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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/ipc/shm.c | |
3 | * Copyright (C) 1992, 1993 Krishna Balasubramanian | |
4 | * Many improvements/fixes by Bruno Haible. | |
5 | * Replaced `struct shm_desc' by `struct vm_area_struct', July 1994. | |
6 | * Fixed the shm swap deallocation (shm_unuse()), August 1998 Andrea Arcangeli. | |
7 | * | |
8 | * /proc/sysvipc/shm support (c) 1999 Dragos Acostachioaie <dragos@iname.com> | |
9 | * BIGMEM support, Andrea Arcangeli <andrea@suse.de> | |
10 | * SMP thread shm, Jean-Luc Boyard <jean-luc.boyard@siemens.fr> | |
11 | * HIGHMEM support, Ingo Molnar <mingo@redhat.com> | |
12 | * Make shmmax, shmall, shmmni sysctl'able, Christoph Rohland <cr@sap.com> | |
13 | * Shared /dev/zero support, Kanoj Sarcar <kanoj@sgi.com> | |
14 | * Move the mm functionality over to mm/shmem.c, Christoph Rohland <cr@sap.com> | |
15 | * | |
073115d6 SG |
16 | * support for audit of ipc object properties and permission changes |
17 | * Dustin Kirkland <dustin.kirkland@us.ibm.com> | |
4e982311 KK |
18 | * |
19 | * namespaces support | |
20 | * OpenVZ, SWsoft Inc. | |
21 | * Pavel Emelianov <xemul@openvz.org> | |
1da177e4 LT |
22 | */ |
23 | ||
1da177e4 LT |
24 | #include <linux/slab.h> |
25 | #include <linux/mm.h> | |
26 | #include <linux/hugetlb.h> | |
27 | #include <linux/shm.h> | |
28 | #include <linux/init.h> | |
29 | #include <linux/file.h> | |
30 | #include <linux/mman.h> | |
1da177e4 LT |
31 | #include <linux/shmem_fs.h> |
32 | #include <linux/security.h> | |
33 | #include <linux/syscalls.h> | |
34 | #include <linux/audit.h> | |
c59ede7b | 35 | #include <linux/capability.h> |
7d87e14c | 36 | #include <linux/ptrace.h> |
19b4946c | 37 | #include <linux/seq_file.h> |
3e148c79 | 38 | #include <linux/rwsem.h> |
4e982311 | 39 | #include <linux/nsproxy.h> |
bc56bba8 | 40 | #include <linux/mount.h> |
ae5e1b22 | 41 | #include <linux/ipc_namespace.h> |
7d87e14c | 42 | |
1da177e4 LT |
43 | #include <asm/uaccess.h> |
44 | ||
45 | #include "util.h" | |
46 | ||
bc56bba8 EB |
47 | struct shm_file_data { |
48 | int id; | |
49 | struct ipc_namespace *ns; | |
50 | struct file *file; | |
51 | const struct vm_operations_struct *vm_ops; | |
52 | }; | |
53 | ||
54 | #define shm_file_data(file) (*((struct shm_file_data **)&(file)->private_data)) | |
55 | ||
9a32144e | 56 | static const struct file_operations shm_file_operations; |
1da177e4 LT |
57 | static struct vm_operations_struct shm_vm_ops; |
58 | ||
ed2ddbf8 | 59 | #define shm_ids(ns) ((ns)->ids[IPC_SHM_IDS]) |
1da177e4 | 60 | |
4e982311 KK |
61 | #define shm_unlock(shp) \ |
62 | ipc_unlock(&(shp)->shm_perm) | |
1da177e4 | 63 | |
7748dbfa | 64 | static int newseg(struct ipc_namespace *, struct ipc_params *); |
bc56bba8 EB |
65 | static void shm_open(struct vm_area_struct *vma); |
66 | static void shm_close(struct vm_area_struct *vma); | |
4e982311 | 67 | static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp); |
1da177e4 | 68 | #ifdef CONFIG_PROC_FS |
19b4946c | 69 | static int sysvipc_shm_proc_show(struct seq_file *s, void *it); |
1da177e4 LT |
70 | #endif |
71 | ||
ed2ddbf8 | 72 | void shm_init_ns(struct ipc_namespace *ns) |
4e982311 | 73 | { |
4e982311 KK |
74 | ns->shm_ctlmax = SHMMAX; |
75 | ns->shm_ctlall = SHMALL; | |
76 | ns->shm_ctlmni = SHMMNI; | |
77 | ns->shm_tot = 0; | |
e8148f75 | 78 | ipc_init_ids(&shm_ids(ns)); |
4e982311 KK |
79 | } |
80 | ||
f4566f04 | 81 | /* |
3e148c79 ND |
82 | * Called with shm_ids.rw_mutex (writer) and the shp structure locked. |
83 | * Only shm_ids.rw_mutex remains locked on exit. | |
f4566f04 | 84 | */ |
01b8b07a | 85 | static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) |
4e982311 | 86 | { |
01b8b07a PP |
87 | struct shmid_kernel *shp; |
88 | shp = container_of(ipcp, struct shmid_kernel, shm_perm); | |
89 | ||
4e982311 KK |
90 | if (shp->shm_nattch){ |
91 | shp->shm_perm.mode |= SHM_DEST; | |
92 | /* Do not find it any more */ | |
93 | shp->shm_perm.key = IPC_PRIVATE; | |
94 | shm_unlock(shp); | |
95 | } else | |
96 | shm_destroy(ns, shp); | |
97 | } | |
98 | ||
ae5e1b22 | 99 | #ifdef CONFIG_IPC_NS |
4e982311 KK |
100 | void shm_exit_ns(struct ipc_namespace *ns) |
101 | { | |
01b8b07a | 102 | free_ipcs(ns, &shm_ids(ns), do_shm_rmid); |
4e982311 | 103 | } |
ae5e1b22 | 104 | #endif |
1da177e4 LT |
105 | |
106 | void __init shm_init (void) | |
107 | { | |
ed2ddbf8 | 108 | shm_init_ns(&init_ipc_ns); |
19b4946c MW |
109 | ipc_init_proc_interface("sysvipc/shm", |
110 | " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime\n", | |
4e982311 | 111 | IPC_SHM_IDS, sysvipc_shm_proc_show); |
1da177e4 LT |
112 | } |
113 | ||
3e148c79 ND |
114 | /* |
115 | * shm_lock_(check_) routines are called in the paths where the rw_mutex | |
00c2bf85 | 116 | * is not necessarily held. |
3e148c79 | 117 | */ |
023a5355 | 118 | static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id) |
1da177e4 | 119 | { |
03f02c76 ND |
120 | struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id); |
121 | ||
b1ed88b4 PP |
122 | if (IS_ERR(ipcp)) |
123 | return (struct shmid_kernel *)ipcp; | |
124 | ||
03f02c76 | 125 | return container_of(ipcp, struct shmid_kernel, shm_perm); |
023a5355 ND |
126 | } |
127 | ||
128 | static inline struct shmid_kernel *shm_lock_check(struct ipc_namespace *ns, | |
129 | int id) | |
130 | { | |
03f02c76 ND |
131 | struct kern_ipc_perm *ipcp = ipc_lock_check(&shm_ids(ns), id); |
132 | ||
b1ed88b4 PP |
133 | if (IS_ERR(ipcp)) |
134 | return (struct shmid_kernel *)ipcp; | |
135 | ||
03f02c76 | 136 | return container_of(ipcp, struct shmid_kernel, shm_perm); |
1da177e4 LT |
137 | } |
138 | ||
7ca7e564 | 139 | static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s) |
1da177e4 | 140 | { |
7ca7e564 | 141 | ipc_rmid(&shm_ids(ns), &s->shm_perm); |
1da177e4 LT |
142 | } |
143 | ||
1da177e4 | 144 | |
bc56bba8 EB |
145 | /* This is called by fork, once for every shm attach. */ |
146 | static void shm_open(struct vm_area_struct *vma) | |
4e982311 | 147 | { |
bc56bba8 EB |
148 | struct file *file = vma->vm_file; |
149 | struct shm_file_data *sfd = shm_file_data(file); | |
1da177e4 LT |
150 | struct shmid_kernel *shp; |
151 | ||
bc56bba8 | 152 | shp = shm_lock(sfd->ns, sfd->id); |
023a5355 | 153 | BUG_ON(IS_ERR(shp)); |
1da177e4 | 154 | shp->shm_atim = get_seconds(); |
b488893a | 155 | shp->shm_lprid = task_tgid_vnr(current); |
1da177e4 LT |
156 | shp->shm_nattch++; |
157 | shm_unlock(shp); | |
158 | } | |
159 | ||
1da177e4 LT |
160 | /* |
161 | * shm_destroy - free the struct shmid_kernel | |
162 | * | |
f4566f04 | 163 | * @ns: namespace |
1da177e4 LT |
164 | * @shp: struct to free |
165 | * | |
3e148c79 | 166 | * It has to be called with shp and shm_ids.rw_mutex (writer) locked, |
1da177e4 LT |
167 | * but returns with shp unlocked and freed. |
168 | */ | |
4e982311 | 169 | static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp) |
1da177e4 | 170 | { |
4e982311 | 171 | ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT; |
7ca7e564 | 172 | shm_rmid(ns, shp); |
1da177e4 LT |
173 | shm_unlock(shp); |
174 | if (!is_file_hugepages(shp->shm_file)) | |
175 | shmem_lock(shp->shm_file, 0, shp->mlock_user); | |
176 | else | |
6d63079a | 177 | user_shm_unlock(shp->shm_file->f_path.dentry->d_inode->i_size, |
1da177e4 LT |
178 | shp->mlock_user); |
179 | fput (shp->shm_file); | |
180 | security_shm_free(shp); | |
181 | ipc_rcu_putref(shp); | |
182 | } | |
183 | ||
184 | /* | |
bc56bba8 | 185 | * remove the attach descriptor vma. |
1da177e4 LT |
186 | * free memory for segment if it is marked destroyed. |
187 | * The descriptor has already been removed from the current->mm->mmap list | |
188 | * and will later be kfree()d. | |
189 | */ | |
bc56bba8 | 190 | static void shm_close(struct vm_area_struct *vma) |
1da177e4 | 191 | { |
bc56bba8 EB |
192 | struct file * file = vma->vm_file; |
193 | struct shm_file_data *sfd = shm_file_data(file); | |
1da177e4 | 194 | struct shmid_kernel *shp; |
bc56bba8 | 195 | struct ipc_namespace *ns = sfd->ns; |
4e982311 | 196 | |
3e148c79 | 197 | down_write(&shm_ids(ns).rw_mutex); |
1da177e4 | 198 | /* remove from the list of attaches of the shm segment */ |
00c2bf85 | 199 | shp = shm_lock(ns, sfd->id); |
023a5355 | 200 | BUG_ON(IS_ERR(shp)); |
b488893a | 201 | shp->shm_lprid = task_tgid_vnr(current); |
1da177e4 LT |
202 | shp->shm_dtim = get_seconds(); |
203 | shp->shm_nattch--; | |
204 | if(shp->shm_nattch == 0 && | |
b33291c0 | 205 | shp->shm_perm.mode & SHM_DEST) |
4e982311 | 206 | shm_destroy(ns, shp); |
1da177e4 LT |
207 | else |
208 | shm_unlock(shp); | |
3e148c79 | 209 | up_write(&shm_ids(ns).rw_mutex); |
1da177e4 LT |
210 | } |
211 | ||
d0217ac0 | 212 | static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
bc56bba8 EB |
213 | { |
214 | struct file *file = vma->vm_file; | |
215 | struct shm_file_data *sfd = shm_file_data(file); | |
216 | ||
d0217ac0 | 217 | return sfd->vm_ops->fault(vma, vmf); |
bc56bba8 EB |
218 | } |
219 | ||
220 | #ifdef CONFIG_NUMA | |
d823e3e7 | 221 | static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new) |
bc56bba8 EB |
222 | { |
223 | struct file *file = vma->vm_file; | |
224 | struct shm_file_data *sfd = shm_file_data(file); | |
225 | int err = 0; | |
226 | if (sfd->vm_ops->set_policy) | |
227 | err = sfd->vm_ops->set_policy(vma, new); | |
228 | return err; | |
229 | } | |
230 | ||
d823e3e7 AB |
231 | static struct mempolicy *shm_get_policy(struct vm_area_struct *vma, |
232 | unsigned long addr) | |
bc56bba8 EB |
233 | { |
234 | struct file *file = vma->vm_file; | |
235 | struct shm_file_data *sfd = shm_file_data(file); | |
236 | struct mempolicy *pol = NULL; | |
237 | ||
238 | if (sfd->vm_ops->get_policy) | |
239 | pol = sfd->vm_ops->get_policy(vma, addr); | |
52cd3b07 | 240 | else if (vma->vm_policy) |
bc56bba8 | 241 | pol = vma->vm_policy; |
52cd3b07 | 242 | |
bc56bba8 EB |
243 | return pol; |
244 | } | |
245 | #endif | |
246 | ||
1da177e4 LT |
247 | static int shm_mmap(struct file * file, struct vm_area_struct * vma) |
248 | { | |
bc56bba8 | 249 | struct shm_file_data *sfd = shm_file_data(file); |
b0e15190 DH |
250 | int ret; |
251 | ||
bc56bba8 EB |
252 | ret = sfd->file->f_op->mmap(sfd->file, vma); |
253 | if (ret != 0) | |
254 | return ret; | |
255 | sfd->vm_ops = vma->vm_ops; | |
2e92a3ba | 256 | #ifdef CONFIG_MMU |
54cb8821 | 257 | BUG_ON(!sfd->vm_ops->fault); |
2e92a3ba | 258 | #endif |
bc56bba8 EB |
259 | vma->vm_ops = &shm_vm_ops; |
260 | shm_open(vma); | |
b0e15190 DH |
261 | |
262 | return ret; | |
1da177e4 LT |
263 | } |
264 | ||
4e982311 KK |
265 | static int shm_release(struct inode *ino, struct file *file) |
266 | { | |
bc56bba8 | 267 | struct shm_file_data *sfd = shm_file_data(file); |
4e982311 | 268 | |
bc56bba8 EB |
269 | put_ipc_ns(sfd->ns); |
270 | shm_file_data(file) = NULL; | |
271 | kfree(sfd); | |
4e982311 KK |
272 | return 0; |
273 | } | |
274 | ||
516dffdc AL |
275 | static int shm_fsync(struct file *file, struct dentry *dentry, int datasync) |
276 | { | |
277 | int (*fsync) (struct file *, struct dentry *, int datasync); | |
278 | struct shm_file_data *sfd = shm_file_data(file); | |
279 | int ret = -EINVAL; | |
280 | ||
281 | fsync = sfd->file->f_op->fsync; | |
282 | if (fsync) | |
283 | ret = fsync(sfd->file, sfd->file->f_path.dentry, datasync); | |
284 | return ret; | |
285 | } | |
286 | ||
bc56bba8 EB |
287 | static unsigned long shm_get_unmapped_area(struct file *file, |
288 | unsigned long addr, unsigned long len, unsigned long pgoff, | |
289 | unsigned long flags) | |
290 | { | |
291 | struct shm_file_data *sfd = shm_file_data(file); | |
516dffdc AL |
292 | return get_unmapped_area(sfd->file, addr, len, pgoff, flags); |
293 | } | |
294 | ||
295 | int is_file_shm_hugepages(struct file *file) | |
296 | { | |
297 | int ret = 0; | |
298 | ||
299 | if (file->f_op == &shm_file_operations) { | |
300 | struct shm_file_data *sfd; | |
301 | sfd = shm_file_data(file); | |
302 | ret = is_file_hugepages(sfd->file); | |
303 | } | |
304 | return ret; | |
bc56bba8 | 305 | } |
bc56bba8 | 306 | |
9a32144e | 307 | static const struct file_operations shm_file_operations = { |
4e982311 | 308 | .mmap = shm_mmap, |
516dffdc | 309 | .fsync = shm_fsync, |
4e982311 | 310 | .release = shm_release, |
bc56bba8 | 311 | .get_unmapped_area = shm_get_unmapped_area, |
1da177e4 LT |
312 | }; |
313 | ||
314 | static struct vm_operations_struct shm_vm_ops = { | |
315 | .open = shm_open, /* callback for a new vm-area open */ | |
316 | .close = shm_close, /* callback for when the vm-area is released */ | |
54cb8821 | 317 | .fault = shm_fault, |
bc56bba8 EB |
318 | #if defined(CONFIG_NUMA) |
319 | .set_policy = shm_set_policy, | |
320 | .get_policy = shm_get_policy, | |
1da177e4 LT |
321 | #endif |
322 | }; | |
323 | ||
f4566f04 ND |
324 | /** |
325 | * newseg - Create a new shared memory segment | |
326 | * @ns: namespace | |
327 | * @params: ptr to the structure that contains key, size and shmflg | |
328 | * | |
3e148c79 | 329 | * Called with shm_ids.rw_mutex held as a writer. |
f4566f04 ND |
330 | */ |
331 | ||
7748dbfa | 332 | static int newseg(struct ipc_namespace *ns, struct ipc_params *params) |
1da177e4 | 333 | { |
7748dbfa ND |
334 | key_t key = params->key; |
335 | int shmflg = params->flg; | |
336 | size_t size = params->u.size; | |
1da177e4 LT |
337 | int error; |
338 | struct shmid_kernel *shp; | |
339 | int numpages = (size + PAGE_SIZE -1) >> PAGE_SHIFT; | |
340 | struct file * file; | |
341 | char name[13]; | |
342 | int id; | |
343 | ||
4e982311 | 344 | if (size < SHMMIN || size > ns->shm_ctlmax) |
1da177e4 LT |
345 | return -EINVAL; |
346 | ||
f66d45e9 | 347 | if (ns->shm_tot + numpages > ns->shm_ctlall) |
1da177e4 LT |
348 | return -ENOSPC; |
349 | ||
350 | shp = ipc_rcu_alloc(sizeof(*shp)); | |
351 | if (!shp) | |
352 | return -ENOMEM; | |
353 | ||
354 | shp->shm_perm.key = key; | |
b33291c0 | 355 | shp->shm_perm.mode = (shmflg & S_IRWXUGO); |
1da177e4 LT |
356 | shp->mlock_user = NULL; |
357 | ||
358 | shp->shm_perm.security = NULL; | |
359 | error = security_shm_alloc(shp); | |
360 | if (error) { | |
361 | ipc_rcu_putref(shp); | |
362 | return error; | |
363 | } | |
364 | ||
9d66586f | 365 | sprintf (name, "SYSV%08x", key); |
1da177e4 | 366 | if (shmflg & SHM_HUGETLB) { |
9d66586f EB |
367 | /* hugetlb_file_setup takes care of mlock user accounting */ |
368 | file = hugetlb_file_setup(name, size); | |
86a264ab | 369 | shp->mlock_user = current_user(); |
1da177e4 | 370 | } else { |
fc8744ad | 371 | int acctflag = 0; |
bf8f972d BP |
372 | /* |
373 | * Do not allow no accounting for OVERCOMMIT_NEVER, even | |
374 | * if it's asked for. | |
375 | */ | |
376 | if ((shmflg & SHM_NORESERVE) && | |
377 | sysctl_overcommit_memory != OVERCOMMIT_NEVER) | |
fc8744ad | 378 | acctflag = VM_NORESERVE; |
bf8f972d | 379 | file = shmem_file_setup(name, size, acctflag); |
1da177e4 LT |
380 | } |
381 | error = PTR_ERR(file); | |
382 | if (IS_ERR(file)) | |
383 | goto no_file; | |
384 | ||
48dea404 | 385 | id = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni); |
283bb7fa PP |
386 | if (id < 0) { |
387 | error = id; | |
1da177e4 | 388 | goto no_id; |
283bb7fa | 389 | } |
1da177e4 | 390 | |
b488893a | 391 | shp->shm_cprid = task_tgid_vnr(current); |
1da177e4 LT |
392 | shp->shm_lprid = 0; |
393 | shp->shm_atim = shp->shm_dtim = 0; | |
394 | shp->shm_ctim = get_seconds(); | |
395 | shp->shm_segsz = size; | |
396 | shp->shm_nattch = 0; | |
1da177e4 | 397 | shp->shm_file = file; |
30475cc1 BP |
398 | /* |
399 | * shmid gets reported as "inode#" in /proc/pid/maps. | |
400 | * proc-ps tools use this. Changing this will break them. | |
401 | */ | |
7ca7e564 | 402 | file->f_dentry->d_inode->i_ino = shp->shm_perm.id; |
551110a9 | 403 | |
4e982311 | 404 | ns->shm_tot += numpages; |
7ca7e564 | 405 | error = shp->shm_perm.id; |
1da177e4 | 406 | shm_unlock(shp); |
7ca7e564 | 407 | return error; |
1da177e4 LT |
408 | |
409 | no_id: | |
410 | fput(file); | |
411 | no_file: | |
412 | security_shm_free(shp); | |
413 | ipc_rcu_putref(shp); | |
414 | return error; | |
415 | } | |
416 | ||
f4566f04 | 417 | /* |
3e148c79 | 418 | * Called with shm_ids.rw_mutex and ipcp locked. |
f4566f04 | 419 | */ |
03f02c76 | 420 | static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg) |
7748dbfa | 421 | { |
03f02c76 ND |
422 | struct shmid_kernel *shp; |
423 | ||
424 | shp = container_of(ipcp, struct shmid_kernel, shm_perm); | |
425 | return security_shm_associate(shp, shmflg); | |
7748dbfa ND |
426 | } |
427 | ||
f4566f04 | 428 | /* |
3e148c79 | 429 | * Called with shm_ids.rw_mutex and ipcp locked. |
f4566f04 | 430 | */ |
03f02c76 ND |
431 | static inline int shm_more_checks(struct kern_ipc_perm *ipcp, |
432 | struct ipc_params *params) | |
7748dbfa | 433 | { |
03f02c76 ND |
434 | struct shmid_kernel *shp; |
435 | ||
436 | shp = container_of(ipcp, struct shmid_kernel, shm_perm); | |
437 | if (shp->shm_segsz < params->u.size) | |
7748dbfa ND |
438 | return -EINVAL; |
439 | ||
440 | return 0; | |
441 | } | |
442 | ||
d5460c99 | 443 | SYSCALL_DEFINE3(shmget, key_t, key, size_t, size, int, shmflg) |
1da177e4 | 444 | { |
4e982311 | 445 | struct ipc_namespace *ns; |
7748dbfa ND |
446 | struct ipc_ops shm_ops; |
447 | struct ipc_params shm_params; | |
4e982311 KK |
448 | |
449 | ns = current->nsproxy->ipc_ns; | |
1da177e4 | 450 | |
7748dbfa ND |
451 | shm_ops.getnew = newseg; |
452 | shm_ops.associate = shm_security; | |
453 | shm_ops.more_checks = shm_more_checks; | |
7ca7e564 | 454 | |
7748dbfa ND |
455 | shm_params.key = key; |
456 | shm_params.flg = shmflg; | |
457 | shm_params.u.size = size; | |
1da177e4 | 458 | |
7748dbfa | 459 | return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params); |
1da177e4 LT |
460 | } |
461 | ||
462 | static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version) | |
463 | { | |
464 | switch(version) { | |
465 | case IPC_64: | |
466 | return copy_to_user(buf, in, sizeof(*in)); | |
467 | case IPC_OLD: | |
468 | { | |
469 | struct shmid_ds out; | |
470 | ||
471 | ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm); | |
472 | out.shm_segsz = in->shm_segsz; | |
473 | out.shm_atime = in->shm_atime; | |
474 | out.shm_dtime = in->shm_dtime; | |
475 | out.shm_ctime = in->shm_ctime; | |
476 | out.shm_cpid = in->shm_cpid; | |
477 | out.shm_lpid = in->shm_lpid; | |
478 | out.shm_nattch = in->shm_nattch; | |
479 | ||
480 | return copy_to_user(buf, &out, sizeof(out)); | |
481 | } | |
482 | default: | |
483 | return -EINVAL; | |
484 | } | |
485 | } | |
486 | ||
016d7132 PP |
487 | static inline unsigned long |
488 | copy_shmid_from_user(struct shmid64_ds *out, void __user *buf, int version) | |
1da177e4 LT |
489 | { |
490 | switch(version) { | |
491 | case IPC_64: | |
016d7132 | 492 | if (copy_from_user(out, buf, sizeof(*out))) |
1da177e4 | 493 | return -EFAULT; |
1da177e4 | 494 | return 0; |
1da177e4 LT |
495 | case IPC_OLD: |
496 | { | |
497 | struct shmid_ds tbuf_old; | |
498 | ||
499 | if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) | |
500 | return -EFAULT; | |
501 | ||
016d7132 PP |
502 | out->shm_perm.uid = tbuf_old.shm_perm.uid; |
503 | out->shm_perm.gid = tbuf_old.shm_perm.gid; | |
504 | out->shm_perm.mode = tbuf_old.shm_perm.mode; | |
1da177e4 LT |
505 | |
506 | return 0; | |
507 | } | |
508 | default: | |
509 | return -EINVAL; | |
510 | } | |
511 | } | |
512 | ||
513 | static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminfo64 *in, int version) | |
514 | { | |
515 | switch(version) { | |
516 | case IPC_64: | |
517 | return copy_to_user(buf, in, sizeof(*in)); | |
518 | case IPC_OLD: | |
519 | { | |
520 | struct shminfo out; | |
521 | ||
522 | if(in->shmmax > INT_MAX) | |
523 | out.shmmax = INT_MAX; | |
524 | else | |
525 | out.shmmax = (int)in->shmmax; | |
526 | ||
527 | out.shmmin = in->shmmin; | |
528 | out.shmmni = in->shmmni; | |
529 | out.shmseg = in->shmseg; | |
530 | out.shmall = in->shmall; | |
531 | ||
532 | return copy_to_user(buf, &out, sizeof(out)); | |
533 | } | |
534 | default: | |
535 | return -EINVAL; | |
536 | } | |
537 | } | |
538 | ||
f4566f04 | 539 | /* |
3e148c79 | 540 | * Called with shm_ids.rw_mutex held as a reader |
f4566f04 | 541 | */ |
4e982311 KK |
542 | static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss, |
543 | unsigned long *swp) | |
1da177e4 | 544 | { |
7ca7e564 ND |
545 | int next_id; |
546 | int total, in_use; | |
1da177e4 LT |
547 | |
548 | *rss = 0; | |
549 | *swp = 0; | |
550 | ||
7ca7e564 ND |
551 | in_use = shm_ids(ns).in_use; |
552 | ||
553 | for (total = 0, next_id = 0; total < in_use; next_id++) { | |
1da177e4 LT |
554 | struct shmid_kernel *shp; |
555 | struct inode *inode; | |
556 | ||
637c3663 | 557 | shp = idr_find(&shm_ids(ns).ipcs_idr, next_id); |
7ca7e564 | 558 | if (shp == NULL) |
1da177e4 LT |
559 | continue; |
560 | ||
6d63079a | 561 | inode = shp->shm_file->f_path.dentry->d_inode; |
1da177e4 LT |
562 | |
563 | if (is_file_hugepages(shp->shm_file)) { | |
564 | struct address_space *mapping = inode->i_mapping; | |
a5516438 AK |
565 | struct hstate *h = hstate_file(shp->shm_file); |
566 | *rss += pages_per_huge_page(h) * mapping->nrpages; | |
1da177e4 | 567 | } else { |
a68e61e8 | 568 | #ifdef CONFIG_SHMEM |
1da177e4 LT |
569 | struct shmem_inode_info *info = SHMEM_I(inode); |
570 | spin_lock(&info->lock); | |
571 | *rss += inode->i_mapping->nrpages; | |
572 | *swp += info->swapped; | |
573 | spin_unlock(&info->lock); | |
a68e61e8 TB |
574 | #else |
575 | *rss += inode->i_mapping->nrpages; | |
576 | #endif | |
1da177e4 | 577 | } |
7ca7e564 ND |
578 | |
579 | total++; | |
1da177e4 LT |
580 | } |
581 | } | |
582 | ||
8d4cc8b5 PP |
583 | /* |
584 | * This function handles some shmctl commands which require the rw_mutex | |
585 | * to be held in write mode. | |
586 | * NOTE: no locks must be held, the rw_mutex is taken inside this function. | |
587 | */ | |
588 | static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd, | |
589 | struct shmid_ds __user *buf, int version) | |
1da177e4 | 590 | { |
8d4cc8b5 | 591 | struct kern_ipc_perm *ipcp; |
016d7132 | 592 | struct shmid64_ds shmid64; |
8d4cc8b5 PP |
593 | struct shmid_kernel *shp; |
594 | int err; | |
595 | ||
596 | if (cmd == IPC_SET) { | |
016d7132 | 597 | if (copy_shmid_from_user(&shmid64, buf, version)) |
8d4cc8b5 PP |
598 | return -EFAULT; |
599 | } | |
600 | ||
a5f75e7f PP |
601 | ipcp = ipcctl_pre_down(&shm_ids(ns), shmid, cmd, &shmid64.shm_perm, 0); |
602 | if (IS_ERR(ipcp)) | |
603 | return PTR_ERR(ipcp); | |
8d4cc8b5 | 604 | |
a5f75e7f | 605 | shp = container_of(ipcp, struct shmid_kernel, shm_perm); |
8d4cc8b5 PP |
606 | |
607 | err = security_shm_shmctl(shp, cmd); | |
608 | if (err) | |
609 | goto out_unlock; | |
610 | switch (cmd) { | |
611 | case IPC_RMID: | |
612 | do_shm_rmid(ns, ipcp); | |
613 | goto out_up; | |
614 | case IPC_SET: | |
8f4a3809 | 615 | ipc_update_perm(&shmid64.shm_perm, ipcp); |
8d4cc8b5 PP |
616 | shp->shm_ctim = get_seconds(); |
617 | break; | |
618 | default: | |
619 | err = -EINVAL; | |
620 | } | |
621 | out_unlock: | |
622 | shm_unlock(shp); | |
623 | out_up: | |
624 | up_write(&shm_ids(ns).rw_mutex); | |
625 | return err; | |
626 | } | |
627 | ||
d5460c99 | 628 | SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf) |
8d4cc8b5 | 629 | { |
1da177e4 LT |
630 | struct shmid_kernel *shp; |
631 | int err, version; | |
4e982311 | 632 | struct ipc_namespace *ns; |
1da177e4 LT |
633 | |
634 | if (cmd < 0 || shmid < 0) { | |
635 | err = -EINVAL; | |
636 | goto out; | |
637 | } | |
638 | ||
639 | version = ipc_parse_version(&cmd); | |
4e982311 | 640 | ns = current->nsproxy->ipc_ns; |
1da177e4 LT |
641 | |
642 | switch (cmd) { /* replace with proc interface ? */ | |
643 | case IPC_INFO: | |
644 | { | |
645 | struct shminfo64 shminfo; | |
646 | ||
647 | err = security_shm_shmctl(NULL, cmd); | |
648 | if (err) | |
649 | return err; | |
650 | ||
e8148f75 | 651 | memset(&shminfo, 0, sizeof(shminfo)); |
4e982311 KK |
652 | shminfo.shmmni = shminfo.shmseg = ns->shm_ctlmni; |
653 | shminfo.shmmax = ns->shm_ctlmax; | |
654 | shminfo.shmall = ns->shm_ctlall; | |
1da177e4 LT |
655 | |
656 | shminfo.shmmin = SHMMIN; | |
657 | if(copy_shminfo_to_user (buf, &shminfo, version)) | |
658 | return -EFAULT; | |
f4566f04 | 659 | |
3e148c79 | 660 | down_read(&shm_ids(ns).rw_mutex); |
7ca7e564 | 661 | err = ipc_get_maxid(&shm_ids(ns)); |
3e148c79 | 662 | up_read(&shm_ids(ns).rw_mutex); |
f4566f04 | 663 | |
1da177e4 LT |
664 | if(err<0) |
665 | err = 0; | |
666 | goto out; | |
667 | } | |
668 | case SHM_INFO: | |
669 | { | |
670 | struct shm_info shm_info; | |
671 | ||
672 | err = security_shm_shmctl(NULL, cmd); | |
673 | if (err) | |
674 | return err; | |
675 | ||
e8148f75 | 676 | memset(&shm_info, 0, sizeof(shm_info)); |
3e148c79 | 677 | down_read(&shm_ids(ns).rw_mutex); |
4e982311 KK |
678 | shm_info.used_ids = shm_ids(ns).in_use; |
679 | shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp); | |
680 | shm_info.shm_tot = ns->shm_tot; | |
1da177e4 LT |
681 | shm_info.swap_attempts = 0; |
682 | shm_info.swap_successes = 0; | |
7ca7e564 | 683 | err = ipc_get_maxid(&shm_ids(ns)); |
3e148c79 | 684 | up_read(&shm_ids(ns).rw_mutex); |
e8148f75 | 685 | if (copy_to_user(buf, &shm_info, sizeof(shm_info))) { |
1da177e4 LT |
686 | err = -EFAULT; |
687 | goto out; | |
688 | } | |
689 | ||
690 | err = err < 0 ? 0 : err; | |
691 | goto out; | |
692 | } | |
693 | case SHM_STAT: | |
694 | case IPC_STAT: | |
695 | { | |
696 | struct shmid64_ds tbuf; | |
697 | int result; | |
023a5355 | 698 | |
023a5355 ND |
699 | if (cmd == SHM_STAT) { |
700 | shp = shm_lock(ns, shmid); | |
701 | if (IS_ERR(shp)) { | |
702 | err = PTR_ERR(shp); | |
703 | goto out; | |
704 | } | |
7ca7e564 | 705 | result = shp->shm_perm.id; |
1da177e4 | 706 | } else { |
023a5355 ND |
707 | shp = shm_lock_check(ns, shmid); |
708 | if (IS_ERR(shp)) { | |
709 | err = PTR_ERR(shp); | |
710 | goto out; | |
711 | } | |
1da177e4 LT |
712 | result = 0; |
713 | } | |
e8148f75 | 714 | err = -EACCES; |
1da177e4 LT |
715 | if (ipcperms (&shp->shm_perm, S_IRUGO)) |
716 | goto out_unlock; | |
717 | err = security_shm_shmctl(shp, cmd); | |
718 | if (err) | |
719 | goto out_unlock; | |
023a5355 | 720 | memset(&tbuf, 0, sizeof(tbuf)); |
1da177e4 LT |
721 | kernel_to_ipc64_perm(&shp->shm_perm, &tbuf.shm_perm); |
722 | tbuf.shm_segsz = shp->shm_segsz; | |
723 | tbuf.shm_atime = shp->shm_atim; | |
724 | tbuf.shm_dtime = shp->shm_dtim; | |
725 | tbuf.shm_ctime = shp->shm_ctim; | |
726 | tbuf.shm_cpid = shp->shm_cprid; | |
727 | tbuf.shm_lpid = shp->shm_lprid; | |
bc56bba8 | 728 | tbuf.shm_nattch = shp->shm_nattch; |
1da177e4 LT |
729 | shm_unlock(shp); |
730 | if(copy_shmid_to_user (buf, &tbuf, version)) | |
731 | err = -EFAULT; | |
732 | else | |
733 | err = result; | |
734 | goto out; | |
735 | } | |
736 | case SHM_LOCK: | |
737 | case SHM_UNLOCK: | |
738 | { | |
89e004ea LS |
739 | struct file *uninitialized_var(shm_file); |
740 | ||
741 | lru_add_drain_all(); /* drain pagevecs to lru lists */ | |
742 | ||
023a5355 ND |
743 | shp = shm_lock_check(ns, shmid); |
744 | if (IS_ERR(shp)) { | |
745 | err = PTR_ERR(shp); | |
1da177e4 LT |
746 | goto out; |
747 | } | |
1da177e4 | 748 | |
a33e6751 | 749 | audit_ipc_obj(&(shp->shm_perm)); |
073115d6 | 750 | |
1da177e4 | 751 | if (!capable(CAP_IPC_LOCK)) { |
414c0708 | 752 | uid_t euid = current_euid(); |
1da177e4 | 753 | err = -EPERM; |
414c0708 DH |
754 | if (euid != shp->shm_perm.uid && |
755 | euid != shp->shm_perm.cuid) | |
1da177e4 LT |
756 | goto out_unlock; |
757 | if (cmd == SHM_LOCK && | |
758 | !current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur) | |
759 | goto out_unlock; | |
760 | } | |
761 | ||
762 | err = security_shm_shmctl(shp, cmd); | |
763 | if (err) | |
764 | goto out_unlock; | |
765 | ||
766 | if(cmd==SHM_LOCK) { | |
86a264ab | 767 | struct user_struct *user = current_user(); |
1da177e4 LT |
768 | if (!is_file_hugepages(shp->shm_file)) { |
769 | err = shmem_lock(shp->shm_file, 1, user); | |
7be77e20 | 770 | if (!err && !(shp->shm_perm.mode & SHM_LOCKED)){ |
b33291c0 | 771 | shp->shm_perm.mode |= SHM_LOCKED; |
1da177e4 LT |
772 | shp->mlock_user = user; |
773 | } | |
774 | } | |
775 | } else if (!is_file_hugepages(shp->shm_file)) { | |
776 | shmem_lock(shp->shm_file, 0, shp->mlock_user); | |
b33291c0 | 777 | shp->shm_perm.mode &= ~SHM_LOCKED; |
1da177e4 LT |
778 | shp->mlock_user = NULL; |
779 | } | |
780 | shm_unlock(shp); | |
781 | goto out; | |
782 | } | |
783 | case IPC_RMID: | |
1da177e4 | 784 | case IPC_SET: |
8d4cc8b5 PP |
785 | err = shmctl_down(ns, shmid, cmd, buf, version); |
786 | return err; | |
1da177e4 | 787 | default: |
8d4cc8b5 | 788 | return -EINVAL; |
1da177e4 LT |
789 | } |
790 | ||
1da177e4 LT |
791 | out_unlock: |
792 | shm_unlock(shp); | |
793 | out: | |
794 | return err; | |
795 | } | |
796 | ||
797 | /* | |
798 | * Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists. | |
799 | * | |
800 | * NOTE! Despite the name, this is NOT a direct system call entrypoint. The | |
801 | * "raddr" thing points to kernel space, and there has to be a wrapper around | |
802 | * this. | |
803 | */ | |
804 | long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr) | |
805 | { | |
806 | struct shmid_kernel *shp; | |
807 | unsigned long addr; | |
808 | unsigned long size; | |
809 | struct file * file; | |
810 | int err; | |
811 | unsigned long flags; | |
812 | unsigned long prot; | |
1da177e4 | 813 | int acc_mode; |
bc56bba8 | 814 | unsigned long user_addr; |
4e982311 | 815 | struct ipc_namespace *ns; |
bc56bba8 EB |
816 | struct shm_file_data *sfd; |
817 | struct path path; | |
aeb5d727 | 818 | fmode_t f_mode; |
1da177e4 | 819 | |
bc56bba8 EB |
820 | err = -EINVAL; |
821 | if (shmid < 0) | |
1da177e4 | 822 | goto out; |
bc56bba8 | 823 | else if ((addr = (ulong)shmaddr)) { |
1da177e4 LT |
824 | if (addr & (SHMLBA-1)) { |
825 | if (shmflg & SHM_RND) | |
826 | addr &= ~(SHMLBA-1); /* round down */ | |
827 | else | |
828 | #ifndef __ARCH_FORCE_SHMLBA | |
829 | if (addr & ~PAGE_MASK) | |
830 | #endif | |
bc56bba8 | 831 | goto out; |
1da177e4 LT |
832 | } |
833 | flags = MAP_SHARED | MAP_FIXED; | |
834 | } else { | |
835 | if ((shmflg & SHM_REMAP)) | |
bc56bba8 | 836 | goto out; |
1da177e4 LT |
837 | |
838 | flags = MAP_SHARED; | |
839 | } | |
840 | ||
841 | if (shmflg & SHM_RDONLY) { | |
842 | prot = PROT_READ; | |
1da177e4 | 843 | acc_mode = S_IRUGO; |
bc56bba8 | 844 | f_mode = FMODE_READ; |
1da177e4 LT |
845 | } else { |
846 | prot = PROT_READ | PROT_WRITE; | |
1da177e4 | 847 | acc_mode = S_IRUGO | S_IWUGO; |
bc56bba8 | 848 | f_mode = FMODE_READ | FMODE_WRITE; |
1da177e4 LT |
849 | } |
850 | if (shmflg & SHM_EXEC) { | |
851 | prot |= PROT_EXEC; | |
852 | acc_mode |= S_IXUGO; | |
853 | } | |
854 | ||
855 | /* | |
856 | * We cannot rely on the fs check since SYSV IPC does have an | |
857 | * additional creator id... | |
858 | */ | |
4e982311 | 859 | ns = current->nsproxy->ipc_ns; |
023a5355 ND |
860 | shp = shm_lock_check(ns, shmid); |
861 | if (IS_ERR(shp)) { | |
862 | err = PTR_ERR(shp); | |
1da177e4 | 863 | goto out; |
023a5355 | 864 | } |
bc56bba8 EB |
865 | |
866 | err = -EACCES; | |
867 | if (ipcperms(&shp->shm_perm, acc_mode)) | |
868 | goto out_unlock; | |
1da177e4 LT |
869 | |
870 | err = security_shm_shmat(shp, shmaddr, shmflg); | |
bc56bba8 EB |
871 | if (err) |
872 | goto out_unlock; | |
873 | ||
874 | path.dentry = dget(shp->shm_file->f_path.dentry); | |
ce8d2cdf | 875 | path.mnt = shp->shm_file->f_path.mnt; |
1da177e4 | 876 | shp->shm_nattch++; |
bc56bba8 | 877 | size = i_size_read(path.dentry->d_inode); |
1da177e4 LT |
878 | shm_unlock(shp); |
879 | ||
bc56bba8 EB |
880 | err = -ENOMEM; |
881 | sfd = kzalloc(sizeof(*sfd), GFP_KERNEL); | |
882 | if (!sfd) | |
ce8d2cdf | 883 | goto out_put_dentry; |
bc56bba8 | 884 | |
ce8d2cdf | 885 | file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations); |
bc56bba8 EB |
886 | if (!file) |
887 | goto out_free; | |
888 | ||
bc56bba8 | 889 | file->private_data = sfd; |
bc56bba8 | 890 | file->f_mapping = shp->shm_file->f_mapping; |
7ca7e564 | 891 | sfd->id = shp->shm_perm.id; |
bc56bba8 EB |
892 | sfd->ns = get_ipc_ns(ns); |
893 | sfd->file = shp->shm_file; | |
894 | sfd->vm_ops = NULL; | |
895 | ||
1da177e4 LT |
896 | down_write(¤t->mm->mmap_sem); |
897 | if (addr && !(shmflg & SHM_REMAP)) { | |
bc56bba8 | 898 | err = -EINVAL; |
1da177e4 LT |
899 | if (find_vma_intersection(current->mm, addr, addr + size)) |
900 | goto invalid; | |
901 | /* | |
902 | * If shm segment goes below stack, make sure there is some | |
903 | * space left for the stack to grow (at least 4 pages). | |
904 | */ | |
905 | if (addr < current->mm->start_stack && | |
906 | addr > current->mm->start_stack - size - PAGE_SIZE * 5) | |
907 | goto invalid; | |
908 | } | |
909 | ||
bc56bba8 EB |
910 | user_addr = do_mmap (file, addr, size, prot, flags, 0); |
911 | *raddr = user_addr; | |
912 | err = 0; | |
913 | if (IS_ERR_VALUE(user_addr)) | |
914 | err = (long)user_addr; | |
1da177e4 LT |
915 | invalid: |
916 | up_write(¤t->mm->mmap_sem); | |
917 | ||
bc56bba8 EB |
918 | fput(file); |
919 | ||
920 | out_nattch: | |
3e148c79 | 921 | down_write(&shm_ids(ns).rw_mutex); |
00c2bf85 | 922 | shp = shm_lock(ns, shmid); |
023a5355 | 923 | BUG_ON(IS_ERR(shp)); |
1da177e4 LT |
924 | shp->shm_nattch--; |
925 | if(shp->shm_nattch == 0 && | |
b33291c0 | 926 | shp->shm_perm.mode & SHM_DEST) |
4e982311 | 927 | shm_destroy(ns, shp); |
1da177e4 LT |
928 | else |
929 | shm_unlock(shp); | |
3e148c79 | 930 | up_write(&shm_ids(ns).rw_mutex); |
1da177e4 | 931 | |
1da177e4 LT |
932 | out: |
933 | return err; | |
bc56bba8 EB |
934 | |
935 | out_unlock: | |
936 | shm_unlock(shp); | |
937 | goto out; | |
938 | ||
939 | out_free: | |
940 | kfree(sfd); | |
ce8d2cdf | 941 | out_put_dentry: |
bc56bba8 | 942 | dput(path.dentry); |
bc56bba8 | 943 | goto out_nattch; |
1da177e4 LT |
944 | } |
945 | ||
d5460c99 | 946 | SYSCALL_DEFINE3(shmat, int, shmid, char __user *, shmaddr, int, shmflg) |
7d87e14c SR |
947 | { |
948 | unsigned long ret; | |
949 | long err; | |
950 | ||
951 | err = do_shmat(shmid, shmaddr, shmflg, &ret); | |
952 | if (err) | |
953 | return err; | |
954 | force_successful_syscall_return(); | |
955 | return (long)ret; | |
956 | } | |
957 | ||
1da177e4 LT |
958 | /* |
959 | * detach and kill segment if marked destroyed. | |
960 | * The work is done in shm_close. | |
961 | */ | |
d5460c99 | 962 | SYSCALL_DEFINE1(shmdt, char __user *, shmaddr) |
1da177e4 LT |
963 | { |
964 | struct mm_struct *mm = current->mm; | |
965 | struct vm_area_struct *vma, *next; | |
966 | unsigned long addr = (unsigned long)shmaddr; | |
967 | loff_t size = 0; | |
968 | int retval = -EINVAL; | |
969 | ||
df1e2fb5 HD |
970 | if (addr & ~PAGE_MASK) |
971 | return retval; | |
972 | ||
1da177e4 LT |
973 | down_write(&mm->mmap_sem); |
974 | ||
975 | /* | |
976 | * This function tries to be smart and unmap shm segments that | |
977 | * were modified by partial mlock or munmap calls: | |
978 | * - It first determines the size of the shm segment that should be | |
979 | * unmapped: It searches for a vma that is backed by shm and that | |
980 | * started at address shmaddr. It records it's size and then unmaps | |
981 | * it. | |
982 | * - Then it unmaps all shm vmas that started at shmaddr and that | |
983 | * are within the initially determined size. | |
984 | * Errors from do_munmap are ignored: the function only fails if | |
985 | * it's called with invalid parameters or if it's called to unmap | |
986 | * a part of a vma. Both calls in this function are for full vmas, | |
987 | * the parameters are directly copied from the vma itself and always | |
988 | * valid - therefore do_munmap cannot fail. (famous last words?) | |
989 | */ | |
990 | /* | |
991 | * If it had been mremap()'d, the starting address would not | |
992 | * match the usual checks anyway. So assume all vma's are | |
993 | * above the starting address given. | |
994 | */ | |
995 | vma = find_vma(mm, addr); | |
996 | ||
8feae131 | 997 | #ifdef CONFIG_MMU |
1da177e4 LT |
998 | while (vma) { |
999 | next = vma->vm_next; | |
1000 | ||
1001 | /* | |
1002 | * Check if the starting address would match, i.e. it's | |
1003 | * a fragment created by mprotect() and/or munmap(), or it | |
1004 | * otherwise it starts at this address with no hassles. | |
1005 | */ | |
bc56bba8 | 1006 | if ((vma->vm_ops == &shm_vm_ops) && |
1da177e4 LT |
1007 | (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) { |
1008 | ||
1009 | ||
6d63079a | 1010 | size = vma->vm_file->f_path.dentry->d_inode->i_size; |
1da177e4 LT |
1011 | do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start); |
1012 | /* | |
1013 | * We discovered the size of the shm segment, so | |
1014 | * break out of here and fall through to the next | |
1015 | * loop that uses the size information to stop | |
1016 | * searching for matching vma's. | |
1017 | */ | |
1018 | retval = 0; | |
1019 | vma = next; | |
1020 | break; | |
1021 | } | |
1022 | vma = next; | |
1023 | } | |
1024 | ||
1025 | /* | |
1026 | * We need look no further than the maximum address a fragment | |
1027 | * could possibly have landed at. Also cast things to loff_t to | |
1028 | * prevent overflows and make comparisions vs. equal-width types. | |
1029 | */ | |
8e36709d | 1030 | size = PAGE_ALIGN(size); |
1da177e4 LT |
1031 | while (vma && (loff_t)(vma->vm_end - addr) <= size) { |
1032 | next = vma->vm_next; | |
1033 | ||
1034 | /* finding a matching vma now does not alter retval */ | |
bc56bba8 | 1035 | if ((vma->vm_ops == &shm_vm_ops) && |
1da177e4 LT |
1036 | (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) |
1037 | ||
1038 | do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start); | |
1039 | vma = next; | |
1040 | } | |
1041 | ||
8feae131 DH |
1042 | #else /* CONFIG_MMU */ |
1043 | /* under NOMMU conditions, the exact address to be destroyed must be | |
1044 | * given */ | |
1045 | retval = -EINVAL; | |
1046 | if (vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) { | |
1047 | do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start); | |
1048 | retval = 0; | |
1049 | } | |
1050 | ||
1051 | #endif | |
1052 | ||
1da177e4 LT |
1053 | up_write(&mm->mmap_sem); |
1054 | return retval; | |
1055 | } | |
1056 | ||
1057 | #ifdef CONFIG_PROC_FS | |
19b4946c | 1058 | static int sysvipc_shm_proc_show(struct seq_file *s, void *it) |
1da177e4 | 1059 | { |
19b4946c | 1060 | struct shmid_kernel *shp = it; |
1da177e4 | 1061 | |
6c826818 PM |
1062 | #if BITS_PER_LONG <= 32 |
1063 | #define SIZE_SPEC "%10lu" | |
1064 | #else | |
1065 | #define SIZE_SPEC "%21lu" | |
1066 | #endif | |
1da177e4 | 1067 | |
6c826818 PM |
1068 | return seq_printf(s, |
1069 | "%10d %10d %4o " SIZE_SPEC " %5u %5u " | |
1070 | "%5lu %5u %5u %5u %5u %10lu %10lu %10lu\n", | |
19b4946c | 1071 | shp->shm_perm.key, |
7ca7e564 | 1072 | shp->shm_perm.id, |
b33291c0 | 1073 | shp->shm_perm.mode, |
19b4946c MW |
1074 | shp->shm_segsz, |
1075 | shp->shm_cprid, | |
1076 | shp->shm_lprid, | |
bc56bba8 | 1077 | shp->shm_nattch, |
19b4946c MW |
1078 | shp->shm_perm.uid, |
1079 | shp->shm_perm.gid, | |
1080 | shp->shm_perm.cuid, | |
1081 | shp->shm_perm.cgid, | |
1082 | shp->shm_atim, | |
1083 | shp->shm_dtim, | |
1084 | shp->shm_ctim); | |
1da177e4 LT |
1085 | } |
1086 | #endif |