Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2007 |
| 3 | * |
| 4 | * Author: Eric Biederman <ebiederm@xmision.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License as |
| 8 | * published by the Free Software Foundation, version 2 of the |
| 9 | * License. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/ipc.h> |
| 14 | #include <linux/nsproxy.h> |
| 15 | #include <linux/sysctl.h> |
| 16 | #include <linux/uaccess.h> |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 17 | #include <linux/ipc_namespace.h> |
Nadia Derbey | 6546bc4 | 2008-04-29 01:00:45 -0700 | [diff] [blame] | 18 | #include <linux/msg.h> |
| 19 | #include "util.h" |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 20 | |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 21 | static void *get_ipc(ctl_table *table) |
| 22 | { |
| 23 | char *which = table->data; |
| 24 | struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns; |
| 25 | which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns; |
| 26 | return which; |
| 27 | } |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 28 | |
| 29 | #ifdef CONFIG_PROC_FS |
| 30 | static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp, |
| 31 | void __user *buffer, size_t *lenp, loff_t *ppos) |
| 32 | { |
| 33 | struct ctl_table ipc_table; |
| 34 | memcpy(&ipc_table, table, sizeof(ipc_table)); |
| 35 | ipc_table.data = get_ipc(table); |
| 36 | |
| 37 | return proc_dointvec(&ipc_table, write, filp, buffer, lenp, ppos); |
| 38 | } |
| 39 | |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 40 | static int proc_ipc_callback_dointvec(ctl_table *table, int write, |
| 41 | struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) |
| 42 | { |
Nadia Derbey | 6546bc4 | 2008-04-29 01:00:45 -0700 | [diff] [blame] | 43 | struct ctl_table ipc_table; |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 44 | size_t lenp_bef = *lenp; |
| 45 | int rc; |
| 46 | |
Nadia Derbey | 6546bc4 | 2008-04-29 01:00:45 -0700 | [diff] [blame] | 47 | memcpy(&ipc_table, table, sizeof(ipc_table)); |
| 48 | ipc_table.data = get_ipc(table); |
| 49 | |
| 50 | rc = proc_dointvec(&ipc_table, write, filp, buffer, lenp, ppos); |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 51 | |
| 52 | if (write && !rc && lenp_bef == *lenp) |
Nadia Derbey | 9eefe52 | 2008-07-25 01:48:08 -0700 | [diff] [blame] | 53 | /* |
| 54 | * Tunable has successfully been changed by hand. Disable its |
| 55 | * automatic adjustment. This simply requires unregistering |
| 56 | * the notifiers that trigger recalculation. |
| 57 | */ |
| 58 | unregister_ipcns_notifier(current->nsproxy->ipc_ns); |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 59 | |
| 60 | return rc; |
| 61 | } |
| 62 | |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 63 | static int proc_ipc_doulongvec_minmax(ctl_table *table, int write, |
| 64 | struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) |
| 65 | { |
| 66 | struct ctl_table ipc_table; |
| 67 | memcpy(&ipc_table, table, sizeof(ipc_table)); |
| 68 | ipc_table.data = get_ipc(table); |
| 69 | |
| 70 | return proc_doulongvec_minmax(&ipc_table, write, filp, buffer, |
| 71 | lenp, ppos); |
| 72 | } |
| 73 | |
akpm@linux-foundation.org | 4c2c3b4 | 2009-01-06 14:42:51 -0800 | [diff] [blame^] | 74 | /* |
| 75 | * Routine that is called when the file "auto_msgmni" has successfully been |
| 76 | * written. |
| 77 | * Two values are allowed: |
| 78 | * 0: unregister msgmni's callback routine from the ipc namespace notifier |
| 79 | * chain. This means that msgmni won't be recomputed anymore upon memory |
| 80 | * add/remove or ipc namespace creation/removal. |
| 81 | * 1: register back the callback routine. |
| 82 | */ |
| 83 | static void ipc_auto_callback(int val) |
| 84 | { |
| 85 | if (!val) |
| 86 | unregister_ipcns_notifier(current->nsproxy->ipc_ns); |
| 87 | else { |
| 88 | /* |
| 89 | * Re-enable automatic recomputing only if not already |
| 90 | * enabled. |
| 91 | */ |
| 92 | recompute_msgmni(current->nsproxy->ipc_ns); |
| 93 | cond_register_ipcns_notifier(current->nsproxy->ipc_ns); |
| 94 | } |
| 95 | } |
| 96 | |
Nadia Derbey | 9eefe52 | 2008-07-25 01:48:08 -0700 | [diff] [blame] | 97 | static int proc_ipcauto_dointvec_minmax(ctl_table *table, int write, |
| 98 | struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) |
| 99 | { |
| 100 | struct ctl_table ipc_table; |
| 101 | size_t lenp_bef = *lenp; |
| 102 | int oldval; |
| 103 | int rc; |
| 104 | |
| 105 | memcpy(&ipc_table, table, sizeof(ipc_table)); |
| 106 | ipc_table.data = get_ipc(table); |
| 107 | oldval = *((int *)(ipc_table.data)); |
| 108 | |
| 109 | rc = proc_dointvec_minmax(&ipc_table, write, filp, buffer, lenp, ppos); |
| 110 | |
| 111 | if (write && !rc && lenp_bef == *lenp) { |
| 112 | int newval = *((int *)(ipc_table.data)); |
| 113 | /* |
| 114 | * The file "auto_msgmni" has correctly been set. |
| 115 | * React by (un)registering the corresponding tunable, if the |
| 116 | * value has changed. |
| 117 | */ |
| 118 | if (newval != oldval) |
| 119 | ipc_auto_callback(newval); |
| 120 | } |
| 121 | |
| 122 | return rc; |
| 123 | } |
| 124 | |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 125 | #else |
| 126 | #define proc_ipc_doulongvec_minmax NULL |
| 127 | #define proc_ipc_dointvec NULL |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 128 | #define proc_ipc_callback_dointvec NULL |
Nadia Derbey | 9eefe52 | 2008-07-25 01:48:08 -0700 | [diff] [blame] | 129 | #define proc_ipcauto_dointvec_minmax NULL |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 130 | #endif |
| 131 | |
| 132 | #ifdef CONFIG_SYSCTL_SYSCALL |
| 133 | /* The generic sysctl ipc data routine. */ |
Alexey Dobriyan | f221e72 | 2008-10-15 22:04:23 -0700 | [diff] [blame] | 134 | static int sysctl_ipc_data(ctl_table *table, |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 135 | void __user *oldval, size_t __user *oldlenp, |
| 136 | void __user *newval, size_t newlen) |
| 137 | { |
| 138 | size_t len; |
| 139 | void *data; |
| 140 | |
| 141 | /* Get out of I don't have a variable */ |
| 142 | if (!table->data || !table->maxlen) |
| 143 | return -ENOTDIR; |
| 144 | |
| 145 | data = get_ipc(table); |
| 146 | if (!data) |
| 147 | return -ENOTDIR; |
| 148 | |
| 149 | if (oldval && oldlenp) { |
| 150 | if (get_user(len, oldlenp)) |
| 151 | return -EFAULT; |
| 152 | if (len) { |
| 153 | if (len > table->maxlen) |
| 154 | len = table->maxlen; |
| 155 | if (copy_to_user(oldval, data, len)) |
| 156 | return -EFAULT; |
| 157 | if (put_user(len, oldlenp)) |
| 158 | return -EFAULT; |
| 159 | } |
| 160 | } |
| 161 | |
| 162 | if (newval && newlen) { |
| 163 | if (newlen > table->maxlen) |
| 164 | newlen = table->maxlen; |
| 165 | |
| 166 | if (copy_from_user(data, newval, newlen)) |
| 167 | return -EFAULT; |
| 168 | } |
| 169 | return 1; |
| 170 | } |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 171 | |
Alexey Dobriyan | f221e72 | 2008-10-15 22:04:23 -0700 | [diff] [blame] | 172 | static int sysctl_ipc_registered_data(ctl_table *table, |
| 173 | void __user *oldval, size_t __user *oldlenp, |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 174 | void __user *newval, size_t newlen) |
| 175 | { |
| 176 | int rc; |
| 177 | |
Alexey Dobriyan | f221e72 | 2008-10-15 22:04:23 -0700 | [diff] [blame] | 178 | rc = sysctl_ipc_data(table, oldval, oldlenp, newval, newlen); |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 179 | |
Nadia Derbey | 9eefe52 | 2008-07-25 01:48:08 -0700 | [diff] [blame] | 180 | if (newval && newlen && rc > 0) |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 181 | /* |
Nadia Derbey | 6546bc4 | 2008-04-29 01:00:45 -0700 | [diff] [blame] | 182 | * Tunable has successfully been changed from userland |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 183 | */ |
Nadia Derbey | 9eefe52 | 2008-07-25 01:48:08 -0700 | [diff] [blame] | 184 | unregister_ipcns_notifier(current->nsproxy->ipc_ns); |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 185 | |
| 186 | return rc; |
| 187 | } |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 188 | #else |
| 189 | #define sysctl_ipc_data NULL |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 190 | #define sysctl_ipc_registered_data NULL |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 191 | #endif |
| 192 | |
Nadia Derbey | 9eefe52 | 2008-07-25 01:48:08 -0700 | [diff] [blame] | 193 | static int zero; |
| 194 | static int one = 1; |
| 195 | |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 196 | static struct ctl_table ipc_kern_table[] = { |
| 197 | { |
| 198 | .ctl_name = KERN_SHMMAX, |
| 199 | .procname = "shmmax", |
| 200 | .data = &init_ipc_ns.shm_ctlmax, |
| 201 | .maxlen = sizeof (init_ipc_ns.shm_ctlmax), |
| 202 | .mode = 0644, |
| 203 | .proc_handler = proc_ipc_doulongvec_minmax, |
| 204 | .strategy = sysctl_ipc_data, |
| 205 | }, |
| 206 | { |
| 207 | .ctl_name = KERN_SHMALL, |
| 208 | .procname = "shmall", |
| 209 | .data = &init_ipc_ns.shm_ctlall, |
| 210 | .maxlen = sizeof (init_ipc_ns.shm_ctlall), |
| 211 | .mode = 0644, |
| 212 | .proc_handler = proc_ipc_doulongvec_minmax, |
| 213 | .strategy = sysctl_ipc_data, |
| 214 | }, |
| 215 | { |
| 216 | .ctl_name = KERN_SHMMNI, |
| 217 | .procname = "shmmni", |
| 218 | .data = &init_ipc_ns.shm_ctlmni, |
| 219 | .maxlen = sizeof (init_ipc_ns.shm_ctlmni), |
| 220 | .mode = 0644, |
| 221 | .proc_handler = proc_ipc_dointvec, |
| 222 | .strategy = sysctl_ipc_data, |
| 223 | }, |
| 224 | { |
| 225 | .ctl_name = KERN_MSGMAX, |
| 226 | .procname = "msgmax", |
| 227 | .data = &init_ipc_ns.msg_ctlmax, |
| 228 | .maxlen = sizeof (init_ipc_ns.msg_ctlmax), |
| 229 | .mode = 0644, |
| 230 | .proc_handler = proc_ipc_dointvec, |
| 231 | .strategy = sysctl_ipc_data, |
| 232 | }, |
| 233 | { |
| 234 | .ctl_name = KERN_MSGMNI, |
| 235 | .procname = "msgmni", |
| 236 | .data = &init_ipc_ns.msg_ctlmni, |
| 237 | .maxlen = sizeof (init_ipc_ns.msg_ctlmni), |
| 238 | .mode = 0644, |
Nadia Derbey | 91cfb2b | 2008-04-29 01:00:44 -0700 | [diff] [blame] | 239 | .proc_handler = proc_ipc_callback_dointvec, |
| 240 | .strategy = sysctl_ipc_registered_data, |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 241 | }, |
| 242 | { |
| 243 | .ctl_name = KERN_MSGMNB, |
| 244 | .procname = "msgmnb", |
| 245 | .data = &init_ipc_ns.msg_ctlmnb, |
| 246 | .maxlen = sizeof (init_ipc_ns.msg_ctlmnb), |
| 247 | .mode = 0644, |
| 248 | .proc_handler = proc_ipc_dointvec, |
| 249 | .strategy = sysctl_ipc_data, |
| 250 | }, |
| 251 | { |
| 252 | .ctl_name = KERN_SEM, |
| 253 | .procname = "sem", |
| 254 | .data = &init_ipc_ns.sem_ctls, |
| 255 | .maxlen = 4*sizeof (int), |
| 256 | .mode = 0644, |
| 257 | .proc_handler = proc_ipc_dointvec, |
| 258 | .strategy = sysctl_ipc_data, |
| 259 | }, |
Nadia Derbey | 9eefe52 | 2008-07-25 01:48:08 -0700 | [diff] [blame] | 260 | { |
| 261 | .ctl_name = CTL_UNNUMBERED, |
| 262 | .procname = "auto_msgmni", |
| 263 | .data = &init_ipc_ns.auto_msgmni, |
| 264 | .maxlen = sizeof(int), |
| 265 | .mode = 0644, |
| 266 | .proc_handler = proc_ipcauto_dointvec_minmax, |
| 267 | .extra1 = &zero, |
| 268 | .extra2 = &one, |
| 269 | }, |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 270 | {} |
| 271 | }; |
| 272 | |
| 273 | static struct ctl_table ipc_root_table[] = { |
| 274 | { |
| 275 | .ctl_name = CTL_KERN, |
| 276 | .procname = "kernel", |
| 277 | .mode = 0555, |
| 278 | .child = ipc_kern_table, |
| 279 | }, |
| 280 | {} |
| 281 | }; |
| 282 | |
| 283 | static int __init ipc_sysctl_init(void) |
| 284 | { |
Eric W. Biederman | 0b4d414 | 2007-02-14 00:34:09 -0800 | [diff] [blame] | 285 | register_sysctl_table(ipc_root_table); |
Eric W. Biederman | a5494dc | 2007-02-14 00:34:06 -0800 | [diff] [blame] | 286 | return 0; |
| 287 | } |
| 288 | |
| 289 | __initcall(ipc_sysctl_init); |