Staging: prevent rtl8192su from crashing dev_ioctl in SIOCGIWNAME
[linux-2.6] / net / ax25 / ax25_dev.c
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License as published by
4  * the Free Software Foundation; either version 2 of the License, or
5  * (at your option) any later version.
6  *
7  * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8  */
9 #include <linux/errno.h>
10 #include <linux/types.h>
11 #include <linux/socket.h>
12 #include <linux/in.h>
13 #include <linux/kernel.h>
14 #include <linux/timer.h>
15 #include <linux/string.h>
16 #include <linux/sockios.h>
17 #include <linux/net.h>
18 #include <linux/spinlock.h>
19 #include <net/ax25.h>
20 #include <linux/inet.h>
21 #include <linux/netdevice.h>
22 #include <linux/if_arp.h>
23 #include <linux/skbuff.h>
24 #include <net/sock.h>
25 #include <asm/uaccess.h>
26 #include <asm/system.h>
27 #include <linux/fcntl.h>
28 #include <linux/mm.h>
29 #include <linux/interrupt.h>
30 #include <linux/init.h>
31
32 ax25_dev *ax25_dev_list;
33 DEFINE_SPINLOCK(ax25_dev_lock);
34
35 ax25_dev *ax25_addr_ax25dev(ax25_address *addr)
36 {
37         ax25_dev *ax25_dev, *res = NULL;
38
39         spin_lock_bh(&ax25_dev_lock);
40         for (ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next)
41                 if (ax25cmp(addr, (ax25_address *)ax25_dev->dev->dev_addr) == 0) {
42                         res = ax25_dev;
43                 }
44         spin_unlock_bh(&ax25_dev_lock);
45
46         return res;
47 }
48
49 /*
50  *      This is called when an interface is brought up. These are
51  *      reasonable defaults.
52  */
53 void ax25_dev_device_up(struct net_device *dev)
54 {
55         ax25_dev *ax25_dev;
56
57         if ((ax25_dev = kzalloc(sizeof(*ax25_dev), GFP_ATOMIC)) == NULL) {
58                 printk(KERN_ERR "AX.25: ax25_dev_device_up - out of memory\n");
59                 return;
60         }
61
62         ax25_unregister_sysctl();
63
64         dev->ax25_ptr     = ax25_dev;
65         ax25_dev->dev     = dev;
66         dev_hold(dev);
67         ax25_dev->forward = NULL;
68
69         ax25_dev->values[AX25_VALUES_IPDEFMODE] = AX25_DEF_IPDEFMODE;
70         ax25_dev->values[AX25_VALUES_AXDEFMODE] = AX25_DEF_AXDEFMODE;
71         ax25_dev->values[AX25_VALUES_BACKOFF]   = AX25_DEF_BACKOFF;
72         ax25_dev->values[AX25_VALUES_CONMODE]   = AX25_DEF_CONMODE;
73         ax25_dev->values[AX25_VALUES_WINDOW]    = AX25_DEF_WINDOW;
74         ax25_dev->values[AX25_VALUES_EWINDOW]   = AX25_DEF_EWINDOW;
75         ax25_dev->values[AX25_VALUES_T1]        = AX25_DEF_T1;
76         ax25_dev->values[AX25_VALUES_T2]        = AX25_DEF_T2;
77         ax25_dev->values[AX25_VALUES_T3]        = AX25_DEF_T3;
78         ax25_dev->values[AX25_VALUES_IDLE]      = AX25_DEF_IDLE;
79         ax25_dev->values[AX25_VALUES_N2]        = AX25_DEF_N2;
80         ax25_dev->values[AX25_VALUES_PACLEN]    = AX25_DEF_PACLEN;
81         ax25_dev->values[AX25_VALUES_PROTOCOL]  = AX25_DEF_PROTOCOL;
82         ax25_dev->values[AX25_VALUES_DS_TIMEOUT]= AX25_DEF_DS_TIMEOUT;
83
84 #if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER)
85         ax25_ds_setup_timer(ax25_dev);
86 #endif
87
88         spin_lock_bh(&ax25_dev_lock);
89         ax25_dev->next = ax25_dev_list;
90         ax25_dev_list  = ax25_dev;
91         spin_unlock_bh(&ax25_dev_lock);
92
93         ax25_register_sysctl();
94 }
95
96 void ax25_dev_device_down(struct net_device *dev)
97 {
98         ax25_dev *s, *ax25_dev;
99
100         if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
101                 return;
102
103         ax25_unregister_sysctl();
104
105         spin_lock_bh(&ax25_dev_lock);
106
107 #ifdef CONFIG_AX25_DAMA_SLAVE
108         ax25_ds_del_timer(ax25_dev);
109 #endif
110
111         /*
112          *      Remove any packet forwarding that points to this device.
113          */
114         for (s = ax25_dev_list; s != NULL; s = s->next)
115                 if (s->forward == dev)
116                         s->forward = NULL;
117
118         if ((s = ax25_dev_list) == ax25_dev) {
119                 ax25_dev_list = s->next;
120                 spin_unlock_bh(&ax25_dev_lock);
121                 dev_put(dev);
122                 kfree(ax25_dev);
123                 ax25_register_sysctl();
124                 return;
125         }
126
127         while (s != NULL && s->next != NULL) {
128                 if (s->next == ax25_dev) {
129                         s->next = ax25_dev->next;
130                         spin_unlock_bh(&ax25_dev_lock);
131                         dev_put(dev);
132                         kfree(ax25_dev);
133                         ax25_register_sysctl();
134                         return;
135                 }
136
137                 s = s->next;
138         }
139         spin_unlock_bh(&ax25_dev_lock);
140         dev->ax25_ptr = NULL;
141
142         ax25_register_sysctl();
143 }
144
145 int ax25_fwd_ioctl(unsigned int cmd, struct ax25_fwd_struct *fwd)
146 {
147         ax25_dev *ax25_dev, *fwd_dev;
148
149         if ((ax25_dev = ax25_addr_ax25dev(&fwd->port_from)) == NULL)
150                 return -EINVAL;
151
152         switch (cmd) {
153         case SIOCAX25ADDFWD:
154                 if ((fwd_dev = ax25_addr_ax25dev(&fwd->port_to)) == NULL)
155                         return -EINVAL;
156                 if (ax25_dev->forward != NULL)
157                         return -EINVAL;
158                 ax25_dev->forward = fwd_dev->dev;
159                 break;
160
161         case SIOCAX25DELFWD:
162                 if (ax25_dev->forward == NULL)
163                         return -EINVAL;
164                 ax25_dev->forward = NULL;
165                 break;
166
167         default:
168                 return -EINVAL;
169         }
170
171         return 0;
172 }
173
174 struct net_device *ax25_fwd_dev(struct net_device *dev)
175 {
176         ax25_dev *ax25_dev;
177
178         if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
179                 return dev;
180
181         if (ax25_dev->forward == NULL)
182                 return dev;
183
184         return ax25_dev->forward;
185 }
186
187 /*
188  *      Free all memory associated with device structures.
189  */
190 void __exit ax25_dev_free(void)
191 {
192         ax25_dev *s, *ax25_dev;
193
194         spin_lock_bh(&ax25_dev_lock);
195         ax25_dev = ax25_dev_list;
196         while (ax25_dev != NULL) {
197                 s        = ax25_dev;
198                 dev_put(ax25_dev->dev);
199                 ax25_dev = ax25_dev->next;
200                 kfree(s);
201         }
202         ax25_dev_list = NULL;
203         spin_unlock_bh(&ax25_dev_lock);
204 }