xattr.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *
   4 * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
   5 *
   6 */
   7
   8#include <linux/fs.h>
   9#include <linux/posix_acl.h>
  10#include <linux/posix_acl_xattr.h>
  11#include <linux/xattr.h>
  12
  13#include "debug.h"
  14#include "ntfs.h"
  15#include "ntfs_fs.h"
  16
  17// clang-format off
  18#define SYSTEM_DOS_ATTRIB     "system.dos_attrib"
  19#define SYSTEM_NTFS_ATTRIB    "system.ntfs_attrib"
  20#define SYSTEM_NTFS_ATTRIB_BE "system.ntfs_attrib_be"
  21#define SYSTEM_NTFS_SECURITY  "system.ntfs_security"
  22// clang-format on
  23
  24static inline size_t unpacked_ea_size(const struct EA_FULL *ea)
  25{
  26	return ea->size ? le32_to_cpu(ea->size) :
  27			  ALIGN(struct_size(ea, name,
  28					    1 + ea->name_len +
  29						    le16_to_cpu(ea->elength)),
  30				4);
  31}
  32
  33static inline size_t packed_ea_size(const struct EA_FULL *ea)
  34{
  35	return struct_size(ea, name,
  36			   1 + ea->name_len + le16_to_cpu(ea->elength)) -
  37	       offsetof(struct EA_FULL, flags);
  38}
  39
  40/*
  41 * find_ea
  42 *
  43 * Assume there is at least one xattr in the list.
  44 */
  45static inline bool find_ea(const struct EA_FULL *ea_all, u32 bytes,
  46			   const char *name, u8 name_len, u32 *off, u32 *ea_sz)
  47{
  48	u32 ea_size;
  49
  50	*off = 0;
  51	if (!ea_all)
  52		return false;
  53
  54	for (; *off < bytes; *off += ea_size) {
  55		const struct EA_FULL *ea = Add2Ptr(ea_all, *off);
  56		ea_size = unpacked_ea_size(ea);
  57		if (ea->name_len == name_len &&
  58		    !memcmp(ea->name, name, name_len)) {
  59			if (ea_sz)
  60				*ea_sz = ea_size;
  61			return true;
  62		}
  63	}
  64
  65	return false;
  66}
  67
  68/*
  69 * ntfs_read_ea - Read all extended attributes.
  70 * @ea:		New allocated memory.
  71 * @info:	Pointer into resident data.
  72 */
  73static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea,
  74			size_t add_bytes, const struct EA_INFO **info)
  75{
  76	int err = -EINVAL;
  77	struct ntfs_sb_info *sbi = ni->mi.sbi;
  78	struct ATTR_LIST_ENTRY *le = NULL;
  79	struct ATTRIB *attr_info, *attr_ea;
  80	void *ea_p;
  81	u32 size, off, ea_size;
  82
  83	static_assert(le32_to_cpu(ATTR_EA_INFO) < le32_to_cpu(ATTR_EA));
  84
  85	*ea = NULL;
  86	*info = NULL;
  87
  88	attr_info =
  89		ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, NULL);
  90	attr_ea =
  91		ni_find_attr(ni, attr_info, &le, ATTR_EA, NULL, 0, NULL, NULL);
  92
  93	if (!attr_ea || !attr_info)
  94		return 0;
  95
  96	*info = resident_data_ex(attr_info, sizeof(struct EA_INFO));
  97	if (!*info)
  98		goto out;
  99
 100	/* Check Ea limit. */
 101	size = le32_to_cpu((*info)->size);
 102	if (size > sbi->ea_max_size) {
 103		err = -EFBIG;
 104		goto out;
 105	}
 106
 107	if (attr_size(attr_ea) > sbi->ea_max_size) {
 108		err = -EFBIG;
 109		goto out;
 110	}
 111
 112	if (!size) {
 113		/* EA info persists, but xattr is empty. Looks like EA problem. */
 114		goto out;
 115	}
 116
 117	/* Allocate memory for packed Ea. */
 118	ea_p = kmalloc(size_add(size, add_bytes), GFP_NOFS);
 119	if (!ea_p)
 120		return -ENOMEM;
 121
 122	if (attr_ea->non_res) {
 123		struct runs_tree run;
 124
 125		run_init(&run);
 126
 127		err = attr_load_runs_range(ni, ATTR_EA, NULL, 0, &run, 0, size);
 128		if (!err)
 129			err = ntfs_read_run_nb(sbi, &run, 0, ea_p, size, NULL);
 130		run_close(&run);
 131
 132		if (err)
 133			goto out1;
 134	} else {
 135		void *p = resident_data_ex(attr_ea, size);
 136
 137		if (!p)
 138			goto out1;
 139		memcpy(ea_p, p, size);
 140	}
 141
 142	memset(Add2Ptr(ea_p, size), 0, add_bytes);
 143
 144	err = -EINVAL;
 145	/* Check all attributes for consistency. */
 146	for (off = 0; off < size; off += ea_size) {
 147		const struct EA_FULL *ef = Add2Ptr(ea_p, off);
 148		u32 bytes = size - off;
 149
 150		/* Check if we can use field ea->size. */
 151		if (bytes < sizeof(ef->size))
 152			goto out1;
 153
 154		if (ef->size) {
 155			ea_size = le32_to_cpu(ef->size);
 156			if (ea_size > bytes)
 157				goto out1;
 158			continue;
 159		}
 160
 161		/* Check if we can use fields ef->name_len and ef->elength. */
 162		if (bytes < offsetof(struct EA_FULL, name))
 163			goto out1;
 164
 165		ea_size = ALIGN(struct_size(ef, name,
 166					    1 + ef->name_len +
 167						    le16_to_cpu(ef->elength)),
 168				4);
 169		if (ea_size > bytes)
 170			goto out1;
 171	}
 172
 173	*ea = ea_p;
 174	return 0;
 175
 176out1:
 177	kfree(ea_p);
 178out:
 179	ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
 180	return err;
 181}
 182
 183/*
 184 * ntfs_list_ea
 185 *
 186 * Copy a list of xattrs names into the buffer
 187 * provided, or compute the buffer size required.
 188 *
 189 * Return:
 190 * * Number of bytes used / required on
 191 * * -ERRNO - on failure
 192 */
 193static ssize_t ntfs_list_ea(struct ntfs_inode *ni, char *buffer,
 194			    size_t bytes_per_buffer)
 195{
 196	const struct EA_INFO *info;
 197	struct EA_FULL *ea_all = NULL;
 198	u32 off, size;
 199	int err;
 200	size_t ret;
 201
 202	err = ntfs_read_ea(ni, &ea_all, 0, &info);
 203	if (err)
 204		return err;
 205
 206	if (!info || !ea_all)
 207		return 0;
 208
 209	size = le32_to_cpu(info->size);
 210
 211	/* Enumerate all xattrs. */
 212	ret = 0;
 213	off = 0;
 214	while (off + sizeof(struct EA_FULL) < size) {
 215		const struct EA_FULL *ea = Add2Ptr(ea_all, off);
 216		int ea_size = unpacked_ea_size(ea);
 217		u8 name_len = ea->name_len;
 218
 219		if (!name_len)
 220			break;
 221
 222		if (name_len > ea_size) {
 223			ntfs_set_state(ni->mi.sbi, NTFS_DIRTY_ERROR);
 224			err = -EINVAL; /* corrupted fs. */
 225			break;
 226		}
 227
 228		if (buffer) {
 229			/* Check if we can use field ea->name */
 230			if (off + ea_size > size)
 231				break;
 232
 233			if (ret + name_len + 1 > bytes_per_buffer) {
 234				err = -ERANGE;
 235				goto out;
 236			}
 237
 238			memcpy(buffer + ret, ea->name, name_len);
 239			buffer[ret + name_len] = 0;
 240		}
 241
 242		ret += name_len + 1;
 243		off += ea_size;
 244	}
 245
 246out:
 247	kfree(ea_all);
 248	return err ? err : ret;
 249}
 250
 251static int ntfs_get_ea(struct inode *inode, const char *name, size_t name_len,
 252		       void *buffer, size_t size, size_t *required)
 253{
 254	struct ntfs_inode *ni = ntfs_i(inode);
 255	const struct EA_INFO *info;
 256	struct EA_FULL *ea_all = NULL;
 257	const struct EA_FULL *ea;
 258	u32 off, len;
 259	int err;
 260
 261	if (!(ni->ni_flags & NI_FLAG_EA))
 262		return -ENODATA;
 263
 264	if (!required)
 265		ni_lock(ni);
 266
 267	len = 0;
 268
 269	if (name_len > 255) {
 270		err = -ENAMETOOLONG;
 271		goto out;
 272	}
 273
 274	err = ntfs_read_ea(ni, &ea_all, 0, &info);
 275	if (err)
 276		goto out;
 277
 278	if (!info)
 279		goto out;
 280
 281	/* Enumerate all xattrs. */
 282	if (!find_ea(ea_all, le32_to_cpu(info->size), name, name_len, &off,
 283		     NULL)) {
 284		err = -ENODATA;
 285		goto out;
 286	}
 287	ea = Add2Ptr(ea_all, off);
 288
 289	len = le16_to_cpu(ea->elength);
 290	if (!buffer) {
 291		err = 0;
 292		goto out;
 293	}
 294
 295	if (len > size) {
 296		err = -ERANGE;
 297		if (required)
 298			*required = len;
 299		goto out;
 300	}
 301
 302	memcpy(buffer, ea->name + ea->name_len + 1, len);
 303	err = 0;
 304
 305out:
 306	kfree(ea_all);
 307	if (!required)
 308		ni_unlock(ni);
 309
 310	return err ? err : len;
 311}
 312
 313static noinline int ntfs_set_ea(struct inode *inode, const char *name,
 314				size_t name_len, const void *value,
 315				size_t val_size, int flags, bool locked,
 316				__le32 *ea_size)
 317{
 318	struct ntfs_inode *ni = ntfs_i(inode);
 319	struct ntfs_sb_info *sbi = ni->mi.sbi;
 320	int err;
 321	struct EA_INFO ea_info;
 322	const struct EA_INFO *info;
 323	struct EA_FULL *new_ea;
 324	struct EA_FULL *ea_all = NULL;
 325	size_t add, new_pack;
 326	u32 off, size, ea_sz;
 327	__le16 size_pack;
 328	struct ATTRIB *attr;
 329	struct ATTR_LIST_ENTRY *le;
 330	struct mft_inode *mi;
 331	struct runs_tree ea_run;
 332	u64 new_sz;
 333	void *p;
 334
 335	if (!locked)
 336		ni_lock(ni);
 337
 338	run_init(&ea_run);
 339
 340	if (name_len > 255) {
 341		err = -ENAMETOOLONG;
 342		goto out;
 343	}
 344
 345	add = ALIGN(struct_size(ea_all, name, 1 + name_len + val_size), 4);
 346
 347	err = ntfs_read_ea(ni, &ea_all, add, &info);
 348	if (err)
 349		goto out;
 350
 351	if (!info) {
 352		memset(&ea_info, 0, sizeof(ea_info));
 353		size = 0;
 354		size_pack = 0;
 355	} else {
 356		memcpy(&ea_info, info, sizeof(ea_info));
 357		size = le32_to_cpu(ea_info.size);
 358		size_pack = ea_info.size_pack;
 359	}
 360
 361	if (info && find_ea(ea_all, size, name, name_len, &off, &ea_sz)) {
 362		struct EA_FULL *ea;
 363
 364		if (flags & XATTR_CREATE) {
 365			err = -EEXIST;
 366			goto out;
 367		}
 368
 369		ea = Add2Ptr(ea_all, off);
 370
 371		/*
 372		 * Check simple case when we try to insert xattr with the same value
 373		 * e.g. ntfs_save_wsl_perm
 374		 */
 375		if (val_size && le16_to_cpu(ea->elength) == val_size &&
 376		    !memcmp(ea->name + ea->name_len + 1, value, val_size)) {
 377			/* xattr already contains the required value. */
 378			goto out;
 379		}
 380
 381		/* Remove current xattr. */
 382		if (ea->flags & FILE_NEED_EA)
 383			le16_add_cpu(&ea_info.count, -1);
 384
 385		le16_add_cpu(&ea_info.size_pack, 0 - packed_ea_size(ea));
 386
 387		memmove(ea, Add2Ptr(ea, ea_sz), size - off - ea_sz);
 388
 389		size -= ea_sz;
 390		memset(Add2Ptr(ea_all, size), 0, ea_sz);
 391
 392		ea_info.size = cpu_to_le32(size);
 393
 394		if ((flags & XATTR_REPLACE) && !val_size) {
 395			/* Remove xattr. */
 396			goto update_ea;
 397		}
 398	} else {
 399		if (flags & XATTR_REPLACE) {
 400			err = -ENODATA;
 401			goto out;
 402		}
 403
 404		if (!ea_all) {
 405			ea_all = kzalloc(add, GFP_NOFS);
 406			if (!ea_all) {
 407				err = -ENOMEM;
 408				goto out;
 409			}
 410		}
 411	}
 412
 413	/* Append new xattr. */
 414	new_ea = Add2Ptr(ea_all, size);
 415	new_ea->size = cpu_to_le32(add);
 416	new_ea->flags = 0;
 417	new_ea->name_len = name_len;
 418	new_ea->elength = cpu_to_le16(val_size);
 419	memcpy(new_ea->name, name, name_len);
 420	new_ea->name[name_len] = 0;
 421	memcpy(new_ea->name + name_len + 1, value, val_size);
 422	new_pack = le16_to_cpu(ea_info.size_pack) + packed_ea_size(new_ea);
 423	ea_info.size_pack = cpu_to_le16(new_pack);
 424	/* New size of ATTR_EA. */
 425	size += add;
 426	ea_info.size = cpu_to_le32(size);
 427
 428	/*
 429	 * 1. Check ea_info.size_pack for overflow.
 430	 * 2. New attribute size must fit value from $AttrDef
 431	 */
 432	if (new_pack > 0xffff || size > sbi->ea_max_size) {
 433		ntfs_inode_warn(
 434			inode,
 435			"The size of extended attributes must not exceed 64KiB");
 436		err = -EFBIG; // -EINVAL?
 437		goto out;
 438	}
 439
 440update_ea:
 441
 442	if (!info) {
 443		/* Create xattr. */
 444		if (!size) {
 445			err = 0;
 446			goto out;
 447		}
 448
 449		err = ni_insert_resident(ni, sizeof(struct EA_INFO),
 450					 ATTR_EA_INFO, NULL, 0, NULL, NULL,
 451					 NULL);
 452		if (err)
 453			goto out;
 454
 455		err = ni_insert_resident(ni, 0, ATTR_EA, NULL, 0, NULL, NULL,
 456					 NULL);
 457		if (err)
 458			goto out;
 459	}
 460
 461	new_sz = size;
 462	err = attr_set_size(ni, ATTR_EA, NULL, 0, &ea_run, new_sz, &new_sz,
 463			    false, NULL);
 464	if (err)
 465		goto out;
 466
 467	le = NULL;
 468	attr = ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, &mi);
 469	if (!attr) {
 470		err = -EINVAL;
 471		goto out;
 472	}
 473
 474	if (!size) {
 475		/* Delete xattr, ATTR_EA_INFO */
 476		ni_remove_attr_le(ni, attr, mi, le);
 477	} else {
 478		p = resident_data_ex(attr, sizeof(struct EA_INFO));
 479		if (!p) {
 480			err = -EINVAL;
 481			goto out;
 482		}
 483		memcpy(p, &ea_info, sizeof(struct EA_INFO));
 484		mi->dirty = true;
 485	}
 486
 487	le = NULL;
 488	attr = ni_find_attr(ni, NULL, &le, ATTR_EA, NULL, 0, NULL, &mi);
 489	if (!attr) {
 490		err = -EINVAL;
 491		goto out;
 492	}
 493
 494	if (!size) {
 495		/* Delete xattr, ATTR_EA */
 496		ni_remove_attr_le(ni, attr, mi, le);
 497	} else if (attr->non_res) {
 498		err = attr_load_runs_range(ni, ATTR_EA, NULL, 0, &ea_run, 0,
 499					   size);
 500		if (err)
 501			goto out;
 502
 503		err = ntfs_sb_write_run(sbi, &ea_run, 0, ea_all, size, 0);
 504		if (err)
 505			goto out;
 506	} else {
 507		p = resident_data_ex(attr, size);
 508		if (!p) {
 509			err = -EINVAL;
 510			goto out;
 511		}
 512		memcpy(p, ea_all, size);
 513		mi->dirty = true;
 514	}
 515
 516	/* Check if we delete the last xattr. */
 517	if (size)
 518		ni->ni_flags |= NI_FLAG_EA;
 519	else
 520		ni->ni_flags &= ~NI_FLAG_EA;
 521
 522	if (ea_info.size_pack != size_pack)
 523		ni->ni_flags |= NI_FLAG_UPDATE_PARENT;
 524	if (ea_size)
 525		*ea_size = ea_info.size;
 526	mark_inode_dirty(&ni->vfs_inode);
 527
 528out:
 529	if (!locked)
 530		ni_unlock(ni);
 531
 532	run_close(&ea_run);
 533	kfree(ea_all);
 534
 535	return err;
 536}
 537
 538#ifdef CONFIG_NTFS3_FS_POSIX_ACL
 539
 540/*
 541 * ntfs_get_acl - inode_operations::get_acl
 542 */
 543struct posix_acl *ntfs_get_acl(struct mnt_idmap *idmap, struct dentry *dentry,
 544			       int type)
 545{
 546	struct inode *inode = d_inode(dentry);
 547	struct ntfs_inode *ni = ntfs_i(inode);
 548	const char *name;
 549	size_t name_len;
 550	struct posix_acl *acl;
 551	size_t req;
 552	int err;
 553	void *buf;
 554
 555	/* Avoid any operation if inode is bad. */
 556	if (unlikely(is_bad_ni(ni)))
 557		return ERR_PTR(-EINVAL);
 558
 559	buf = kmalloc(PATH_MAX, GFP_KERNEL);
 560	if (!buf)
 561		return ERR_PTR(-ENOMEM);
 562
 563	/* Possible values of 'type' was already checked above. */
 564	if (type == ACL_TYPE_ACCESS) {
 565		name = XATTR_NAME_POSIX_ACL_ACCESS;
 566		name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
 567	} else {
 568		name = XATTR_NAME_POSIX_ACL_DEFAULT;
 569		name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
 570	}
 571
 572	ni_lock(ni);
 573
 574	err = ntfs_get_ea(inode, name, name_len, buf, PATH_MAX, &req);
 575
 576	ni_unlock(ni);
 577
 578	/* Translate extended attribute to acl. */
 579	if (err >= 0) {
 580		acl = posix_acl_from_xattr(&init_user_ns, buf, err);
 581	} else if (err == -ENODATA) {
 582		acl = NULL;
 583	} else {
 584		acl = ERR_PTR(err);
 585	}
 586
 587	if (!IS_ERR(acl))
 588		set_cached_acl(inode, type, acl);
 589
 590	kfree(buf);
 591
 592	return acl;
 593}
 594
 595static noinline int ntfs_set_acl_ex(struct mnt_idmap *idmap,
 596				    struct inode *inode, struct posix_acl *acl,
 597				    int type, bool init_acl)
 598{
 599	const char *name;
 600	size_t size, name_len;
 601	void *value;
 602	int err;
 603	int flags;
 604	umode_t mode;
 605
 606	/* Avoid any operation if inode is bad. */
 607	if (unlikely(is_bad_ni(ntfs_i(inode))))
 608		return -EINVAL;
 609
 610	if (S_ISLNK(inode->i_mode))
 611		return -EOPNOTSUPP;
 612
 613	mode = inode->i_mode;
 614	switch (type) {
 615	case ACL_TYPE_ACCESS:
 616		/* Do not change i_mode if we are in init_acl */
 617		if (acl && !init_acl) {
 618			err = posix_acl_update_mode(idmap, inode, &mode, &acl);
 619			if (err)
 620				return err;
 621		}
 622		name = XATTR_NAME_POSIX_ACL_ACCESS;
 623		name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
 624		break;
 625
 626	case ACL_TYPE_DEFAULT:
 627		if (!S_ISDIR(inode->i_mode))
 628			return acl ? -EACCES : 0;
 629		name = XATTR_NAME_POSIX_ACL_DEFAULT;
 630		name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
 631		break;
 632
 633	default:
 634		return -EINVAL;
 635	}
 636
 637	if (!acl) {
 638		/* Remove xattr if it can be presented via mode. */
 639		size = 0;
 640		value = NULL;
 641		flags = XATTR_REPLACE;
 642	} else {
 643		size = posix_acl_xattr_size(acl->a_count);
 644		value = kmalloc(size, GFP_NOFS);
 645		if (!value)
 646			return -ENOMEM;
 647		err = posix_acl_to_xattr(&init_user_ns, acl, value, size);
 648		if (err < 0)
 649			goto out;
 650		flags = 0;
 651	}
 652
 653	err = ntfs_set_ea(inode, name, name_len, value, size, flags, 0, NULL);
 654	if (err == -ENODATA && !size)
 655		err = 0; /* Removing non existed xattr. */
 656	if (err)
 657		goto out;
 658
 659	if (inode->i_mode != mode) {
 660		umode_t old_mode = inode->i_mode;
 661		inode->i_mode = mode;
 662		err = ntfs_save_wsl_perm(inode, NULL);
 663		if (err) {
 664			inode->i_mode = old_mode;
 665			goto out;
 666		}
 667		inode->i_mode = mode;
 668	}
 669	set_cached_acl(inode, type, acl);
 670	inode_set_ctime_current(inode);
 671	mark_inode_dirty(inode);
 672
 673out:
 674	kfree(value);
 675
 676	return err;
 677}
 678
 679/*
 680 * ntfs_set_acl - inode_operations::set_acl
 681 */
 682int ntfs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
 683		 struct posix_acl *acl, int type)
 684{
 685	return ntfs_set_acl_ex(idmap, d_inode(dentry), acl, type, false);
 686}
 687
 688/*
 689 * ntfs_init_acl - Initialize the ACLs of a new inode.
 690 *
 691 * Called from ntfs_create_inode().
 692 */
 693int ntfs_init_acl(struct mnt_idmap *idmap, struct inode *inode,
 694		  struct inode *dir)
 695{
 696	struct posix_acl *default_acl, *acl;
 697	int err;
 698
 699	err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
 700	if (err)
 701		return err;
 702
 703	if (default_acl) {
 704		err = ntfs_set_acl_ex(idmap, inode, default_acl,
 705				      ACL_TYPE_DEFAULT, true);
 706		posix_acl_release(default_acl);
 707	} else {
 708		inode->i_default_acl = NULL;
 709	}
 710
 711	if (acl) {
 712		if (!err)
 713			err = ntfs_set_acl_ex(idmap, inode, acl,
 714					      ACL_TYPE_ACCESS, true);
 715		posix_acl_release(acl);
 716	} else {
 717		inode->i_acl = NULL;
 718	}
 719
 720	return err;
 721}
 722#endif
 723
 724/*
 725 * ntfs_acl_chmod - Helper for ntfs_setattr().
 726 */
 727int ntfs_acl_chmod(struct mnt_idmap *idmap, struct dentry *dentry)
 728{
 729	struct inode *inode = d_inode(dentry);
 730	struct super_block *sb = inode->i_sb;
 731
 732	if (!(sb->s_flags & SB_POSIXACL))
 733		return 0;
 734
 735	if (S_ISLNK(inode->i_mode))
 736		return -EOPNOTSUPP;
 737
 738	return posix_acl_chmod(idmap, dentry, inode->i_mode);
 739}
 740
 741/*
 742 * ntfs_listxattr - inode_operations::listxattr
 743 */
 744ssize_t ntfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
 745{
 746	struct inode *inode = d_inode(dentry);
 747	struct ntfs_inode *ni = ntfs_i(inode);
 748	ssize_t ret;
 749
 750	/* Avoid any operation if inode is bad. */
 751	if (unlikely(is_bad_ni(ni)))
 752		return -EINVAL;
 753
 754	if (!(ni->ni_flags & NI_FLAG_EA)) {
 755		/* no xattr in file */
 756		return 0;
 757	}
 758
 759	ni_lock(ni);
 760
 761	ret = ntfs_list_ea(ni, buffer, size);
 762
 763	ni_unlock(ni);
 764
 765	return ret;
 766}
 767
 768static int ntfs_getxattr(const struct xattr_handler *handler, struct dentry *de,
 769			 struct inode *inode, const char *name, void *buffer,
 770			 size_t size)
 771{
 772	int err;
 773	struct ntfs_inode *ni = ntfs_i(inode);
 774
 775	/* Avoid any operation if inode is bad. */
 776	if (unlikely(is_bad_ni(ni)))
 777		return -EINVAL;
 778
 779	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
 780		return -EIO;
 781
 782	/* Dispatch request. */
 783	if (!strcmp(name, SYSTEM_DOS_ATTRIB)) {
 784		/* system.dos_attrib */
 785		if (!buffer) {
 786			err = sizeof(u8);
 787		} else if (size < sizeof(u8)) {
 788			err = -ENODATA;
 789		} else {
 790			err = sizeof(u8);
 791			*(u8 *)buffer = le32_to_cpu(ni->std_fa);
 792		}
 793		goto out;
 794	}
 795
 796	if (!strcmp(name, SYSTEM_NTFS_ATTRIB) ||
 797	    !strcmp(name, SYSTEM_NTFS_ATTRIB_BE)) {
 798		/* system.ntfs_attrib */
 799		if (!buffer) {
 800			err = sizeof(u32);
 801		} else if (size < sizeof(u32)) {
 802			err = -ENODATA;
 803		} else {
 804			err = sizeof(u32);
 805			*(u32 *)buffer = le32_to_cpu(ni->std_fa);
 806			if (!strcmp(name, SYSTEM_NTFS_ATTRIB_BE))
 807				*(__be32 *)buffer = cpu_to_be32(*(u32 *)buffer);
 808		}
 809		goto out;
 810	}
 811
 812	if (!strcmp(name, SYSTEM_NTFS_SECURITY)) {
 813		/* system.ntfs_security*/
 814		struct SECURITY_DESCRIPTOR_RELATIVE *sd = NULL;
 815		size_t sd_size = 0;
 816
 817		if (!is_ntfs3(ni->mi.sbi)) {
 818			/* We should get nt4 security. */
 819			err = -EINVAL;
 820			goto out;
 821		} else if (le32_to_cpu(ni->std_security_id) <
 822			   SECURITY_ID_FIRST) {
 823			err = -ENOENT;
 824			goto out;
 825		}
 826
 827		err = ntfs_get_security_by_id(ni->mi.sbi, ni->std_security_id,
 828					      &sd, &sd_size);
 829		if (err)
 830			goto out;
 831
 832		if (!is_sd_valid(sd, sd_size)) {
 833			ntfs_inode_warn(
 834				inode,
 835				"looks like you get incorrect security descriptor id=%u",
 836				ni->std_security_id);
 837		}
 838
 839		if (!buffer) {
 840			err = sd_size;
 841		} else if (size < sd_size) {
 842			err = -ENODATA;
 843		} else {
 844			err = sd_size;
 845			memcpy(buffer, sd, sd_size);
 846		}
 847		kfree(sd);
 848		goto out;
 849	}
 850
 851	/* Deal with NTFS extended attribute. */
 852	err = ntfs_get_ea(inode, name, strlen(name), buffer, size, NULL);
 853
 854out:
 855	return err;
 856}
 857
 858/*
 859 * ntfs_setxattr - inode_operations::setxattr
 860 */
 861static noinline int ntfs_setxattr(const struct xattr_handler *handler,
 862				  struct mnt_idmap *idmap, struct dentry *de,
 863				  struct inode *inode, const char *name,
 864				  const void *value, size_t size, int flags)
 865{
 866	int err = -EINVAL;
 867	struct ntfs_inode *ni = ntfs_i(inode);
 868	enum FILE_ATTRIBUTE new_fa;
 869
 870	/* Dispatch request. */
 871	if (!strcmp(name, SYSTEM_DOS_ATTRIB)) {
 872		if (sizeof(u8) != size)
 873			goto out;
 874		new_fa = cpu_to_le32(*(u8 *)value);
 875		goto set_new_fa;
 876	}
 877
 878	if (!strcmp(name, SYSTEM_NTFS_ATTRIB) ||
 879	    !strcmp(name, SYSTEM_NTFS_ATTRIB_BE)) {
 880		if (size != sizeof(u32))
 881			goto out;
 882		if (!strcmp(name, SYSTEM_NTFS_ATTRIB_BE))
 883			new_fa = cpu_to_le32(be32_to_cpu(*(__be32 *)value));
 884		else
 885			new_fa = cpu_to_le32(*(u32 *)value);
 886
 887		if (S_ISREG(inode->i_mode)) {
 888			/* Process compressed/sparsed in special way. */
 889			ni_lock(ni);
 890			err = ni_new_attr_flags(ni, new_fa);
 891			ni_unlock(ni);
 892			if (err)
 893				goto out;
 894		}
 895set_new_fa:
 896		/*
 897		 * Thanks Mark Harmstone:
 898		 * Keep directory bit consistency.
 899		 */
 900		if (S_ISDIR(inode->i_mode))
 901			new_fa |= FILE_ATTRIBUTE_DIRECTORY;
 902		else
 903			new_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
 904
 905		if (ni->std_fa != new_fa) {
 906			ni->std_fa = new_fa;
 907			if (new_fa & FILE_ATTRIBUTE_READONLY)
 908				inode->i_mode &= ~0222;
 909			else
 910				inode->i_mode |= 0222;
 911			/* Std attribute always in primary record. */
 912			ni->mi.dirty = true;
 913			mark_inode_dirty(inode);
 914		}
 915		err = 0;
 916
 917		goto out;
 918	}
 919
 920	if (!strcmp(name, SYSTEM_NTFS_SECURITY)) {
 921		/* system.ntfs_security*/
 922		__le32 security_id;
 923		bool inserted;
 924		struct ATTR_STD_INFO5 *std;
 925
 926		if (!is_ntfs3(ni->mi.sbi)) {
 927			/*
 928			 * We should replace ATTR_SECURE.
 929			 * Skip this way cause it is nt4 feature.
 930			 */
 931			err = -EINVAL;
 932			goto out;
 933		}
 934
 935		if (!is_sd_valid(value, size)) {
 936			err = -EINVAL;
 937			ntfs_inode_warn(
 938				inode,
 939				"you try to set invalid security descriptor");
 940			goto out;
 941		}
 942
 943		err = ntfs_insert_security(ni->mi.sbi, value, size,
 944					   &security_id, &inserted);
 945		if (err)
 946			goto out;
 947
 948		ni_lock(ni);
 949		std = ni_std5(ni);
 950		if (!std) {
 951			err = -EINVAL;
 952		} else if (std->security_id != security_id) {
 953			std->security_id = ni->std_security_id = security_id;
 954			/* Std attribute always in primary record. */
 955			ni->mi.dirty = true;
 956			mark_inode_dirty(&ni->vfs_inode);
 957		}
 958		ni_unlock(ni);
 959		goto out;
 960	}
 961
 962	/* Deal with NTFS extended attribute. */
 963	err = ntfs_set_ea(inode, name, strlen(name), value, size, flags, 0,
 964			  NULL);
 965
 966out:
 967	inode_set_ctime_current(inode);
 968	mark_inode_dirty(inode);
 969
 970	return err;
 971}
 972
 973/*
 974 * ntfs_save_wsl_perm
 975 *
 976 * save uid/gid/mode in xattr
 977 */
 978int ntfs_save_wsl_perm(struct inode *inode, __le32 *ea_size)
 979{
 980	int err;
 981	__le32 value;
 982	struct ntfs_inode *ni = ntfs_i(inode);
 983
 984	ni_lock(ni);
 985	value = cpu_to_le32(i_uid_read(inode));
 986	err = ntfs_set_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value,
 987			  sizeof(value), 0, true, ea_size);
 988	if (err)
 989		goto out;
 990
 991	value = cpu_to_le32(i_gid_read(inode));
 992	err = ntfs_set_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value,
 993			  sizeof(value), 0, true, ea_size);
 994	if (err)
 995		goto out;
 996
 997	value = cpu_to_le32(inode->i_mode);
 998	err = ntfs_set_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value,
 999			  sizeof(value), 0, true, ea_size);
1000	if (err)
1001		goto out;
1002
1003	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1004		value = cpu_to_le32(inode->i_rdev);
1005		err = ntfs_set_ea(inode, "$LXDEV", sizeof("$LXDEV") - 1, &value,
1006				  sizeof(value), 0, true, ea_size);
1007		if (err)
1008			goto out;
1009	}
1010
1011out:
1012	ni_unlock(ni);
1013	/* In case of error should we delete all WSL xattr? */
1014	return err;
1015}
1016
1017/*
1018 * ntfs_get_wsl_perm
1019 *
1020 * get uid/gid/mode from xattr
1021 * it is called from ntfs_iget5->ntfs_read_mft
1022 */
1023void ntfs_get_wsl_perm(struct inode *inode)
1024{
1025	size_t sz;
1026	__le32 value[3];
1027
1028	if (ntfs_get_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value[0],
1029			sizeof(value[0]), &sz) == sizeof(value[0]) &&
1030	    ntfs_get_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value[1],
1031			sizeof(value[1]), &sz) == sizeof(value[1]) &&
1032	    ntfs_get_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value[2],
1033			sizeof(value[2]), &sz) == sizeof(value[2])) {
1034		i_uid_write(inode, (uid_t)le32_to_cpu(value[0]));
1035		i_gid_write(inode, (gid_t)le32_to_cpu(value[1]));
1036		inode->i_mode = le32_to_cpu(value[2]);
1037
1038		if (ntfs_get_ea(inode, "$LXDEV", sizeof("$$LXDEV") - 1,
1039				&value[0], sizeof(value),
1040				&sz) == sizeof(value[0])) {
1041			inode->i_rdev = le32_to_cpu(value[0]);
1042		}
1043	}
1044}
1045
1046static bool ntfs_xattr_user_list(struct dentry *dentry)
1047{
1048	return true;
1049}
1050
1051// clang-format off
1052static const struct xattr_handler ntfs_other_xattr_handler = {
1053	.prefix	= "",
1054	.get	= ntfs_getxattr,
1055	.set	= ntfs_setxattr,
1056	.list	= ntfs_xattr_user_list,
1057};
1058
1059const struct xattr_handler * const ntfs_xattr_handlers[] = {
1060	&ntfs_other_xattr_handler,
1061	NULL,
1062};
1063// clang-format on