xref: /linux/fs/smb/server/smbacl.c (revision d623704bb23901a25bf6d6a40aa16b43a17622eb)
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 (sidtype == SIDOWNER) {
274 		kuid_t uid;
275 		uid_t id;
276 
277 		id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
278 		uid = KUIDT_INIT(id);
279 		uid = from_vfsuid(idmap, &init_user_ns, VFSUIDT_INIT(uid));
280 		if (uid_valid(uid)) {
281 			fattr->cf_uid = uid;
282 			rc = 0;
283 		}
284 	} else {
285 		kgid_t gid;
286 		gid_t id;
287 
288 		id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
289 		gid = KGIDT_INIT(id);
290 		gid = from_vfsgid(idmap, &init_user_ns, VFSGIDT_INIT(gid));
291 		if (gid_valid(gid)) {
292 			fattr->cf_gid = gid;
293 			rc = 0;
294 		}
295 	}
296 
297 	return rc;
298 }
299 
300 void posix_state_to_acl(struct posix_acl_state *state,
301 			struct posix_acl_entry *pace)
302 {
303 	int i;
304 
305 	pace->e_tag = ACL_USER_OBJ;
306 	pace->e_perm = state->owner.allow;
307 	for (i = 0; i < state->users->n; i++) {
308 		pace++;
309 		pace->e_tag = ACL_USER;
310 		pace->e_uid = state->users->aces[i].uid;
311 		pace->e_perm = state->users->aces[i].perms.allow;
312 	}
313 
314 	pace++;
315 	pace->e_tag = ACL_GROUP_OBJ;
316 	pace->e_perm = state->group.allow;
317 
318 	for (i = 0; i < state->groups->n; i++) {
319 		pace++;
320 		pace->e_tag = ACL_GROUP;
321 		pace->e_gid = state->groups->aces[i].gid;
322 		pace->e_perm = state->groups->aces[i].perms.allow;
323 	}
324 
325 	if (state->users->n || state->groups->n) {
326 		pace++;
327 		pace->e_tag = ACL_MASK;
328 		pace->e_perm = state->mask.allow;
329 	}
330 
331 	pace++;
332 	pace->e_tag = ACL_OTHER;
333 	pace->e_perm = state->other.allow;
334 }
335 
336 int init_acl_state(struct posix_acl_state *state, int cnt)
337 {
338 	int alloc;
339 
340 	memset(state, 0, sizeof(struct posix_acl_state));
341 	/*
342 	 * In the worst case, each individual acl could be for a distinct
343 	 * named user or group, but we don't know which, so we allocate
344 	 * enough space for either:
345 	 */
346 	alloc = sizeof(struct posix_ace_state_array)
347 		+ cnt * sizeof(struct posix_user_ace_state);
348 	state->users = kzalloc(alloc, GFP_KERNEL);
349 	if (!state->users)
350 		return -ENOMEM;
351 	state->groups = kzalloc(alloc, GFP_KERNEL);
352 	if (!state->groups) {
353 		kfree(state->users);
354 		return -ENOMEM;
355 	}
356 	return 0;
357 }
358 
359 void free_acl_state(struct posix_acl_state *state)
360 {
361 	kfree(state->users);
362 	kfree(state->groups);
363 }
364 
365 static void parse_dacl(struct mnt_idmap *idmap,
366 		       struct smb_acl *pdacl, char *end_of_acl,
367 		       struct smb_sid *pownersid, struct smb_sid *pgrpsid,
368 		       struct smb_fattr *fattr)
369 {
370 	int i, ret;
371 	int num_aces = 0;
372 	unsigned int acl_size;
373 	char *acl_base;
374 	struct smb_ace **ppace;
375 	struct posix_acl_entry *cf_pace, *cf_pdace;
376 	struct posix_acl_state acl_state, default_acl_state;
377 	umode_t mode = 0, acl_mode;
378 	bool owner_found = false, group_found = false, others_found = false;
379 
380 	if (!pdacl)
381 		return;
382 
383 	/* validate that we do not go past end of acl */
384 	if (end_of_acl < (char *)pdacl + sizeof(struct smb_acl) ||
385 	    end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
386 		pr_err("ACL too small to parse DACL\n");
387 		return;
388 	}
389 
390 	ksmbd_debug(SMB, "DACL revision %d size %d num aces %d\n",
391 		    le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
392 		    le32_to_cpu(pdacl->num_aces));
393 
394 	acl_base = (char *)pdacl;
395 	acl_size = sizeof(struct smb_acl);
396 
397 	num_aces = le32_to_cpu(pdacl->num_aces);
398 	if (num_aces <= 0)
399 		return;
400 
401 	if (num_aces > ULONG_MAX / sizeof(struct smb_ace *))
402 		return;
403 
404 	ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
405 	if (!ppace)
406 		return;
407 
408 	ret = init_acl_state(&acl_state, num_aces);
409 	if (ret)
410 		return;
411 	ret = init_acl_state(&default_acl_state, num_aces);
412 	if (ret) {
413 		free_acl_state(&acl_state);
414 		return;
415 	}
416 
417 	/*
418 	 * reset rwx permissions for user/group/other.
419 	 * Also, if num_aces is 0 i.e. DACL has no ACEs,
420 	 * user/group/other have no permissions
421 	 */
422 	for (i = 0; i < num_aces; ++i) {
423 		if (end_of_acl - acl_base < acl_size)
424 			break;
425 
426 		ppace[i] = (struct smb_ace *)(acl_base + acl_size);
427 		acl_base = (char *)ppace[i];
428 		acl_size = offsetof(struct smb_ace, sid) +
429 			offsetof(struct smb_sid, sub_auth);
430 
431 		if (end_of_acl - acl_base < acl_size ||
432 		    ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
433 		    (end_of_acl - acl_base <
434 		     acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
435 		    (le16_to_cpu(ppace[i]->size) <
436 		     acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
437 			break;
438 
439 		acl_size = le16_to_cpu(ppace[i]->size);
440 		ppace[i]->access_req =
441 			smb_map_generic_desired_access(ppace[i]->access_req);
442 
443 		if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
444 			fattr->cf_mode =
445 				le32_to_cpu(ppace[i]->sid.sub_auth[2]);
446 			break;
447 		} else if (!compare_sids(&ppace[i]->sid, pownersid)) {
448 			acl_mode = access_flags_to_mode(fattr,
449 							ppace[i]->access_req,
450 							ppace[i]->type);
451 			acl_mode &= 0700;
452 
453 			if (!owner_found) {
454 				mode &= ~(0700);
455 				mode |= acl_mode;
456 			}
457 			owner_found = true;
458 		} else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
459 			   ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
460 			    DOMAIN_USER_RID_LE) {
461 			acl_mode = access_flags_to_mode(fattr,
462 							ppace[i]->access_req,
463 							ppace[i]->type);
464 			acl_mode &= 0070;
465 			if (!group_found) {
466 				mode &= ~(0070);
467 				mode |= acl_mode;
468 			}
469 			group_found = true;
470 		} else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
471 			acl_mode = access_flags_to_mode(fattr,
472 							ppace[i]->access_req,
473 							ppace[i]->type);
474 			acl_mode &= 0007;
475 			if (!others_found) {
476 				mode &= ~(0007);
477 				mode |= acl_mode;
478 			}
479 			others_found = true;
480 		} else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
481 			continue;
482 		} else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
483 			continue;
484 		} else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
485 			continue;
486 		} else {
487 			struct smb_fattr temp_fattr;
488 
489 			acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
490 							ppace[i]->type);
491 			temp_fattr.cf_uid = INVALID_UID;
492 			ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr);
493 			if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
494 				pr_err("%s: Error %d mapping Owner SID to uid\n",
495 				       __func__, ret);
496 				continue;
497 			}
498 
499 			acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
500 			acl_state.users->aces[acl_state.users->n].uid =
501 				temp_fattr.cf_uid;
502 			acl_state.users->aces[acl_state.users->n++].perms.allow =
503 				((acl_mode & 0700) >> 6) | 0004;
504 			default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
505 			default_acl_state.users->aces[default_acl_state.users->n].uid =
506 				temp_fattr.cf_uid;
507 			default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
508 				((acl_mode & 0700) >> 6) | 0004;
509 		}
510 	}
511 	kfree(ppace);
512 
513 	if (owner_found) {
514 		/* The owner must be set to at least read-only. */
515 		acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
516 		acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
517 		acl_state.users->aces[acl_state.users->n++].perms.allow =
518 			((mode & 0700) >> 6) | 0004;
519 		default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
520 		default_acl_state.users->aces[default_acl_state.users->n].uid =
521 			fattr->cf_uid;
522 		default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
523 			((mode & 0700) >> 6) | 0004;
524 	}
525 
526 	if (group_found) {
527 		acl_state.group.allow = (mode & 0070) >> 3;
528 		acl_state.groups->aces[acl_state.groups->n].gid =
529 			fattr->cf_gid;
530 		acl_state.groups->aces[acl_state.groups->n++].perms.allow =
531 			(mode & 0070) >> 3;
532 		default_acl_state.group.allow = (mode & 0070) >> 3;
533 		default_acl_state.groups->aces[default_acl_state.groups->n].gid =
534 			fattr->cf_gid;
535 		default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
536 			(mode & 0070) >> 3;
537 	}
538 
539 	if (others_found) {
540 		fattr->cf_mode &= ~(0007);
541 		fattr->cf_mode |= mode & 0007;
542 
543 		acl_state.other.allow = mode & 0007;
544 		default_acl_state.other.allow = mode & 0007;
545 	}
546 
547 	if (acl_state.users->n || acl_state.groups->n) {
548 		acl_state.mask.allow = 0x07;
549 
550 		if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
551 			fattr->cf_acls =
552 				posix_acl_alloc(acl_state.users->n +
553 					acl_state.groups->n + 4, GFP_KERNEL);
554 			if (fattr->cf_acls) {
555 				cf_pace = fattr->cf_acls->a_entries;
556 				posix_state_to_acl(&acl_state, cf_pace);
557 			}
558 		}
559 	}
560 
561 	if (default_acl_state.users->n || default_acl_state.groups->n) {
562 		default_acl_state.mask.allow = 0x07;
563 
564 		if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
565 			fattr->cf_dacls =
566 				posix_acl_alloc(default_acl_state.users->n +
567 				default_acl_state.groups->n + 4, GFP_KERNEL);
568 			if (fattr->cf_dacls) {
569 				cf_pdace = fattr->cf_dacls->a_entries;
570 				posix_state_to_acl(&default_acl_state, cf_pdace);
571 			}
572 		}
573 	}
574 	free_acl_state(&acl_state);
575 	free_acl_state(&default_acl_state);
576 }
577 
578 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap,
579 				       struct smb_ace *pndace,
580 				       struct smb_fattr *fattr, u32 *num_aces,
581 				       u16 *size, u32 nt_aces_num)
582 {
583 	struct posix_acl_entry *pace;
584 	struct smb_sid *sid;
585 	struct smb_ace *ntace;
586 	int i, j;
587 
588 	if (!fattr->cf_acls)
589 		goto posix_default_acl;
590 
591 	pace = fattr->cf_acls->a_entries;
592 	for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
593 		int flags = 0;
594 
595 		sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
596 		if (!sid)
597 			break;
598 
599 		if (pace->e_tag == ACL_USER) {
600 			uid_t uid;
601 			unsigned int sid_type = SIDOWNER;
602 
603 			uid = posix_acl_uid_translate(idmap, pace);
604 			if (!uid)
605 				sid_type = SIDUNIX_USER;
606 			id_to_sid(uid, sid_type, sid);
607 		} else if (pace->e_tag == ACL_GROUP) {
608 			gid_t gid;
609 
610 			gid = posix_acl_gid_translate(idmap, pace);
611 			id_to_sid(gid, SIDUNIX_GROUP, sid);
612 		} else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
613 			smb_copy_sid(sid, &sid_everyone);
614 		} else {
615 			kfree(sid);
616 			continue;
617 		}
618 		ntace = pndace;
619 		for (j = 0; j < nt_aces_num; j++) {
620 			if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
621 					sid->sub_auth[sid->num_subauth - 1])
622 				goto pass_same_sid;
623 			ntace = (struct smb_ace *)((char *)ntace +
624 					le16_to_cpu(ntace->size));
625 		}
626 
627 		if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
628 			flags = 0x03;
629 
630 		ntace = (struct smb_ace *)((char *)pndace + *size);
631 		*size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
632 				pace->e_perm, 0777);
633 		(*num_aces)++;
634 		if (pace->e_tag == ACL_USER)
635 			ntace->access_req |=
636 				FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
637 
638 		if (S_ISDIR(fattr->cf_mode) &&
639 		    (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
640 			ntace = (struct smb_ace *)((char *)pndace + *size);
641 			*size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
642 					0x03, pace->e_perm, 0777);
643 			(*num_aces)++;
644 			if (pace->e_tag == ACL_USER)
645 				ntace->access_req |=
646 					FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
647 		}
648 
649 pass_same_sid:
650 		kfree(sid);
651 	}
652 
653 	if (nt_aces_num)
654 		return;
655 
656 posix_default_acl:
657 	if (!fattr->cf_dacls)
658 		return;
659 
660 	pace = fattr->cf_dacls->a_entries;
661 	for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
662 		sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
663 		if (!sid)
664 			break;
665 
666 		if (pace->e_tag == ACL_USER) {
667 			uid_t uid;
668 
669 			uid = posix_acl_uid_translate(idmap, pace);
670 			id_to_sid(uid, SIDCREATOR_OWNER, sid);
671 		} else if (pace->e_tag == ACL_GROUP) {
672 			gid_t gid;
673 
674 			gid = posix_acl_gid_translate(idmap, pace);
675 			id_to_sid(gid, SIDCREATOR_GROUP, sid);
676 		} else {
677 			kfree(sid);
678 			continue;
679 		}
680 
681 		ntace = (struct smb_ace *)((char *)pndace + *size);
682 		*size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
683 				pace->e_perm, 0777);
684 		(*num_aces)++;
685 		if (pace->e_tag == ACL_USER)
686 			ntace->access_req |=
687 				FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
688 		kfree(sid);
689 	}
690 }
691 
692 static void set_ntacl_dacl(struct mnt_idmap *idmap,
693 			   struct smb_acl *pndacl,
694 			   struct smb_acl *nt_dacl,
695 			   unsigned int aces_size,
696 			   const struct smb_sid *pownersid,
697 			   const struct smb_sid *pgrpsid,
698 			   struct smb_fattr *fattr)
699 {
700 	struct smb_ace *ntace, *pndace;
701 	int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
702 	unsigned short size = 0;
703 	int i;
704 
705 	pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
706 	if (nt_num_aces) {
707 		ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
708 		for (i = 0; i < nt_num_aces; i++) {
709 			unsigned short nt_ace_size;
710 
711 			if (offsetof(struct smb_ace, access_req) > aces_size)
712 				break;
713 
714 			nt_ace_size = le16_to_cpu(ntace->size);
715 			if (nt_ace_size > aces_size)
716 				break;
717 
718 			memcpy((char *)pndace + size, ntace, nt_ace_size);
719 			size += nt_ace_size;
720 			aces_size -= nt_ace_size;
721 			ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
722 			num_aces++;
723 		}
724 	}
725 
726 	set_posix_acl_entries_dacl(idmap, pndace, fattr,
727 				   &num_aces, &size, nt_num_aces);
728 	pndacl->num_aces = cpu_to_le32(num_aces);
729 	pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
730 }
731 
732 static void set_mode_dacl(struct mnt_idmap *idmap,
733 			  struct smb_acl *pndacl, struct smb_fattr *fattr)
734 {
735 	struct smb_ace *pace, *pndace;
736 	u32 num_aces = 0;
737 	u16 size = 0, ace_size = 0;
738 	uid_t uid;
739 	const struct smb_sid *sid;
740 
741 	pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
742 
743 	if (fattr->cf_acls) {
744 		set_posix_acl_entries_dacl(idmap, pndace, fattr,
745 					   &num_aces, &size, num_aces);
746 		goto out;
747 	}
748 
749 	/* owner RID */
750 	uid = from_kuid(&init_user_ns, fattr->cf_uid);
751 	if (uid)
752 		sid = &server_conf.domain_sid;
753 	else
754 		sid = &sid_unix_users;
755 	ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
756 				    fattr->cf_mode, 0700);
757 	pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
758 	pace->size = cpu_to_le16(ace_size + 4);
759 	size += le16_to_cpu(pace->size);
760 	pace = (struct smb_ace *)((char *)pndace + size);
761 
762 	/* Group RID */
763 	ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
764 				    ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
765 	pace->sid.sub_auth[pace->sid.num_subauth++] =
766 		cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
767 	pace->size = cpu_to_le16(ace_size + 4);
768 	size += le16_to_cpu(pace->size);
769 	pace = (struct smb_ace *)((char *)pndace + size);
770 	num_aces = 3;
771 
772 	if (S_ISDIR(fattr->cf_mode)) {
773 		pace = (struct smb_ace *)((char *)pndace + size);
774 
775 		/* creator owner */
776 		size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
777 					 0x0b, fattr->cf_mode, 0700);
778 		pace = (struct smb_ace *)((char *)pndace + size);
779 
780 		/* creator group */
781 		size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
782 					 0x0b, fattr->cf_mode, 0070);
783 		pace = (struct smb_ace *)((char *)pndace + size);
784 		num_aces = 5;
785 	}
786 
787 	/* other */
788 	size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
789 				 fattr->cf_mode, 0007);
790 
791 out:
792 	pndacl->num_aces = cpu_to_le32(num_aces);
793 	pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
794 }
795 
796 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
797 {
798 	/*
799 	 * validate that we do not go past end of ACL - sid must be at least 8
800 	 * bytes long (assuming no sub-auths - e.g. the null SID
801 	 */
802 	if (end_of_acl < (char *)psid + 8) {
803 		pr_err("ACL too small to parse SID %p\n", psid);
804 		return -EINVAL;
805 	}
806 
807 	return 0;
808 }
809 
810 /* Convert CIFS ACL to POSIX form */
811 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd,
812 		   int acl_len, struct smb_fattr *fattr)
813 {
814 	int rc = 0;
815 	struct smb_sid *owner_sid_ptr, *group_sid_ptr;
816 	struct smb_acl *dacl_ptr; /* no need for SACL ptr */
817 	char *end_of_acl = ((char *)pntsd) + acl_len;
818 	__u32 dacloffset;
819 	int pntsd_type;
820 
821 	if (!pntsd)
822 		return -EIO;
823 
824 	if (acl_len < sizeof(struct smb_ntsd))
825 		return -EINVAL;
826 
827 	owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
828 			le32_to_cpu(pntsd->osidoffset));
829 	group_sid_ptr = (struct smb_sid *)((char *)pntsd +
830 			le32_to_cpu(pntsd->gsidoffset));
831 	dacloffset = le32_to_cpu(pntsd->dacloffset);
832 	dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
833 	ksmbd_debug(SMB,
834 		    "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
835 		    pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
836 		    le32_to_cpu(pntsd->gsidoffset),
837 		    le32_to_cpu(pntsd->sacloffset), dacloffset);
838 
839 	pntsd_type = le16_to_cpu(pntsd->type);
840 	if (!(pntsd_type & DACL_PRESENT)) {
841 		ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
842 		return rc;
843 	}
844 
845 	pntsd->type = cpu_to_le16(DACL_PRESENT);
846 
847 	if (pntsd->osidoffset) {
848 		rc = parse_sid(owner_sid_ptr, end_of_acl);
849 		if (rc) {
850 			pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
851 			return rc;
852 		}
853 
854 		rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr);
855 		if (rc) {
856 			pr_err("%s: Error %d mapping Owner SID to uid\n",
857 			       __func__, rc);
858 			owner_sid_ptr = NULL;
859 		}
860 	}
861 
862 	if (pntsd->gsidoffset) {
863 		rc = parse_sid(group_sid_ptr, end_of_acl);
864 		if (rc) {
865 			pr_err("%s: Error %d mapping Owner SID to gid\n",
866 			       __func__, rc);
867 			return rc;
868 		}
869 		rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr);
870 		if (rc) {
871 			pr_err("%s: Error %d mapping Group SID to gid\n",
872 			       __func__, rc);
873 			group_sid_ptr = NULL;
874 		}
875 	}
876 
877 	if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
878 	    (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
879 		pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
880 	if (pntsd_type & DACL_PROTECTED)
881 		pntsd->type |= cpu_to_le16(DACL_PROTECTED);
882 
883 	if (dacloffset) {
884 		parse_dacl(idmap, dacl_ptr, end_of_acl,
885 			   owner_sid_ptr, group_sid_ptr, fattr);
886 	}
887 
888 	return 0;
889 }
890 
891 /* Convert permission bits from mode to equivalent CIFS ACL */
892 int build_sec_desc(struct mnt_idmap *idmap,
893 		   struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
894 		   int ppntsd_size, int addition_info, __u32 *secdesclen,
895 		   struct smb_fattr *fattr)
896 {
897 	int rc = 0;
898 	__u32 offset;
899 	struct smb_sid *owner_sid_ptr, *group_sid_ptr;
900 	struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
901 	struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
902 	uid_t uid;
903 	gid_t gid;
904 	unsigned int sid_type = SIDOWNER;
905 
906 	nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
907 	if (!nowner_sid_ptr)
908 		return -ENOMEM;
909 
910 	uid = from_kuid(&init_user_ns, fattr->cf_uid);
911 	if (!uid)
912 		sid_type = SIDUNIX_USER;
913 	id_to_sid(uid, sid_type, nowner_sid_ptr);
914 
915 	ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
916 	if (!ngroup_sid_ptr) {
917 		kfree(nowner_sid_ptr);
918 		return -ENOMEM;
919 	}
920 
921 	gid = from_kgid(&init_user_ns, fattr->cf_gid);
922 	id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
923 
924 	offset = sizeof(struct smb_ntsd);
925 	pntsd->sacloffset = 0;
926 	pntsd->revision = cpu_to_le16(1);
927 	pntsd->type = cpu_to_le16(SELF_RELATIVE);
928 	if (ppntsd)
929 		pntsd->type |= ppntsd->type;
930 
931 	if (addition_info & OWNER_SECINFO) {
932 		pntsd->osidoffset = cpu_to_le32(offset);
933 		owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
934 		smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
935 		offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
936 	}
937 
938 	if (addition_info & GROUP_SECINFO) {
939 		pntsd->gsidoffset = cpu_to_le32(offset);
940 		group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
941 		smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
942 		offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
943 	}
944 
945 	if (addition_info & DACL_SECINFO) {
946 		pntsd->type |= cpu_to_le16(DACL_PRESENT);
947 		dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
948 		dacl_ptr->revision = cpu_to_le16(2);
949 		dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
950 		dacl_ptr->num_aces = 0;
951 
952 		if (!ppntsd) {
953 			set_mode_dacl(idmap, dacl_ptr, fattr);
954 		} else {
955 			struct smb_acl *ppdacl_ptr;
956 			unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
957 			int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
958 
959 			if (!dacl_offset ||
960 			    (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
961 				goto out;
962 
963 			ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
964 			ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
965 			if (ppdacl_size > ntacl_size ||
966 			    ppdacl_size < sizeof(struct smb_acl))
967 				goto out;
968 
969 			set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr,
970 				       ntacl_size - sizeof(struct smb_acl),
971 				       nowner_sid_ptr, ngroup_sid_ptr,
972 				       fattr);
973 		}
974 		pntsd->dacloffset = cpu_to_le32(offset);
975 		offset += le16_to_cpu(dacl_ptr->size);
976 	}
977 
978 out:
979 	kfree(nowner_sid_ptr);
980 	kfree(ngroup_sid_ptr);
981 	*secdesclen = offset;
982 	return rc;
983 }
984 
985 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
986 			u8 flags, __le32 access_req)
987 {
988 	ace->type = type;
989 	ace->flags = flags;
990 	ace->access_req = access_req;
991 	smb_copy_sid(&ace->sid, sid);
992 	ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
993 }
994 
995 int smb_inherit_dacl(struct ksmbd_conn *conn,
996 		     const struct path *path,
997 		     unsigned int uid, unsigned int gid)
998 {
999 	const struct smb_sid *psid, *creator = NULL;
1000 	struct smb_ace *parent_aces, *aces;
1001 	struct smb_acl *parent_pdacl;
1002 	struct smb_ntsd *parent_pntsd = NULL;
1003 	struct smb_sid owner_sid, group_sid;
1004 	struct dentry *parent = path->dentry->d_parent;
1005 	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1006 	int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
1007 	int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
1008 	char *aces_base;
1009 	bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
1010 
1011 	pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1012 					    parent, &parent_pntsd);
1013 	if (pntsd_size <= 0)
1014 		return -ENOENT;
1015 	dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
1016 	if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
1017 		rc = -EINVAL;
1018 		goto free_parent_pntsd;
1019 	}
1020 
1021 	parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
1022 	acl_len = pntsd_size - dacloffset;
1023 	num_aces = le32_to_cpu(parent_pdacl->num_aces);
1024 	pntsd_type = le16_to_cpu(parent_pntsd->type);
1025 	pdacl_size = le16_to_cpu(parent_pdacl->size);
1026 
1027 	if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
1028 		rc = -EINVAL;
1029 		goto free_parent_pntsd;
1030 	}
1031 
1032 	aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1033 	if (!aces_base) {
1034 		rc = -ENOMEM;
1035 		goto free_parent_pntsd;
1036 	}
1037 
1038 	aces = (struct smb_ace *)aces_base;
1039 	parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1040 			sizeof(struct smb_acl));
1041 	aces_size = acl_len - sizeof(struct smb_acl);
1042 
1043 	if (pntsd_type & DACL_AUTO_INHERITED)
1044 		inherited_flags = INHERITED_ACE;
1045 
1046 	for (i = 0; i < num_aces; i++) {
1047 		int pace_size;
1048 
1049 		if (offsetof(struct smb_ace, access_req) > aces_size)
1050 			break;
1051 
1052 		pace_size = le16_to_cpu(parent_aces->size);
1053 		if (pace_size > aces_size)
1054 			break;
1055 
1056 		aces_size -= pace_size;
1057 
1058 		flags = parent_aces->flags;
1059 		if (!smb_inherit_flags(flags, is_dir))
1060 			goto pass;
1061 		if (is_dir) {
1062 			flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1063 			if (!(flags & CONTAINER_INHERIT_ACE))
1064 				flags |= INHERIT_ONLY_ACE;
1065 			if (flags & NO_PROPAGATE_INHERIT_ACE)
1066 				flags = 0;
1067 		} else {
1068 			flags = 0;
1069 		}
1070 
1071 		if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1072 			creator = &creator_owner;
1073 			id_to_sid(uid, SIDOWNER, &owner_sid);
1074 			psid = &owner_sid;
1075 		} else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1076 			creator = &creator_group;
1077 			id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1078 			psid = &group_sid;
1079 		} else {
1080 			creator = NULL;
1081 			psid = &parent_aces->sid;
1082 		}
1083 
1084 		if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1085 			smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1086 				    parent_aces->access_req);
1087 			nt_size += le16_to_cpu(aces->size);
1088 			ace_cnt++;
1089 			aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1090 			flags |= INHERIT_ONLY_ACE;
1091 			psid = creator;
1092 		} else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1093 			psid = &parent_aces->sid;
1094 		}
1095 
1096 		smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1097 			    parent_aces->access_req);
1098 		nt_size += le16_to_cpu(aces->size);
1099 		aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1100 		ace_cnt++;
1101 pass:
1102 		parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
1103 	}
1104 
1105 	if (nt_size > 0) {
1106 		struct smb_ntsd *pntsd;
1107 		struct smb_acl *pdacl;
1108 		struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1109 		int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1110 		int pntsd_alloc_size;
1111 
1112 		if (parent_pntsd->osidoffset) {
1113 			powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1114 					le32_to_cpu(parent_pntsd->osidoffset));
1115 			powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1116 		}
1117 		if (parent_pntsd->gsidoffset) {
1118 			pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1119 					le32_to_cpu(parent_pntsd->gsidoffset));
1120 			pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1121 		}
1122 
1123 		pntsd_alloc_size = sizeof(struct smb_ntsd) + powner_sid_size +
1124 			pgroup_sid_size + sizeof(struct smb_acl) + nt_size;
1125 
1126 		pntsd = kzalloc(pntsd_alloc_size, GFP_KERNEL);
1127 		if (!pntsd) {
1128 			rc = -ENOMEM;
1129 			goto free_aces_base;
1130 		}
1131 
1132 		pntsd->revision = cpu_to_le16(1);
1133 		pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1134 		if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1135 			pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1136 		pntsd_size = sizeof(struct smb_ntsd);
1137 		pntsd->osidoffset = parent_pntsd->osidoffset;
1138 		pntsd->gsidoffset = parent_pntsd->gsidoffset;
1139 		pntsd->dacloffset = parent_pntsd->dacloffset;
1140 
1141 		if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size >
1142 		    pntsd_alloc_size) {
1143 			rc = -EINVAL;
1144 			kfree(pntsd);
1145 			goto free_aces_base;
1146 		}
1147 
1148 		if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size >
1149 		    pntsd_alloc_size) {
1150 			rc = -EINVAL;
1151 			kfree(pntsd);
1152 			goto free_aces_base;
1153 		}
1154 
1155 		if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size >
1156 		    pntsd_alloc_size) {
1157 			rc = -EINVAL;
1158 			kfree(pntsd);
1159 			goto free_aces_base;
1160 		}
1161 
1162 		if (pntsd->osidoffset) {
1163 			struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1164 					le32_to_cpu(pntsd->osidoffset));
1165 			memcpy(owner_sid, powner_sid, powner_sid_size);
1166 			pntsd_size += powner_sid_size;
1167 		}
1168 
1169 		if (pntsd->gsidoffset) {
1170 			struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1171 					le32_to_cpu(pntsd->gsidoffset));
1172 			memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1173 			pntsd_size += pgroup_sid_size;
1174 		}
1175 
1176 		if (pntsd->dacloffset) {
1177 			struct smb_ace *pace;
1178 
1179 			pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1180 			pdacl->revision = cpu_to_le16(2);
1181 			pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1182 			pdacl->num_aces = cpu_to_le32(ace_cnt);
1183 			pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1184 			memcpy(pace, aces_base, nt_size);
1185 			pntsd_size += sizeof(struct smb_acl) + nt_size;
1186 		}
1187 
1188 		ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size, false);
1189 		kfree(pntsd);
1190 	}
1191 
1192 free_aces_base:
1193 	kfree(aces_base);
1194 free_parent_pntsd:
1195 	kfree(parent_pntsd);
1196 	return rc;
1197 }
1198 
1199 bool smb_inherit_flags(int flags, bool is_dir)
1200 {
1201 	if (!is_dir)
1202 		return (flags & OBJECT_INHERIT_ACE) != 0;
1203 
1204 	if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1205 		return true;
1206 
1207 	if (flags & CONTAINER_INHERIT_ACE)
1208 		return true;
1209 	return false;
1210 }
1211 
1212 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
1213 			__le32 *pdaccess, int uid)
1214 {
1215 	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1216 	struct smb_ntsd *pntsd = NULL;
1217 	struct smb_acl *pdacl;
1218 	struct posix_acl *posix_acls;
1219 	int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
1220 	struct smb_sid sid;
1221 	int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1222 	struct smb_ace *ace;
1223 	int i, found = 0;
1224 	unsigned int access_bits = 0;
1225 	struct smb_ace *others_ace = NULL;
1226 	struct posix_acl_entry *pa_entry;
1227 	unsigned int sid_type = SIDOWNER;
1228 	unsigned short ace_size;
1229 
1230 	ksmbd_debug(SMB, "check permission using windows acl\n");
1231 	pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1232 					    path->dentry, &pntsd);
1233 	if (pntsd_size <= 0 || !pntsd)
1234 		goto err_out;
1235 
1236 	dacl_offset = le32_to_cpu(pntsd->dacloffset);
1237 	if (!dacl_offset ||
1238 	    (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
1239 		goto err_out;
1240 
1241 	pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1242 	acl_size = pntsd_size - dacl_offset;
1243 	pdacl_size = le16_to_cpu(pdacl->size);
1244 
1245 	if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
1246 		goto err_out;
1247 
1248 	if (!pdacl->num_aces) {
1249 		if (!(pdacl_size - sizeof(struct smb_acl)) &&
1250 		    *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1251 			rc = -EACCES;
1252 			goto err_out;
1253 		}
1254 		goto err_out;
1255 	}
1256 
1257 	if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1258 		granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1259 			DELETE;
1260 
1261 		ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1262 		aces_size = acl_size - sizeof(struct smb_acl);
1263 		for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1264 			if (offsetof(struct smb_ace, access_req) > aces_size)
1265 				break;
1266 			ace_size = le16_to_cpu(ace->size);
1267 			if (ace_size > aces_size)
1268 				break;
1269 			aces_size -= ace_size;
1270 			granted |= le32_to_cpu(ace->access_req);
1271 			ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1272 		}
1273 
1274 		if (!pdacl->num_aces)
1275 			granted = GENERIC_ALL_FLAGS;
1276 	}
1277 
1278 	if (!uid)
1279 		sid_type = SIDUNIX_USER;
1280 	id_to_sid(uid, sid_type, &sid);
1281 
1282 	ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1283 	aces_size = acl_size - sizeof(struct smb_acl);
1284 	for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1285 		if (offsetof(struct smb_ace, access_req) > aces_size)
1286 			break;
1287 		ace_size = le16_to_cpu(ace->size);
1288 		if (ace_size > aces_size)
1289 			break;
1290 		aces_size -= ace_size;
1291 
1292 		if (!compare_sids(&sid, &ace->sid) ||
1293 		    !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1294 			found = 1;
1295 			break;
1296 		}
1297 		if (!compare_sids(&sid_everyone, &ace->sid))
1298 			others_ace = ace;
1299 
1300 		ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1301 	}
1302 
1303 	if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1304 		granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1305 			DELETE;
1306 
1307 		granted |= le32_to_cpu(ace->access_req);
1308 
1309 		if (!pdacl->num_aces)
1310 			granted = GENERIC_ALL_FLAGS;
1311 	}
1312 
1313 	if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1314 		posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1315 		if (!IS_ERR_OR_NULL(posix_acls) && !found) {
1316 			unsigned int id = -1;
1317 
1318 			pa_entry = posix_acls->a_entries;
1319 			for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1320 				if (pa_entry->e_tag == ACL_USER)
1321 					id = posix_acl_uid_translate(idmap, pa_entry);
1322 				else if (pa_entry->e_tag == ACL_GROUP)
1323 					id = posix_acl_gid_translate(idmap, pa_entry);
1324 				else
1325 					continue;
1326 
1327 				if (id == uid) {
1328 					mode_to_access_flags(pa_entry->e_perm,
1329 							     0777,
1330 							     &access_bits);
1331 					if (!access_bits)
1332 						access_bits =
1333 							SET_MINIMUM_RIGHTS;
1334 					posix_acl_release(posix_acls);
1335 					goto check_access_bits;
1336 				}
1337 			}
1338 		}
1339 		if (!IS_ERR_OR_NULL(posix_acls))
1340 			posix_acl_release(posix_acls);
1341 	}
1342 
1343 	if (!found) {
1344 		if (others_ace) {
1345 			ace = others_ace;
1346 		} else {
1347 			ksmbd_debug(SMB, "Can't find corresponding sid\n");
1348 			rc = -EACCES;
1349 			goto err_out;
1350 		}
1351 	}
1352 
1353 	switch (ace->type) {
1354 	case ACCESS_ALLOWED_ACE_TYPE:
1355 		access_bits = le32_to_cpu(ace->access_req);
1356 		break;
1357 	case ACCESS_DENIED_ACE_TYPE:
1358 	case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1359 		access_bits = le32_to_cpu(~ace->access_req);
1360 		break;
1361 	}
1362 
1363 check_access_bits:
1364 	if (granted &
1365 	    ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1366 		ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1367 			    granted, le32_to_cpu(ace->access_req));
1368 		rc = -EACCES;
1369 		goto err_out;
1370 	}
1371 
1372 	*pdaccess = cpu_to_le32(granted);
1373 err_out:
1374 	kfree(pntsd);
1375 	return rc;
1376 }
1377 
1378 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1379 		 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1380 		 bool type_check, bool get_write)
1381 {
1382 	int rc;
1383 	struct smb_fattr fattr = {{0}};
1384 	struct inode *inode = d_inode(path->dentry);
1385 	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1386 	struct iattr newattrs;
1387 
1388 	fattr.cf_uid = INVALID_UID;
1389 	fattr.cf_gid = INVALID_GID;
1390 	fattr.cf_mode = inode->i_mode;
1391 
1392 	rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr);
1393 	if (rc)
1394 		goto out;
1395 
1396 	newattrs.ia_valid = ATTR_CTIME;
1397 	if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1398 		newattrs.ia_valid |= ATTR_UID;
1399 		newattrs.ia_uid = fattr.cf_uid;
1400 	}
1401 	if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1402 		newattrs.ia_valid |= ATTR_GID;
1403 		newattrs.ia_gid = fattr.cf_gid;
1404 	}
1405 	newattrs.ia_valid |= ATTR_MODE;
1406 	newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1407 
1408 	ksmbd_vfs_remove_acl_xattrs(idmap, path);
1409 	/* Update posix acls */
1410 	if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1411 		rc = set_posix_acl(idmap, path->dentry,
1412 				   ACL_TYPE_ACCESS, fattr.cf_acls);
1413 		if (rc < 0)
1414 			ksmbd_debug(SMB,
1415 				    "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1416 				    rc);
1417 		if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1418 			rc = set_posix_acl(idmap, path->dentry,
1419 					   ACL_TYPE_DEFAULT, fattr.cf_dacls);
1420 			if (rc)
1421 				ksmbd_debug(SMB,
1422 					    "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1423 					    rc);
1424 		}
1425 	}
1426 
1427 	inode_lock(inode);
1428 	rc = notify_change(idmap, path->dentry, &newattrs, NULL);
1429 	inode_unlock(inode);
1430 	if (rc)
1431 		goto out;
1432 
1433 	/* Check it only calling from SD BUFFER context */
1434 	if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1435 		goto out;
1436 
1437 	if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1438 		/* Update WinACL in xattr */
1439 		ksmbd_vfs_remove_sd_xattrs(idmap, path);
1440 		ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len,
1441 				get_write);
1442 	}
1443 
1444 out:
1445 	posix_acl_release(fattr.cf_acls);
1446 	posix_acl_release(fattr.cf_dacls);
1447 	return rc;
1448 }
1449 
1450 void ksmbd_init_domain(u32 *sub_auth)
1451 {
1452 	int i;
1453 
1454 	memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1455 	for (i = 0; i < 3; ++i)
1456 		server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);
1457 }
1458