lock);
+
 		return 0;
 
 	case SIOCAX25DELUID:
 		if (!capable(CAP_NET_ADMIN))
 			return -EPERM;
+
+		write_lock(&ax25_uid_lock);
 		for (ax25_uid = ax25_uid_list; ax25_uid != NULL; ax25_uid = ax25_uid->next) {
-				if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0)
+			if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0) {
 				break;
 			}
-			if (ax25_uid == NULL)
+		}
+		if (ax25_uid == NULL) {
+			write_unlock(&ax25_uid_lock);
 			return -ENOENT;
-			save_flags(flags); cli();
+		}
 		if ((s = ax25_uid_list) == ax25_uid) {
 			ax25_uid_list = s->next;
-				restore_flags(flags);
+			write_unlock(&ax25_uid_lock);
 			kfree(ax25_uid);
 			return 0;
 		}
 		while (s != NULL && s->next != NULL) {
 			if (s->next == ax25_uid) {
 				s->next = ax25_uid->next;
-					restore_flags(flags);
+				write_unlock(&ax25_uid_lock);
 				kfree(ax25_uid);
 				return 0;
 			}
 			s = s->next;
 		}
-			restore_flags(flags);
+		write_unlock(&ax25_uid_lock);
+
 		return -ENOENT;
 
 	default:
@@ -134,8 +155,7 @@ int ax25_uid_get_info(char *buffer, char **start, off_t offset, int length)
 	off_t pos   = 0;
 	off_t begin = 0;
 
-	cli();
-
+	read_lock(&ax25_uid_lock);
 	len += sprintf(buffer, "Policy: %d\n", ax25_uid_policy);
 
 	for (pt = ax25_uid_list; pt != NULL; pt = pt->next) {
@@ -151,13 +171,13 @@ int ax25_uid_get_info(char *buffer, char **start, off_t offset, int length)
 		if (pos > offset + length)
 			break;
 	}
-
-	sti();
+	read_unlock(&ax25_uid_lock);
 
 	*start = buffer + (offset - begin);
 	len   -= offset - begin;
 
-	if (len > length) len = length;
+	if (len > length)
+		len = length;
 
 	return len;
 }
@@ -167,12 +187,16 @@ int ax25_uid_get_info(char *buffer, char **start, off_t offset, int length)
  */
 void __exit ax25_uid_free(void)
 {
-	ax25_uid_assoc *s, *ax25_uid = ax25_uid_list;
+	ax25_uid_assoc *s, *ax25_uid;
 
+	write_lock(&ax25_uid_lock);
+	ax25_uid = ax25_uid_list;
 	while (ax25_uid != NULL) {
 		s        = ax25_uid;
 		ax25_uid = ax25_uid->next;
 
 		kfree(s);
 	}
+	ax25_uid_list = NULL;
+	write_unlock(&ax25_uid_lock);
 }

net/ax25/sysctl_net_ax25.c

@@ -8,6 +8,7 @@
 #include <linux/config.h>
 #include <linux/mm.h>
 #include <linux/sysctl.h>
+#include <linux/spinlock.h>
 #include <net/ax25.h>
 
 static int min_ipdefmode[] = {0},	max_ipdefmode[] = {1};
@@ -102,9 +103,11 @@ static const ctl_table ax25_param_table[] = {
 
 void ax25_register_sysctl(void)
 {
+	unsigned long flags;
 	ax25_dev *ax25_dev;
 	int n, k;
 
+	spin_lock_irqsave(&ax25_dev_lock, flags);
 	for (ax25_table_size = sizeof(ctl_table), ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next)
 		ax25_table_size += sizeof(ctl_table);
 
@@ -119,6 +122,7 @@ void ax25_register_sysctl(void)
 			while (n--)
 				kfree(ax25_table[n].child);
 			kfree(ax25_table);
+			spin_unlock_irqrestore(&ax25_dev_lock, flags);
 			return;
 		}
 		memcpy(child, ax25_param_table, sizeof(ax25_param_table));
@@ -144,6 +148,7 @@ void ax25_register_sysctl(void)
 
 		n++;
 	}
+	spin_unlock_irqrestore(&ax25_dev_lock, flags);
 
 	ax25_dir_table[0].child = ax25_table;