1 // SPDX-License-Identifier: LGPL-2.1+ 2 /* 3 * Copyright (C) International Business Machines Corp., 2007,2008 4 * Author(s): Steve French (sfrench@us.ibm.com) 5 * Copyright (C) 2020 Samsung Electronics Co., Ltd. 6 * Author(s): Namjae Jeon <linkinjeon@kernel.org> 7 */ 8 9 #include <linux/fs.h> 10 #include <linux/slab.h> 11 #include <linux/string.h> 12 #include <linux/mnt_idmapping.h> 13 14 #include "smbacl.h" 15 #include "smb_common.h" 16 #include "server.h" 17 #include "misc.h" 18 #include "mgmt/share_config.h" 19 20 static const struct smb_sid domain = {1, 4, {0, 0, 0, 0, 0, 5}, 21 {cpu_to_le32(21), cpu_to_le32(1), cpu_to_le32(2), cpu_to_le32(3), 22 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 23 24 /* security id for everyone/world system group */ 25 static const struct smb_sid creator_owner = { 26 1, 1, {0, 0, 0, 0, 0, 3}, {0} }; 27 /* security id for everyone/world system group */ 28 static const struct smb_sid creator_group = { 29 1, 1, {0, 0, 0, 0, 0, 3}, {cpu_to_le32(1)} }; 30 31 /* security id for everyone/world system group */ 32 static const struct smb_sid sid_everyone = { 33 1, 1, {0, 0, 0, 0, 0, 1}, {0} }; 34 /* security id for Authenticated Users system group */ 35 static const struct smb_sid sid_authusers = { 36 1, 1, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(11)} }; 37 38 /* S-1-22-1 Unmapped Unix users */ 39 static const struct smb_sid sid_unix_users = {1, 1, {0, 0, 0, 0, 0, 22}, 40 {cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 41 42 /* S-1-22-2 Unmapped Unix groups */ 43 static const struct smb_sid sid_unix_groups = { 1, 1, {0, 0, 0, 0, 0, 22}, 44 {cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 45 46 /* 47 * See http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx 48 */ 49 50 /* S-1-5-88 MS NFS and Apple style UID/GID/mode */ 51 52 /* S-1-5-88-1 Unix uid */ 53 static const struct smb_sid sid_unix_NFS_users = { 1, 2, {0, 0, 0, 0, 0, 5}, 54 {cpu_to_le32(88), 55 cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 56 57 /* S-1-5-88-2 Unix gid */ 58 static const struct smb_sid sid_unix_NFS_groups = { 1, 2, {0, 0, 0, 0, 0, 5}, 59 {cpu_to_le32(88), 60 cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 61 62 /* S-1-5-88-3 Unix mode */ 63 static const struct smb_sid sid_unix_NFS_mode = { 1, 2, {0, 0, 0, 0, 0, 5}, 64 {cpu_to_le32(88), 65 cpu_to_le32(3), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }; 66 67 /* 68 * if the two SIDs (roughly equivalent to a UUID for a user or group) are 69 * the same returns zero, if they do not match returns non-zero. 70 */ 71 int compare_sids(const struct smb_sid *ctsid, const struct smb_sid *cwsid) 72 { 73 int i; 74 int num_subauth, num_sat, num_saw; 75 76 if (!ctsid || !cwsid) 77 return 1; 78 79 /* compare the revision */ 80 if (ctsid->revision != cwsid->revision) { 81 if (ctsid->revision > cwsid->revision) 82 return 1; 83 else 84 return -1; 85 } 86 87 /* compare all of the six auth values */ 88 for (i = 0; i < NUM_AUTHS; ++i) { 89 if (ctsid->authority[i] != cwsid->authority[i]) { 90 if (ctsid->authority[i] > cwsid->authority[i]) 91 return 1; 92 else 93 return -1; 94 } 95 } 96 97 /* compare all of the subauth values if any */ 98 num_sat = ctsid->num_subauth; 99 num_saw = cwsid->num_subauth; 100 num_subauth = min(num_sat, num_saw); 101 if (num_subauth) { 102 for (i = 0; i < num_subauth; ++i) { 103 if (ctsid->sub_auth[i] != cwsid->sub_auth[i]) { 104 if (le32_to_cpu(ctsid->sub_auth[i]) > 105 le32_to_cpu(cwsid->sub_auth[i])) 106 return 1; 107 else 108 return -1; 109 } 110 } 111 } 112 113 return 0; /* sids compare/match */ 114 } 115 116 static void smb_copy_sid(struct smb_sid *dst, const struct smb_sid *src) 117 { 118 int i; 119 120 dst->revision = src->revision; 121 dst->num_subauth = min_t(u8, src->num_subauth, SID_MAX_SUB_AUTHORITIES); 122 for (i = 0; i < NUM_AUTHS; ++i) 123 dst->authority[i] = src->authority[i]; 124 for (i = 0; i < dst->num_subauth; ++i) 125 dst->sub_auth[i] = src->sub_auth[i]; 126 } 127 128 /* 129 * change posix mode to reflect permissions 130 * pmode is the existing mode (we only want to overwrite part of this 131 * bits to set can be: S_IRWXU, S_IRWXG or S_IRWXO ie 00700 or 00070 or 00007 132 */ 133 static umode_t access_flags_to_mode(struct smb_fattr *fattr, __le32 ace_flags, 134 int type) 135 { 136 __u32 flags = le32_to_cpu(ace_flags); 137 umode_t mode = 0; 138 139 if (flags & GENERIC_ALL) { 140 mode = 0777; 141 ksmbd_debug(SMB, "all perms\n"); 142 return mode; 143 } 144 145 if ((flags & GENERIC_READ) || (flags & FILE_READ_RIGHTS)) 146 mode = 0444; 147 if ((flags & GENERIC_WRITE) || (flags & FILE_WRITE_RIGHTS)) { 148 mode |= 0222; 149 if (S_ISDIR(fattr->cf_mode)) 150 mode |= 0111; 151 } 152 if ((flags & GENERIC_EXECUTE) || (flags & FILE_EXEC_RIGHTS)) 153 mode |= 0111; 154 155 if (type == ACCESS_DENIED_ACE_TYPE || type == ACCESS_DENIED_OBJECT_ACE_TYPE) 156 mode = ~mode; 157 158 ksmbd_debug(SMB, "access flags 0x%x mode now %04o\n", flags, mode); 159 160 return mode; 161 } 162 163 /* 164 * Generate access flags to reflect permissions mode is the existing mode. 165 * This function is called for every ACE in the DACL whose SID matches 166 * with either owner or group or everyone. 167 */ 168 static void mode_to_access_flags(umode_t mode, umode_t bits_to_use, 169 __u32 *pace_flags) 170 { 171 /* reset access mask */ 172 *pace_flags = 0x0; 173 174 /* bits to use are either S_IRWXU or S_IRWXG or S_IRWXO */ 175 mode &= bits_to_use; 176 177 /* 178 * check for R/W/X UGO since we do not know whose flags 179 * is this but we have cleared all the bits sans RWX for 180 * either user or group or other as per bits_to_use 181 */ 182 if (mode & 0444) 183 *pace_flags |= SET_FILE_READ_RIGHTS; 184 if (mode & 0222) 185 *pace_flags |= FILE_WRITE_RIGHTS; 186 if (mode & 0111) 187 *pace_flags |= SET_FILE_EXEC_RIGHTS; 188 189 ksmbd_debug(SMB, "mode: %o, access flags now 0x%x\n", 190 mode, *pace_flags); 191 } 192 193 static __u16 fill_ace_for_sid(struct smb_ace *pntace, 194 const struct smb_sid *psid, int type, int flags, 195 umode_t mode, umode_t bits) 196 { 197 int i; 198 __u16 size = 0; 199 __u32 access_req = 0; 200 201 pntace->type = type; 202 pntace->flags = flags; 203 mode_to_access_flags(mode, bits, &access_req); 204 if (!access_req) 205 access_req = SET_MINIMUM_RIGHTS; 206 pntace->access_req = cpu_to_le32(access_req); 207 208 pntace->sid.revision = psid->revision; 209 pntace->sid.num_subauth = psid->num_subauth; 210 for (i = 0; i < NUM_AUTHS; i++) 211 pntace->sid.authority[i] = psid->authority[i]; 212 for (i = 0; i < psid->num_subauth; i++) 213 pntace->sid.sub_auth[i] = psid->sub_auth[i]; 214 215 size = 1 + 1 + 2 + 4 + 1 + 1 + 6 + (psid->num_subauth * 4); 216 pntace->size = cpu_to_le16(size); 217 218 return size; 219 } 220 221 void id_to_sid(unsigned int cid, uint sidtype, struct smb_sid *ssid) 222 { 223 switch (sidtype) { 224 case SIDOWNER: 225 smb_copy_sid(ssid, &server_conf.domain_sid); 226 break; 227 case SIDUNIX_USER: 228 smb_copy_sid(ssid, &sid_unix_users); 229 break; 230 case SIDUNIX_GROUP: 231 smb_copy_sid(ssid, &sid_unix_groups); 232 break; 233 case SIDCREATOR_OWNER: 234 smb_copy_sid(ssid, &creator_owner); 235 return; 236 case SIDCREATOR_GROUP: 237 smb_copy_sid(ssid, &creator_group); 238 return; 239 case SIDNFS_USER: 240 smb_copy_sid(ssid, &sid_unix_NFS_users); 241 break; 242 case SIDNFS_GROUP: 243 smb_copy_sid(ssid, &sid_unix_NFS_groups); 244 break; 245 case SIDNFS_MODE: 246 smb_copy_sid(ssid, &sid_unix_NFS_mode); 247 break; 248 default: 249 return; 250 } 251 252 /* RID */ 253 ssid->sub_auth[ssid->num_subauth] = cpu_to_le32(cid); 254 ssid->num_subauth++; 255 } 256 257 static int sid_to_id(struct mnt_idmap *idmap, 258 struct smb_sid *psid, uint sidtype, 259 struct smb_fattr *fattr) 260 { 261 int rc = -EINVAL; 262 263 /* 264 * If we have too many subauthorities, then something is really wrong. 265 * Just return an error. 266 */ 267 if (unlikely(psid->num_subauth > SID_MAX_SUB_AUTHORITIES)) { 268 pr_err("%s: %u subauthorities is too many!\n", 269 __func__, psid->num_subauth); 270 return -EIO; 271 } 272 273 if (psid->num_subauth == 0) { 274 pr_err("%s: zero subauthorities!\n", __func__); 275 return -EIO; 276 } 277 278 if (sidtype == SIDOWNER) { 279 kuid_t uid; 280 uid_t id; 281 282 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]); 283 uid = KUIDT_INIT(id); 284 uid = from_vfsuid(idmap, &init_user_ns, VFSUIDT_INIT(uid)); 285 if (uid_valid(uid)) { 286 fattr->cf_uid = uid; 287 rc = 0; 288 } 289 } else { 290 kgid_t gid; 291 gid_t id; 292 293 id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]); 294 gid = KGIDT_INIT(id); 295 gid = from_vfsgid(idmap, &init_user_ns, VFSGIDT_INIT(gid)); 296 if (gid_valid(gid)) { 297 fattr->cf_gid = gid; 298 rc = 0; 299 } 300 } 301 302 return rc; 303 } 304 305 void posix_state_to_acl(struct posix_acl_state *state, 306 struct posix_acl_entry *pace) 307 { 308 int i; 309 310 pace->e_tag = ACL_USER_OBJ; 311 pace->e_perm = state->owner.allow; 312 for (i = 0; i < state->users->n; i++) { 313 pace++; 314 pace->e_tag = ACL_USER; 315 pace->e_uid = state->users->aces[i].uid; 316 pace->e_perm = state->users->aces[i].perms.allow; 317 } 318 319 pace++; 320 pace->e_tag = ACL_GROUP_OBJ; 321 pace->e_perm = state->group.allow; 322 323 for (i = 0; i < state->groups->n; i++) { 324 pace++; 325 pace->e_tag = ACL_GROUP; 326 pace->e_gid = state->groups->aces[i].gid; 327 pace->e_perm = state->groups->aces[i].perms.allow; 328 } 329 330 if (state->users->n || state->groups->n) { 331 pace++; 332 pace->e_tag = ACL_MASK; 333 pace->e_perm = state->mask.allow; 334 } 335 336 pace++; 337 pace->e_tag = ACL_OTHER; 338 pace->e_perm = state->other.allow; 339 } 340 341 int init_acl_state(struct posix_acl_state *state, u16 cnt) 342 { 343 int alloc; 344 345 memset(state, 0, sizeof(struct posix_acl_state)); 346 /* 347 * In the worst case, each individual acl could be for a distinct 348 * named user or group, but we don't know which, so we allocate 349 * enough space for either: 350 */ 351 alloc = sizeof(struct posix_ace_state_array) 352 + cnt * sizeof(struct posix_user_ace_state); 353 state->users = kzalloc(alloc, KSMBD_DEFAULT_GFP); 354 if (!state->users) 355 return -ENOMEM; 356 state->groups = kzalloc(alloc, KSMBD_DEFAULT_GFP); 357 if (!state->groups) { 358 kfree(state->users); 359 return -ENOMEM; 360 } 361 return 0; 362 } 363 364 void free_acl_state(struct posix_acl_state *state) 365 { 366 kfree(state->users); 367 kfree(state->groups); 368 } 369 370 static void parse_dacl(struct mnt_idmap *idmap, 371 struct smb_acl *pdacl, char *end_of_acl, 372 struct smb_sid *pownersid, struct smb_sid *pgrpsid, 373 struct smb_fattr *fattr) 374 { 375 int i, ret; 376 u16 num_aces = 0; 377 unsigned int acl_size; 378 char *acl_base; 379 struct smb_ace **ppace; 380 struct posix_acl_entry *cf_pace, *cf_pdace; 381 struct posix_acl_state acl_state, default_acl_state; 382 umode_t mode = 0, acl_mode; 383 bool owner_found = false, group_found = false, others_found = false; 384 385 if (!pdacl) 386 return; 387 388 /* validate that we do not go past end of acl */ 389 if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) || 390 end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) { 391 pr_err("ACL too small to parse DACL\n"); 392 return; 393 } 394 395 ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n", 396 le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size), 397 le16_to_cpu(pdacl->num_aces)); 398 399 acl_base = (char *)pdacl; 400 acl_size = sizeof(struct smb_acl); 401 402 num_aces = le16_to_cpu(pdacl->num_aces); 403 if (num_aces <= 0) 404 return; 405 406 if (num_aces > (le16_to_cpu(pdacl->size) - sizeof(struct smb_acl)) / 407 (offsetof(struct smb_ace, sid) + 408 offsetof(struct smb_sid, sub_auth) + sizeof(__le16))) 409 return; 410 411 ret = init_acl_state(&acl_state, num_aces); 412 if (ret) 413 return; 414 ret = init_acl_state(&default_acl_state, num_aces); 415 if (ret) { 416 free_acl_state(&acl_state); 417 return; 418 } 419 420 ppace = kmalloc_objs(struct smb_ace *, num_aces, KSMBD_DEFAULT_GFP); 421 if (!ppace) { 422 free_acl_state(&default_acl_state); 423 free_acl_state(&acl_state); 424 return; 425 } 426 427 /* 428 * reset rwx permissions for user/group/other. 429 * Also, if num_aces is 0 i.e. DACL has no ACEs, 430 * user/group/other have no permissions 431 */ 432 for (i = 0; i < num_aces; ++i) { 433 if (end_of_acl - acl_base < acl_size) 434 break; 435 436 ppace[i] = (struct smb_ace *)(acl_base + acl_size); 437 acl_base = (char *)ppace[i]; 438 acl_size = offsetof(struct smb_ace, sid) + 439 offsetof(struct smb_sid, sub_auth); 440 441 if (end_of_acl - acl_base < acl_size || 442 ppace[i]->sid.num_subauth == 0 || 443 ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES || 444 (end_of_acl - acl_base < 445 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) || 446 (le16_to_cpu(ppace[i]->size) < 447 acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth)) 448 break; 449 450 acl_size = le16_to_cpu(ppace[i]->size); 451 ppace[i]->access_req = 452 smb_map_generic_desired_access(ppace[i]->access_req); 453 454 if (ppace[i]->sid.num_subauth >= 3 && 455 !(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) { 456 fattr->cf_mode = 457 le32_to_cpu(ppace[i]->sid.sub_auth[2]); 458 break; 459 } else if (!compare_sids(&ppace[i]->sid, pownersid)) { 460 acl_mode = access_flags_to_mode(fattr, 461 ppace[i]->access_req, 462 ppace[i]->type); 463 acl_mode &= 0700; 464 465 if (!owner_found) { 466 mode &= ~(0700); 467 mode |= acl_mode; 468 } 469 owner_found = true; 470 } else if (!compare_sids(&ppace[i]->sid, pgrpsid) || 471 ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] == 472 DOMAIN_USER_RID_LE) { 473 acl_mode = access_flags_to_mode(fattr, 474 ppace[i]->access_req, 475 ppace[i]->type); 476 acl_mode &= 0070; 477 if (!group_found) { 478 mode &= ~(0070); 479 mode |= acl_mode; 480 } 481 group_found = true; 482 } else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) { 483 acl_mode = access_flags_to_mode(fattr, 484 ppace[i]->access_req, 485 ppace[i]->type); 486 acl_mode &= 0007; 487 if (!others_found) { 488 mode &= ~(0007); 489 mode |= acl_mode; 490 } 491 others_found = true; 492 } else if (!compare_sids(&ppace[i]->sid, &creator_owner)) { 493 continue; 494 } else if (!compare_sids(&ppace[i]->sid, &creator_group)) { 495 continue; 496 } else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) { 497 continue; 498 } else { 499 struct smb_fattr temp_fattr; 500 501 acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req, 502 ppace[i]->type); 503 temp_fattr.cf_uid = INVALID_UID; 504 ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr); 505 if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) { 506 pr_err("%s: Error %d mapping Owner SID to uid\n", 507 __func__, ret); 508 continue; 509 } 510 511 acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004; 512 acl_state.users->aces[acl_state.users->n].uid = 513 temp_fattr.cf_uid; 514 acl_state.users->aces[acl_state.users->n++].perms.allow = 515 ((acl_mode & 0700) >> 6) | 0004; 516 default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004; 517 default_acl_state.users->aces[default_acl_state.users->n].uid = 518 temp_fattr.cf_uid; 519 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow = 520 ((acl_mode & 0700) >> 6) | 0004; 521 } 522 } 523 kfree(ppace); 524 525 if (owner_found) { 526 /* The owner must be set to at least read-only. */ 527 acl_state.owner.allow = ((mode & 0700) >> 6) | 0004; 528 acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid; 529 acl_state.users->aces[acl_state.users->n++].perms.allow = 530 ((mode & 0700) >> 6) | 0004; 531 default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004; 532 default_acl_state.users->aces[default_acl_state.users->n].uid = 533 fattr->cf_uid; 534 default_acl_state.users->aces[default_acl_state.users->n++].perms.allow = 535 ((mode & 0700) >> 6) | 0004; 536 } 537 538 if (group_found) { 539 acl_state.group.allow = (mode & 0070) >> 3; 540 acl_state.groups->aces[acl_state.groups->n].gid = 541 fattr->cf_gid; 542 acl_state.groups->aces[acl_state.groups->n++].perms.allow = 543 (mode & 0070) >> 3; 544 default_acl_state.group.allow = (mode & 0070) >> 3; 545 default_acl_state.groups->aces[default_acl_state.groups->n].gid = 546 fattr->cf_gid; 547 default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow = 548 (mode & 0070) >> 3; 549 } 550 551 if (others_found) { 552 fattr->cf_mode &= ~(0007); 553 fattr->cf_mode |= mode & 0007; 554 555 acl_state.other.allow = mode & 0007; 556 default_acl_state.other.allow = mode & 0007; 557 } 558 559 if (acl_state.users->n || acl_state.groups->n) { 560 acl_state.mask.allow = 0x07; 561 562 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 563 fattr->cf_acls = 564 posix_acl_alloc(acl_state.users->n + 565 acl_state.groups->n + 4, KSMBD_DEFAULT_GFP); 566 if (fattr->cf_acls) { 567 cf_pace = fattr->cf_acls->a_entries; 568 posix_state_to_acl(&acl_state, cf_pace); 569 } 570 } 571 } 572 573 if (default_acl_state.users->n || default_acl_state.groups->n) { 574 default_acl_state.mask.allow = 0x07; 575 576 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 577 fattr->cf_dacls = 578 posix_acl_alloc(default_acl_state.users->n + 579 default_acl_state.groups->n + 4, KSMBD_DEFAULT_GFP); 580 if (fattr->cf_dacls) { 581 cf_pdace = fattr->cf_dacls->a_entries; 582 posix_state_to_acl(&default_acl_state, cf_pdace); 583 } 584 } 585 } 586 free_acl_state(&acl_state); 587 free_acl_state(&default_acl_state); 588 } 589 590 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap, 591 struct smb_ace *pndace, 592 struct smb_fattr *fattr, u16 *num_aces, 593 u16 *size, u32 nt_aces_num) 594 { 595 struct posix_acl_entry *pace; 596 struct smb_sid *sid; 597 struct smb_ace *ntace; 598 int i, j; 599 u16 ace_sz; 600 601 if (!fattr->cf_acls) 602 goto posix_default_acl; 603 604 pace = fattr->cf_acls->a_entries; 605 for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) { 606 int flags = 0; 607 608 sid = kmalloc_obj(struct smb_sid, KSMBD_DEFAULT_GFP); 609 if (!sid) 610 break; 611 612 if (pace->e_tag == ACL_USER) { 613 uid_t uid; 614 unsigned int sid_type = SIDOWNER; 615 616 uid = posix_acl_uid_translate(idmap, pace); 617 if (!uid) 618 sid_type = SIDUNIX_USER; 619 id_to_sid(uid, sid_type, sid); 620 } else if (pace->e_tag == ACL_GROUP) { 621 gid_t gid; 622 623 gid = posix_acl_gid_translate(idmap, pace); 624 id_to_sid(gid, SIDUNIX_GROUP, sid); 625 } else if (pace->e_tag == ACL_OTHER && !nt_aces_num) { 626 smb_copy_sid(sid, &sid_everyone); 627 } else { 628 kfree(sid); 629 continue; 630 } 631 ntace = pndace; 632 for (j = 0; j < nt_aces_num; j++) { 633 if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] == 634 sid->sub_auth[sid->num_subauth - 1]) 635 goto pass_same_sid; 636 ntace = (struct smb_ace *)((char *)ntace + 637 le16_to_cpu(ntace->size)); 638 } 639 640 if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER) 641 flags = 0x03; 642 643 ntace = (struct smb_ace *)((char *)pndace + *size); 644 ace_sz = fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags, 645 pace->e_perm, 0777); 646 if (check_add_overflow(*size, ace_sz, size)) { 647 kfree(sid); 648 break; 649 } 650 (*num_aces)++; 651 if (pace->e_tag == ACL_USER) 652 ntace->access_req |= 653 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 654 655 if (S_ISDIR(fattr->cf_mode) && 656 (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) { 657 ntace = (struct smb_ace *)((char *)pndace + *size); 658 ace_sz = fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 659 0x03, pace->e_perm, 0777); 660 if (check_add_overflow(*size, ace_sz, size)) { 661 kfree(sid); 662 break; 663 } 664 (*num_aces)++; 665 if (pace->e_tag == ACL_USER) 666 ntace->access_req |= 667 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 668 } 669 670 pass_same_sid: 671 kfree(sid); 672 } 673 674 if (nt_aces_num) 675 return; 676 677 posix_default_acl: 678 if (!fattr->cf_dacls) 679 return; 680 681 pace = fattr->cf_dacls->a_entries; 682 for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) { 683 sid = kmalloc_obj(struct smb_sid, KSMBD_DEFAULT_GFP); 684 if (!sid) 685 break; 686 687 if (pace->e_tag == ACL_USER) { 688 uid_t uid; 689 690 uid = posix_acl_uid_translate(idmap, pace); 691 id_to_sid(uid, SIDCREATOR_OWNER, sid); 692 } else if (pace->e_tag == ACL_GROUP) { 693 gid_t gid; 694 695 gid = posix_acl_gid_translate(idmap, pace); 696 id_to_sid(gid, SIDCREATOR_GROUP, sid); 697 } else { 698 kfree(sid); 699 continue; 700 } 701 702 ntace = (struct smb_ace *)((char *)pndace + *size); 703 ace_sz = fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b, 704 pace->e_perm, 0777); 705 if (check_add_overflow(*size, ace_sz, size)) { 706 kfree(sid); 707 break; 708 } 709 (*num_aces)++; 710 if (pace->e_tag == ACL_USER) 711 ntace->access_req |= 712 FILE_DELETE_LE | FILE_DELETE_CHILD_LE; 713 kfree(sid); 714 } 715 } 716 717 static void set_ntacl_dacl(struct mnt_idmap *idmap, 718 struct smb_acl *pndacl, 719 struct smb_acl *nt_dacl, 720 unsigned int aces_size, 721 const struct smb_sid *pownersid, 722 const struct smb_sid *pgrpsid, 723 struct smb_fattr *fattr) 724 { 725 struct smb_ace *ntace, *pndace; 726 u16 nt_num_aces = le16_to_cpu(nt_dacl->num_aces), num_aces = 0; 727 unsigned short size = 0; 728 int i; 729 730 pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl)); 731 if (nt_num_aces) { 732 ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl)); 733 for (i = 0; i < nt_num_aces; i++) { 734 unsigned short nt_ace_size; 735 736 if (offsetof(struct smb_ace, access_req) > aces_size) 737 break; 738 739 nt_ace_size = le16_to_cpu(ntace->size); 740 if (nt_ace_size > aces_size) 741 break; 742 743 memcpy((char *)pndace + size, ntace, nt_ace_size); 744 if (check_add_overflow(size, nt_ace_size, &size)) 745 break; 746 aces_size -= nt_ace_size; 747 ntace = (struct smb_ace *)((char *)ntace + nt_ace_size); 748 num_aces++; 749 } 750 } 751 752 set_posix_acl_entries_dacl(idmap, pndace, fattr, 753 &num_aces, &size, nt_num_aces); 754 pndacl->num_aces = cpu_to_le16(num_aces); 755 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size); 756 } 757 758 static void set_mode_dacl(struct mnt_idmap *idmap, 759 struct smb_acl *pndacl, struct smb_fattr *fattr) 760 { 761 struct smb_ace *pace, *pndace; 762 u16 num_aces = 0; 763 u16 size = 0, ace_size = 0; 764 uid_t uid; 765 const struct smb_sid *sid; 766 767 pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl)); 768 769 if (fattr->cf_acls) { 770 set_posix_acl_entries_dacl(idmap, pndace, fattr, 771 &num_aces, &size, num_aces); 772 goto out; 773 } 774 775 /* owner RID */ 776 uid = from_kuid(&init_user_ns, fattr->cf_uid); 777 if (uid) 778 sid = &server_conf.domain_sid; 779 else 780 sid = &sid_unix_users; 781 ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0, 782 fattr->cf_mode, 0700); 783 pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid); 784 pace->size = cpu_to_le16(ace_size + 4); 785 size += le16_to_cpu(pace->size); 786 pace = (struct smb_ace *)((char *)pndace + size); 787 788 /* Group RID */ 789 ace_size = fill_ace_for_sid(pace, &sid_unix_groups, 790 ACCESS_ALLOWED, 0, fattr->cf_mode, 0070); 791 pace->sid.sub_auth[pace->sid.num_subauth++] = 792 cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid)); 793 pace->size = cpu_to_le16(ace_size + 4); 794 size += le16_to_cpu(pace->size); 795 pace = (struct smb_ace *)((char *)pndace + size); 796 num_aces = 3; 797 798 if (S_ISDIR(fattr->cf_mode)) { 799 pace = (struct smb_ace *)((char *)pndace + size); 800 801 /* creator owner */ 802 size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED, 803 0x0b, fattr->cf_mode, 0700); 804 pace = (struct smb_ace *)((char *)pndace + size); 805 806 /* creator group */ 807 size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED, 808 0x0b, fattr->cf_mode, 0070); 809 pace = (struct smb_ace *)((char *)pndace + size); 810 num_aces = 5; 811 } 812 813 /* other */ 814 size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0, 815 fattr->cf_mode, 0007); 816 817 out: 818 pndacl->num_aces = cpu_to_le16(num_aces); 819 pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size); 820 } 821 822 static int parse_sid(struct smb_sid *psid, char *end_of_acl) 823 { 824 /* 825 * validate that we do not go past end of ACL - sid must be at least 8 826 * bytes long (assuming no sub-auths - e.g. the null SID 827 */ 828 if (end_of_acl < (char *)psid + 8) { 829 pr_err("ACL too small to parse SID %p\n", psid); 830 return -EINVAL; 831 } 832 833 if (!psid->num_subauth) 834 return 0; 835 836 if (psid->num_subauth > SID_MAX_SUB_AUTHORITIES || 837 end_of_acl < (char *)psid + 8 + sizeof(__le32) * psid->num_subauth) 838 return -EINVAL; 839 840 return 0; 841 } 842 843 /* Convert CIFS ACL to POSIX form */ 844 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd, 845 int acl_len, struct smb_fattr *fattr) 846 { 847 int rc = 0; 848 struct smb_sid *owner_sid_ptr, *group_sid_ptr; 849 struct smb_acl *dacl_ptr; /* no need for SACL ptr */ 850 char *end_of_acl = ((char *)pntsd) + acl_len; 851 __u32 dacloffset; 852 int pntsd_type; 853 854 if (!pntsd) 855 return -EIO; 856 857 if (acl_len < sizeof(struct smb_ntsd)) 858 return -EINVAL; 859 860 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + 861 le32_to_cpu(pntsd->osidoffset)); 862 group_sid_ptr = (struct smb_sid *)((char *)pntsd + 863 le32_to_cpu(pntsd->gsidoffset)); 864 dacloffset = le32_to_cpu(pntsd->dacloffset); 865 dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset); 866 ksmbd_debug(SMB, 867 "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n", 868 pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset), 869 le32_to_cpu(pntsd->gsidoffset), 870 le32_to_cpu(pntsd->sacloffset), dacloffset); 871 872 pntsd_type = le16_to_cpu(pntsd->type); 873 if (!(pntsd_type & DACL_PRESENT)) { 874 ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n"); 875 return rc; 876 } 877 878 pntsd->type = cpu_to_le16(DACL_PRESENT); 879 880 if (pntsd->osidoffset) { 881 if (le32_to_cpu(pntsd->osidoffset) < sizeof(struct smb_ntsd)) 882 return -EINVAL; 883 884 rc = parse_sid(owner_sid_ptr, end_of_acl); 885 if (rc) { 886 pr_err("%s: Error %d parsing Owner SID\n", __func__, rc); 887 return rc; 888 } 889 890 rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr); 891 if (rc) { 892 pr_err("%s: Error %d mapping Owner SID to uid\n", 893 __func__, rc); 894 owner_sid_ptr = NULL; 895 } 896 } 897 898 if (pntsd->gsidoffset) { 899 if (le32_to_cpu(pntsd->gsidoffset) < sizeof(struct smb_ntsd)) 900 return -EINVAL; 901 902 rc = parse_sid(group_sid_ptr, end_of_acl); 903 if (rc) { 904 pr_err("%s: Error %d mapping Owner SID to gid\n", 905 __func__, rc); 906 return rc; 907 } 908 rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr); 909 if (rc) { 910 pr_err("%s: Error %d mapping Group SID to gid\n", 911 __func__, rc); 912 group_sid_ptr = NULL; 913 } 914 } 915 916 if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) == 917 (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) 918 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED); 919 if (pntsd_type & DACL_PROTECTED) 920 pntsd->type |= cpu_to_le16(DACL_PROTECTED); 921 922 if (dacloffset) { 923 if (dacloffset < sizeof(struct smb_ntsd)) 924 return -EINVAL; 925 926 parse_dacl(idmap, dacl_ptr, end_of_acl, 927 owner_sid_ptr, group_sid_ptr, fattr); 928 } 929 930 return 0; 931 } 932 933 size_t smb_acl_sec_desc_scratch_len(struct smb_fattr *fattr, 934 struct smb_ntsd *ppntsd, int ppntsd_size, int addition_info) 935 { 936 size_t len = sizeof(struct smb_ntsd); 937 size_t tmp; 938 939 if (addition_info & OWNER_SECINFO) 940 len += sizeof(struct smb_sid); 941 if (addition_info & GROUP_SECINFO) 942 len += sizeof(struct smb_sid); 943 if (!(addition_info & DACL_SECINFO)) 944 return len; 945 946 len += sizeof(struct smb_acl); 947 if (ppntsd && ppntsd_size > 0) { 948 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset); 949 950 if (dacl_offset < ppntsd_size && 951 check_add_overflow(len, ppntsd_size - dacl_offset, &len)) 952 return 0; 953 } 954 955 if (fattr->cf_acls) { 956 if (check_mul_overflow((size_t)fattr->cf_acls->a_count, 957 2 * sizeof(struct smb_ace), &tmp) || 958 check_add_overflow(len, tmp, &len)) 959 return 0; 960 } else { 961 /* default/minimum DACL */ 962 if (check_add_overflow(len, 5 * sizeof(struct smb_ace), &len)) 963 return 0; 964 } 965 966 if (fattr->cf_dacls) { 967 if (check_mul_overflow((size_t)fattr->cf_dacls->a_count, 968 sizeof(struct smb_ace), &tmp) || 969 check_add_overflow(len, tmp, &len)) 970 return 0; 971 } 972 973 return len; 974 } 975 976 /* Convert permission bits from mode to equivalent CIFS ACL */ 977 int build_sec_desc(struct mnt_idmap *idmap, 978 struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd, 979 int ppntsd_size, int addition_info, __u32 *secdesclen, 980 struct smb_fattr *fattr) 981 { 982 int rc = 0; 983 __u32 offset; 984 struct smb_sid *owner_sid_ptr, *group_sid_ptr; 985 struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr; 986 struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */ 987 uid_t uid; 988 gid_t gid; 989 unsigned int sid_type = SIDOWNER; 990 991 nowner_sid_ptr = kmalloc_obj(struct smb_sid, KSMBD_DEFAULT_GFP); 992 if (!nowner_sid_ptr) 993 return -ENOMEM; 994 995 uid = from_kuid(&init_user_ns, fattr->cf_uid); 996 if (!uid) 997 sid_type = SIDUNIX_USER; 998 id_to_sid(uid, sid_type, nowner_sid_ptr); 999 1000 ngroup_sid_ptr = kmalloc_obj(struct smb_sid, KSMBD_DEFAULT_GFP); 1001 if (!ngroup_sid_ptr) { 1002 kfree(nowner_sid_ptr); 1003 return -ENOMEM; 1004 } 1005 1006 gid = from_kgid(&init_user_ns, fattr->cf_gid); 1007 id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr); 1008 1009 offset = sizeof(struct smb_ntsd); 1010 pntsd->sacloffset = 0; 1011 pntsd->revision = cpu_to_le16(1); 1012 pntsd->type = cpu_to_le16(SELF_RELATIVE); 1013 if (ppntsd) 1014 pntsd->type |= ppntsd->type; 1015 1016 if (addition_info & OWNER_SECINFO) { 1017 pntsd->osidoffset = cpu_to_le32(offset); 1018 owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset); 1019 smb_copy_sid(owner_sid_ptr, nowner_sid_ptr); 1020 offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4); 1021 } 1022 1023 if (addition_info & GROUP_SECINFO) { 1024 pntsd->gsidoffset = cpu_to_le32(offset); 1025 group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset); 1026 smb_copy_sid(group_sid_ptr, ngroup_sid_ptr); 1027 offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4); 1028 } 1029 1030 if (addition_info & DACL_SECINFO) { 1031 pntsd->type |= cpu_to_le16(DACL_PRESENT); 1032 dacl_ptr = (struct smb_acl *)((char *)pntsd + offset); 1033 dacl_ptr->revision = cpu_to_le16(2); 1034 dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl)); 1035 dacl_ptr->num_aces = 0; 1036 1037 if (!ppntsd) { 1038 set_mode_dacl(idmap, dacl_ptr, fattr); 1039 } else { 1040 struct smb_acl *ppdacl_ptr; 1041 unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset); 1042 int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset; 1043 1044 if (!dacl_offset || 1045 (dacl_offset + sizeof(struct smb_acl) > ppntsd_size)) 1046 goto out; 1047 1048 ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset); 1049 ppdacl_size = le16_to_cpu(ppdacl_ptr->size); 1050 if (ppdacl_size > ntacl_size || 1051 ppdacl_size < sizeof(struct smb_acl)) 1052 goto out; 1053 1054 set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr, 1055 ntacl_size - sizeof(struct smb_acl), 1056 nowner_sid_ptr, ngroup_sid_ptr, 1057 fattr); 1058 } 1059 pntsd->dacloffset = cpu_to_le32(offset); 1060 offset += le16_to_cpu(dacl_ptr->size); 1061 } 1062 1063 out: 1064 kfree(nowner_sid_ptr); 1065 kfree(ngroup_sid_ptr); 1066 *secdesclen = offset; 1067 return rc; 1068 } 1069 1070 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type, 1071 u8 flags, __le32 access_req) 1072 { 1073 ace->type = type; 1074 ace->flags = flags; 1075 ace->access_req = access_req; 1076 smb_copy_sid(&ace->sid, sid); 1077 ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + 1078 (ace->sid.num_subauth * 4)); 1079 } 1080 1081 static int smb_append_inherited_ace(struct smb_ace **ace, int *nt_size, 1082 u16 *ace_cnt, const struct smb_sid *sid, 1083 u8 type, u8 flags, __le32 access_req) 1084 { 1085 int ace_size; 1086 1087 smb_set_ace(*ace, sid, type, flags, access_req); 1088 ace_size = le16_to_cpu((*ace)->size); 1089 /* pdacl->size is __le16 and includes struct smb_acl. */ 1090 if (check_add_overflow(*nt_size, ace_size, nt_size) || 1091 *nt_size > U16_MAX - (int)sizeof(struct smb_acl)) 1092 return -EINVAL; 1093 1094 (*ace_cnt)++; 1095 *ace = (struct smb_ace *)((char *)*ace + ace_size); 1096 return 0; 1097 } 1098 1099 static int smb_validate_ntsd_sid(struct smb_ntsd *pntsd, size_t pntsd_size, 1100 unsigned int sid_offset, struct smb_sid **sid, 1101 size_t *sid_size) 1102 { 1103 size_t sid_end; 1104 1105 *sid = NULL; 1106 *sid_size = 0; 1107 1108 if (!sid_offset) 1109 return 0; 1110 1111 if (sid_offset < sizeof(struct smb_ntsd) || 1112 check_add_overflow(sid_offset, (size_t)CIFS_SID_BASE_SIZE, 1113 &sid_end) || 1114 sid_end > pntsd_size) 1115 return -EINVAL; 1116 1117 *sid = (struct smb_sid *)((char *)pntsd + sid_offset); 1118 if ((*sid)->num_subauth > SID_MAX_SUB_AUTHORITIES) 1119 return -EINVAL; 1120 1121 if (check_add_overflow((size_t)CIFS_SID_BASE_SIZE, 1122 sizeof(__le32) * (size_t)(*sid)->num_subauth, 1123 &sid_end)) 1124 return -EINVAL; 1125 1126 if (sid_offset > pntsd_size || sid_end > pntsd_size - sid_offset) 1127 return -EINVAL; 1128 1129 *sid_size = sid_end; 1130 return 0; 1131 } 1132 1133 int smb_inherit_dacl(struct ksmbd_conn *conn, 1134 const struct path *path, 1135 unsigned int uid, unsigned int gid) 1136 { 1137 const struct smb_sid *psid, *creator = NULL; 1138 struct smb_ace *parent_aces, *aces; 1139 struct smb_acl *parent_pdacl; 1140 struct smb_ntsd *parent_pntsd = NULL; 1141 struct smb_sid owner_sid, group_sid; 1142 struct dentry *parent = path->dentry->d_parent; 1143 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1144 int inherited_flags = 0, flags = 0, i, nt_size = 0, pdacl_size; 1145 int rc = 0, pntsd_type, ppntsd_size, acl_len, aces_size; 1146 unsigned int dacloffset; 1147 size_t dacl_struct_end; 1148 u16 num_aces, ace_cnt = 0; 1149 char *aces_base; 1150 bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode); 1151 1152 ppntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap, 1153 parent, &parent_pntsd); 1154 if (ppntsd_size <= 0) 1155 return -ENOENT; 1156 1157 dacloffset = le32_to_cpu(parent_pntsd->dacloffset); 1158 if (!dacloffset || 1159 check_add_overflow(dacloffset, sizeof(struct smb_acl), &dacl_struct_end) || 1160 dacl_struct_end > (size_t)ppntsd_size) { 1161 rc = -EINVAL; 1162 goto free_parent_pntsd; 1163 } 1164 1165 parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset); 1166 acl_len = ppntsd_size - dacloffset; 1167 num_aces = le16_to_cpu(parent_pdacl->num_aces); 1168 pntsd_type = le16_to_cpu(parent_pntsd->type); 1169 pdacl_size = le16_to_cpu(parent_pdacl->size); 1170 1171 if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) { 1172 rc = -EINVAL; 1173 goto free_parent_pntsd; 1174 } 1175 1176 aces_size = pdacl_size - sizeof(struct smb_acl); 1177 1178 /* 1179 * Validate num_aces against the DACL payload before allocating. 1180 * Each ACE must be at least as large as its fixed-size header 1181 * (up to the SID base), so num_aces cannot exceed the payload 1182 * divided by the minimum ACE size. This mirrors the existing 1183 * check in parse_dacl(). 1184 */ 1185 if (num_aces > aces_size / (offsetof(struct smb_ace, sid) + 1186 offsetof(struct smb_sid, sub_auth) + 1187 sizeof(__le16))) { 1188 rc = -EINVAL; 1189 goto free_parent_pntsd; 1190 } 1191 1192 aces_base = kmalloc_array(num_aces * 2, sizeof(struct smb_ace), 1193 KSMBD_DEFAULT_GFP); 1194 if (!aces_base) { 1195 rc = -ENOMEM; 1196 goto free_parent_pntsd; 1197 } 1198 1199 aces = (struct smb_ace *)aces_base; 1200 parent_aces = (struct smb_ace *)((char *)parent_pdacl + 1201 sizeof(struct smb_acl)); 1202 1203 if (pntsd_type & DACL_AUTO_INHERITED) 1204 inherited_flags = INHERITED_ACE; 1205 1206 for (i = 0; i < num_aces; i++) { 1207 int pace_size; 1208 1209 if (aces_size < offsetof(struct smb_ace, sid) + 1210 CIFS_SID_BASE_SIZE) 1211 break; 1212 1213 pace_size = le16_to_cpu(parent_aces->size); 1214 if (pace_size > aces_size || 1215 pace_size < offsetof(struct smb_ace, sid) + 1216 CIFS_SID_BASE_SIZE) 1217 break; 1218 1219 if (parent_aces->sid.num_subauth > SID_MAX_SUB_AUTHORITIES || 1220 pace_size < offsetof(struct smb_ace, sid) + 1221 CIFS_SID_BASE_SIZE + 1222 sizeof(__le32) * parent_aces->sid.num_subauth) 1223 break; 1224 1225 aces_size -= pace_size; 1226 1227 flags = parent_aces->flags; 1228 if (!smb_inherit_flags(flags, is_dir)) 1229 goto pass; 1230 if (is_dir) { 1231 flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE); 1232 if (!(flags & CONTAINER_INHERIT_ACE)) 1233 flags |= INHERIT_ONLY_ACE; 1234 if (flags & NO_PROPAGATE_INHERIT_ACE) 1235 flags = 0; 1236 } else { 1237 flags = 0; 1238 } 1239 1240 if (!compare_sids(&creator_owner, &parent_aces->sid)) { 1241 creator = &creator_owner; 1242 id_to_sid(uid, SIDOWNER, &owner_sid); 1243 psid = &owner_sid; 1244 } else if (!compare_sids(&creator_group, &parent_aces->sid)) { 1245 creator = &creator_group; 1246 id_to_sid(gid, SIDUNIX_GROUP, &group_sid); 1247 psid = &group_sid; 1248 } else { 1249 creator = NULL; 1250 psid = &parent_aces->sid; 1251 } 1252 1253 if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) { 1254 rc = smb_append_inherited_ace(&aces, &nt_size, &ace_cnt, 1255 psid, parent_aces->type, 1256 inherited_flags, 1257 parent_aces->access_req); 1258 if (rc) 1259 goto free_aces_base; 1260 flags |= INHERIT_ONLY_ACE; 1261 psid = creator; 1262 } else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) { 1263 psid = &parent_aces->sid; 1264 } 1265 1266 rc = smb_append_inherited_ace(&aces, &nt_size, &ace_cnt, psid, 1267 parent_aces->type, 1268 flags | inherited_flags, 1269 parent_aces->access_req); 1270 if (rc) 1271 goto free_aces_base; 1272 pass: 1273 parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size); 1274 } 1275 1276 if (nt_size > 0) { 1277 struct smb_ntsd *pntsd; 1278 struct smb_acl *pdacl; 1279 struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL; 1280 size_t powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size; 1281 size_t pntsd_alloc_size; 1282 1283 rc = smb_validate_ntsd_sid(parent_pntsd, ppntsd_size, 1284 le32_to_cpu(parent_pntsd->osidoffset), 1285 &powner_sid, &powner_sid_size); 1286 if (rc) 1287 goto free_aces_base; 1288 rc = smb_validate_ntsd_sid(parent_pntsd, ppntsd_size, 1289 le32_to_cpu(parent_pntsd->gsidoffset), 1290 &pgroup_sid, &pgroup_sid_size); 1291 if (rc) 1292 goto free_aces_base; 1293 1294 if (check_add_overflow(sizeof(struct smb_ntsd), 1295 (size_t)powner_sid_size, 1296 &pntsd_alloc_size) || 1297 check_add_overflow(pntsd_alloc_size, 1298 (size_t)pgroup_sid_size, 1299 &pntsd_alloc_size) || 1300 check_add_overflow(pntsd_alloc_size, sizeof(struct smb_acl), 1301 &pntsd_alloc_size) || 1302 check_add_overflow(pntsd_alloc_size, (size_t)nt_size, 1303 &pntsd_alloc_size)) { 1304 rc = -EINVAL; 1305 goto free_aces_base; 1306 } 1307 1308 pntsd = kzalloc(pntsd_alloc_size, KSMBD_DEFAULT_GFP); 1309 if (!pntsd) { 1310 rc = -ENOMEM; 1311 goto free_aces_base; 1312 } 1313 1314 pntsd->revision = cpu_to_le16(1); 1315 pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT); 1316 if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED) 1317 pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED); 1318 pntsd_size = sizeof(struct smb_ntsd); 1319 pntsd->osidoffset = parent_pntsd->osidoffset; 1320 pntsd->gsidoffset = parent_pntsd->gsidoffset; 1321 pntsd->dacloffset = parent_pntsd->dacloffset; 1322 1323 if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size > 1324 pntsd_alloc_size) { 1325 rc = -EINVAL; 1326 kfree(pntsd); 1327 goto free_aces_base; 1328 } 1329 1330 if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size > 1331 pntsd_alloc_size) { 1332 rc = -EINVAL; 1333 kfree(pntsd); 1334 goto free_aces_base; 1335 } 1336 1337 if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size > 1338 pntsd_alloc_size) { 1339 rc = -EINVAL; 1340 kfree(pntsd); 1341 goto free_aces_base; 1342 } 1343 1344 if (pntsd->osidoffset) { 1345 struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd + 1346 le32_to_cpu(pntsd->osidoffset)); 1347 memcpy(owner_sid, powner_sid, powner_sid_size); 1348 pntsd_size += powner_sid_size; 1349 } 1350 1351 if (pntsd->gsidoffset) { 1352 struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd + 1353 le32_to_cpu(pntsd->gsidoffset)); 1354 memcpy(group_sid, pgroup_sid, pgroup_sid_size); 1355 pntsd_size += pgroup_sid_size; 1356 } 1357 1358 if (pntsd->dacloffset) { 1359 struct smb_ace *pace; 1360 1361 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset)); 1362 pdacl->revision = cpu_to_le16(2); 1363 pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size); 1364 pdacl->num_aces = cpu_to_le16(ace_cnt); 1365 pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1366 memcpy(pace, aces_base, nt_size); 1367 pntsd_size += sizeof(struct smb_acl) + nt_size; 1368 } 1369 1370 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size, false); 1371 kfree(pntsd); 1372 } 1373 1374 free_aces_base: 1375 kfree(aces_base); 1376 free_parent_pntsd: 1377 kfree(parent_pntsd); 1378 return rc; 1379 } 1380 1381 bool smb_inherit_flags(int flags, bool is_dir) 1382 { 1383 if (!is_dir) 1384 return (flags & OBJECT_INHERIT_ACE) != 0; 1385 1386 if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE)) 1387 return true; 1388 1389 if (flags & CONTAINER_INHERIT_ACE) 1390 return true; 1391 return false; 1392 } 1393 1394 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path, 1395 __le32 *pdaccess, int uid) 1396 { 1397 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1398 struct smb_ntsd *pntsd = NULL; 1399 struct smb_acl *pdacl; 1400 struct posix_acl *posix_acls; 1401 int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size; 1402 unsigned int dacl_offset; 1403 size_t dacl_struct_end; 1404 struct smb_sid sid; 1405 int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE); 1406 struct smb_ace *ace; 1407 int i, found = 0; 1408 unsigned int access_bits = 0; 1409 struct smb_ace *others_ace = NULL; 1410 struct posix_acl_entry *pa_entry; 1411 unsigned int sid_type = SIDOWNER; 1412 unsigned short ace_size; 1413 1414 ksmbd_debug(SMB, "check permission using windows acl\n"); 1415 pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap, 1416 path->dentry, &pntsd); 1417 if (pntsd_size <= 0 || !pntsd) 1418 goto err_out; 1419 1420 dacl_offset = le32_to_cpu(pntsd->dacloffset); 1421 if (!dacl_offset || 1422 check_add_overflow(dacl_offset, sizeof(struct smb_acl), &dacl_struct_end) || 1423 dacl_struct_end > (size_t)pntsd_size) 1424 goto err_out; 1425 1426 pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset)); 1427 acl_size = pntsd_size - dacl_offset; 1428 pdacl_size = le16_to_cpu(pdacl->size); 1429 1430 if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl)) 1431 goto err_out; 1432 1433 if (!pdacl->num_aces) { 1434 if (!(pdacl_size - sizeof(struct smb_acl)) && 1435 *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) { 1436 rc = -EACCES; 1437 goto err_out; 1438 } 1439 goto err_out; 1440 } 1441 1442 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) { 1443 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES | 1444 DELETE; 1445 1446 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1447 aces_size = acl_size - sizeof(struct smb_acl); 1448 for (i = 0; i < le16_to_cpu(pdacl->num_aces); i++) { 1449 if (aces_size < offsetof(struct smb_ace, sid) + 1450 CIFS_SID_BASE_SIZE) 1451 break; 1452 ace_size = le16_to_cpu(ace->size); 1453 if (ace_size > aces_size || 1454 ace_size < offsetof(struct smb_ace, sid) + 1455 CIFS_SID_BASE_SIZE) 1456 break; 1457 aces_size -= ace_size; 1458 granted |= le32_to_cpu(ace->access_req); 1459 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size)); 1460 } 1461 } 1462 1463 if (!uid) 1464 sid_type = SIDUNIX_USER; 1465 id_to_sid(uid, sid_type, &sid); 1466 1467 ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl)); 1468 aces_size = acl_size - sizeof(struct smb_acl); 1469 for (i = 0; i < le16_to_cpu(pdacl->num_aces); i++) { 1470 if (aces_size < offsetof(struct smb_ace, sid) + 1471 CIFS_SID_BASE_SIZE) 1472 break; 1473 ace_size = le16_to_cpu(ace->size); 1474 if (ace_size > aces_size || 1475 ace_size < offsetof(struct smb_ace, sid) + 1476 CIFS_SID_BASE_SIZE) 1477 break; 1478 aces_size -= ace_size; 1479 1480 if (ace->sid.num_subauth > SID_MAX_SUB_AUTHORITIES || 1481 ace_size < offsetof(struct smb_ace, sid) + CIFS_SID_BASE_SIZE + 1482 sizeof(__le32) * ace->sid.num_subauth) 1483 break; 1484 1485 if (!compare_sids(&sid, &ace->sid) || 1486 !compare_sids(&sid_unix_NFS_mode, &ace->sid)) { 1487 found = 1; 1488 break; 1489 } 1490 if (!compare_sids(&sid_everyone, &ace->sid)) 1491 others_ace = ace; 1492 1493 ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size)); 1494 } 1495 1496 if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) { 1497 granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES | 1498 DELETE; 1499 1500 granted |= le32_to_cpu(ace->access_req); 1501 1502 if (!pdacl->num_aces) 1503 granted = GENERIC_ALL_FLAGS; 1504 } 1505 1506 if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) { 1507 posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS); 1508 if (!IS_ERR_OR_NULL(posix_acls) && !found) { 1509 unsigned int id = -1; 1510 1511 pa_entry = posix_acls->a_entries; 1512 for (i = 0; i < posix_acls->a_count; i++, pa_entry++) { 1513 if (pa_entry->e_tag == ACL_USER) 1514 id = posix_acl_uid_translate(idmap, pa_entry); 1515 else if (pa_entry->e_tag == ACL_GROUP) 1516 id = posix_acl_gid_translate(idmap, pa_entry); 1517 else 1518 continue; 1519 1520 if (id == uid) { 1521 mode_to_access_flags(pa_entry->e_perm, 1522 0777, 1523 &access_bits); 1524 if (!access_bits) 1525 access_bits = 1526 SET_MINIMUM_RIGHTS; 1527 posix_acl_release(posix_acls); 1528 goto check_access_bits; 1529 } 1530 } 1531 } 1532 if (!IS_ERR_OR_NULL(posix_acls)) 1533 posix_acl_release(posix_acls); 1534 } 1535 1536 if (!found) { 1537 if (others_ace) { 1538 ace = others_ace; 1539 } else { 1540 ksmbd_debug(SMB, "Can't find corresponding sid\n"); 1541 rc = -EACCES; 1542 goto err_out; 1543 } 1544 } 1545 1546 switch (ace->type) { 1547 case ACCESS_ALLOWED_ACE_TYPE: 1548 access_bits = le32_to_cpu(ace->access_req); 1549 break; 1550 case ACCESS_DENIED_ACE_TYPE: 1551 case ACCESS_DENIED_CALLBACK_ACE_TYPE: 1552 access_bits = le32_to_cpu(~ace->access_req); 1553 break; 1554 } 1555 1556 check_access_bits: 1557 if (granted & 1558 ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) { 1559 ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n", 1560 granted, le32_to_cpu(ace->access_req)); 1561 rc = -EACCES; 1562 goto err_out; 1563 } 1564 1565 *pdaccess = cpu_to_le32(granted); 1566 err_out: 1567 kfree(pntsd); 1568 return rc; 1569 } 1570 1571 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon, 1572 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len, 1573 bool type_check, bool get_write) 1574 { 1575 int rc; 1576 struct smb_fattr fattr = {{0}}; 1577 struct inode *inode = d_inode(path->dentry); 1578 struct mnt_idmap *idmap = mnt_idmap(path->mnt); 1579 struct iattr newattrs; 1580 1581 fattr.cf_uid = INVALID_UID; 1582 fattr.cf_gid = INVALID_GID; 1583 fattr.cf_mode = inode->i_mode; 1584 1585 rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr); 1586 if (rc) 1587 goto out; 1588 1589 newattrs.ia_valid = ATTR_CTIME; 1590 if (!uid_eq(fattr.cf_uid, INVALID_UID)) { 1591 newattrs.ia_valid |= ATTR_UID; 1592 newattrs.ia_uid = fattr.cf_uid; 1593 } 1594 if (!gid_eq(fattr.cf_gid, INVALID_GID)) { 1595 newattrs.ia_valid |= ATTR_GID; 1596 newattrs.ia_gid = fattr.cf_gid; 1597 } 1598 newattrs.ia_valid |= ATTR_MODE; 1599 newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777); 1600 1601 ksmbd_vfs_remove_acl_xattrs(idmap, path); 1602 /* Update posix acls */ 1603 if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) { 1604 rc = set_posix_acl(idmap, path->dentry, 1605 ACL_TYPE_ACCESS, fattr.cf_acls); 1606 if (rc < 0) 1607 ksmbd_debug(SMB, 1608 "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n", 1609 rc); 1610 if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) { 1611 rc = set_posix_acl(idmap, path->dentry, 1612 ACL_TYPE_DEFAULT, fattr.cf_dacls); 1613 if (rc) 1614 ksmbd_debug(SMB, 1615 "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n", 1616 rc); 1617 } 1618 } 1619 1620 inode_lock(inode); 1621 rc = notify_change(idmap, path->dentry, &newattrs, NULL); 1622 inode_unlock(inode); 1623 if (rc) 1624 goto out; 1625 1626 /* Check it only calling from SD BUFFER context */ 1627 if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT)) 1628 goto out; 1629 1630 if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) { 1631 /* Update WinACL in xattr */ 1632 ksmbd_vfs_remove_sd_xattrs(idmap, path); 1633 ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len, 1634 get_write); 1635 } 1636 1637 out: 1638 posix_acl_release(fattr.cf_acls); 1639 posix_acl_release(fattr.cf_dacls); 1640 return rc; 1641 } 1642 1643 void ksmbd_init_domain(u32 *sub_auth) 1644 { 1645 int i; 1646 1647 memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid)); 1648 for (i = 0; i < 3; ++i) 1649 server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]); 1650 } 1651