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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>
31#include <linux/shmem_fs.h>
32#include <linux/security.h>
33#include <linux/syscalls.h>
34#include <linux/audit.h>
35#include <linux/capability.h>
36#include <linux/ptrace.h>
37#include <linux/seq_file.h>
38#include <linux/rwsem.h>
39#include <linux/nsproxy.h>
40#include <linux/mount.h>
41#include <linux/ipc_namespace.h>
42
43#include <asm/uaccess.h>
44
45#include "util.h"
46
47struct 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
56static const struct file_operations shm_file_operations;
57static const struct vm_operations_struct shm_vm_ops;
58
59#define shm_ids(ns) ((ns)->ids[IPC_SHM_IDS])
60
61#define shm_unlock(shp) \
62 ipc_unlock(&(shp)->shm_perm)
63
64static int newseg(struct ipc_namespace *, struct ipc_params *);
65static void shm_open(struct vm_area_struct *vma);
66static void shm_close(struct vm_area_struct *vma);
67static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
68#ifdef CONFIG_PROC_FS
69static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
70#endif
71
72void shm_init_ns(struct ipc_namespace *ns)
73{
74 ns->shm_ctlmax = SHMMAX;
75 ns->shm_ctlall = SHMALL;
76 ns->shm_ctlmni = SHMMNI;
77 ns->shm_rmid_forced = 0;
78 ns->shm_tot = 0;
79 ipc_init_ids(&shm_ids(ns));
80}
81
82
83
84
85
86static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
87{
88 struct shmid_kernel *shp;
89 shp = container_of(ipcp, struct shmid_kernel, shm_perm);
90
91 if (shp->shm_nattch){
92 shp->shm_perm.mode |= SHM_DEST;
93
94 shp->shm_perm.key = IPC_PRIVATE;
95 shm_unlock(shp);
96 } else
97 shm_destroy(ns, shp);
98}
99
100#ifdef CONFIG_IPC_NS
101void shm_exit_ns(struct ipc_namespace *ns)
102{
103 free_ipcs(ns, &shm_ids(ns), do_shm_rmid);
104 idr_destroy(&ns->ids[IPC_SHM_IDS].ipcs_idr);
105}
106#endif
107
108static int __init ipc_ns_init(void)
109{
110 shm_init_ns(&init_ipc_ns);
111 return 0;
112}
113
114pure_initcall(ipc_ns_init);
115
116void __init shm_init (void)
117{
118 ipc_init_proc_interface("sysvipc/shm",
119#if BITS_PER_LONG <= 32
120 " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n",
121#else
122 " key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n",
123#endif
124 IPC_SHM_IDS, sysvipc_shm_proc_show);
125}
126
127
128
129
130
131static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
132{
133 struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id);
134
135 if (IS_ERR(ipcp))
136 return (struct shmid_kernel *)ipcp;
137
138 return container_of(ipcp, struct shmid_kernel, shm_perm);
139}
140
141static inline void shm_lock_by_ptr(struct shmid_kernel *ipcp)
142{
143 rcu_read_lock();
144 spin_lock(&ipcp->shm_perm.lock);
145}
146
147static inline struct shmid_kernel *shm_lock_check(struct ipc_namespace *ns,
148 int id)
149{
150 struct kern_ipc_perm *ipcp = ipc_lock_check(&shm_ids(ns), id);
151
152 if (IS_ERR(ipcp))
153 return (struct shmid_kernel *)ipcp;
154
155 return container_of(ipcp, struct shmid_kernel, shm_perm);
156}
157
158static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
159{
160 ipc_rmid(&shm_ids(ns), &s->shm_perm);
161}
162
163
164
165static void shm_open(struct vm_area_struct *vma)
166{
167 struct file *file = vma->vm_file;
168 struct shm_file_data *sfd = shm_file_data(file);
169 struct shmid_kernel *shp;
170
171 shp = shm_lock(sfd->ns, sfd->id);
172 BUG_ON(IS_ERR(shp));
173 shp->shm_atim = get_seconds();
174 shp->shm_lprid = task_tgid_vnr(current);
175 shp->shm_nattch++;
176 shm_unlock(shp);
177}
178
179
180
181
182
183
184
185
186
187
188static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
189{
190 ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
191 shm_rmid(ns, shp);
192 shm_unlock(shp);
193 if (!is_file_hugepages(shp->shm_file))
194 shmem_lock(shp->shm_file, 0, shp->mlock_user);
195 else if (shp->mlock_user)
196 user_shm_unlock(file_inode(shp->shm_file)->i_size,
197 shp->mlock_user);
198 fput (shp->shm_file);
199 security_shm_free(shp);
200 ipc_rcu_putref(shp);
201}
202
203
204
205
206
207
208
209
210
211
212
213static bool shm_may_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
214{
215 return (shp->shm_nattch == 0) &&
216 (ns->shm_rmid_forced ||
217 (shp->shm_perm.mode & SHM_DEST));
218}
219
220
221
222
223
224
225
226static void shm_close(struct vm_area_struct *vma)
227{
228 struct file * file = vma->vm_file;
229 struct shm_file_data *sfd = shm_file_data(file);
230 struct shmid_kernel *shp;
231 struct ipc_namespace *ns = sfd->ns;
232
233 down_write(&shm_ids(ns).rw_mutex);
234
235 shp = shm_lock(ns, sfd->id);
236 BUG_ON(IS_ERR(shp));
237 shp->shm_lprid = task_tgid_vnr(current);
238 shp->shm_dtim = get_seconds();
239 shp->shm_nattch--;
240 if (shm_may_destroy(ns, shp))
241 shm_destroy(ns, shp);
242 else
243 shm_unlock(shp);
244 up_write(&shm_ids(ns).rw_mutex);
245}
246
247
248static int shm_try_destroy_current(int id, void *p, void *data)
249{
250 struct ipc_namespace *ns = data;
251 struct kern_ipc_perm *ipcp = p;
252 struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm);
253
254 if (shp->shm_creator != current)
255 return 0;
256
257
258
259
260
261
262 shp->shm_creator = NULL;
263
264
265
266
267
268 if (!ns->shm_rmid_forced)
269 return 0;
270
271 if (shm_may_destroy(ns, shp)) {
272 shm_lock_by_ptr(shp);
273 shm_destroy(ns, shp);
274 }
275 return 0;
276}
277
278
279static int shm_try_destroy_orphaned(int id, void *p, void *data)
280{
281 struct ipc_namespace *ns = data;
282 struct kern_ipc_perm *ipcp = p;
283 struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm);
284
285
286
287
288
289
290
291 if (shp->shm_creator != NULL)
292 return 0;
293
294 if (shm_may_destroy(ns, shp)) {
295 shm_lock_by_ptr(shp);
296 shm_destroy(ns, shp);
297 }
298 return 0;
299}
300
301void shm_destroy_orphaned(struct ipc_namespace *ns)
302{
303 down_write(&shm_ids(ns).rw_mutex);
304 if (shm_ids(ns).in_use)
305 idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_orphaned, ns);
306 up_write(&shm_ids(ns).rw_mutex);
307}
308
309
310void exit_shm(struct task_struct *task)
311{
312 struct ipc_namespace *ns = task->nsproxy->ipc_ns;
313
314 if (shm_ids(ns).in_use == 0)
315 return;
316
317
318 down_write(&shm_ids(ns).rw_mutex);
319 if (shm_ids(ns).in_use)
320 idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_current, ns);
321 up_write(&shm_ids(ns).rw_mutex);
322}
323
324static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
325{
326 struct file *file = vma->vm_file;
327 struct shm_file_data *sfd = shm_file_data(file);
328
329 return sfd->vm_ops->fault(vma, vmf);
330}
331
332#ifdef CONFIG_NUMA
333static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
334{
335 struct file *file = vma->vm_file;
336 struct shm_file_data *sfd = shm_file_data(file);
337 int err = 0;
338 if (sfd->vm_ops->set_policy)
339 err = sfd->vm_ops->set_policy(vma, new);
340 return err;
341}
342
343static struct mempolicy *shm_get_policy(struct vm_area_struct *vma,
344 unsigned long addr)
345{
346 struct file *file = vma->vm_file;
347 struct shm_file_data *sfd = shm_file_data(file);
348 struct mempolicy *pol = NULL;
349
350 if (sfd->vm_ops->get_policy)
351 pol = sfd->vm_ops->get_policy(vma, addr);
352 else if (vma->vm_policy)
353 pol = vma->vm_policy;
354
355 return pol;
356}
357#endif
358
359static int shm_mmap(struct file * file, struct vm_area_struct * vma)
360{
361 struct shm_file_data *sfd = shm_file_data(file);
362 int ret;
363
364 ret = sfd->file->f_op->mmap(sfd->file, vma);
365 if (ret != 0)
366 return ret;
367 sfd->vm_ops = vma->vm_ops;
368#ifdef CONFIG_MMU
369 BUG_ON(!sfd->vm_ops->fault);
370#endif
371 vma->vm_ops = &shm_vm_ops;
372 shm_open(vma);
373
374 return ret;
375}
376
377static int shm_release(struct inode *ino, struct file *file)
378{
379 struct shm_file_data *sfd = shm_file_data(file);
380
381 put_ipc_ns(sfd->ns);
382 shm_file_data(file) = NULL;
383 kfree(sfd);
384 return 0;
385}
386
387static int shm_fsync(struct file *file, loff_t start, loff_t end, int datasync)
388{
389 struct shm_file_data *sfd = shm_file_data(file);
390
391 if (!sfd->file->f_op->fsync)
392 return -EINVAL;
393 return sfd->file->f_op->fsync(sfd->file, start, end, datasync);
394}
395
396static long shm_fallocate(struct file *file, int mode, loff_t offset,
397 loff_t len)
398{
399 struct shm_file_data *sfd = shm_file_data(file);
400
401 if (!sfd->file->f_op->fallocate)
402 return -EOPNOTSUPP;
403 return sfd->file->f_op->fallocate(file, mode, offset, len);
404}
405
406static unsigned long shm_get_unmapped_area(struct file *file,
407 unsigned long addr, unsigned long len, unsigned long pgoff,
408 unsigned long flags)
409{
410 struct shm_file_data *sfd = shm_file_data(file);
411 return sfd->file->f_op->get_unmapped_area(sfd->file, addr, len,
412 pgoff, flags);
413}
414
415static const struct file_operations shm_file_operations = {
416 .mmap = shm_mmap,
417 .fsync = shm_fsync,
418 .release = shm_release,
419#ifndef CONFIG_MMU
420 .get_unmapped_area = shm_get_unmapped_area,
421#endif
422 .llseek = noop_llseek,
423 .fallocate = shm_fallocate,
424};
425
426static const struct file_operations shm_file_operations_huge = {
427 .mmap = shm_mmap,
428 .fsync = shm_fsync,
429 .release = shm_release,
430 .get_unmapped_area = shm_get_unmapped_area,
431 .llseek = noop_llseek,
432 .fallocate = shm_fallocate,
433};
434
435int is_file_shm_hugepages(struct file *file)
436{
437 return file->f_op == &shm_file_operations_huge;
438}
439
440static const struct vm_operations_struct shm_vm_ops = {
441 .open = shm_open,
442 .close = shm_close,
443 .fault = shm_fault,
444#if defined(CONFIG_NUMA)
445 .set_policy = shm_set_policy,
446 .get_policy = shm_get_policy,
447#endif
448};
449
450
451
452
453
454
455
456
457
458static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
459{
460 key_t key = params->key;
461 int shmflg = params->flg;
462 size_t size = params->u.size;
463 int error;
464 struct shmid_kernel *shp;
465 size_t numpages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
466 struct file * file;
467 char name[13];
468 int id;
469 vm_flags_t acctflag = 0;
470
471 if (size < SHMMIN || size > ns->shm_ctlmax)
472 return -EINVAL;
473
474 if (ns->shm_tot + numpages > ns->shm_ctlall)
475 return -ENOSPC;
476
477 shp = ipc_rcu_alloc(sizeof(*shp));
478 if (!shp)
479 return -ENOMEM;
480
481 shp->shm_perm.key = key;
482 shp->shm_perm.mode = (shmflg & S_IRWXUGO);
483 shp->mlock_user = NULL;
484
485 shp->shm_perm.security = NULL;
486 error = security_shm_alloc(shp);
487 if (error) {
488 ipc_rcu_putref(shp);
489 return error;
490 }
491
492 sprintf (name, "SYSV%08x", key);
493 if (shmflg & SHM_HUGETLB) {
494 struct hstate *hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT)
495 & SHM_HUGE_MASK);
496 size_t hugesize;
497
498 if (!hs) {
499 error = -EINVAL;
500 goto no_file;
501 }
502 hugesize = ALIGN(size, huge_page_size(hs));
503
504
505 if (shmflg & SHM_NORESERVE)
506 acctflag = VM_NORESERVE;
507 file = hugetlb_file_setup(name, hugesize, acctflag,
508 &shp->mlock_user, HUGETLB_SHMFS_INODE,
509 (shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK);
510 } else {
511
512
513
514
515 if ((shmflg & SHM_NORESERVE) &&
516 sysctl_overcommit_memory != OVERCOMMIT_NEVER)
517 acctflag = VM_NORESERVE;
518 file = shmem_file_setup(name, size, acctflag);
519 }
520 error = PTR_ERR(file);
521 if (IS_ERR(file))
522 goto no_file;
523
524 id = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni);
525 if (id < 0) {
526 error = id;
527 goto no_id;
528 }
529
530 shp->shm_cprid = task_tgid_vnr(current);
531 shp->shm_lprid = 0;
532 shp->shm_atim = shp->shm_dtim = 0;
533 shp->shm_ctim = get_seconds();
534 shp->shm_segsz = size;
535 shp->shm_nattch = 0;
536 shp->shm_file = file;
537 shp->shm_creator = current;
538
539
540
541
542 file_inode(file)->i_ino = shp->shm_perm.id;
543
544 ns->shm_tot += numpages;
545 error = shp->shm_perm.id;
546 shm_unlock(shp);
547 return error;
548
549no_id:
550 if (is_file_hugepages(file) && shp->mlock_user)
551 user_shm_unlock(size, shp->mlock_user);
552 fput(file);
553no_file:
554 security_shm_free(shp);
555 ipc_rcu_putref(shp);
556 return error;
557}
558
559
560
561
562static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
563{
564 struct shmid_kernel *shp;
565
566 shp = container_of(ipcp, struct shmid_kernel, shm_perm);
567 return security_shm_associate(shp, shmflg);
568}
569
570
571
572
573static inline int shm_more_checks(struct kern_ipc_perm *ipcp,
574 struct ipc_params *params)
575{
576 struct shmid_kernel *shp;
577
578 shp = container_of(ipcp, struct shmid_kernel, shm_perm);
579 if (shp->shm_segsz < params->u.size)
580 return -EINVAL;
581
582 return 0;
583}
584
585SYSCALL_DEFINE3(shmget, key_t, key, size_t, size, int, shmflg)
586{
587 struct ipc_namespace *ns;
588 struct ipc_ops shm_ops;
589 struct ipc_params shm_params;
590
591 ns = current->nsproxy->ipc_ns;
592
593 shm_ops.getnew = newseg;
594 shm_ops.associate = shm_security;
595 shm_ops.more_checks = shm_more_checks;
596
597 shm_params.key = key;
598 shm_params.flg = shmflg;
599 shm_params.u.size = size;
600
601 return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params);
602}
603
604static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version)
605{
606 switch(version) {
607 case IPC_64:
608 return copy_to_user(buf, in, sizeof(*in));
609 case IPC_OLD:
610 {
611 struct shmid_ds out;
612
613 memset(&out, 0, sizeof(out));
614 ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm);
615 out.shm_segsz = in->shm_segsz;
616 out.shm_atime = in->shm_atime;
617 out.shm_dtime = in->shm_dtime;
618 out.shm_ctime = in->shm_ctime;
619 out.shm_cpid = in->shm_cpid;
620 out.shm_lpid = in->shm_lpid;
621 out.shm_nattch = in->shm_nattch;
622
623 return copy_to_user(buf, &out, sizeof(out));
624 }
625 default:
626 return -EINVAL;
627 }
628}
629
630static inline unsigned long
631copy_shmid_from_user(struct shmid64_ds *out, void __user *buf, int version)
632{
633 switch(version) {
634 case IPC_64:
635 if (copy_from_user(out, buf, sizeof(*out)))
636 return -EFAULT;
637 return 0;
638 case IPC_OLD:
639 {
640 struct shmid_ds tbuf_old;
641
642 if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
643 return -EFAULT;
644
645 out->shm_perm.uid = tbuf_old.shm_perm.uid;
646 out->shm_perm.gid = tbuf_old.shm_perm.gid;
647 out->shm_perm.mode = tbuf_old.shm_perm.mode;
648
649 return 0;
650 }
651 default:
652 return -EINVAL;
653 }
654}
655
656static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminfo64 *in, int version)
657{
658 switch(version) {
659 case IPC_64:
660 return copy_to_user(buf, in, sizeof(*in));
661 case IPC_OLD:
662 {
663 struct shminfo out;
664
665 if(in->shmmax > INT_MAX)
666 out.shmmax = INT_MAX;
667 else
668 out.shmmax = (int)in->shmmax;
669
670 out.shmmin = in->shmmin;
671 out.shmmni = in->shmmni;
672 out.shmseg = in->shmseg;
673 out.shmall = in->shmall;
674
675 return copy_to_user(buf, &out, sizeof(out));
676 }
677 default:
678 return -EINVAL;
679 }
680}
681
682
683
684
685
686static void shm_add_rss_swap(struct shmid_kernel *shp,
687 unsigned long *rss_add, unsigned long *swp_add)
688{
689 struct inode *inode;
690
691 inode = file_inode(shp->shm_file);
692
693 if (is_file_hugepages(shp->shm_file)) {
694 struct address_space *mapping = inode->i_mapping;
695 struct hstate *h = hstate_file(shp->shm_file);
696 *rss_add += pages_per_huge_page(h) * mapping->nrpages;
697 } else {
698#ifdef CONFIG_SHMEM
699 struct shmem_inode_info *info = SHMEM_I(inode);
700 spin_lock(&info->lock);
701 *rss_add += inode->i_mapping->nrpages;
702 *swp_add += info->swapped;
703 spin_unlock(&info->lock);
704#else
705 *rss_add += inode->i_mapping->nrpages;
706#endif
707 }
708}
709
710
711
712
713static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
714 unsigned long *swp)
715{
716 int next_id;
717 int total, in_use;
718
719 *rss = 0;
720 *swp = 0;
721
722 in_use = shm_ids(ns).in_use;
723
724 for (total = 0, next_id = 0; total < in_use; next_id++) {
725 struct kern_ipc_perm *ipc;
726 struct shmid_kernel *shp;
727
728 ipc = idr_find(&shm_ids(ns).ipcs_idr, next_id);
729 if (ipc == NULL)
730 continue;
731 shp = container_of(ipc, struct shmid_kernel, shm_perm);
732
733 shm_add_rss_swap(shp, rss, swp);
734
735 total++;
736 }
737}
738
739
740
741
742
743
744static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
745 struct shmid_ds __user *buf, int version)
746{
747 struct kern_ipc_perm *ipcp;
748 struct shmid64_ds shmid64;
749 struct shmid_kernel *shp;
750 int err;
751
752 if (cmd == IPC_SET) {
753 if (copy_shmid_from_user(&shmid64, buf, version))
754 return -EFAULT;
755 }
756
757 ipcp = ipcctl_pre_down(ns, &shm_ids(ns), shmid, cmd,
758 &shmid64.shm_perm, 0);
759 if (IS_ERR(ipcp))
760 return PTR_ERR(ipcp);
761
762 shp = container_of(ipcp, struct shmid_kernel, shm_perm);
763
764 err = security_shm_shmctl(shp, cmd);
765 if (err)
766 goto out_unlock;
767 switch (cmd) {
768 case IPC_RMID:
769 do_shm_rmid(ns, ipcp);
770 goto out_up;
771 case IPC_SET:
772 err = ipc_update_perm(&shmid64.shm_perm, ipcp);
773 if (err)
774 goto out_unlock;
775 shp->shm_ctim = get_seconds();
776 break;
777 default:
778 err = -EINVAL;
779 }
780out_unlock:
781 shm_unlock(shp);
782out_up:
783 up_write(&shm_ids(ns).rw_mutex);
784 return err;
785}
786
787SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
788{
789 struct shmid_kernel *shp;
790 int err, version;
791 struct ipc_namespace *ns;
792
793 if (cmd < 0 || shmid < 0) {
794 err = -EINVAL;
795 goto out;
796 }
797
798 version = ipc_parse_version(&cmd);
799 ns = current->nsproxy->ipc_ns;
800
801 switch (cmd) {
802 case IPC_INFO:
803 {
804 struct shminfo64 shminfo;
805
806 err = security_shm_shmctl(NULL, cmd);
807 if (err)
808 return err;
809
810 memset(&shminfo, 0, sizeof(shminfo));
811 shminfo.shmmni = shminfo.shmseg = ns->shm_ctlmni;
812 shminfo.shmmax = ns->shm_ctlmax;
813 shminfo.shmall = ns->shm_ctlall;
814
815 shminfo.shmmin = SHMMIN;
816 if(copy_shminfo_to_user (buf, &shminfo, version))
817 return -EFAULT;
818
819 down_read(&shm_ids(ns).rw_mutex);
820 err = ipc_get_maxid(&shm_ids(ns));
821 up_read(&shm_ids(ns).rw_mutex);
822
823 if(err<0)
824 err = 0;
825 goto out;
826 }
827 case SHM_INFO:
828 {
829 struct shm_info shm_info;
830
831 err = security_shm_shmctl(NULL, cmd);
832 if (err)
833 return err;
834
835 memset(&shm_info, 0, sizeof(shm_info));
836 down_read(&shm_ids(ns).rw_mutex);
837 shm_info.used_ids = shm_ids(ns).in_use;
838 shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp);
839 shm_info.shm_tot = ns->shm_tot;
840 shm_info.swap_attempts = 0;
841 shm_info.swap_successes = 0;
842 err = ipc_get_maxid(&shm_ids(ns));
843 up_read(&shm_ids(ns).rw_mutex);
844 if (copy_to_user(buf, &shm_info, sizeof(shm_info))) {
845 err = -EFAULT;
846 goto out;
847 }
848
849 err = err < 0 ? 0 : err;
850 goto out;
851 }
852 case SHM_STAT:
853 case IPC_STAT:
854 {
855 struct shmid64_ds tbuf;
856 int result;
857
858 if (cmd == SHM_STAT) {
859 shp = shm_lock(ns, shmid);
860 if (IS_ERR(shp)) {
861 err = PTR_ERR(shp);
862 goto out;
863 }
864 result = shp->shm_perm.id;
865 } else {
866 shp = shm_lock_check(ns, shmid);
867 if (IS_ERR(shp)) {
868 err = PTR_ERR(shp);
869 goto out;
870 }
871 result = 0;
872 }
873 err = -EACCES;
874 if (ipcperms(ns, &shp->shm_perm, S_IRUGO))
875 goto out_unlock;
876 err = security_shm_shmctl(shp, cmd);
877 if (err)
878 goto out_unlock;
879 memset(&tbuf, 0, sizeof(tbuf));
880 kernel_to_ipc64_perm(&shp->shm_perm, &tbuf.shm_perm);
881 tbuf.shm_segsz = shp->shm_segsz;
882 tbuf.shm_atime = shp->shm_atim;
883 tbuf.shm_dtime = shp->shm_dtim;
884 tbuf.shm_ctime = shp->shm_ctim;
885 tbuf.shm_cpid = shp->shm_cprid;
886 tbuf.shm_lpid = shp->shm_lprid;
887 tbuf.shm_nattch = shp->shm_nattch;
888 shm_unlock(shp);
889 if(copy_shmid_to_user (buf, &tbuf, version))
890 err = -EFAULT;
891 else
892 err = result;
893 goto out;
894 }
895 case SHM_LOCK:
896 case SHM_UNLOCK:
897 {
898 struct file *shm_file;
899
900 shp = shm_lock_check(ns, shmid);
901 if (IS_ERR(shp)) {
902 err = PTR_ERR(shp);
903 goto out;
904 }
905
906 audit_ipc_obj(&(shp->shm_perm));
907
908 if (!ns_capable(ns->user_ns, CAP_IPC_LOCK)) {
909 kuid_t euid = current_euid();
910 err = -EPERM;
911 if (!uid_eq(euid, shp->shm_perm.uid) &&
912 !uid_eq(euid, shp->shm_perm.cuid))
913 goto out_unlock;
914 if (cmd == SHM_LOCK && !rlimit(RLIMIT_MEMLOCK))
915 goto out_unlock;
916 }
917
918 err = security_shm_shmctl(shp, cmd);
919 if (err)
920 goto out_unlock;
921
922 shm_file = shp->shm_file;
923 if (is_file_hugepages(shm_file))
924 goto out_unlock;
925
926 if (cmd == SHM_LOCK) {
927 struct user_struct *user = current_user();
928 err = shmem_lock(shm_file, 1, user);
929 if (!err && !(shp->shm_perm.mode & SHM_LOCKED)) {
930 shp->shm_perm.mode |= SHM_LOCKED;
931 shp->mlock_user = user;
932 }
933 goto out_unlock;
934 }
935
936
937 if (!(shp->shm_perm.mode & SHM_LOCKED))
938 goto out_unlock;
939 shmem_lock(shm_file, 0, shp->mlock_user);
940 shp->shm_perm.mode &= ~SHM_LOCKED;
941 shp->mlock_user = NULL;
942 get_file(shm_file);
943 shm_unlock(shp);
944 shmem_unlock_mapping(shm_file->f_mapping);
945 fput(shm_file);
946 goto out;
947 }
948 case IPC_RMID:
949 case IPC_SET:
950 err = shmctl_down(ns, shmid, cmd, buf, version);
951 return err;
952 default:
953 return -EINVAL;
954 }
955
956out_unlock:
957 shm_unlock(shp);
958out:
959 return err;
960}
961
962
963
964
965
966
967
968
969long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr,
970 unsigned long shmlba)
971{
972 struct shmid_kernel *shp;
973 unsigned long addr;
974 unsigned long size;
975 struct file * file;
976 int err;
977 unsigned long flags;
978 unsigned long prot;
979 int acc_mode;
980 struct ipc_namespace *ns;
981 struct shm_file_data *sfd;
982 struct path path;
983 fmode_t f_mode;
984 unsigned long populate = 0;
985
986 err = -EINVAL;
987 if (shmid < 0)
988 goto out;
989 else if ((addr = (ulong)shmaddr)) {
990 if (addr & (shmlba - 1)) {
991 if (shmflg & SHM_RND)
992 addr &= ~(shmlba - 1);
993 else
994#ifndef __ARCH_FORCE_SHMLBA
995 if (addr & ~PAGE_MASK)
996#endif
997 goto out;
998 }
999 flags = MAP_SHARED | MAP_FIXED;
1000 } else {
1001 if ((shmflg & SHM_REMAP))
1002 goto out;
1003
1004 flags = MAP_SHARED;
1005 }
1006
1007 if (shmflg & SHM_RDONLY) {
1008 prot = PROT_READ;
1009 acc_mode = S_IRUGO;
1010 f_mode = FMODE_READ;
1011 } else {
1012 prot = PROT_READ | PROT_WRITE;
1013 acc_mode = S_IRUGO | S_IWUGO;
1014 f_mode = FMODE_READ | FMODE_WRITE;
1015 }
1016 if (shmflg & SHM_EXEC) {
1017 prot |= PROT_EXEC;
1018 acc_mode |= S_IXUGO;
1019 }
1020
1021
1022
1023
1024
1025 ns = current->nsproxy->ipc_ns;
1026 shp = shm_lock_check(ns, shmid);
1027 if (IS_ERR(shp)) {
1028 err = PTR_ERR(shp);
1029 goto out;
1030 }
1031
1032 err = -EACCES;
1033 if (ipcperms(ns, &shp->shm_perm, acc_mode))
1034 goto out_unlock;
1035
1036 err = security_shm_shmat(shp, shmaddr, shmflg);
1037 if (err)
1038 goto out_unlock;
1039
1040 path = shp->shm_file->f_path;
1041 path_get(&path);
1042 shp->shm_nattch++;
1043 size = i_size_read(path.dentry->d_inode);
1044 shm_unlock(shp);
1045
1046 err = -ENOMEM;
1047 sfd = kzalloc(sizeof(*sfd), GFP_KERNEL);
1048 if (!sfd)
1049 goto out_put_dentry;
1050
1051 file = alloc_file(&path, f_mode,
1052 is_file_hugepages(shp->shm_file) ?
1053 &shm_file_operations_huge :
1054 &shm_file_operations);
1055 err = PTR_ERR(file);
1056 if (IS_ERR(file))
1057 goto out_free;
1058
1059 file->private_data = sfd;
1060 file->f_mapping = shp->shm_file->f_mapping;
1061 sfd->id = shp->shm_perm.id;
1062 sfd->ns = get_ipc_ns(ns);
1063 sfd->file = shp->shm_file;
1064 sfd->vm_ops = NULL;
1065
1066 err = security_mmap_file(file, prot, flags);
1067 if (err)
1068 goto out_fput;
1069
1070 down_write(¤t->mm->mmap_sem);
1071 if (addr && !(shmflg & SHM_REMAP)) {
1072 err = -EINVAL;
1073 if (find_vma_intersection(current->mm, addr, addr + size))
1074 goto invalid;
1075
1076
1077
1078
1079 if (addr < current->mm->start_stack &&
1080 addr > current->mm->start_stack - size - PAGE_SIZE * 5)
1081 goto invalid;
1082 }
1083
1084 addr = do_mmap_pgoff(file, addr, size, prot, flags, 0, &populate);
1085 *raddr = addr;
1086 err = 0;
1087 if (IS_ERR_VALUE(addr))
1088 err = (long)addr;
1089invalid:
1090 up_write(¤t->mm->mmap_sem);
1091 if (populate)
1092 mm_populate(addr, populate);
1093
1094out_fput:
1095 fput(file);
1096
1097out_nattch:
1098 down_write(&shm_ids(ns).rw_mutex);
1099 shp = shm_lock(ns, shmid);
1100 BUG_ON(IS_ERR(shp));
1101 shp->shm_nattch--;
1102 if (shm_may_destroy(ns, shp))
1103 shm_destroy(ns, shp);
1104 else
1105 shm_unlock(shp);
1106 up_write(&shm_ids(ns).rw_mutex);
1107
1108out:
1109 return err;
1110
1111out_unlock:
1112 shm_unlock(shp);
1113 goto out;
1114
1115out_free:
1116 kfree(sfd);
1117out_put_dentry:
1118 path_put(&path);
1119 goto out_nattch;
1120}
1121
1122SYSCALL_DEFINE3(shmat, int, shmid, char __user *, shmaddr, int, shmflg)
1123{
1124 unsigned long ret;
1125 long err;
1126
1127 err = do_shmat(shmid, shmaddr, shmflg, &ret, SHMLBA);
1128 if (err)
1129 return err;
1130 force_successful_syscall_return();
1131 return (long)ret;
1132}
1133
1134
1135
1136
1137
1138SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
1139{
1140 struct mm_struct *mm = current->mm;
1141 struct vm_area_struct *vma;
1142 unsigned long addr = (unsigned long)shmaddr;
1143 int retval = -EINVAL;
1144#ifdef CONFIG_MMU
1145 loff_t size = 0;
1146 struct vm_area_struct *next;
1147#endif
1148
1149 if (addr & ~PAGE_MASK)
1150 return retval;
1151
1152 down_write(&mm->mmap_sem);
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174 vma = find_vma(mm, addr);
1175
1176#ifdef CONFIG_MMU
1177 while (vma) {
1178 next = vma->vm_next;
1179
1180
1181
1182
1183
1184
1185 if ((vma->vm_ops == &shm_vm_ops) &&
1186 (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) {
1187
1188
1189 size = file_inode(vma->vm_file)->i_size;
1190 do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
1191
1192
1193
1194
1195
1196
1197 retval = 0;
1198 vma = next;
1199 break;
1200 }
1201 vma = next;
1202 }
1203
1204
1205
1206
1207
1208
1209 size = PAGE_ALIGN(size);
1210 while (vma && (loff_t)(vma->vm_end - addr) <= size) {
1211 next = vma->vm_next;
1212
1213
1214 if ((vma->vm_ops == &shm_vm_ops) &&
1215 (vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff)
1216
1217 do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
1218 vma = next;
1219 }
1220
1221#else
1222
1223
1224 retval = -EINVAL;
1225 if (vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) {
1226 do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
1227 retval = 0;
1228 }
1229
1230#endif
1231
1232 up_write(&mm->mmap_sem);
1233 return retval;
1234}
1235
1236#ifdef CONFIG_PROC_FS
1237static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
1238{
1239 struct user_namespace *user_ns = seq_user_ns(s);
1240 struct shmid_kernel *shp = it;
1241 unsigned long rss = 0, swp = 0;
1242
1243 shm_add_rss_swap(shp, &rss, &swp);
1244
1245#if BITS_PER_LONG <= 32
1246#define SIZE_SPEC "%10lu"
1247#else
1248#define SIZE_SPEC "%21lu"
1249#endif
1250
1251 return seq_printf(s,
1252 "%10d %10d %4o " SIZE_SPEC " %5u %5u "
1253 "%5lu %5u %5u %5u %5u %10lu %10lu %10lu "
1254 SIZE_SPEC " " SIZE_SPEC "\n",
1255 shp->shm_perm.key,
1256 shp->shm_perm.id,
1257 shp->shm_perm.mode,
1258 shp->shm_segsz,
1259 shp->shm_cprid,
1260 shp->shm_lprid,
1261 shp->shm_nattch,
1262 from_kuid_munged(user_ns, shp->shm_perm.uid),
1263 from_kgid_munged(user_ns, shp->shm_perm.gid),
1264 from_kuid_munged(user_ns, shp->shm_perm.cuid),
1265 from_kgid_munged(user_ns, shp->shm_perm.cgid),
1266 shp->shm_atim,
1267 shp->shm_dtim,
1268 shp->shm_ctim,
1269 rss * PAGE_SIZE,
1270 swp * PAGE_SIZE);
1271}
1272#endif
1273