[AX.25]: Fix potencial memory hole.
[linux-2.6.git] / net / ax25 / sysctl_net_ax25.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) 1996 Mike Shaver (shaver@zeroknowledge.com)
8  */
9 #include <linux/config.h>
10 #include <linux/mm.h>
11 #include <linux/sysctl.h>
12 #include <linux/spinlock.h>
13 #include <net/ax25.h>
14
15 static int min_ipdefmode[1],            max_ipdefmode[] = {1};
16 static int min_axdefmode[1],            max_axdefmode[] = {1};
17 static int min_backoff[1],              max_backoff[] = {2};
18 static int min_conmode[1],              max_conmode[] = {2};
19 static int min_window[] = {1},          max_window[] = {7};
20 static int min_ewindow[] = {1},         max_ewindow[] = {63};
21 static int min_t1[] = {1},              max_t1[] = {30 * HZ};
22 static int min_t2[] = {1},              max_t2[] = {20 * HZ};
23 static int min_t3[1],                   max_t3[] = {3600 * HZ};
24 static int min_idle[1],                 max_idle[] = {65535 * HZ};
25 static int min_n2[] = {1},              max_n2[] = {31};
26 static int min_paclen[] = {1},          max_paclen[] = {512};
27 static int min_proto[1],                max_proto[] = { AX25_PROTO_MAX };
28 static int min_ds_timeout[1],           max_ds_timeout[] = {65535 * HZ};
29
30 static struct ctl_table_header *ax25_table_header;
31
32 static ctl_table *ax25_table;
33 static int ax25_table_size;
34
35 static ctl_table ax25_dir_table[] = {
36         {
37                 .ctl_name       = NET_AX25,
38                 .procname       = "ax25",
39                 .mode           = 0555,
40         },
41         { .ctl_name = 0 }
42 };
43
44 static ctl_table ax25_root_table[] = {
45         {
46                 .ctl_name       = CTL_NET,
47                 .procname       = "net",
48                 .mode           = 0555,
49                 .child          = ax25_dir_table
50         },
51         { .ctl_name = 0 }
52 };
53
54 static const ctl_table ax25_param_table[] = {
55         {
56                 .ctl_name       = NET_AX25_IP_DEFAULT_MODE,
57                 .procname       = "ip_default_mode",
58                 .maxlen         = sizeof(int),
59                 .mode           = 0644,
60                 .proc_handler   = &proc_dointvec_minmax,
61                 .strategy       = &sysctl_intvec,
62                 .extra1         = &min_ipdefmode,
63                 .extra2         = &max_ipdefmode
64         },
65         {
66                 .ctl_name       = NET_AX25_DEFAULT_MODE,
67                 .procname       = "ax25_default_mode",
68                 .maxlen         = sizeof(int),
69                 .mode           = 0644,
70                 .proc_handler   = &proc_dointvec_minmax,
71                 .strategy       = &sysctl_intvec,
72                 .extra1         = &min_axdefmode,
73                 .extra2         = &max_axdefmode
74         },
75         {
76                 .ctl_name       = NET_AX25_BACKOFF_TYPE,
77                 .procname       = "backoff_type",
78                 .maxlen         = sizeof(int),
79                 .mode           = 0644,
80                 .proc_handler   = &proc_dointvec_minmax,
81                 .strategy       = &sysctl_intvec,
82                 .extra1         = &min_backoff,
83                 .extra2         = &max_backoff
84         },
85         {
86                 .ctl_name       = NET_AX25_CONNECT_MODE,
87                 .procname       = "connect_mode",
88                 .maxlen         = sizeof(int),
89                 .mode           = 0644,
90                 .proc_handler   = &proc_dointvec_minmax,
91                 .strategy       = &sysctl_intvec,
92                 .extra1         = &min_conmode,
93                 .extra2         = &max_conmode
94         },
95         {
96                 .ctl_name       = NET_AX25_STANDARD_WINDOW,
97                 .procname       = "standard_window_size",
98                 .maxlen         = sizeof(int),
99                 .mode           = 0644,
100                 .proc_handler   = &proc_dointvec_minmax,
101                 .strategy       = &sysctl_intvec,
102                 .extra1         = &min_window,
103                 .extra2         = &max_window
104         },
105         {
106                 .ctl_name       = NET_AX25_EXTENDED_WINDOW,
107                 .procname       = "extended_window_size",
108                 .maxlen         = sizeof(int),
109                 .mode           = 0644,
110                 .proc_handler   = &proc_dointvec_minmax,
111                 .strategy       = &sysctl_intvec,
112                 .extra1         = &min_ewindow,
113                 .extra2         = &max_ewindow
114         },
115         {
116                 .ctl_name       = NET_AX25_T1_TIMEOUT,
117                 .procname       = "t1_timeout",
118                 .maxlen         = sizeof(int),
119                 .mode           = 0644,
120                 .proc_handler   = &proc_dointvec_minmax,
121                 .strategy       = &sysctl_intvec,
122                 .extra1         = &min_t1,
123                 .extra2         = &max_t1
124         },
125         {
126                 .ctl_name       = NET_AX25_T2_TIMEOUT,
127                 .procname       = "t2_timeout",
128                 .maxlen         = sizeof(int),
129                 .mode           = 0644,
130                 .proc_handler   = &proc_dointvec_minmax,
131                 .strategy       = &sysctl_intvec,
132                 .extra1         = &min_t2,
133                 .extra2         = &max_t2
134         },
135         {
136                 .ctl_name       = NET_AX25_T3_TIMEOUT,
137                 .procname       = "t3_timeout",
138                 .maxlen         = sizeof(int),
139                 .mode           = 0644,
140                 .proc_handler   = &proc_dointvec_minmax,
141                 .strategy       = &sysctl_intvec,
142                 .extra1         = &min_t3,
143                 .extra2         = &max_t3
144         },
145         {
146                 .ctl_name       = NET_AX25_IDLE_TIMEOUT,
147                 .procname       = "idle_timeout",
148                 .maxlen         = sizeof(int),
149                 .mode           = 0644,
150                 .proc_handler   = &proc_dointvec_minmax,
151                 .strategy       = &sysctl_intvec,
152                 .extra1         = &min_idle,
153                 .extra2         = &max_idle
154         },
155         {
156                 .ctl_name       = NET_AX25_N2,
157                 .procname       = "maximum_retry_count",
158                 .maxlen         = sizeof(int),
159                 .mode           = 0644,
160                 .proc_handler   = &proc_dointvec_minmax,
161                 .strategy       = &sysctl_intvec,
162                 .extra1         = &min_n2,
163                 .extra2         = &max_n2
164         },
165         {
166                 .ctl_name       = NET_AX25_PACLEN,
167                 .procname       = "maximum_packet_length",
168                 .maxlen         = sizeof(int),
169                 .mode           = 0644,
170                 .proc_handler   = &proc_dointvec_minmax,
171                 .strategy       = &sysctl_intvec,
172                 .extra1         = &min_paclen,
173                 .extra2         = &max_paclen
174         },
175         {
176                 .ctl_name       = NET_AX25_PROTOCOL,
177                 .procname       = "protocol",
178                 .maxlen         = sizeof(int),
179                 .mode           = 0644,
180                 .proc_handler   = &proc_dointvec_minmax,
181                 .strategy       = &sysctl_intvec,
182                 .extra1         = &min_proto,
183                 .extra2         = &max_proto
184         },
185         {
186                 .ctl_name       = NET_AX25_DAMA_SLAVE_TIMEOUT,
187                 .procname       = "dama_slave_timeout",
188                 .maxlen         = sizeof(int),
189                 .mode           = 0644,
190                 .proc_handler   = &proc_dointvec_minmax,
191                 .strategy       = &sysctl_intvec,
192                 .extra1         = &min_ds_timeout,
193                 .extra2         = &max_ds_timeout
194         },
195         { .ctl_name = 0 }       /* that's all, folks! */
196 };
197
198 void ax25_register_sysctl(void)
199 {
200         ax25_dev *ax25_dev;
201         int n, k;
202
203         spin_lock_bh(&ax25_dev_lock);
204         for (ax25_table_size = sizeof(ctl_table), ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next)
205                 ax25_table_size += sizeof(ctl_table);
206
207         if ((ax25_table = kmalloc(ax25_table_size, GFP_ATOMIC)) == NULL) {
208                 spin_unlock_bh(&ax25_dev_lock);
209                 return;
210         }
211
212         memset(ax25_table, 0x00, ax25_table_size);
213
214         for (n = 0, ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next) {
215                 ctl_table *child = kmalloc(sizeof(ax25_param_table), GFP_ATOMIC);
216                 if (!child) {
217                         while (n--)
218                                 kfree(ax25_table[n].child);
219                         kfree(ax25_table);
220                         spin_unlock_bh(&ax25_dev_lock);
221                         return;
222                 }
223                 memcpy(child, ax25_param_table, sizeof(ax25_param_table));
224                 ax25_table[n].child = ax25_dev->systable = child;
225                 ax25_table[n].ctl_name     = n + 1;
226                 ax25_table[n].procname     = ax25_dev->dev->name;
227                 ax25_table[n].mode         = 0555;
228
229 #ifndef CONFIG_AX25_DAMA_SLAVE
230                 /*
231                  * We do not wish to have a representation of this parameter
232                  * in /proc/sys/ when configured *not* to include the
233                  * AX.25 DAMA slave code, do we?
234                  */
235
236                 child[AX25_VALUES_DS_TIMEOUT].procname = NULL;
237 #endif
238
239                 child[AX25_MAX_VALUES].ctl_name = 0;    /* just in case... */
240
241                 for (k = 0; k < AX25_MAX_VALUES; k++)
242                         child[k].data = &ax25_dev->values[k];
243
244                 n++;
245         }
246         spin_unlock_bh(&ax25_dev_lock);
247
248         ax25_dir_table[0].child = ax25_table;
249
250         ax25_table_header = register_sysctl_table(ax25_root_table, 1);
251 }
252
253 void ax25_unregister_sysctl(void)
254 {
255         ctl_table *p;
256         unregister_sysctl_table(ax25_table_header);
257
258         ax25_dir_table[0].child = NULL;
259         for (p = ax25_table; p->ctl_name; p++)
260                 kfree(p->child);
261         kfree(ax25_table);
262 }