1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org> 4 * Copyright (C) 2019 Samsung Electronics Co., Ltd. 5 */ 6 7 #include <linux/fs.h> 8 #include <linux/filelock.h> 9 #include <linux/slab.h> 10 #include <linux/vmalloc.h> 11 12 #include "glob.h" 13 #include "vfs_cache.h" 14 #include "oplock.h" 15 #include "vfs.h" 16 #include "connection.h" 17 #include "mgmt/tree_connect.h" 18 #include "mgmt/user_session.h" 19 #include "smb_common.h" 20 21 #define S_DEL_PENDING 1 22 #define S_DEL_ON_CLS 2 23 #define S_DEL_ON_CLS_STREAM 8 24 25 static unsigned int inode_hash_mask __read_mostly; 26 static unsigned int inode_hash_shift __read_mostly; 27 static struct hlist_head *inode_hashtable __read_mostly; 28 static DEFINE_RWLOCK(inode_hash_lock); 29 30 static struct ksmbd_file_table global_ft; 31 static atomic_long_t fd_limit; 32 static struct kmem_cache *filp_cache; 33 34 void ksmbd_set_fd_limit(unsigned long limit) 35 { 36 limit = min(limit, get_max_files()); 37 atomic_long_set(&fd_limit, limit); 38 } 39 40 static bool fd_limit_depleted(void) 41 { 42 long v = atomic_long_dec_return(&fd_limit); 43 44 if (v >= 0) 45 return false; 46 atomic_long_inc(&fd_limit); 47 return true; 48 } 49 50 static void fd_limit_close(void) 51 { 52 atomic_long_inc(&fd_limit); 53 } 54 55 /* 56 * INODE hash 57 */ 58 59 static unsigned long inode_hash(struct super_block *sb, unsigned long hashval) 60 { 61 unsigned long tmp; 62 63 tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) / 64 L1_CACHE_BYTES; 65 tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> inode_hash_shift); 66 return tmp & inode_hash_mask; 67 } 68 69 static struct ksmbd_inode *__ksmbd_inode_lookup(struct inode *inode) 70 { 71 struct hlist_head *head = inode_hashtable + 72 inode_hash(inode->i_sb, inode->i_ino); 73 struct ksmbd_inode *ci = NULL, *ret_ci = NULL; 74 75 hlist_for_each_entry(ci, head, m_hash) { 76 if (ci->m_inode == inode) { 77 if (atomic_inc_not_zero(&ci->m_count)) 78 ret_ci = ci; 79 break; 80 } 81 } 82 return ret_ci; 83 } 84 85 static struct ksmbd_inode *ksmbd_inode_lookup(struct ksmbd_file *fp) 86 { 87 return __ksmbd_inode_lookup(file_inode(fp->filp)); 88 } 89 90 static struct ksmbd_inode *ksmbd_inode_lookup_by_vfsinode(struct inode *inode) 91 { 92 struct ksmbd_inode *ci; 93 94 read_lock(&inode_hash_lock); 95 ci = __ksmbd_inode_lookup(inode); 96 read_unlock(&inode_hash_lock); 97 return ci; 98 } 99 100 int ksmbd_query_inode_status(struct inode *inode) 101 { 102 struct ksmbd_inode *ci; 103 int ret = KSMBD_INODE_STATUS_UNKNOWN; 104 105 read_lock(&inode_hash_lock); 106 ci = __ksmbd_inode_lookup(inode); 107 if (ci) { 108 ret = KSMBD_INODE_STATUS_OK; 109 if (ci->m_flags & S_DEL_PENDING) 110 ret = KSMBD_INODE_STATUS_PENDING_DELETE; 111 atomic_dec(&ci->m_count); 112 } 113 read_unlock(&inode_hash_lock); 114 return ret; 115 } 116 117 bool ksmbd_inode_pending_delete(struct ksmbd_file *fp) 118 { 119 return (fp->f_ci->m_flags & S_DEL_PENDING); 120 } 121 122 void ksmbd_set_inode_pending_delete(struct ksmbd_file *fp) 123 { 124 fp->f_ci->m_flags |= S_DEL_PENDING; 125 } 126 127 void ksmbd_clear_inode_pending_delete(struct ksmbd_file *fp) 128 { 129 fp->f_ci->m_flags &= ~S_DEL_PENDING; 130 } 131 132 void ksmbd_fd_set_delete_on_close(struct ksmbd_file *fp, 133 int file_info) 134 { 135 if (ksmbd_stream_fd(fp)) { 136 fp->f_ci->m_flags |= S_DEL_ON_CLS_STREAM; 137 return; 138 } 139 140 fp->f_ci->m_flags |= S_DEL_ON_CLS; 141 } 142 143 static void ksmbd_inode_hash(struct ksmbd_inode *ci) 144 { 145 struct hlist_head *b = inode_hashtable + 146 inode_hash(ci->m_inode->i_sb, ci->m_inode->i_ino); 147 148 hlist_add_head(&ci->m_hash, b); 149 } 150 151 static void ksmbd_inode_unhash(struct ksmbd_inode *ci) 152 { 153 write_lock(&inode_hash_lock); 154 hlist_del_init(&ci->m_hash); 155 write_unlock(&inode_hash_lock); 156 } 157 158 static int ksmbd_inode_init(struct ksmbd_inode *ci, struct ksmbd_file *fp) 159 { 160 ci->m_inode = file_inode(fp->filp); 161 atomic_set(&ci->m_count, 1); 162 atomic_set(&ci->op_count, 0); 163 atomic_set(&ci->sop_count, 0); 164 ci->m_flags = 0; 165 ci->m_fattr = 0; 166 INIT_LIST_HEAD(&ci->m_fp_list); 167 INIT_LIST_HEAD(&ci->m_op_list); 168 rwlock_init(&ci->m_lock); 169 return 0; 170 } 171 172 static struct ksmbd_inode *ksmbd_inode_get(struct ksmbd_file *fp) 173 { 174 struct ksmbd_inode *ci, *tmpci; 175 int rc; 176 177 read_lock(&inode_hash_lock); 178 ci = ksmbd_inode_lookup(fp); 179 read_unlock(&inode_hash_lock); 180 if (ci) 181 return ci; 182 183 ci = kmalloc(sizeof(struct ksmbd_inode), GFP_KERNEL); 184 if (!ci) 185 return NULL; 186 187 rc = ksmbd_inode_init(ci, fp); 188 if (rc) { 189 pr_err("inode initialized failed\n"); 190 kfree(ci); 191 return NULL; 192 } 193 194 write_lock(&inode_hash_lock); 195 tmpci = ksmbd_inode_lookup(fp); 196 if (!tmpci) { 197 ksmbd_inode_hash(ci); 198 } else { 199 kfree(ci); 200 ci = tmpci; 201 } 202 write_unlock(&inode_hash_lock); 203 return ci; 204 } 205 206 static void ksmbd_inode_free(struct ksmbd_inode *ci) 207 { 208 ksmbd_inode_unhash(ci); 209 kfree(ci); 210 } 211 212 static void ksmbd_inode_put(struct ksmbd_inode *ci) 213 { 214 if (atomic_dec_and_test(&ci->m_count)) 215 ksmbd_inode_free(ci); 216 } 217 218 int __init ksmbd_inode_hash_init(void) 219 { 220 unsigned int loop; 221 unsigned long numentries = 16384; 222 unsigned long bucketsize = sizeof(struct hlist_head); 223 unsigned long size; 224 225 inode_hash_shift = ilog2(numentries); 226 inode_hash_mask = (1 << inode_hash_shift) - 1; 227 228 size = bucketsize << inode_hash_shift; 229 230 /* init master fp hash table */ 231 inode_hashtable = vmalloc(size); 232 if (!inode_hashtable) 233 return -ENOMEM; 234 235 for (loop = 0; loop < (1U << inode_hash_shift); loop++) 236 INIT_HLIST_HEAD(&inode_hashtable[loop]); 237 return 0; 238 } 239 240 void ksmbd_release_inode_hash(void) 241 { 242 vfree(inode_hashtable); 243 } 244 245 static void __ksmbd_inode_close(struct ksmbd_file *fp) 246 { 247 struct ksmbd_inode *ci = fp->f_ci; 248 int err; 249 struct file *filp; 250 251 filp = fp->filp; 252 if (ksmbd_stream_fd(fp) && (ci->m_flags & S_DEL_ON_CLS_STREAM)) { 253 ci->m_flags &= ~S_DEL_ON_CLS_STREAM; 254 err = ksmbd_vfs_remove_xattr(file_mnt_idmap(filp), 255 filp->f_path.dentry, 256 fp->stream.name); 257 if (err) 258 pr_err("remove xattr failed : %s\n", 259 fp->stream.name); 260 } 261 262 if (atomic_dec_and_test(&ci->m_count)) { 263 write_lock(&ci->m_lock); 264 if (ci->m_flags & (S_DEL_ON_CLS | S_DEL_PENDING)) { 265 ci->m_flags &= ~(S_DEL_ON_CLS | S_DEL_PENDING); 266 write_unlock(&ci->m_lock); 267 ksmbd_vfs_unlink(filp); 268 write_lock(&ci->m_lock); 269 } 270 write_unlock(&ci->m_lock); 271 272 ksmbd_inode_free(ci); 273 } 274 } 275 276 static void __ksmbd_remove_durable_fd(struct ksmbd_file *fp) 277 { 278 if (!has_file_id(fp->persistent_id)) 279 return; 280 281 write_lock(&global_ft.lock); 282 idr_remove(global_ft.idr, fp->persistent_id); 283 write_unlock(&global_ft.lock); 284 } 285 286 static void __ksmbd_remove_fd(struct ksmbd_file_table *ft, struct ksmbd_file *fp) 287 { 288 if (!has_file_id(fp->volatile_id)) 289 return; 290 291 write_lock(&fp->f_ci->m_lock); 292 list_del_init(&fp->node); 293 write_unlock(&fp->f_ci->m_lock); 294 295 write_lock(&ft->lock); 296 idr_remove(ft->idr, fp->volatile_id); 297 write_unlock(&ft->lock); 298 } 299 300 static void __ksmbd_close_fd(struct ksmbd_file_table *ft, struct ksmbd_file *fp) 301 { 302 struct file *filp; 303 struct ksmbd_lock *smb_lock, *tmp_lock; 304 305 fd_limit_close(); 306 __ksmbd_remove_durable_fd(fp); 307 __ksmbd_remove_fd(ft, fp); 308 309 close_id_del_oplock(fp); 310 filp = fp->filp; 311 312 __ksmbd_inode_close(fp); 313 if (!IS_ERR_OR_NULL(filp)) 314 fput(filp); 315 316 /* because the reference count of fp is 0, it is guaranteed that 317 * there are not accesses to fp->lock_list. 318 */ 319 list_for_each_entry_safe(smb_lock, tmp_lock, &fp->lock_list, flist) { 320 spin_lock(&fp->conn->llist_lock); 321 list_del(&smb_lock->clist); 322 spin_unlock(&fp->conn->llist_lock); 323 324 list_del(&smb_lock->flist); 325 locks_free_lock(smb_lock->fl); 326 kfree(smb_lock); 327 } 328 329 if (ksmbd_stream_fd(fp)) 330 kfree(fp->stream.name); 331 kmem_cache_free(filp_cache, fp); 332 } 333 334 static struct ksmbd_file *ksmbd_fp_get(struct ksmbd_file *fp) 335 { 336 if (!atomic_inc_not_zero(&fp->refcount)) 337 return NULL; 338 return fp; 339 } 340 341 static struct ksmbd_file *__ksmbd_lookup_fd(struct ksmbd_file_table *ft, 342 u64 id) 343 { 344 struct ksmbd_file *fp; 345 346 if (!has_file_id(id)) 347 return NULL; 348 349 read_lock(&ft->lock); 350 fp = idr_find(ft->idr, id); 351 if (fp) 352 fp = ksmbd_fp_get(fp); 353 read_unlock(&ft->lock); 354 return fp; 355 } 356 357 static void __put_fd_final(struct ksmbd_work *work, struct ksmbd_file *fp) 358 { 359 __ksmbd_close_fd(&work->sess->file_table, fp); 360 atomic_dec(&work->conn->stats.open_files_count); 361 } 362 363 static void set_close_state_blocked_works(struct ksmbd_file *fp) 364 { 365 struct ksmbd_work *cancel_work; 366 367 spin_lock(&fp->f_lock); 368 list_for_each_entry(cancel_work, &fp->blocked_works, 369 fp_entry) { 370 cancel_work->state = KSMBD_WORK_CLOSED; 371 cancel_work->cancel_fn(cancel_work->cancel_argv); 372 } 373 spin_unlock(&fp->f_lock); 374 } 375 376 int ksmbd_close_fd(struct ksmbd_work *work, u64 id) 377 { 378 struct ksmbd_file *fp; 379 struct ksmbd_file_table *ft; 380 381 if (!has_file_id(id)) 382 return 0; 383 384 ft = &work->sess->file_table; 385 read_lock(&ft->lock); 386 fp = idr_find(ft->idr, id); 387 if (fp) { 388 set_close_state_blocked_works(fp); 389 390 if (!atomic_dec_and_test(&fp->refcount)) 391 fp = NULL; 392 } 393 read_unlock(&ft->lock); 394 395 if (!fp) 396 return -EINVAL; 397 398 __put_fd_final(work, fp); 399 return 0; 400 } 401 402 void ksmbd_fd_put(struct ksmbd_work *work, struct ksmbd_file *fp) 403 { 404 if (!fp) 405 return; 406 407 if (!atomic_dec_and_test(&fp->refcount)) 408 return; 409 __put_fd_final(work, fp); 410 } 411 412 static bool __sanity_check(struct ksmbd_tree_connect *tcon, struct ksmbd_file *fp) 413 { 414 if (!fp) 415 return false; 416 if (fp->tcon != tcon) 417 return false; 418 return true; 419 } 420 421 struct ksmbd_file *ksmbd_lookup_foreign_fd(struct ksmbd_work *work, u64 id) 422 { 423 return __ksmbd_lookup_fd(&work->sess->file_table, id); 424 } 425 426 struct ksmbd_file *ksmbd_lookup_fd_fast(struct ksmbd_work *work, u64 id) 427 { 428 struct ksmbd_file *fp = __ksmbd_lookup_fd(&work->sess->file_table, id); 429 430 if (__sanity_check(work->tcon, fp)) 431 return fp; 432 433 ksmbd_fd_put(work, fp); 434 return NULL; 435 } 436 437 struct ksmbd_file *ksmbd_lookup_fd_slow(struct ksmbd_work *work, u64 id, 438 u64 pid) 439 { 440 struct ksmbd_file *fp; 441 442 if (!has_file_id(id)) { 443 id = work->compound_fid; 444 pid = work->compound_pfid; 445 } 446 447 fp = __ksmbd_lookup_fd(&work->sess->file_table, id); 448 if (!__sanity_check(work->tcon, fp)) { 449 ksmbd_fd_put(work, fp); 450 return NULL; 451 } 452 if (fp->persistent_id != pid) { 453 ksmbd_fd_put(work, fp); 454 return NULL; 455 } 456 return fp; 457 } 458 459 struct ksmbd_file *ksmbd_lookup_durable_fd(unsigned long long id) 460 { 461 return __ksmbd_lookup_fd(&global_ft, id); 462 } 463 464 struct ksmbd_file *ksmbd_lookup_fd_cguid(char *cguid) 465 { 466 struct ksmbd_file *fp = NULL; 467 unsigned int id; 468 469 read_lock(&global_ft.lock); 470 idr_for_each_entry(global_ft.idr, fp, id) { 471 if (!memcmp(fp->create_guid, 472 cguid, 473 SMB2_CREATE_GUID_SIZE)) { 474 fp = ksmbd_fp_get(fp); 475 break; 476 } 477 } 478 read_unlock(&global_ft.lock); 479 480 return fp; 481 } 482 483 struct ksmbd_file *ksmbd_lookup_fd_inode(struct inode *inode) 484 { 485 struct ksmbd_file *lfp; 486 struct ksmbd_inode *ci; 487 488 ci = ksmbd_inode_lookup_by_vfsinode(inode); 489 if (!ci) 490 return NULL; 491 492 read_lock(&ci->m_lock); 493 list_for_each_entry(lfp, &ci->m_fp_list, node) { 494 if (inode == file_inode(lfp->filp)) { 495 atomic_dec(&ci->m_count); 496 lfp = ksmbd_fp_get(lfp); 497 read_unlock(&ci->m_lock); 498 return lfp; 499 } 500 } 501 atomic_dec(&ci->m_count); 502 read_unlock(&ci->m_lock); 503 return NULL; 504 } 505 506 #define OPEN_ID_TYPE_VOLATILE_ID (0) 507 #define OPEN_ID_TYPE_PERSISTENT_ID (1) 508 509 static void __open_id_set(struct ksmbd_file *fp, u64 id, int type) 510 { 511 if (type == OPEN_ID_TYPE_VOLATILE_ID) 512 fp->volatile_id = id; 513 if (type == OPEN_ID_TYPE_PERSISTENT_ID) 514 fp->persistent_id = id; 515 } 516 517 static int __open_id(struct ksmbd_file_table *ft, struct ksmbd_file *fp, 518 int type) 519 { 520 u64 id = 0; 521 int ret; 522 523 if (type == OPEN_ID_TYPE_VOLATILE_ID && fd_limit_depleted()) { 524 __open_id_set(fp, KSMBD_NO_FID, type); 525 return -EMFILE; 526 } 527 528 idr_preload(GFP_KERNEL); 529 write_lock(&ft->lock); 530 ret = idr_alloc_cyclic(ft->idr, fp, 0, INT_MAX - 1, GFP_NOWAIT); 531 if (ret >= 0) { 532 id = ret; 533 ret = 0; 534 } else { 535 id = KSMBD_NO_FID; 536 fd_limit_close(); 537 } 538 539 __open_id_set(fp, id, type); 540 write_unlock(&ft->lock); 541 idr_preload_end(); 542 return ret; 543 } 544 545 unsigned int ksmbd_open_durable_fd(struct ksmbd_file *fp) 546 { 547 __open_id(&global_ft, fp, OPEN_ID_TYPE_PERSISTENT_ID); 548 return fp->persistent_id; 549 } 550 551 struct ksmbd_file *ksmbd_open_fd(struct ksmbd_work *work, struct file *filp) 552 { 553 struct ksmbd_file *fp; 554 int ret; 555 556 fp = kmem_cache_zalloc(filp_cache, GFP_KERNEL); 557 if (!fp) { 558 pr_err("Failed to allocate memory\n"); 559 return ERR_PTR(-ENOMEM); 560 } 561 562 INIT_LIST_HEAD(&fp->blocked_works); 563 INIT_LIST_HEAD(&fp->node); 564 INIT_LIST_HEAD(&fp->lock_list); 565 spin_lock_init(&fp->f_lock); 566 atomic_set(&fp->refcount, 1); 567 568 fp->filp = filp; 569 fp->conn = work->conn; 570 fp->tcon = work->tcon; 571 fp->volatile_id = KSMBD_NO_FID; 572 fp->persistent_id = KSMBD_NO_FID; 573 fp->f_ci = ksmbd_inode_get(fp); 574 575 if (!fp->f_ci) { 576 ret = -ENOMEM; 577 goto err_out; 578 } 579 580 ret = __open_id(&work->sess->file_table, fp, OPEN_ID_TYPE_VOLATILE_ID); 581 if (ret) { 582 ksmbd_inode_put(fp->f_ci); 583 goto err_out; 584 } 585 586 atomic_inc(&work->conn->stats.open_files_count); 587 return fp; 588 589 err_out: 590 kmem_cache_free(filp_cache, fp); 591 return ERR_PTR(ret); 592 } 593 594 static int 595 __close_file_table_ids(struct ksmbd_file_table *ft, 596 struct ksmbd_tree_connect *tcon, 597 bool (*skip)(struct ksmbd_tree_connect *tcon, 598 struct ksmbd_file *fp)) 599 { 600 unsigned int id; 601 struct ksmbd_file *fp; 602 int num = 0; 603 604 idr_for_each_entry(ft->idr, fp, id) { 605 if (skip(tcon, fp)) 606 continue; 607 608 set_close_state_blocked_works(fp); 609 610 if (!atomic_dec_and_test(&fp->refcount)) 611 continue; 612 __ksmbd_close_fd(ft, fp); 613 num++; 614 } 615 return num; 616 } 617 618 static bool tree_conn_fd_check(struct ksmbd_tree_connect *tcon, 619 struct ksmbd_file *fp) 620 { 621 return fp->tcon != tcon; 622 } 623 624 static bool session_fd_check(struct ksmbd_tree_connect *tcon, 625 struct ksmbd_file *fp) 626 { 627 return false; 628 } 629 630 void ksmbd_close_tree_conn_fds(struct ksmbd_work *work) 631 { 632 int num = __close_file_table_ids(&work->sess->file_table, 633 work->tcon, 634 tree_conn_fd_check); 635 636 atomic_sub(num, &work->conn->stats.open_files_count); 637 } 638 639 void ksmbd_close_session_fds(struct ksmbd_work *work) 640 { 641 int num = __close_file_table_ids(&work->sess->file_table, 642 work->tcon, 643 session_fd_check); 644 645 atomic_sub(num, &work->conn->stats.open_files_count); 646 } 647 648 int ksmbd_init_global_file_table(void) 649 { 650 return ksmbd_init_file_table(&global_ft); 651 } 652 653 void ksmbd_free_global_file_table(void) 654 { 655 struct ksmbd_file *fp = NULL; 656 unsigned int id; 657 658 idr_for_each_entry(global_ft.idr, fp, id) { 659 __ksmbd_remove_durable_fd(fp); 660 kmem_cache_free(filp_cache, fp); 661 } 662 663 ksmbd_destroy_file_table(&global_ft); 664 } 665 666 int ksmbd_init_file_table(struct ksmbd_file_table *ft) 667 { 668 ft->idr = kzalloc(sizeof(struct idr), GFP_KERNEL); 669 if (!ft->idr) 670 return -ENOMEM; 671 672 idr_init(ft->idr); 673 rwlock_init(&ft->lock); 674 return 0; 675 } 676 677 void ksmbd_destroy_file_table(struct ksmbd_file_table *ft) 678 { 679 if (!ft->idr) 680 return; 681 682 __close_file_table_ids(ft, NULL, session_fd_check); 683 idr_destroy(ft->idr); 684 kfree(ft->idr); 685 ft->idr = NULL; 686 } 687 688 int ksmbd_init_file_cache(void) 689 { 690 filp_cache = kmem_cache_create("ksmbd_file_cache", 691 sizeof(struct ksmbd_file), 0, 692 SLAB_HWCACHE_ALIGN, NULL); 693 if (!filp_cache) 694 goto out; 695 696 return 0; 697 698 out: 699 pr_err("failed to allocate file cache\n"); 700 return -ENOMEM; 701 } 702 703 void ksmbd_exit_file_cache(void) 704 { 705 kmem_cache_destroy(filp_cache); 706 } 707