Commit | Line | Data |
---|---|---|
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> |
5f921ae9 | 38 | #include <linux/mutex.h> |
4e982311 | 39 | #include <linux/nsproxy.h> |
bc56bba8 | 40 | #include <linux/mount.h> |
7d87e14c | 41 | |
1da177e4 LT |
42 | #include <asm/uaccess.h> |
43 | ||
44 | #include "util.h" | |
45 | ||
bc56bba8 EB |
46 | struct shm_file_data { |
47 | int id; | |
48 | struct ipc_namespace *ns; | |
49 | struct file *file; | |
50 | const struct vm_operations_struct *vm_ops; | |
51 | }; | |
52 | ||
53 | #define shm_file_data(file) (*((struct shm_file_data **)&(file)->private_data)) | |
54 | ||
9a32144e | 55 | static const struct file_operations shm_file_operations; |
1da177e4 LT |
56 | static struct vm_operations_struct shm_vm_ops; |
57 | ||
4e982311 KK |
58 | static struct ipc_ids init_shm_ids; |
59 | ||
60 | #define shm_ids(ns) (*((ns)->ids[IPC_SHM_IDS])) | |
1da177e4 | 61 | |
4e982311 KK |
62 | #define shm_lock(ns, id) \ |
63 | ((struct shmid_kernel*)ipc_lock(&shm_ids(ns),id)) | |
64 | #define shm_unlock(shp) \ | |
65 | ipc_unlock(&(shp)->shm_perm) | |
4e982311 KK |
66 | #define shm_buildid(ns, id, seq) \ |
67 | ipc_buildid(&shm_ids(ns), id, seq) | |
1da177e4 | 68 | |
7748dbfa | 69 | static int newseg(struct ipc_namespace *, struct ipc_params *); |
bc56bba8 EB |
70 | static void shm_open(struct vm_area_struct *vma); |
71 | static void shm_close(struct vm_area_struct *vma); | |
4e982311 | 72 | static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp); |
1da177e4 | 73 | #ifdef CONFIG_PROC_FS |
19b4946c | 74 | static int sysvipc_shm_proc_show(struct seq_file *s, void *it); |
1da177e4 LT |
75 | #endif |
76 | ||
7d69a1f4 | 77 | static void __shm_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids) |
4e982311 KK |
78 | { |
79 | ns->ids[IPC_SHM_IDS] = ids; | |
80 | ns->shm_ctlmax = SHMMAX; | |
81 | ns->shm_ctlall = SHMALL; | |
82 | ns->shm_ctlmni = SHMMNI; | |
83 | ns->shm_tot = 0; | |
7ca7e564 | 84 | ipc_init_ids(ids); |
4e982311 KK |
85 | } |
86 | ||
87 | static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp) | |
88 | { | |
89 | if (shp->shm_nattch){ | |
90 | shp->shm_perm.mode |= SHM_DEST; | |
91 | /* Do not find it any more */ | |
92 | shp->shm_perm.key = IPC_PRIVATE; | |
93 | shm_unlock(shp); | |
94 | } else | |
95 | shm_destroy(ns, shp); | |
96 | } | |
97 | ||
4e982311 KK |
98 | int shm_init_ns(struct ipc_namespace *ns) |
99 | { | |
100 | struct ipc_ids *ids; | |
101 | ||
102 | ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL); | |
103 | if (ids == NULL) | |
104 | return -ENOMEM; | |
1da177e4 | 105 | |
4e982311 KK |
106 | __shm_init_ns(ns, ids); |
107 | return 0; | |
108 | } | |
109 | ||
110 | void shm_exit_ns(struct ipc_namespace *ns) | |
111 | { | |
4e982311 | 112 | struct shmid_kernel *shp; |
7ca7e564 ND |
113 | int next_id; |
114 | int total, in_use; | |
4e982311 KK |
115 | |
116 | mutex_lock(&shm_ids(ns).mutex); | |
7ca7e564 ND |
117 | |
118 | in_use = shm_ids(ns).in_use; | |
119 | ||
120 | for (total = 0, next_id = 0; total < in_use; next_id++) { | |
121 | shp = idr_find(&shm_ids(ns).ipcs_idr, next_id); | |
4e982311 KK |
122 | if (shp == NULL) |
123 | continue; | |
7ca7e564 | 124 | ipc_lock_by_ptr(&shp->shm_perm); |
4e982311 | 125 | do_shm_rmid(ns, shp); |
7ca7e564 | 126 | total++; |
4e982311 KK |
127 | } |
128 | mutex_unlock(&shm_ids(ns).mutex); | |
129 | ||
130 | kfree(ns->ids[IPC_SHM_IDS]); | |
131 | ns->ids[IPC_SHM_IDS] = NULL; | |
132 | } | |
1da177e4 LT |
133 | |
134 | void __init shm_init (void) | |
135 | { | |
4e982311 | 136 | __shm_init_ns(&init_ipc_ns, &init_shm_ids); |
19b4946c MW |
137 | ipc_init_proc_interface("sysvipc/shm", |
138 | " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime\n", | |
4e982311 | 139 | IPC_SHM_IDS, sysvipc_shm_proc_show); |
1da177e4 LT |
140 | } |
141 | ||
4e982311 KK |
142 | static inline int shm_checkid(struct ipc_namespace *ns, |
143 | struct shmid_kernel *s, int id) | |
1da177e4 | 144 | { |
4e982311 | 145 | if (ipc_checkid(&shm_ids(ns), &s->shm_perm, id)) |
1da177e4 LT |
146 | return -EIDRM; |
147 | return 0; | |
148 | } | |
149 | ||
7ca7e564 | 150 | static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s) |
1da177e4 | 151 | { |
7ca7e564 | 152 | ipc_rmid(&shm_ids(ns), &s->shm_perm); |
1da177e4 LT |
153 | } |
154 | ||
4e982311 | 155 | static inline int shm_addid(struct ipc_namespace *ns, struct shmid_kernel *shp) |
1da177e4 | 156 | { |
4e982311 | 157 | return ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni); |
1da177e4 LT |
158 | } |
159 | ||
160 | ||
161 | ||
bc56bba8 EB |
162 | /* This is called by fork, once for every shm attach. */ |
163 | static void shm_open(struct vm_area_struct *vma) | |
4e982311 | 164 | { |
bc56bba8 EB |
165 | struct file *file = vma->vm_file; |
166 | struct shm_file_data *sfd = shm_file_data(file); | |
1da177e4 LT |
167 | struct shmid_kernel *shp; |
168 | ||
bc56bba8 | 169 | shp = shm_lock(sfd->ns, sfd->id); |
9ba025f1 | 170 | BUG_ON(!shp); |
1da177e4 | 171 | shp->shm_atim = get_seconds(); |
b488893a | 172 | shp->shm_lprid = task_tgid_vnr(current); |
1da177e4 LT |
173 | shp->shm_nattch++; |
174 | shm_unlock(shp); | |
175 | } | |
176 | ||
1da177e4 LT |
177 | /* |
178 | * shm_destroy - free the struct shmid_kernel | |
179 | * | |
180 | * @shp: struct to free | |
181 | * | |
5f921ae9 | 182 | * It has to be called with shp and shm_ids.mutex locked, |
1da177e4 LT |
183 | * but returns with shp unlocked and freed. |
184 | */ | |
4e982311 | 185 | static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp) |
1da177e4 | 186 | { |
4e982311 | 187 | ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT; |
7ca7e564 | 188 | shm_rmid(ns, shp); |
1da177e4 LT |
189 | shm_unlock(shp); |
190 | if (!is_file_hugepages(shp->shm_file)) | |
191 | shmem_lock(shp->shm_file, 0, shp->mlock_user); | |
192 | else | |
6d63079a | 193 | user_shm_unlock(shp->shm_file->f_path.dentry->d_inode->i_size, |
1da177e4 LT |
194 | shp->mlock_user); |
195 | fput (shp->shm_file); | |
196 | security_shm_free(shp); | |
197 | ipc_rcu_putref(shp); | |
198 | } | |
199 | ||
200 | /* | |
bc56bba8 | 201 | * remove the attach descriptor vma. |
1da177e4 LT |
202 | * free memory for segment if it is marked destroyed. |
203 | * The descriptor has already been removed from the current->mm->mmap list | |
204 | * and will later be kfree()d. | |
205 | */ | |
bc56bba8 | 206 | static void shm_close(struct vm_area_struct *vma) |
1da177e4 | 207 | { |
bc56bba8 EB |
208 | struct file * file = vma->vm_file; |
209 | struct shm_file_data *sfd = shm_file_data(file); | |
1da177e4 | 210 | struct shmid_kernel *shp; |
bc56bba8 | 211 | struct ipc_namespace *ns = sfd->ns; |
4e982311 KK |
212 | |
213 | mutex_lock(&shm_ids(ns).mutex); | |
1da177e4 | 214 | /* remove from the list of attaches of the shm segment */ |
bc56bba8 | 215 | shp = shm_lock(ns, sfd->id); |
9ba025f1 | 216 | BUG_ON(!shp); |
b488893a | 217 | shp->shm_lprid = task_tgid_vnr(current); |
1da177e4 LT |
218 | shp->shm_dtim = get_seconds(); |
219 | shp->shm_nattch--; | |
220 | if(shp->shm_nattch == 0 && | |
b33291c0 | 221 | shp->shm_perm.mode & SHM_DEST) |
4e982311 | 222 | shm_destroy(ns, shp); |
1da177e4 LT |
223 | else |
224 | shm_unlock(shp); | |
4e982311 | 225 | mutex_unlock(&shm_ids(ns).mutex); |
1da177e4 LT |
226 | } |
227 | ||
d0217ac0 | 228 | static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
bc56bba8 EB |
229 | { |
230 | struct file *file = vma->vm_file; | |
231 | struct shm_file_data *sfd = shm_file_data(file); | |
232 | ||
d0217ac0 | 233 | return sfd->vm_ops->fault(vma, vmf); |
bc56bba8 EB |
234 | } |
235 | ||
236 | #ifdef CONFIG_NUMA | |
d823e3e7 | 237 | static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new) |
bc56bba8 EB |
238 | { |
239 | struct file *file = vma->vm_file; | |
240 | struct shm_file_data *sfd = shm_file_data(file); | |
241 | int err = 0; | |
242 | if (sfd->vm_ops->set_policy) | |
243 | err = sfd->vm_ops->set_policy(vma, new); | |
244 | return err; | |
245 | } | |
246 | ||
d823e3e7 AB |
247 | static struct mempolicy *shm_get_policy(struct vm_area_struct *vma, |
248 | unsigned long addr) | |
bc56bba8 EB |
249 | { |
250 | struct file *file = vma->vm_file; | |
251 | struct shm_file_data *sfd = shm_file_data(file); | |
252 | struct mempolicy *pol = NULL; | |
253 | ||
254 | if (sfd->vm_ops->get_policy) | |
255 | pol = sfd->vm_ops->get_policy(vma, addr); | |
22741925 | 256 | else if (vma->vm_policy) |
bc56bba8 | 257 | pol = vma->vm_policy; |
22741925 AL |
258 | else |
259 | pol = current->mempolicy; | |
bc56bba8 EB |
260 | return pol; |
261 | } | |
262 | #endif | |
263 | ||
1da177e4 LT |
264 | static int shm_mmap(struct file * file, struct vm_area_struct * vma) |
265 | { | |
bc56bba8 | 266 | struct shm_file_data *sfd = shm_file_data(file); |
b0e15190 DH |
267 | int ret; |
268 | ||
bc56bba8 EB |
269 | ret = sfd->file->f_op->mmap(sfd->file, vma); |
270 | if (ret != 0) | |
271 | return ret; | |
272 | sfd->vm_ops = vma->vm_ops; | |
2e92a3ba | 273 | #ifdef CONFIG_MMU |
54cb8821 | 274 | BUG_ON(!sfd->vm_ops->fault); |
2e92a3ba | 275 | #endif |
bc56bba8 EB |
276 | vma->vm_ops = &shm_vm_ops; |
277 | shm_open(vma); | |
b0e15190 DH |
278 | |
279 | return ret; | |
1da177e4 LT |
280 | } |
281 | ||
4e982311 KK |
282 | static int shm_release(struct inode *ino, struct file *file) |
283 | { | |
bc56bba8 | 284 | struct shm_file_data *sfd = shm_file_data(file); |
4e982311 | 285 | |
bc56bba8 EB |
286 | put_ipc_ns(sfd->ns); |
287 | shm_file_data(file) = NULL; | |
288 | kfree(sfd); | |
4e982311 KK |
289 | return 0; |
290 | } | |
291 | ||
516dffdc AL |
292 | static int shm_fsync(struct file *file, struct dentry *dentry, int datasync) |
293 | { | |
294 | int (*fsync) (struct file *, struct dentry *, int datasync); | |
295 | struct shm_file_data *sfd = shm_file_data(file); | |
296 | int ret = -EINVAL; | |
297 | ||
298 | fsync = sfd->file->f_op->fsync; | |
299 | if (fsync) | |
300 | ret = fsync(sfd->file, sfd->file->f_path.dentry, datasync); | |
301 | return ret; | |
302 | } | |
303 | ||
bc56bba8 EB |
304 | static unsigned long shm_get_unmapped_area(struct file *file, |
305 | unsigned long addr, unsigned long len, unsigned long pgoff, | |
306 | unsigned long flags) | |
307 | { | |
308 | struct shm_file_data *sfd = shm_file_data(file); | |
516dffdc AL |
309 | return get_unmapped_area(sfd->file, addr, len, pgoff, flags); |
310 | } | |
311 | ||
312 | int is_file_shm_hugepages(struct file *file) | |
313 | { | |
314 | int ret = 0; | |
315 | ||
316 | if (file->f_op == &shm_file_operations) { | |
317 | struct shm_file_data *sfd; | |
318 | sfd = shm_file_data(file); | |
319 | ret = is_file_hugepages(sfd->file); | |
320 | } | |
321 | return ret; | |
bc56bba8 | 322 | } |
bc56bba8 | 323 | |
9a32144e | 324 | static const struct file_operations shm_file_operations = { |
4e982311 | 325 | .mmap = shm_mmap, |
516dffdc | 326 | .fsync = shm_fsync, |
4e982311 | 327 | .release = shm_release, |
bc56bba8 | 328 | .get_unmapped_area = shm_get_unmapped_area, |
1da177e4 LT |
329 | }; |
330 | ||
331 | static struct vm_operations_struct shm_vm_ops = { | |
332 | .open = shm_open, /* callback for a new vm-area open */ | |
333 | .close = shm_close, /* callback for when the vm-area is released */ | |
54cb8821 | 334 | .fault = shm_fault, |
bc56bba8 EB |
335 | #if defined(CONFIG_NUMA) |
336 | .set_policy = shm_set_policy, | |
337 | .get_policy = shm_get_policy, | |
1da177e4 LT |
338 | #endif |
339 | }; | |
340 | ||
7748dbfa | 341 | static int newseg(struct ipc_namespace *ns, struct ipc_params *params) |
1da177e4 | 342 | { |
7748dbfa ND |
343 | key_t key = params->key; |
344 | int shmflg = params->flg; | |
345 | size_t size = params->u.size; | |
1da177e4 LT |
346 | int error; |
347 | struct shmid_kernel *shp; | |
348 | int numpages = (size + PAGE_SIZE -1) >> PAGE_SHIFT; | |
349 | struct file * file; | |
350 | char name[13]; | |
351 | int id; | |
352 | ||
4e982311 | 353 | if (size < SHMMIN || size > ns->shm_ctlmax) |
1da177e4 LT |
354 | return -EINVAL; |
355 | ||
f66d45e9 | 356 | if (ns->shm_tot + numpages > ns->shm_ctlall) |
1da177e4 LT |
357 | return -ENOSPC; |
358 | ||
359 | shp = ipc_rcu_alloc(sizeof(*shp)); | |
360 | if (!shp) | |
361 | return -ENOMEM; | |
362 | ||
363 | shp->shm_perm.key = key; | |
b33291c0 | 364 | shp->shm_perm.mode = (shmflg & S_IRWXUGO); |
1da177e4 LT |
365 | shp->mlock_user = NULL; |
366 | ||
367 | shp->shm_perm.security = NULL; | |
368 | error = security_shm_alloc(shp); | |
369 | if (error) { | |
370 | ipc_rcu_putref(shp); | |
371 | return error; | |
372 | } | |
373 | ||
9d66586f | 374 | sprintf (name, "SYSV%08x", key); |
1da177e4 | 375 | if (shmflg & SHM_HUGETLB) { |
9d66586f EB |
376 | /* hugetlb_file_setup takes care of mlock user accounting */ |
377 | file = hugetlb_file_setup(name, size); | |
1da177e4 LT |
378 | shp->mlock_user = current->user; |
379 | } else { | |
bf8f972d BP |
380 | int acctflag = VM_ACCOUNT; |
381 | /* | |
382 | * Do not allow no accounting for OVERCOMMIT_NEVER, even | |
383 | * if it's asked for. | |
384 | */ | |
385 | if ((shmflg & SHM_NORESERVE) && | |
386 | sysctl_overcommit_memory != OVERCOMMIT_NEVER) | |
387 | acctflag = 0; | |
bf8f972d | 388 | file = shmem_file_setup(name, size, acctflag); |
1da177e4 LT |
389 | } |
390 | error = PTR_ERR(file); | |
391 | if (IS_ERR(file)) | |
392 | goto no_file; | |
393 | ||
394 | error = -ENOSPC; | |
4e982311 | 395 | id = shm_addid(ns, shp); |
1da177e4 LT |
396 | if(id == -1) |
397 | goto no_id; | |
398 | ||
b488893a | 399 | shp->shm_cprid = task_tgid_vnr(current); |
1da177e4 LT |
400 | shp->shm_lprid = 0; |
401 | shp->shm_atim = shp->shm_dtim = 0; | |
402 | shp->shm_ctim = get_seconds(); | |
403 | shp->shm_segsz = size; | |
404 | shp->shm_nattch = 0; | |
7ca7e564 | 405 | shp->shm_perm.id = shm_buildid(ns, id, shp->shm_perm.seq); |
1da177e4 | 406 | shp->shm_file = file; |
30475cc1 BP |
407 | /* |
408 | * shmid gets reported as "inode#" in /proc/pid/maps. | |
409 | * proc-ps tools use this. Changing this will break them. | |
410 | */ | |
7ca7e564 | 411 | file->f_dentry->d_inode->i_ino = shp->shm_perm.id; |
551110a9 | 412 | |
4e982311 | 413 | ns->shm_tot += numpages; |
7ca7e564 | 414 | error = shp->shm_perm.id; |
1da177e4 | 415 | shm_unlock(shp); |
7ca7e564 | 416 | return error; |
1da177e4 LT |
417 | |
418 | no_id: | |
419 | fput(file); | |
420 | no_file: | |
421 | security_shm_free(shp); | |
422 | ipc_rcu_putref(shp); | |
423 | return error; | |
424 | } | |
425 | ||
7748dbfa ND |
426 | static inline int shm_security(void *shp, int shmflg) |
427 | { | |
428 | return security_shm_associate((struct shmid_kernel *) shp, shmflg); | |
429 | } | |
430 | ||
431 | static inline int shm_more_checks(void *shp, struct ipc_params *params) | |
432 | { | |
433 | if (((struct shmid_kernel *)shp)->shm_segsz < params->u.size) | |
434 | return -EINVAL; | |
435 | ||
436 | return 0; | |
437 | } | |
438 | ||
1da177e4 LT |
439 | asmlinkage long sys_shmget (key_t key, size_t size, int shmflg) |
440 | { | |
4e982311 | 441 | struct ipc_namespace *ns; |
7748dbfa ND |
442 | struct ipc_ops shm_ops; |
443 | struct ipc_params shm_params; | |
4e982311 KK |
444 | |
445 | ns = current->nsproxy->ipc_ns; | |
1da177e4 | 446 | |
7748dbfa ND |
447 | shm_ops.getnew = newseg; |
448 | shm_ops.associate = shm_security; | |
449 | shm_ops.more_checks = shm_more_checks; | |
7ca7e564 | 450 | |
7748dbfa ND |
451 | shm_params.key = key; |
452 | shm_params.flg = shmflg; | |
453 | shm_params.u.size = size; | |
1da177e4 | 454 | |
7748dbfa | 455 | return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params); |
1da177e4 LT |
456 | } |
457 | ||
458 | static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version) | |
459 | { | |
460 | switch(version) { | |
461 | case IPC_64: | |
462 | return copy_to_user(buf, in, sizeof(*in)); | |
463 | case IPC_OLD: | |
464 | { | |
465 | struct shmid_ds out; | |
466 | ||
467 | ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm); | |
468 | out.shm_segsz = in->shm_segsz; | |
469 | out.shm_atime = in->shm_atime; | |
470 | out.shm_dtime = in->shm_dtime; | |
471 | out.shm_ctime = in->shm_ctime; | |
472 | out.shm_cpid = in->shm_cpid; | |
473 | out.shm_lpid = in->shm_lpid; | |
474 | out.shm_nattch = in->shm_nattch; | |
475 | ||
476 | return copy_to_user(buf, &out, sizeof(out)); | |
477 | } | |
478 | default: | |
479 | return -EINVAL; | |
480 | } | |
481 | } | |
482 | ||
483 | struct shm_setbuf { | |
484 | uid_t uid; | |
485 | gid_t gid; | |
486 | mode_t mode; | |
487 | }; | |
488 | ||
489 | static inline unsigned long copy_shmid_from_user(struct shm_setbuf *out, void __user *buf, int version) | |
490 | { | |
491 | switch(version) { | |
492 | case IPC_64: | |
493 | { | |
494 | struct shmid64_ds tbuf; | |
495 | ||
496 | if (copy_from_user(&tbuf, buf, sizeof(tbuf))) | |
497 | return -EFAULT; | |
498 | ||
499 | out->uid = tbuf.shm_perm.uid; | |
500 | out->gid = tbuf.shm_perm.gid; | |
b33291c0 | 501 | out->mode = tbuf.shm_perm.mode; |
1da177e4 LT |
502 | |
503 | return 0; | |
504 | } | |
505 | case IPC_OLD: | |
506 | { | |
507 | struct shmid_ds tbuf_old; | |
508 | ||
509 | if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) | |
510 | return -EFAULT; | |
511 | ||
512 | out->uid = tbuf_old.shm_perm.uid; | |
513 | out->gid = tbuf_old.shm_perm.gid; | |
b33291c0 | 514 | out->mode = tbuf_old.shm_perm.mode; |
1da177e4 LT |
515 | |
516 | return 0; | |
517 | } | |
518 | default: | |
519 | return -EINVAL; | |
520 | } | |
521 | } | |
522 | ||
523 | static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminfo64 *in, int version) | |
524 | { | |
525 | switch(version) { | |
526 | case IPC_64: | |
527 | return copy_to_user(buf, in, sizeof(*in)); | |
528 | case IPC_OLD: | |
529 | { | |
530 | struct shminfo out; | |
531 | ||
532 | if(in->shmmax > INT_MAX) | |
533 | out.shmmax = INT_MAX; | |
534 | else | |
535 | out.shmmax = (int)in->shmmax; | |
536 | ||
537 | out.shmmin = in->shmmin; | |
538 | out.shmmni = in->shmmni; | |
539 | out.shmseg = in->shmseg; | |
540 | out.shmall = in->shmall; | |
541 | ||
542 | return copy_to_user(buf, &out, sizeof(out)); | |
543 | } | |
544 | default: | |
545 | return -EINVAL; | |
546 | } | |
547 | } | |
548 | ||
4e982311 KK |
549 | static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss, |
550 | unsigned long *swp) | |
1da177e4 | 551 | { |
7ca7e564 ND |
552 | int next_id; |
553 | int total, in_use; | |
1da177e4 LT |
554 | |
555 | *rss = 0; | |
556 | *swp = 0; | |
557 | ||
7ca7e564 ND |
558 | in_use = shm_ids(ns).in_use; |
559 | ||
560 | for (total = 0, next_id = 0; total < in_use; next_id++) { | |
1da177e4 LT |
561 | struct shmid_kernel *shp; |
562 | struct inode *inode; | |
563 | ||
637c3663 ND |
564 | /* |
565 | * idr_find() is called via shm_get(), so with shm_ids.mutex | |
566 | * locked. Since ipc_addid() is also called with | |
567 | * shm_ids.mutex down, there is no need to add read barriers | |
568 | * here to gurantee the writes in ipc_addid() are seen in | |
569 | * order here (for Alpha). | |
570 | * However idr_find() itself does not necessary require | |
571 | * ipc_ids.mutex down. So if idr_find() is used by other | |
572 | * places without ipc_ids.mutex down, then it needs read | |
573 | * read memory barriers as ipc_lock() does. | |
574 | */ | |
575 | ||
576 | shp = idr_find(&shm_ids(ns).ipcs_idr, next_id); | |
7ca7e564 | 577 | if (shp == NULL) |
1da177e4 LT |
578 | continue; |
579 | ||
6d63079a | 580 | inode = shp->shm_file->f_path.dentry->d_inode; |
1da177e4 LT |
581 | |
582 | if (is_file_hugepages(shp->shm_file)) { | |
583 | struct address_space *mapping = inode->i_mapping; | |
584 | *rss += (HPAGE_SIZE/PAGE_SIZE)*mapping->nrpages; | |
585 | } else { | |
586 | struct shmem_inode_info *info = SHMEM_I(inode); | |
587 | spin_lock(&info->lock); | |
588 | *rss += inode->i_mapping->nrpages; | |
589 | *swp += info->swapped; | |
590 | spin_unlock(&info->lock); | |
591 | } | |
7ca7e564 ND |
592 | |
593 | total++; | |
1da177e4 LT |
594 | } |
595 | } | |
596 | ||
597 | asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf) | |
598 | { | |
599 | struct shm_setbuf setbuf; | |
600 | struct shmid_kernel *shp; | |
601 | int err, version; | |
4e982311 | 602 | struct ipc_namespace *ns; |
1da177e4 LT |
603 | |
604 | if (cmd < 0 || shmid < 0) { | |
605 | err = -EINVAL; | |
606 | goto out; | |
607 | } | |
608 | ||
609 | version = ipc_parse_version(&cmd); | |
4e982311 | 610 | ns = current->nsproxy->ipc_ns; |
1da177e4 LT |
611 | |
612 | switch (cmd) { /* replace with proc interface ? */ | |
613 | case IPC_INFO: | |
614 | { | |
615 | struct shminfo64 shminfo; | |
616 | ||
617 | err = security_shm_shmctl(NULL, cmd); | |
618 | if (err) | |
619 | return err; | |
620 | ||
621 | memset(&shminfo,0,sizeof(shminfo)); | |
4e982311 KK |
622 | shminfo.shmmni = shminfo.shmseg = ns->shm_ctlmni; |
623 | shminfo.shmmax = ns->shm_ctlmax; | |
624 | shminfo.shmall = ns->shm_ctlall; | |
1da177e4 LT |
625 | |
626 | shminfo.shmmin = SHMMIN; | |
627 | if(copy_shminfo_to_user (buf, &shminfo, version)) | |
628 | return -EFAULT; | |
629 | /* reading a integer is always atomic */ | |
7ca7e564 | 630 | err = ipc_get_maxid(&shm_ids(ns)); |
1da177e4 LT |
631 | if(err<0) |
632 | err = 0; | |
633 | goto out; | |
634 | } | |
635 | case SHM_INFO: | |
636 | { | |
637 | struct shm_info shm_info; | |
638 | ||
639 | err = security_shm_shmctl(NULL, cmd); | |
640 | if (err) | |
641 | return err; | |
642 | ||
643 | memset(&shm_info,0,sizeof(shm_info)); | |
4e982311 KK |
644 | mutex_lock(&shm_ids(ns).mutex); |
645 | shm_info.used_ids = shm_ids(ns).in_use; | |
646 | shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp); | |
647 | shm_info.shm_tot = ns->shm_tot; | |
1da177e4 LT |
648 | shm_info.swap_attempts = 0; |
649 | shm_info.swap_successes = 0; | |
7ca7e564 | 650 | err = ipc_get_maxid(&shm_ids(ns)); |
4e982311 | 651 | mutex_unlock(&shm_ids(ns).mutex); |
1da177e4 LT |
652 | if(copy_to_user (buf, &shm_info, sizeof(shm_info))) { |
653 | err = -EFAULT; | |
654 | goto out; | |
655 | } | |
656 | ||
657 | err = err < 0 ? 0 : err; | |
658 | goto out; | |
659 | } | |
660 | case SHM_STAT: | |
661 | case IPC_STAT: | |
662 | { | |
663 | struct shmid64_ds tbuf; | |
664 | int result; | |
665 | memset(&tbuf, 0, sizeof(tbuf)); | |
4e982311 | 666 | shp = shm_lock(ns, shmid); |
1da177e4 LT |
667 | if(shp==NULL) { |
668 | err = -EINVAL; | |
669 | goto out; | |
7ca7e564 ND |
670 | } else if (cmd == SHM_STAT) { |
671 | result = shp->shm_perm.id; | |
1da177e4 | 672 | } else { |
4e982311 | 673 | err = shm_checkid(ns, shp,shmid); |
1da177e4 LT |
674 | if(err) |
675 | goto out_unlock; | |
676 | result = 0; | |
677 | } | |
678 | err=-EACCES; | |
679 | if (ipcperms (&shp->shm_perm, S_IRUGO)) | |
680 | goto out_unlock; | |
681 | err = security_shm_shmctl(shp, cmd); | |
682 | if (err) | |
683 | goto out_unlock; | |
684 | kernel_to_ipc64_perm(&shp->shm_perm, &tbuf.shm_perm); | |
685 | tbuf.shm_segsz = shp->shm_segsz; | |
686 | tbuf.shm_atime = shp->shm_atim; | |
687 | tbuf.shm_dtime = shp->shm_dtim; | |
688 | tbuf.shm_ctime = shp->shm_ctim; | |
689 | tbuf.shm_cpid = shp->shm_cprid; | |
690 | tbuf.shm_lpid = shp->shm_lprid; | |
bc56bba8 | 691 | tbuf.shm_nattch = shp->shm_nattch; |
1da177e4 LT |
692 | shm_unlock(shp); |
693 | if(copy_shmid_to_user (buf, &tbuf, version)) | |
694 | err = -EFAULT; | |
695 | else | |
696 | err = result; | |
697 | goto out; | |
698 | } | |
699 | case SHM_LOCK: | |
700 | case SHM_UNLOCK: | |
701 | { | |
4e982311 | 702 | shp = shm_lock(ns, shmid); |
1da177e4 LT |
703 | if(shp==NULL) { |
704 | err = -EINVAL; | |
705 | goto out; | |
706 | } | |
4e982311 | 707 | err = shm_checkid(ns, shp,shmid); |
1da177e4 LT |
708 | if(err) |
709 | goto out_unlock; | |
710 | ||
073115d6 SG |
711 | err = audit_ipc_obj(&(shp->shm_perm)); |
712 | if (err) | |
713 | goto out_unlock; | |
714 | ||
1da177e4 LT |
715 | if (!capable(CAP_IPC_LOCK)) { |
716 | err = -EPERM; | |
717 | if (current->euid != shp->shm_perm.uid && | |
718 | current->euid != shp->shm_perm.cuid) | |
719 | goto out_unlock; | |
720 | if (cmd == SHM_LOCK && | |
721 | !current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur) | |
722 | goto out_unlock; | |
723 | } | |
724 | ||
725 | err = security_shm_shmctl(shp, cmd); | |
726 | if (err) | |
727 | goto out_unlock; | |
728 | ||
729 | if(cmd==SHM_LOCK) { | |
730 | struct user_struct * user = current->user; | |
731 | if (!is_file_hugepages(shp->shm_file)) { | |
732 | err = shmem_lock(shp->shm_file, 1, user); | |
7be77e20 | 733 | if (!err && !(shp->shm_perm.mode & SHM_LOCKED)){ |
b33291c0 | 734 | shp->shm_perm.mode |= SHM_LOCKED; |
1da177e4 LT |
735 | shp->mlock_user = user; |
736 | } | |
737 | } | |
738 | } else if (!is_file_hugepages(shp->shm_file)) { | |
739 | shmem_lock(shp->shm_file, 0, shp->mlock_user); | |
b33291c0 | 740 | shp->shm_perm.mode &= ~SHM_LOCKED; |
1da177e4 LT |
741 | shp->mlock_user = NULL; |
742 | } | |
743 | shm_unlock(shp); | |
744 | goto out; | |
745 | } | |
746 | case IPC_RMID: | |
747 | { | |
748 | /* | |
749 | * We cannot simply remove the file. The SVID states | |
750 | * that the block remains until the last person | |
751 | * detaches from it, then is deleted. A shmat() on | |
752 | * an RMID segment is legal in older Linux and if | |
753 | * we change it apps break... | |
754 | * | |
755 | * Instead we set a destroyed flag, and then blow | |
756 | * the name away when the usage hits zero. | |
757 | */ | |
4e982311 KK |
758 | mutex_lock(&shm_ids(ns).mutex); |
759 | shp = shm_lock(ns, shmid); | |
1da177e4 LT |
760 | err = -EINVAL; |
761 | if (shp == NULL) | |
762 | goto out_up; | |
4e982311 | 763 | err = shm_checkid(ns, shp, shmid); |
1da177e4 LT |
764 | if(err) |
765 | goto out_unlock_up; | |
766 | ||
073115d6 SG |
767 | err = audit_ipc_obj(&(shp->shm_perm)); |
768 | if (err) | |
769 | goto out_unlock_up; | |
770 | ||
1da177e4 LT |
771 | if (current->euid != shp->shm_perm.uid && |
772 | current->euid != shp->shm_perm.cuid && | |
773 | !capable(CAP_SYS_ADMIN)) { | |
774 | err=-EPERM; | |
775 | goto out_unlock_up; | |
776 | } | |
777 | ||
778 | err = security_shm_shmctl(shp, cmd); | |
779 | if (err) | |
780 | goto out_unlock_up; | |
781 | ||
4e982311 KK |
782 | do_shm_rmid(ns, shp); |
783 | mutex_unlock(&shm_ids(ns).mutex); | |
1da177e4 LT |
784 | goto out; |
785 | } | |
786 | ||
787 | case IPC_SET: | |
788 | { | |
789 | if (copy_shmid_from_user (&setbuf, buf, version)) { | |
790 | err = -EFAULT; | |
791 | goto out; | |
792 | } | |
4e982311 KK |
793 | mutex_lock(&shm_ids(ns).mutex); |
794 | shp = shm_lock(ns, shmid); | |
1da177e4 LT |
795 | err=-EINVAL; |
796 | if(shp==NULL) | |
797 | goto out_up; | |
4e982311 | 798 | err = shm_checkid(ns, shp,shmid); |
1da177e4 LT |
799 | if(err) |
800 | goto out_unlock_up; | |
073115d6 SG |
801 | err = audit_ipc_obj(&(shp->shm_perm)); |
802 | if (err) | |
803 | goto out_unlock_up; | |
ac03221a | 804 | err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode); |
073115d6 SG |
805 | if (err) |
806 | goto out_unlock_up; | |
1da177e4 LT |
807 | err=-EPERM; |
808 | if (current->euid != shp->shm_perm.uid && | |
809 | current->euid != shp->shm_perm.cuid && | |
810 | !capable(CAP_SYS_ADMIN)) { | |
811 | goto out_unlock_up; | |
812 | } | |
813 | ||
814 | err = security_shm_shmctl(shp, cmd); | |
815 | if (err) | |
816 | goto out_unlock_up; | |
817 | ||
818 | shp->shm_perm.uid = setbuf.uid; | |
819 | shp->shm_perm.gid = setbuf.gid; | |
b33291c0 | 820 | shp->shm_perm.mode = (shp->shm_perm.mode & ~S_IRWXUGO) |
1da177e4 LT |
821 | | (setbuf.mode & S_IRWXUGO); |
822 | shp->shm_ctim = get_seconds(); | |
823 | break; | |
824 | } | |
825 | ||
826 | default: | |
827 | err = -EINVAL; | |
828 | goto out; | |
829 | } | |
830 | ||
831 | err = 0; | |
832 | out_unlock_up: | |
833 | shm_unlock(shp); | |
834 | out_up: | |
4e982311 | 835 | mutex_unlock(&shm_ids(ns).mutex); |
1da177e4 LT |
836 | goto out; |
837 | out_unlock: | |
838 | shm_unlock(shp); | |
839 | out: | |
840 | return err; | |
841 | } | |
842 | ||
843 | /* | |
844 | * Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists. | |
845 | * | |
846 | * NOTE! Despite the name, this is NOT a direct system call entrypoint. The | |
847 | * "raddr" thing points to kernel space, and there has to be a wrapper around | |
848 | * this. | |
849 | */ | |
850 | long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr) | |
851 | { | |
852 | struct shmid_kernel *shp; | |
853 | unsigned long addr; | |
854 | unsigned long size; | |
855 | struct file * file; | |
856 | int err; | |
857 | unsigned long flags; | |
858 | unsigned long prot; | |
1da177e4 | 859 | int acc_mode; |
bc56bba8 | 860 | unsigned long user_addr; |
4e982311 | 861 | struct ipc_namespace *ns; |
bc56bba8 EB |
862 | struct shm_file_data *sfd; |
863 | struct path path; | |
864 | mode_t f_mode; | |
1da177e4 | 865 | |
bc56bba8 EB |
866 | err = -EINVAL; |
867 | if (shmid < 0) | |
1da177e4 | 868 | goto out; |
bc56bba8 | 869 | else if ((addr = (ulong)shmaddr)) { |
1da177e4 LT |
870 | if (addr & (SHMLBA-1)) { |
871 | if (shmflg & SHM_RND) | |
872 | addr &= ~(SHMLBA-1); /* round down */ | |
873 | else | |
874 | #ifndef __ARCH_FORCE_SHMLBA | |
875 | if (addr & ~PAGE_MASK) | |
876 | #endif | |
bc56bba8 | 877 | goto out; |
1da177e4 LT |
878 | } |
879 | flags = MAP_SHARED | MAP_FIXED; | |
880 | } else { | |
881 | if ((shmflg & SHM_REMAP)) | |
bc56bba8 | 882 | goto out; |
1da177e4 LT |
883 | |
884 | flags = MAP_SHARED; | |
885 | } | |
886 | ||
887 | if (shmflg & SHM_RDONLY) { | |
888 | prot = PROT_READ; | |
1da177e4 | 889 | acc_mode = S_IRUGO; |
bc56bba8 | 890 | f_mode = FMODE_READ; |
1da177e4 LT |
891 | } else { |
892 | prot = PROT_READ | PROT_WRITE; | |
1da177e4 | 893 | acc_mode = S_IRUGO | S_IWUGO; |
bc56bba8 | 894 | f_mode = FMODE_READ | FMODE_WRITE; |
1da177e4 LT |
895 | } |
896 | if (shmflg & SHM_EXEC) { | |
897 | prot |= PROT_EXEC; | |
898 | acc_mode |= S_IXUGO; | |
899 | } | |
900 | ||
901 | /* | |
902 | * We cannot rely on the fs check since SYSV IPC does have an | |
903 | * additional creator id... | |
904 | */ | |
4e982311 KK |
905 | ns = current->nsproxy->ipc_ns; |
906 | shp = shm_lock(ns, shmid); | |
bc56bba8 | 907 | if(shp == NULL) |
1da177e4 | 908 | goto out; |
bc56bba8 | 909 | |
4e982311 | 910 | err = shm_checkid(ns, shp,shmid); |
bc56bba8 EB |
911 | if (err) |
912 | goto out_unlock; | |
913 | ||
914 | err = -EACCES; | |
915 | if (ipcperms(&shp->shm_perm, acc_mode)) | |
916 | goto out_unlock; | |
1da177e4 LT |
917 | |
918 | err = security_shm_shmat(shp, shmaddr, shmflg); | |
bc56bba8 EB |
919 | if (err) |
920 | goto out_unlock; | |
921 | ||
922 | path.dentry = dget(shp->shm_file->f_path.dentry); | |
ce8d2cdf | 923 | path.mnt = shp->shm_file->f_path.mnt; |
1da177e4 | 924 | shp->shm_nattch++; |
bc56bba8 | 925 | size = i_size_read(path.dentry->d_inode); |
1da177e4 LT |
926 | shm_unlock(shp); |
927 | ||
bc56bba8 EB |
928 | err = -ENOMEM; |
929 | sfd = kzalloc(sizeof(*sfd), GFP_KERNEL); | |
930 | if (!sfd) | |
ce8d2cdf | 931 | goto out_put_dentry; |
bc56bba8 EB |
932 | |
933 | err = -ENOMEM; | |
ce8d2cdf DH |
934 | |
935 | file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations); | |
bc56bba8 EB |
936 | if (!file) |
937 | goto out_free; | |
938 | ||
bc56bba8 | 939 | file->private_data = sfd; |
bc56bba8 | 940 | file->f_mapping = shp->shm_file->f_mapping; |
7ca7e564 | 941 | sfd->id = shp->shm_perm.id; |
bc56bba8 EB |
942 | sfd->ns = get_ipc_ns(ns); |
943 | sfd->file = shp->shm_file; | |
944 | sfd->vm_ops = NULL; | |
945 | ||
1da177e4 LT |
946 | down_write(¤t->mm->mmap_sem); |
947 | if (addr && !(shmflg & SHM_REMAP)) { | |
bc56bba8 | 948 | err = -EINVAL; |
1da177e4 LT |
949 | if (find_vma_intersection(current->mm, addr, addr + size)) |
950 | goto invalid; | |
951 | /* | |
952 | * If shm segment goes below stack, make sure there is some | |
953 | * space left for the stack to grow (at least 4 pages). | |
954 | */ | |
955 | if (addr < current->mm->start_stack && | |
956 | addr > current->mm->start_stack - size - PAGE_SIZE * 5) | |
957 | goto invalid; | |
958 | } | |
959 | ||
bc56bba8 EB |
960 | user_addr = do_mmap (file, addr, size, prot, flags, 0); |
961 | *raddr = user_addr; | |
962 | err = 0; | |
963 | if (IS_ERR_VALUE(user_addr)) | |
964 | err = (long)user_addr; | |
1da177e4 LT |
965 | invalid: |
966 | up_write(¤t->mm->mmap_sem); | |
967 | ||
bc56bba8 EB |
968 | fput(file); |
969 | ||
970 | out_nattch: | |
4e982311 KK |
971 | mutex_lock(&shm_ids(ns).mutex); |
972 | shp = shm_lock(ns, shmid); | |
9ba025f1 | 973 | BUG_ON(!shp); |
1da177e4 LT |
974 | shp->shm_nattch--; |
975 | if(shp->shm_nattch == 0 && | |
b33291c0 | 976 | shp->shm_perm.mode & SHM_DEST) |
4e982311 | 977 | shm_destroy(ns, shp); |
1da177e4 LT |
978 | else |
979 | shm_unlock(shp); | |
4e982311 | 980 | mutex_unlock(&shm_ids(ns).mutex); |
1da177e4 | 981 | |
1da177e4 LT |
982 | out: |
983 | return err; | |
bc56bba8 EB |
984 | |
985 | out_unlock: | |
986 | shm_unlock(shp); | |
987 | goto out; | |
988 | ||
989 | out_free: | |
990 | kfree(sfd); | |
ce8d2cdf | 991 | out_put_dentry: |
bc56bba8 | 992 | dput(path.dentry); |
bc56bba8 | 993 | goto out_nattch; |
1da177e4 LT |
994 | } |
995 | ||
7d87e14c SR |
996 | asmlinkage long sys_shmat(int shmid, char __user *shmaddr, int shmflg) |
997 | { | |
998 | unsigned long ret; | |
999 | long err; | |
1000 | ||
1001 | err = do_shmat(shmid, shmaddr, shmflg, &ret); | |
1002 | if (err) | |
1003 | return err; | |
1004 | force_successful_syscall_return(); | |
1005 | return (long)ret; | |
1006 | } | |
1007 | ||
1da177e4 LT |
1008 | /* |
1009 | * detach and kill segment if marked destroyed. | |
1010 | * The work is done in shm_close. | |
1011 | */ | |
1012 | asmlinkage long sys_shmdt(char __user *shmaddr) | |
1013 | { | |
1014 | struct mm_struct *mm = current->mm; | |
1015 | struct vm_area_struct *vma, *next; | |
1016 | unsigned long addr = (unsigned long)shmaddr; | |
1017 | loff_t size = 0; | |
1018 | int retval = -EINVAL; | |
1019 | ||
df1e2fb5 HD |
1020 | if (addr & ~PAGE_MASK) |
1021 | return retval; | |
1022 | ||
1da177e4 LT |
1023 | down_write(&mm->mmap_sem); |
1024 | ||
1025 | /* | |
1026 | * This function tries to be smart and unmap shm segments that | |
1027 | * were modified by partial mlock or munmap calls: | |
1028 | * - It first determines the size of the shm segment that should be | |
1029 | * unmapped: It searches for a vma that is backed by shm and that | |
1030 | * started at address shmaddr. It records it's size and then unmaps | |
1031 | * it. | |
1032 | * - Then it unmaps all shm vmas that started at shmaddr and that | |
1033 | * are within the initially determined size. | |
1034 | * Errors from do_munmap are ignored: the function only fails if | |
1035 | * it's called with invalid parameters or if it's called to unmap | |
1036 | * a part of a vma. Both calls in this function are for full vmas, | |
1037 | * the parameters are directly copied from the vma itself and always | |
1038 | * valid - therefore do_munmap cannot fail. (famous last words?) | |
1039 | */ | |
1040 | /* | |
1041 | * If it had been mremap()'d, the starting address would not | |
1042 | * match the usual checks anyway. So assume all vma's are | |
1043 | * above the starting address given. | |
1044 | */ | |
1045 | vma = find_vma(mm, addr); | |
1046 | ||
1047 | while (vma) { | |
1048 | next = vma->vm_next; | |
1049 | ||
1050 | /* | |
1051 | * Check if the starting address would match, i.e. it's | |
1052 | * a fragment created by mprotect() and/or munmap(), or it | |
1053 | * otherwise it starts at this address with no hassles. | |
1054 | */ | |
bc56bba8 | 1055 | if ((vma->vm_ops == &shm_vm_ops) && |
1da177e4 LT |
1056 | (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) { |
1057 | ||
1058 | ||
6d63079a | 1059 | size = vma->vm_file->f_path.dentry->d_inode->i_size; |
1da177e4 LT |
1060 | do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start); |
1061 | /* | |
1062 | * We discovered the size of the shm segment, so | |
1063 | * break out of here and fall through to the next | |
1064 | * loop that uses the size information to stop | |
1065 | * searching for matching vma's. | |
1066 | */ | |
1067 | retval = 0; | |
1068 | vma = next; | |
1069 | break; | |
1070 | } | |
1071 | vma = next; | |
1072 | } | |
1073 | ||
1074 | /* | |
1075 | * We need look no further than the maximum address a fragment | |
1076 | * could possibly have landed at. Also cast things to loff_t to | |
1077 | * prevent overflows and make comparisions vs. equal-width types. | |
1078 | */ | |
8e36709d | 1079 | size = PAGE_ALIGN(size); |
1da177e4 LT |
1080 | while (vma && (loff_t)(vma->vm_end - addr) <= size) { |
1081 | next = vma->vm_next; | |
1082 | ||
1083 | /* finding a matching vma now does not alter retval */ | |
bc56bba8 | 1084 | if ((vma->vm_ops == &shm_vm_ops) && |
1da177e4 LT |
1085 | (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) |
1086 | ||
1087 | do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start); | |
1088 | vma = next; | |
1089 | } | |
1090 | ||
1091 | up_write(&mm->mmap_sem); | |
1092 | return retval; | |
1093 | } | |
1094 | ||
1095 | #ifdef CONFIG_PROC_FS | |
19b4946c | 1096 | static int sysvipc_shm_proc_show(struct seq_file *s, void *it) |
1da177e4 | 1097 | { |
19b4946c MW |
1098 | struct shmid_kernel *shp = it; |
1099 | char *format; | |
1da177e4 | 1100 | |
1da177e4 LT |
1101 | #define SMALL_STRING "%10d %10d %4o %10u %5u %5u %5d %5u %5u %5u %5u %10lu %10lu %10lu\n" |
1102 | #define BIG_STRING "%10d %10d %4o %21u %5u %5u %5d %5u %5u %5u %5u %10lu %10lu %10lu\n" | |
1da177e4 | 1103 | |
19b4946c MW |
1104 | if (sizeof(size_t) <= sizeof(int)) |
1105 | format = SMALL_STRING; | |
1106 | else | |
1107 | format = BIG_STRING; | |
1108 | return seq_printf(s, format, | |
1109 | shp->shm_perm.key, | |
7ca7e564 | 1110 | shp->shm_perm.id, |
b33291c0 | 1111 | shp->shm_perm.mode, |
19b4946c MW |
1112 | shp->shm_segsz, |
1113 | shp->shm_cprid, | |
1114 | shp->shm_lprid, | |
bc56bba8 | 1115 | shp->shm_nattch, |
19b4946c MW |
1116 | shp->shm_perm.uid, |
1117 | shp->shm_perm.gid, | |
1118 | shp->shm_perm.cuid, | |
1119 | shp->shm_perm.cgid, | |
1120 | shp->shm_atim, | |
1121 | shp->shm_dtim, | |
1122 | shp->shm_ctim); | |
1da177e4 LT |
1123 | } |
1124 | #endif |