xref: /linux/fs/smb/server/smbacl.c (revision dbcedec3a31119d7594baacc743300d127c99c56)
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 	ret = init_acl_state(&acl_state, num_aces);
405 	if (ret)
406 		return;
407 	ret = init_acl_state(&default_acl_state, num_aces);
408 	if (ret) {
409 		free_acl_state(&acl_state);
410 		return;
411 	}
412 
413 	ppace = kmalloc_array(num_aces, sizeof(struct smb_ace *), GFP_KERNEL);
414 	if (!ppace) {
415 		free_acl_state(&default_acl_state);
416 		free_acl_state(&acl_state);
417 		return;
418 	}
419 
420 	/*
421 	 * reset rwx permissions for user/group/other.
422 	 * Also, if num_aces is 0 i.e. DACL has no ACEs,
423 	 * user/group/other have no permissions
424 	 */
425 	for (i = 0; i < num_aces; ++i) {
426 		if (end_of_acl - acl_base < acl_size)
427 			break;
428 
429 		ppace[i] = (struct smb_ace *)(acl_base + acl_size);
430 		acl_base = (char *)ppace[i];
431 		acl_size = offsetof(struct smb_ace, sid) +
432 			offsetof(struct smb_sid, sub_auth);
433 
434 		if (end_of_acl - acl_base < acl_size ||
435 		    ppace[i]->sid.num_subauth > SID_MAX_SUB_AUTHORITIES ||
436 		    (end_of_acl - acl_base <
437 		     acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth) ||
438 		    (le16_to_cpu(ppace[i]->size) <
439 		     acl_size + sizeof(__le32) * ppace[i]->sid.num_subauth))
440 			break;
441 
442 		acl_size = le16_to_cpu(ppace[i]->size);
443 		ppace[i]->access_req =
444 			smb_map_generic_desired_access(ppace[i]->access_req);
445 
446 		if (!(compare_sids(&ppace[i]->sid, &sid_unix_NFS_mode))) {
447 			fattr->cf_mode =
448 				le32_to_cpu(ppace[i]->sid.sub_auth[2]);
449 			break;
450 		} else if (!compare_sids(&ppace[i]->sid, pownersid)) {
451 			acl_mode = access_flags_to_mode(fattr,
452 							ppace[i]->access_req,
453 							ppace[i]->type);
454 			acl_mode &= 0700;
455 
456 			if (!owner_found) {
457 				mode &= ~(0700);
458 				mode |= acl_mode;
459 			}
460 			owner_found = true;
461 		} else if (!compare_sids(&ppace[i]->sid, pgrpsid) ||
462 			   ppace[i]->sid.sub_auth[ppace[i]->sid.num_subauth - 1] ==
463 			    DOMAIN_USER_RID_LE) {
464 			acl_mode = access_flags_to_mode(fattr,
465 							ppace[i]->access_req,
466 							ppace[i]->type);
467 			acl_mode &= 0070;
468 			if (!group_found) {
469 				mode &= ~(0070);
470 				mode |= acl_mode;
471 			}
472 			group_found = true;
473 		} else if (!compare_sids(&ppace[i]->sid, &sid_everyone)) {
474 			acl_mode = access_flags_to_mode(fattr,
475 							ppace[i]->access_req,
476 							ppace[i]->type);
477 			acl_mode &= 0007;
478 			if (!others_found) {
479 				mode &= ~(0007);
480 				mode |= acl_mode;
481 			}
482 			others_found = true;
483 		} else if (!compare_sids(&ppace[i]->sid, &creator_owner)) {
484 			continue;
485 		} else if (!compare_sids(&ppace[i]->sid, &creator_group)) {
486 			continue;
487 		} else if (!compare_sids(&ppace[i]->sid, &sid_authusers)) {
488 			continue;
489 		} else {
490 			struct smb_fattr temp_fattr;
491 
492 			acl_mode = access_flags_to_mode(fattr, ppace[i]->access_req,
493 							ppace[i]->type);
494 			temp_fattr.cf_uid = INVALID_UID;
495 			ret = sid_to_id(idmap, &ppace[i]->sid, SIDOWNER, &temp_fattr);
496 			if (ret || uid_eq(temp_fattr.cf_uid, INVALID_UID)) {
497 				pr_err("%s: Error %d mapping Owner SID to uid\n",
498 				       __func__, ret);
499 				continue;
500 			}
501 
502 			acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
503 			acl_state.users->aces[acl_state.users->n].uid =
504 				temp_fattr.cf_uid;
505 			acl_state.users->aces[acl_state.users->n++].perms.allow =
506 				((acl_mode & 0700) >> 6) | 0004;
507 			default_acl_state.owner.allow = ((acl_mode & 0700) >> 6) | 0004;
508 			default_acl_state.users->aces[default_acl_state.users->n].uid =
509 				temp_fattr.cf_uid;
510 			default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
511 				((acl_mode & 0700) >> 6) | 0004;
512 		}
513 	}
514 	kfree(ppace);
515 
516 	if (owner_found) {
517 		/* The owner must be set to at least read-only. */
518 		acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
519 		acl_state.users->aces[acl_state.users->n].uid = fattr->cf_uid;
520 		acl_state.users->aces[acl_state.users->n++].perms.allow =
521 			((mode & 0700) >> 6) | 0004;
522 		default_acl_state.owner.allow = ((mode & 0700) >> 6) | 0004;
523 		default_acl_state.users->aces[default_acl_state.users->n].uid =
524 			fattr->cf_uid;
525 		default_acl_state.users->aces[default_acl_state.users->n++].perms.allow =
526 			((mode & 0700) >> 6) | 0004;
527 	}
528 
529 	if (group_found) {
530 		acl_state.group.allow = (mode & 0070) >> 3;
531 		acl_state.groups->aces[acl_state.groups->n].gid =
532 			fattr->cf_gid;
533 		acl_state.groups->aces[acl_state.groups->n++].perms.allow =
534 			(mode & 0070) >> 3;
535 		default_acl_state.group.allow = (mode & 0070) >> 3;
536 		default_acl_state.groups->aces[default_acl_state.groups->n].gid =
537 			fattr->cf_gid;
538 		default_acl_state.groups->aces[default_acl_state.groups->n++].perms.allow =
539 			(mode & 0070) >> 3;
540 	}
541 
542 	if (others_found) {
543 		fattr->cf_mode &= ~(0007);
544 		fattr->cf_mode |= mode & 0007;
545 
546 		acl_state.other.allow = mode & 0007;
547 		default_acl_state.other.allow = mode & 0007;
548 	}
549 
550 	if (acl_state.users->n || acl_state.groups->n) {
551 		acl_state.mask.allow = 0x07;
552 
553 		if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
554 			fattr->cf_acls =
555 				posix_acl_alloc(acl_state.users->n +
556 					acl_state.groups->n + 4, GFP_KERNEL);
557 			if (fattr->cf_acls) {
558 				cf_pace = fattr->cf_acls->a_entries;
559 				posix_state_to_acl(&acl_state, cf_pace);
560 			}
561 		}
562 	}
563 
564 	if (default_acl_state.users->n || default_acl_state.groups->n) {
565 		default_acl_state.mask.allow = 0x07;
566 
567 		if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
568 			fattr->cf_dacls =
569 				posix_acl_alloc(default_acl_state.users->n +
570 				default_acl_state.groups->n + 4, GFP_KERNEL);
571 			if (fattr->cf_dacls) {
572 				cf_pdace = fattr->cf_dacls->a_entries;
573 				posix_state_to_acl(&default_acl_state, cf_pdace);
574 			}
575 		}
576 	}
577 	free_acl_state(&acl_state);
578 	free_acl_state(&default_acl_state);
579 }
580 
581 static void set_posix_acl_entries_dacl(struct mnt_idmap *idmap,
582 				       struct smb_ace *pndace,
583 				       struct smb_fattr *fattr, u32 *num_aces,
584 				       u16 *size, u32 nt_aces_num)
585 {
586 	struct posix_acl_entry *pace;
587 	struct smb_sid *sid;
588 	struct smb_ace *ntace;
589 	int i, j;
590 
591 	if (!fattr->cf_acls)
592 		goto posix_default_acl;
593 
594 	pace = fattr->cf_acls->a_entries;
595 	for (i = 0; i < fattr->cf_acls->a_count; i++, pace++) {
596 		int flags = 0;
597 
598 		sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
599 		if (!sid)
600 			break;
601 
602 		if (pace->e_tag == ACL_USER) {
603 			uid_t uid;
604 			unsigned int sid_type = SIDOWNER;
605 
606 			uid = posix_acl_uid_translate(idmap, pace);
607 			if (!uid)
608 				sid_type = SIDUNIX_USER;
609 			id_to_sid(uid, sid_type, sid);
610 		} else if (pace->e_tag == ACL_GROUP) {
611 			gid_t gid;
612 
613 			gid = posix_acl_gid_translate(idmap, pace);
614 			id_to_sid(gid, SIDUNIX_GROUP, sid);
615 		} else if (pace->e_tag == ACL_OTHER && !nt_aces_num) {
616 			smb_copy_sid(sid, &sid_everyone);
617 		} else {
618 			kfree(sid);
619 			continue;
620 		}
621 		ntace = pndace;
622 		for (j = 0; j < nt_aces_num; j++) {
623 			if (ntace->sid.sub_auth[ntace->sid.num_subauth - 1] ==
624 					sid->sub_auth[sid->num_subauth - 1])
625 				goto pass_same_sid;
626 			ntace = (struct smb_ace *)((char *)ntace +
627 					le16_to_cpu(ntace->size));
628 		}
629 
630 		if (S_ISDIR(fattr->cf_mode) && pace->e_tag == ACL_OTHER)
631 			flags = 0x03;
632 
633 		ntace = (struct smb_ace *)((char *)pndace + *size);
634 		*size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, flags,
635 				pace->e_perm, 0777);
636 		(*num_aces)++;
637 		if (pace->e_tag == ACL_USER)
638 			ntace->access_req |=
639 				FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
640 
641 		if (S_ISDIR(fattr->cf_mode) &&
642 		    (pace->e_tag == ACL_USER || pace->e_tag == ACL_GROUP)) {
643 			ntace = (struct smb_ace *)((char *)pndace + *size);
644 			*size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED,
645 					0x03, pace->e_perm, 0777);
646 			(*num_aces)++;
647 			if (pace->e_tag == ACL_USER)
648 				ntace->access_req |=
649 					FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
650 		}
651 
652 pass_same_sid:
653 		kfree(sid);
654 	}
655 
656 	if (nt_aces_num)
657 		return;
658 
659 posix_default_acl:
660 	if (!fattr->cf_dacls)
661 		return;
662 
663 	pace = fattr->cf_dacls->a_entries;
664 	for (i = 0; i < fattr->cf_dacls->a_count; i++, pace++) {
665 		sid = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
666 		if (!sid)
667 			break;
668 
669 		if (pace->e_tag == ACL_USER) {
670 			uid_t uid;
671 
672 			uid = posix_acl_uid_translate(idmap, pace);
673 			id_to_sid(uid, SIDCREATOR_OWNER, sid);
674 		} else if (pace->e_tag == ACL_GROUP) {
675 			gid_t gid;
676 
677 			gid = posix_acl_gid_translate(idmap, pace);
678 			id_to_sid(gid, SIDCREATOR_GROUP, sid);
679 		} else {
680 			kfree(sid);
681 			continue;
682 		}
683 
684 		ntace = (struct smb_ace *)((char *)pndace + *size);
685 		*size += fill_ace_for_sid(ntace, sid, ACCESS_ALLOWED, 0x0b,
686 				pace->e_perm, 0777);
687 		(*num_aces)++;
688 		if (pace->e_tag == ACL_USER)
689 			ntace->access_req |=
690 				FILE_DELETE_LE | FILE_DELETE_CHILD_LE;
691 		kfree(sid);
692 	}
693 }
694 
695 static void set_ntacl_dacl(struct mnt_idmap *idmap,
696 			   struct smb_acl *pndacl,
697 			   struct smb_acl *nt_dacl,
698 			   unsigned int aces_size,
699 			   const struct smb_sid *pownersid,
700 			   const struct smb_sid *pgrpsid,
701 			   struct smb_fattr *fattr)
702 {
703 	struct smb_ace *ntace, *pndace;
704 	int nt_num_aces = le32_to_cpu(nt_dacl->num_aces), num_aces = 0;
705 	unsigned short size = 0;
706 	int i;
707 
708 	pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
709 	if (nt_num_aces) {
710 		ntace = (struct smb_ace *)((char *)nt_dacl + sizeof(struct smb_acl));
711 		for (i = 0; i < nt_num_aces; i++) {
712 			unsigned short nt_ace_size;
713 
714 			if (offsetof(struct smb_ace, access_req) > aces_size)
715 				break;
716 
717 			nt_ace_size = le16_to_cpu(ntace->size);
718 			if (nt_ace_size > aces_size)
719 				break;
720 
721 			memcpy((char *)pndace + size, ntace, nt_ace_size);
722 			size += nt_ace_size;
723 			aces_size -= nt_ace_size;
724 			ntace = (struct smb_ace *)((char *)ntace + nt_ace_size);
725 			num_aces++;
726 		}
727 	}
728 
729 	set_posix_acl_entries_dacl(idmap, pndace, fattr,
730 				   &num_aces, &size, nt_num_aces);
731 	pndacl->num_aces = cpu_to_le32(num_aces);
732 	pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
733 }
734 
735 static void set_mode_dacl(struct mnt_idmap *idmap,
736 			  struct smb_acl *pndacl, struct smb_fattr *fattr)
737 {
738 	struct smb_ace *pace, *pndace;
739 	u32 num_aces = 0;
740 	u16 size = 0, ace_size = 0;
741 	uid_t uid;
742 	const struct smb_sid *sid;
743 
744 	pace = pndace = (struct smb_ace *)((char *)pndacl + sizeof(struct smb_acl));
745 
746 	if (fattr->cf_acls) {
747 		set_posix_acl_entries_dacl(idmap, pndace, fattr,
748 					   &num_aces, &size, num_aces);
749 		goto out;
750 	}
751 
752 	/* owner RID */
753 	uid = from_kuid(&init_user_ns, fattr->cf_uid);
754 	if (uid)
755 		sid = &server_conf.domain_sid;
756 	else
757 		sid = &sid_unix_users;
758 	ace_size = fill_ace_for_sid(pace, sid, ACCESS_ALLOWED, 0,
759 				    fattr->cf_mode, 0700);
760 	pace->sid.sub_auth[pace->sid.num_subauth++] = cpu_to_le32(uid);
761 	pace->size = cpu_to_le16(ace_size + 4);
762 	size += le16_to_cpu(pace->size);
763 	pace = (struct smb_ace *)((char *)pndace + size);
764 
765 	/* Group RID */
766 	ace_size = fill_ace_for_sid(pace, &sid_unix_groups,
767 				    ACCESS_ALLOWED, 0, fattr->cf_mode, 0070);
768 	pace->sid.sub_auth[pace->sid.num_subauth++] =
769 		cpu_to_le32(from_kgid(&init_user_ns, fattr->cf_gid));
770 	pace->size = cpu_to_le16(ace_size + 4);
771 	size += le16_to_cpu(pace->size);
772 	pace = (struct smb_ace *)((char *)pndace + size);
773 	num_aces = 3;
774 
775 	if (S_ISDIR(fattr->cf_mode)) {
776 		pace = (struct smb_ace *)((char *)pndace + size);
777 
778 		/* creator owner */
779 		size += fill_ace_for_sid(pace, &creator_owner, ACCESS_ALLOWED,
780 					 0x0b, fattr->cf_mode, 0700);
781 		pace = (struct smb_ace *)((char *)pndace + size);
782 
783 		/* creator group */
784 		size += fill_ace_for_sid(pace, &creator_group, ACCESS_ALLOWED,
785 					 0x0b, fattr->cf_mode, 0070);
786 		pace = (struct smb_ace *)((char *)pndace + size);
787 		num_aces = 5;
788 	}
789 
790 	/* other */
791 	size += fill_ace_for_sid(pace, &sid_everyone, ACCESS_ALLOWED, 0,
792 				 fattr->cf_mode, 0007);
793 
794 out:
795 	pndacl->num_aces = cpu_to_le32(num_aces);
796 	pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);
797 }
798 
799 static int parse_sid(struct smb_sid *psid, char *end_of_acl)
800 {
801 	/*
802 	 * validate that we do not go past end of ACL - sid must be at least 8
803 	 * bytes long (assuming no sub-auths - e.g. the null SID
804 	 */
805 	if (end_of_acl < (char *)psid + 8) {
806 		pr_err("ACL too small to parse SID %p\n", psid);
807 		return -EINVAL;
808 	}
809 
810 	return 0;
811 }
812 
813 /* Convert CIFS ACL to POSIX form */
814 int parse_sec_desc(struct mnt_idmap *idmap, struct smb_ntsd *pntsd,
815 		   int acl_len, struct smb_fattr *fattr)
816 {
817 	int rc = 0;
818 	struct smb_sid *owner_sid_ptr, *group_sid_ptr;
819 	struct smb_acl *dacl_ptr; /* no need for SACL ptr */
820 	char *end_of_acl = ((char *)pntsd) + acl_len;
821 	__u32 dacloffset;
822 	int pntsd_type;
823 
824 	if (!pntsd)
825 		return -EIO;
826 
827 	if (acl_len < sizeof(struct smb_ntsd))
828 		return -EINVAL;
829 
830 	owner_sid_ptr = (struct smb_sid *)((char *)pntsd +
831 			le32_to_cpu(pntsd->osidoffset));
832 	group_sid_ptr = (struct smb_sid *)((char *)pntsd +
833 			le32_to_cpu(pntsd->gsidoffset));
834 	dacloffset = le32_to_cpu(pntsd->dacloffset);
835 	dacl_ptr = (struct smb_acl *)((char *)pntsd + dacloffset);
836 	ksmbd_debug(SMB,
837 		    "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
838 		    pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
839 		    le32_to_cpu(pntsd->gsidoffset),
840 		    le32_to_cpu(pntsd->sacloffset), dacloffset);
841 
842 	pntsd_type = le16_to_cpu(pntsd->type);
843 	if (!(pntsd_type & DACL_PRESENT)) {
844 		ksmbd_debug(SMB, "DACL_PRESENT in DACL type is not set\n");
845 		return rc;
846 	}
847 
848 	pntsd->type = cpu_to_le16(DACL_PRESENT);
849 
850 	if (pntsd->osidoffset) {
851 		rc = parse_sid(owner_sid_ptr, end_of_acl);
852 		if (rc) {
853 			pr_err("%s: Error %d parsing Owner SID\n", __func__, rc);
854 			return rc;
855 		}
856 
857 		rc = sid_to_id(idmap, owner_sid_ptr, SIDOWNER, fattr);
858 		if (rc) {
859 			pr_err("%s: Error %d mapping Owner SID to uid\n",
860 			       __func__, rc);
861 			owner_sid_ptr = NULL;
862 		}
863 	}
864 
865 	if (pntsd->gsidoffset) {
866 		rc = parse_sid(group_sid_ptr, end_of_acl);
867 		if (rc) {
868 			pr_err("%s: Error %d mapping Owner SID to gid\n",
869 			       __func__, rc);
870 			return rc;
871 		}
872 		rc = sid_to_id(idmap, group_sid_ptr, SIDUNIX_GROUP, fattr);
873 		if (rc) {
874 			pr_err("%s: Error %d mapping Group SID to gid\n",
875 			       __func__, rc);
876 			group_sid_ptr = NULL;
877 		}
878 	}
879 
880 	if ((pntsd_type & (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ)) ==
881 	    (DACL_AUTO_INHERITED | DACL_AUTO_INHERIT_REQ))
882 		pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
883 	if (pntsd_type & DACL_PROTECTED)
884 		pntsd->type |= cpu_to_le16(DACL_PROTECTED);
885 
886 	if (dacloffset) {
887 		parse_dacl(idmap, dacl_ptr, end_of_acl,
888 			   owner_sid_ptr, group_sid_ptr, fattr);
889 	}
890 
891 	return 0;
892 }
893 
894 /* Convert permission bits from mode to equivalent CIFS ACL */
895 int build_sec_desc(struct mnt_idmap *idmap,
896 		   struct smb_ntsd *pntsd, struct smb_ntsd *ppntsd,
897 		   int ppntsd_size, int addition_info, __u32 *secdesclen,
898 		   struct smb_fattr *fattr)
899 {
900 	int rc = 0;
901 	__u32 offset;
902 	struct smb_sid *owner_sid_ptr, *group_sid_ptr;
903 	struct smb_sid *nowner_sid_ptr, *ngroup_sid_ptr;
904 	struct smb_acl *dacl_ptr = NULL; /* no need for SACL ptr */
905 	uid_t uid;
906 	gid_t gid;
907 	unsigned int sid_type = SIDOWNER;
908 
909 	nowner_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
910 	if (!nowner_sid_ptr)
911 		return -ENOMEM;
912 
913 	uid = from_kuid(&init_user_ns, fattr->cf_uid);
914 	if (!uid)
915 		sid_type = SIDUNIX_USER;
916 	id_to_sid(uid, sid_type, nowner_sid_ptr);
917 
918 	ngroup_sid_ptr = kmalloc(sizeof(struct smb_sid), GFP_KERNEL);
919 	if (!ngroup_sid_ptr) {
920 		kfree(nowner_sid_ptr);
921 		return -ENOMEM;
922 	}
923 
924 	gid = from_kgid(&init_user_ns, fattr->cf_gid);
925 	id_to_sid(gid, SIDUNIX_GROUP, ngroup_sid_ptr);
926 
927 	offset = sizeof(struct smb_ntsd);
928 	pntsd->sacloffset = 0;
929 	pntsd->revision = cpu_to_le16(1);
930 	pntsd->type = cpu_to_le16(SELF_RELATIVE);
931 	if (ppntsd)
932 		pntsd->type |= ppntsd->type;
933 
934 	if (addition_info & OWNER_SECINFO) {
935 		pntsd->osidoffset = cpu_to_le32(offset);
936 		owner_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
937 		smb_copy_sid(owner_sid_ptr, nowner_sid_ptr);
938 		offset += 1 + 1 + 6 + (nowner_sid_ptr->num_subauth * 4);
939 	}
940 
941 	if (addition_info & GROUP_SECINFO) {
942 		pntsd->gsidoffset = cpu_to_le32(offset);
943 		group_sid_ptr = (struct smb_sid *)((char *)pntsd + offset);
944 		smb_copy_sid(group_sid_ptr, ngroup_sid_ptr);
945 		offset += 1 + 1 + 6 + (ngroup_sid_ptr->num_subauth * 4);
946 	}
947 
948 	if (addition_info & DACL_SECINFO) {
949 		pntsd->type |= cpu_to_le16(DACL_PRESENT);
950 		dacl_ptr = (struct smb_acl *)((char *)pntsd + offset);
951 		dacl_ptr->revision = cpu_to_le16(2);
952 		dacl_ptr->size = cpu_to_le16(sizeof(struct smb_acl));
953 		dacl_ptr->num_aces = 0;
954 
955 		if (!ppntsd) {
956 			set_mode_dacl(idmap, dacl_ptr, fattr);
957 		} else {
958 			struct smb_acl *ppdacl_ptr;
959 			unsigned int dacl_offset = le32_to_cpu(ppntsd->dacloffset);
960 			int ppdacl_size, ntacl_size = ppntsd_size - dacl_offset;
961 
962 			if (!dacl_offset ||
963 			    (dacl_offset + sizeof(struct smb_acl) > ppntsd_size))
964 				goto out;
965 
966 			ppdacl_ptr = (struct smb_acl *)((char *)ppntsd + dacl_offset);
967 			ppdacl_size = le16_to_cpu(ppdacl_ptr->size);
968 			if (ppdacl_size > ntacl_size ||
969 			    ppdacl_size < sizeof(struct smb_acl))
970 				goto out;
971 
972 			set_ntacl_dacl(idmap, dacl_ptr, ppdacl_ptr,
973 				       ntacl_size - sizeof(struct smb_acl),
974 				       nowner_sid_ptr, ngroup_sid_ptr,
975 				       fattr);
976 		}
977 		pntsd->dacloffset = cpu_to_le32(offset);
978 		offset += le16_to_cpu(dacl_ptr->size);
979 	}
980 
981 out:
982 	kfree(nowner_sid_ptr);
983 	kfree(ngroup_sid_ptr);
984 	*secdesclen = offset;
985 	return rc;
986 }
987 
988 static void smb_set_ace(struct smb_ace *ace, const struct smb_sid *sid, u8 type,
989 			u8 flags, __le32 access_req)
990 {
991 	ace->type = type;
992 	ace->flags = flags;
993 	ace->access_req = access_req;
994 	smb_copy_sid(&ace->sid, sid);
995 	ace->size = cpu_to_le16(1 + 1 + 2 + 4 + 1 + 1 + 6 + (sid->num_subauth * 4));
996 }
997 
998 int smb_inherit_dacl(struct ksmbd_conn *conn,
999 		     const struct path *path,
1000 		     unsigned int uid, unsigned int gid)
1001 {
1002 	const struct smb_sid *psid, *creator = NULL;
1003 	struct smb_ace *parent_aces, *aces;
1004 	struct smb_acl *parent_pdacl;
1005 	struct smb_ntsd *parent_pntsd = NULL;
1006 	struct smb_sid owner_sid, group_sid;
1007 	struct dentry *parent = path->dentry->d_parent;
1008 	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1009 	int inherited_flags = 0, flags = 0, i, ace_cnt = 0, nt_size = 0, pdacl_size;
1010 	int rc = 0, num_aces, dacloffset, pntsd_type, pntsd_size, acl_len, aces_size;
1011 	char *aces_base;
1012 	bool is_dir = S_ISDIR(d_inode(path->dentry)->i_mode);
1013 
1014 	pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1015 					    parent, &parent_pntsd);
1016 	if (pntsd_size <= 0)
1017 		return -ENOENT;
1018 	dacloffset = le32_to_cpu(parent_pntsd->dacloffset);
1019 	if (!dacloffset || (dacloffset + sizeof(struct smb_acl) > pntsd_size)) {
1020 		rc = -EINVAL;
1021 		goto free_parent_pntsd;
1022 	}
1023 
1024 	parent_pdacl = (struct smb_acl *)((char *)parent_pntsd + dacloffset);
1025 	acl_len = pntsd_size - dacloffset;
1026 	num_aces = le32_to_cpu(parent_pdacl->num_aces);
1027 	pntsd_type = le16_to_cpu(parent_pntsd->type);
1028 	pdacl_size = le16_to_cpu(parent_pdacl->size);
1029 
1030 	if (pdacl_size > acl_len || pdacl_size < sizeof(struct smb_acl)) {
1031 		rc = -EINVAL;
1032 		goto free_parent_pntsd;
1033 	}
1034 
1035 	aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, GFP_KERNEL);
1036 	if (!aces_base) {
1037 		rc = -ENOMEM;
1038 		goto free_parent_pntsd;
1039 	}
1040 
1041 	aces = (struct smb_ace *)aces_base;
1042 	parent_aces = (struct smb_ace *)((char *)parent_pdacl +
1043 			sizeof(struct smb_acl));
1044 	aces_size = acl_len - sizeof(struct smb_acl);
1045 
1046 	if (pntsd_type & DACL_AUTO_INHERITED)
1047 		inherited_flags = INHERITED_ACE;
1048 
1049 	for (i = 0; i < num_aces; i++) {
1050 		int pace_size;
1051 
1052 		if (offsetof(struct smb_ace, access_req) > aces_size)
1053 			break;
1054 
1055 		pace_size = le16_to_cpu(parent_aces->size);
1056 		if (pace_size > aces_size)
1057 			break;
1058 
1059 		aces_size -= pace_size;
1060 
1061 		flags = parent_aces->flags;
1062 		if (!smb_inherit_flags(flags, is_dir))
1063 			goto pass;
1064 		if (is_dir) {
1065 			flags &= ~(INHERIT_ONLY_ACE | INHERITED_ACE);
1066 			if (!(flags & CONTAINER_INHERIT_ACE))
1067 				flags |= INHERIT_ONLY_ACE;
1068 			if (flags & NO_PROPAGATE_INHERIT_ACE)
1069 				flags = 0;
1070 		} else {
1071 			flags = 0;
1072 		}
1073 
1074 		if (!compare_sids(&creator_owner, &parent_aces->sid)) {
1075 			creator = &creator_owner;
1076 			id_to_sid(uid, SIDOWNER, &owner_sid);
1077 			psid = &owner_sid;
1078 		} else if (!compare_sids(&creator_group, &parent_aces->sid)) {
1079 			creator = &creator_group;
1080 			id_to_sid(gid, SIDUNIX_GROUP, &group_sid);
1081 			psid = &group_sid;
1082 		} else {
1083 			creator = NULL;
1084 			psid = &parent_aces->sid;
1085 		}
1086 
1087 		if (is_dir && creator && flags & CONTAINER_INHERIT_ACE) {
1088 			smb_set_ace(aces, psid, parent_aces->type, inherited_flags,
1089 				    parent_aces->access_req);
1090 			nt_size += le16_to_cpu(aces->size);
1091 			ace_cnt++;
1092 			aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1093 			flags |= INHERIT_ONLY_ACE;
1094 			psid = creator;
1095 		} else if (is_dir && !(parent_aces->flags & NO_PROPAGATE_INHERIT_ACE)) {
1096 			psid = &parent_aces->sid;
1097 		}
1098 
1099 		smb_set_ace(aces, psid, parent_aces->type, flags | inherited_flags,
1100 			    parent_aces->access_req);
1101 		nt_size += le16_to_cpu(aces->size);
1102 		aces = (struct smb_ace *)((char *)aces + le16_to_cpu(aces->size));
1103 		ace_cnt++;
1104 pass:
1105 		parent_aces = (struct smb_ace *)((char *)parent_aces + pace_size);
1106 	}
1107 
1108 	if (nt_size > 0) {
1109 		struct smb_ntsd *pntsd;
1110 		struct smb_acl *pdacl;
1111 		struct smb_sid *powner_sid = NULL, *pgroup_sid = NULL;
1112 		int powner_sid_size = 0, pgroup_sid_size = 0, pntsd_size;
1113 		int pntsd_alloc_size;
1114 
1115 		if (parent_pntsd->osidoffset) {
1116 			powner_sid = (struct smb_sid *)((char *)parent_pntsd +
1117 					le32_to_cpu(parent_pntsd->osidoffset));
1118 			powner_sid_size = 1 + 1 + 6 + (powner_sid->num_subauth * 4);
1119 		}
1120 		if (parent_pntsd->gsidoffset) {
1121 			pgroup_sid = (struct smb_sid *)((char *)parent_pntsd +
1122 					le32_to_cpu(parent_pntsd->gsidoffset));
1123 			pgroup_sid_size = 1 + 1 + 6 + (pgroup_sid->num_subauth * 4);
1124 		}
1125 
1126 		pntsd_alloc_size = sizeof(struct smb_ntsd) + powner_sid_size +
1127 			pgroup_sid_size + sizeof(struct smb_acl) + nt_size;
1128 
1129 		pntsd = kzalloc(pntsd_alloc_size, GFP_KERNEL);
1130 		if (!pntsd) {
1131 			rc = -ENOMEM;
1132 			goto free_aces_base;
1133 		}
1134 
1135 		pntsd->revision = cpu_to_le16(1);
1136 		pntsd->type = cpu_to_le16(SELF_RELATIVE | DACL_PRESENT);
1137 		if (le16_to_cpu(parent_pntsd->type) & DACL_AUTO_INHERITED)
1138 			pntsd->type |= cpu_to_le16(DACL_AUTO_INHERITED);
1139 		pntsd_size = sizeof(struct smb_ntsd);
1140 		pntsd->osidoffset = parent_pntsd->osidoffset;
1141 		pntsd->gsidoffset = parent_pntsd->gsidoffset;
1142 		pntsd->dacloffset = parent_pntsd->dacloffset;
1143 
1144 		if ((u64)le32_to_cpu(pntsd->osidoffset) + powner_sid_size >
1145 		    pntsd_alloc_size) {
1146 			rc = -EINVAL;
1147 			kfree(pntsd);
1148 			goto free_aces_base;
1149 		}
1150 
1151 		if ((u64)le32_to_cpu(pntsd->gsidoffset) + pgroup_sid_size >
1152 		    pntsd_alloc_size) {
1153 			rc = -EINVAL;
1154 			kfree(pntsd);
1155 			goto free_aces_base;
1156 		}
1157 
1158 		if ((u64)le32_to_cpu(pntsd->dacloffset) + sizeof(struct smb_acl) + nt_size >
1159 		    pntsd_alloc_size) {
1160 			rc = -EINVAL;
1161 			kfree(pntsd);
1162 			goto free_aces_base;
1163 		}
1164 
1165 		if (pntsd->osidoffset) {
1166 			struct smb_sid *owner_sid = (struct smb_sid *)((char *)pntsd +
1167 					le32_to_cpu(pntsd->osidoffset));
1168 			memcpy(owner_sid, powner_sid, powner_sid_size);
1169 			pntsd_size += powner_sid_size;
1170 		}
1171 
1172 		if (pntsd->gsidoffset) {
1173 			struct smb_sid *group_sid = (struct smb_sid *)((char *)pntsd +
1174 					le32_to_cpu(pntsd->gsidoffset));
1175 			memcpy(group_sid, pgroup_sid, pgroup_sid_size);
1176 			pntsd_size += pgroup_sid_size;
1177 		}
1178 
1179 		if (pntsd->dacloffset) {
1180 			struct smb_ace *pace;
1181 
1182 			pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1183 			pdacl->revision = cpu_to_le16(2);
1184 			pdacl->size = cpu_to_le16(sizeof(struct smb_acl) + nt_size);
1185 			pdacl->num_aces = cpu_to_le32(ace_cnt);
1186 			pace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1187 			memcpy(pace, aces_base, nt_size);
1188 			pntsd_size += sizeof(struct smb_acl) + nt_size;
1189 		}
1190 
1191 		ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, pntsd_size, false);
1192 		kfree(pntsd);
1193 	}
1194 
1195 free_aces_base:
1196 	kfree(aces_base);
1197 free_parent_pntsd:
1198 	kfree(parent_pntsd);
1199 	return rc;
1200 }
1201 
1202 bool smb_inherit_flags(int flags, bool is_dir)
1203 {
1204 	if (!is_dir)
1205 		return (flags & OBJECT_INHERIT_ACE) != 0;
1206 
1207 	if (flags & OBJECT_INHERIT_ACE && !(flags & NO_PROPAGATE_INHERIT_ACE))
1208 		return true;
1209 
1210 	if (flags & CONTAINER_INHERIT_ACE)
1211 		return true;
1212 	return false;
1213 }
1214 
1215 int smb_check_perm_dacl(struct ksmbd_conn *conn, const struct path *path,
1216 			__le32 *pdaccess, int uid)
1217 {
1218 	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1219 	struct smb_ntsd *pntsd = NULL;
1220 	struct smb_acl *pdacl;
1221 	struct posix_acl *posix_acls;
1222 	int rc = 0, pntsd_size, acl_size, aces_size, pdacl_size, dacl_offset;
1223 	struct smb_sid sid;
1224 	int granted = le32_to_cpu(*pdaccess & ~FILE_MAXIMAL_ACCESS_LE);
1225 	struct smb_ace *ace;
1226 	int i, found = 0;
1227 	unsigned int access_bits = 0;
1228 	struct smb_ace *others_ace = NULL;
1229 	struct posix_acl_entry *pa_entry;
1230 	unsigned int sid_type = SIDOWNER;
1231 	unsigned short ace_size;
1232 
1233 	ksmbd_debug(SMB, "check permission using windows acl\n");
1234 	pntsd_size = ksmbd_vfs_get_sd_xattr(conn, idmap,
1235 					    path->dentry, &pntsd);
1236 	if (pntsd_size <= 0 || !pntsd)
1237 		goto err_out;
1238 
1239 	dacl_offset = le32_to_cpu(pntsd->dacloffset);
1240 	if (!dacl_offset ||
1241 	    (dacl_offset + sizeof(struct smb_acl) > pntsd_size))
1242 		goto err_out;
1243 
1244 	pdacl = (struct smb_acl *)((char *)pntsd + le32_to_cpu(pntsd->dacloffset));
1245 	acl_size = pntsd_size - dacl_offset;
1246 	pdacl_size = le16_to_cpu(pdacl->size);
1247 
1248 	if (pdacl_size > acl_size || pdacl_size < sizeof(struct smb_acl))
1249 		goto err_out;
1250 
1251 	if (!pdacl->num_aces) {
1252 		if (!(pdacl_size - sizeof(struct smb_acl)) &&
1253 		    *pdaccess & ~(FILE_READ_CONTROL_LE | FILE_WRITE_DAC_LE)) {
1254 			rc = -EACCES;
1255 			goto err_out;
1256 		}
1257 		goto err_out;
1258 	}
1259 
1260 	if (*pdaccess & FILE_MAXIMAL_ACCESS_LE) {
1261 		granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1262 			DELETE;
1263 
1264 		ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1265 		aces_size = acl_size - sizeof(struct smb_acl);
1266 		for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1267 			if (offsetof(struct smb_ace, access_req) > aces_size)
1268 				break;
1269 			ace_size = le16_to_cpu(ace->size);
1270 			if (ace_size > aces_size)
1271 				break;
1272 			aces_size -= ace_size;
1273 			granted |= le32_to_cpu(ace->access_req);
1274 			ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1275 		}
1276 
1277 		if (!pdacl->num_aces)
1278 			granted = GENERIC_ALL_FLAGS;
1279 	}
1280 
1281 	if (!uid)
1282 		sid_type = SIDUNIX_USER;
1283 	id_to_sid(uid, sid_type, &sid);
1284 
1285 	ace = (struct smb_ace *)((char *)pdacl + sizeof(struct smb_acl));
1286 	aces_size = acl_size - sizeof(struct smb_acl);
1287 	for (i = 0; i < le32_to_cpu(pdacl->num_aces); i++) {
1288 		if (offsetof(struct smb_ace, access_req) > aces_size)
1289 			break;
1290 		ace_size = le16_to_cpu(ace->size);
1291 		if (ace_size > aces_size)
1292 			break;
1293 		aces_size -= ace_size;
1294 
1295 		if (!compare_sids(&sid, &ace->sid) ||
1296 		    !compare_sids(&sid_unix_NFS_mode, &ace->sid)) {
1297 			found = 1;
1298 			break;
1299 		}
1300 		if (!compare_sids(&sid_everyone, &ace->sid))
1301 			others_ace = ace;
1302 
1303 		ace = (struct smb_ace *)((char *)ace + le16_to_cpu(ace->size));
1304 	}
1305 
1306 	if (*pdaccess & FILE_MAXIMAL_ACCESS_LE && found) {
1307 		granted = READ_CONTROL | WRITE_DAC | FILE_READ_ATTRIBUTES |
1308 			DELETE;
1309 
1310 		granted |= le32_to_cpu(ace->access_req);
1311 
1312 		if (!pdacl->num_aces)
1313 			granted = GENERIC_ALL_FLAGS;
1314 	}
1315 
1316 	if (IS_ENABLED(CONFIG_FS_POSIX_ACL)) {
1317 		posix_acls = get_inode_acl(d_inode(path->dentry), ACL_TYPE_ACCESS);
1318 		if (!IS_ERR_OR_NULL(posix_acls) && !found) {
1319 			unsigned int id = -1;
1320 
1321 			pa_entry = posix_acls->a_entries;
1322 			for (i = 0; i < posix_acls->a_count; i++, pa_entry++) {
1323 				if (pa_entry->e_tag == ACL_USER)
1324 					id = posix_acl_uid_translate(idmap, pa_entry);
1325 				else if (pa_entry->e_tag == ACL_GROUP)
1326 					id = posix_acl_gid_translate(idmap, pa_entry);
1327 				else
1328 					continue;
1329 
1330 				if (id == uid) {
1331 					mode_to_access_flags(pa_entry->e_perm,
1332 							     0777,
1333 							     &access_bits);
1334 					if (!access_bits)
1335 						access_bits =
1336 							SET_MINIMUM_RIGHTS;
1337 					posix_acl_release(posix_acls);
1338 					goto check_access_bits;
1339 				}
1340 			}
1341 		}
1342 		if (!IS_ERR_OR_NULL(posix_acls))
1343 			posix_acl_release(posix_acls);
1344 	}
1345 
1346 	if (!found) {
1347 		if (others_ace) {
1348 			ace = others_ace;
1349 		} else {
1350 			ksmbd_debug(SMB, "Can't find corresponding sid\n");
1351 			rc = -EACCES;
1352 			goto err_out;
1353 		}
1354 	}
1355 
1356 	switch (ace->type) {
1357 	case ACCESS_ALLOWED_ACE_TYPE:
1358 		access_bits = le32_to_cpu(ace->access_req);
1359 		break;
1360 	case ACCESS_DENIED_ACE_TYPE:
1361 	case ACCESS_DENIED_CALLBACK_ACE_TYPE:
1362 		access_bits = le32_to_cpu(~ace->access_req);
1363 		break;
1364 	}
1365 
1366 check_access_bits:
1367 	if (granted &
1368 	    ~(access_bits | FILE_READ_ATTRIBUTES | READ_CONTROL | WRITE_DAC | DELETE)) {
1369 		ksmbd_debug(SMB, "Access denied with winACL, granted : %x, access_req : %x\n",
1370 			    granted, le32_to_cpu(ace->access_req));
1371 		rc = -EACCES;
1372 		goto err_out;
1373 	}
1374 
1375 	*pdaccess = cpu_to_le32(granted);
1376 err_out:
1377 	kfree(pntsd);
1378 	return rc;
1379 }
1380 
1381 int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
1382 		 const struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
1383 		 bool type_check, bool get_write)
1384 {
1385 	int rc;
1386 	struct smb_fattr fattr = {{0}};
1387 	struct inode *inode = d_inode(path->dentry);
1388 	struct mnt_idmap *idmap = mnt_idmap(path->mnt);
1389 	struct iattr newattrs;
1390 
1391 	fattr.cf_uid = INVALID_UID;
1392 	fattr.cf_gid = INVALID_GID;
1393 	fattr.cf_mode = inode->i_mode;
1394 
1395 	rc = parse_sec_desc(idmap, pntsd, ntsd_len, &fattr);
1396 	if (rc)
1397 		goto out;
1398 
1399 	newattrs.ia_valid = ATTR_CTIME;
1400 	if (!uid_eq(fattr.cf_uid, INVALID_UID)) {
1401 		newattrs.ia_valid |= ATTR_UID;
1402 		newattrs.ia_uid = fattr.cf_uid;
1403 	}
1404 	if (!gid_eq(fattr.cf_gid, INVALID_GID)) {
1405 		newattrs.ia_valid |= ATTR_GID;
1406 		newattrs.ia_gid = fattr.cf_gid;
1407 	}
1408 	newattrs.ia_valid |= ATTR_MODE;
1409 	newattrs.ia_mode = (inode->i_mode & ~0777) | (fattr.cf_mode & 0777);
1410 
1411 	ksmbd_vfs_remove_acl_xattrs(idmap, path);
1412 	/* Update posix acls */
1413 	if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && fattr.cf_dacls) {
1414 		rc = set_posix_acl(idmap, path->dentry,
1415 				   ACL_TYPE_ACCESS, fattr.cf_acls);
1416 		if (rc < 0)
1417 			ksmbd_debug(SMB,
1418 				    "Set posix acl(ACL_TYPE_ACCESS) failed, rc : %d\n",
1419 				    rc);
1420 		if (S_ISDIR(inode->i_mode) && fattr.cf_dacls) {
1421 			rc = set_posix_acl(idmap, path->dentry,
1422 					   ACL_TYPE_DEFAULT, fattr.cf_dacls);
1423 			if (rc)
1424 				ksmbd_debug(SMB,
1425 					    "Set posix acl(ACL_TYPE_DEFAULT) failed, rc : %d\n",
1426 					    rc);
1427 		}
1428 	}
1429 
1430 	inode_lock(inode);
1431 	rc = notify_change(idmap, path->dentry, &newattrs, NULL);
1432 	inode_unlock(inode);
1433 	if (rc)
1434 		goto out;
1435 
1436 	/* Check it only calling from SD BUFFER context */
1437 	if (type_check && !(le16_to_cpu(pntsd->type) & DACL_PRESENT))
1438 		goto out;
1439 
1440 	if (test_share_config_flag(tcon->share_conf, KSMBD_SHARE_FLAG_ACL_XATTR)) {
1441 		/* Update WinACL in xattr */
1442 		ksmbd_vfs_remove_sd_xattrs(idmap, path);
1443 		ksmbd_vfs_set_sd_xattr(conn, idmap, path, pntsd, ntsd_len,
1444 				get_write);
1445 	}
1446 
1447 out:
1448 	posix_acl_release(fattr.cf_acls);
1449 	posix_acl_release(fattr.cf_dacls);
1450 	return rc;
1451 }
1452 
1453 void ksmbd_init_domain(u32 *sub_auth)
1454 {
1455 	int i;
1456 
1457 	memcpy(&server_conf.domain_sid, &domain, sizeof(struct smb_sid));
1458 	for (i = 0; i < 3; ++i)
1459 		server_conf.domain_sid.sub_auth[i + 1] = cpu_to_le32(sub_auth[i]);
1460 }
1461