451 lines · c
1// SPDX-License-Identifier: GPL-2.02 3#include "bcachefs.h"4 5#include "acl.h"6#include "xattr.h"7 8#include <linux/posix_acl.h>9 10static const char * const acl_types[] = {11 [ACL_USER_OBJ] = "user_obj",12 [ACL_USER] = "user",13 [ACL_GROUP_OBJ] = "group_obj",14 [ACL_GROUP] = "group",15 [ACL_MASK] = "mask",16 [ACL_OTHER] = "other",17 NULL,18};19 20void bch2_acl_to_text(struct printbuf *out, const void *value, size_t size)21{22 const void *p, *end = value + size;23 24 if (!value ||25 size < sizeof(bch_acl_header) ||26 ((bch_acl_header *)value)->a_version != cpu_to_le32(BCH_ACL_VERSION))27 return;28 29 p = value + sizeof(bch_acl_header);30 while (p < end) {31 const bch_acl_entry *in = p;32 unsigned tag = le16_to_cpu(in->e_tag);33 34 prt_str(out, acl_types[tag]);35 36 switch (tag) {37 case ACL_USER_OBJ:38 case ACL_GROUP_OBJ:39 case ACL_MASK:40 case ACL_OTHER:41 p += sizeof(bch_acl_entry_short);42 break;43 case ACL_USER:44 prt_printf(out, " uid %u", le32_to_cpu(in->e_id));45 p += sizeof(bch_acl_entry);46 break;47 case ACL_GROUP:48 prt_printf(out, " gid %u", le32_to_cpu(in->e_id));49 p += sizeof(bch_acl_entry);50 break;51 }52 53 prt_printf(out, " %o", le16_to_cpu(in->e_perm));54 55 if (p != end)56 prt_char(out, ' ');57 }58}59 60#ifdef CONFIG_BCACHEFS_POSIX_ACL61 62#include "fs.h"63 64#include <linux/fs.h>65#include <linux/posix_acl_xattr.h>66#include <linux/sched.h>67#include <linux/slab.h>68 69static inline size_t bch2_acl_size(unsigned nr_short, unsigned nr_long)70{71 return sizeof(bch_acl_header) +72 sizeof(bch_acl_entry_short) * nr_short +73 sizeof(bch_acl_entry) * nr_long;74}75 76static inline int acl_to_xattr_type(int type)77{78 switch (type) {79 case ACL_TYPE_ACCESS:80 return KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS;81 case ACL_TYPE_DEFAULT:82 return KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT;83 default:84 BUG();85 }86}87 88/*89 * Convert from filesystem to in-memory representation.90 */91static struct posix_acl *bch2_acl_from_disk(struct btree_trans *trans,92 const void *value, size_t size)93{94 const void *p, *end = value + size;95 struct posix_acl *acl;96 struct posix_acl_entry *out;97 unsigned count = 0;98 int ret;99 100 if (!value)101 return NULL;102 if (size < sizeof(bch_acl_header))103 goto invalid;104 if (((bch_acl_header *)value)->a_version !=105 cpu_to_le32(BCH_ACL_VERSION))106 goto invalid;107 108 p = value + sizeof(bch_acl_header);109 while (p < end) {110 const bch_acl_entry *entry = p;111 112 if (p + sizeof(bch_acl_entry_short) > end)113 goto invalid;114 115 switch (le16_to_cpu(entry->e_tag)) {116 case ACL_USER_OBJ:117 case ACL_GROUP_OBJ:118 case ACL_MASK:119 case ACL_OTHER:120 p += sizeof(bch_acl_entry_short);121 break;122 case ACL_USER:123 case ACL_GROUP:124 p += sizeof(bch_acl_entry);125 break;126 default:127 goto invalid;128 }129 130 count++;131 }132 133 if (p > end)134 goto invalid;135 136 if (!count)137 return NULL;138 139 acl = allocate_dropping_locks(trans, ret,140 posix_acl_alloc(count, _gfp));141 if (!acl)142 return ERR_PTR(-ENOMEM);143 if (ret) {144 kfree(acl);145 return ERR_PTR(ret);146 }147 148 out = acl->a_entries;149 150 p = value + sizeof(bch_acl_header);151 while (p < end) {152 const bch_acl_entry *in = p;153 154 out->e_tag = le16_to_cpu(in->e_tag);155 out->e_perm = le16_to_cpu(in->e_perm);156 157 switch (out->e_tag) {158 case ACL_USER_OBJ:159 case ACL_GROUP_OBJ:160 case ACL_MASK:161 case ACL_OTHER:162 p += sizeof(bch_acl_entry_short);163 break;164 case ACL_USER:165 out->e_uid = make_kuid(&init_user_ns,166 le32_to_cpu(in->e_id));167 p += sizeof(bch_acl_entry);168 break;169 case ACL_GROUP:170 out->e_gid = make_kgid(&init_user_ns,171 le32_to_cpu(in->e_id));172 p += sizeof(bch_acl_entry);173 break;174 }175 176 out++;177 }178 179 BUG_ON(out != acl->a_entries + acl->a_count);180 181 return acl;182invalid:183 pr_err("invalid acl entry");184 return ERR_PTR(-EINVAL);185}186 187#define acl_for_each_entry(acl, acl_e) \188 for (acl_e = acl->a_entries; \189 acl_e < acl->a_entries + acl->a_count; \190 acl_e++)191 192/*193 * Convert from in-memory to filesystem representation.194 */195static struct bkey_i_xattr *196bch2_acl_to_xattr(struct btree_trans *trans,197 const struct posix_acl *acl,198 int type)199{200 struct bkey_i_xattr *xattr;201 bch_acl_header *acl_header;202 const struct posix_acl_entry *acl_e;203 void *outptr;204 unsigned nr_short = 0, nr_long = 0, acl_len, u64s;205 206 acl_for_each_entry(acl, acl_e) {207 switch (acl_e->e_tag) {208 case ACL_USER:209 case ACL_GROUP:210 nr_long++;211 break;212 case ACL_USER_OBJ:213 case ACL_GROUP_OBJ:214 case ACL_MASK:215 case ACL_OTHER:216 nr_short++;217 break;218 default:219 return ERR_PTR(-EINVAL);220 }221 }222 223 acl_len = bch2_acl_size(nr_short, nr_long);224 u64s = BKEY_U64s + xattr_val_u64s(0, acl_len);225 226 if (u64s > U8_MAX)227 return ERR_PTR(-E2BIG);228 229 xattr = bch2_trans_kmalloc(trans, u64s * sizeof(u64));230 if (IS_ERR(xattr))231 return xattr;232 233 bkey_xattr_init(&xattr->k_i);234 xattr->k.u64s = u64s;235 xattr->v.x_type = acl_to_xattr_type(type);236 xattr->v.x_name_len = 0;237 xattr->v.x_val_len = cpu_to_le16(acl_len);238 239 acl_header = xattr_val(&xattr->v);240 acl_header->a_version = cpu_to_le32(BCH_ACL_VERSION);241 242 outptr = (void *) acl_header + sizeof(*acl_header);243 244 acl_for_each_entry(acl, acl_e) {245 bch_acl_entry *entry = outptr;246 247 entry->e_tag = cpu_to_le16(acl_e->e_tag);248 entry->e_perm = cpu_to_le16(acl_e->e_perm);249 switch (acl_e->e_tag) {250 case ACL_USER:251 entry->e_id = cpu_to_le32(252 from_kuid(&init_user_ns, acl_e->e_uid));253 outptr += sizeof(bch_acl_entry);254 break;255 case ACL_GROUP:256 entry->e_id = cpu_to_le32(257 from_kgid(&init_user_ns, acl_e->e_gid));258 outptr += sizeof(bch_acl_entry);259 break;260 261 case ACL_USER_OBJ:262 case ACL_GROUP_OBJ:263 case ACL_MASK:264 case ACL_OTHER:265 outptr += sizeof(bch_acl_entry_short);266 break;267 }268 }269 270 BUG_ON(outptr != xattr_val(&xattr->v) + acl_len);271 272 return xattr;273}274 275struct posix_acl *bch2_get_acl(struct inode *vinode, int type, bool rcu)276{277 struct bch_inode_info *inode = to_bch_ei(vinode);278 struct bch_fs *c = inode->v.i_sb->s_fs_info;279 struct bch_hash_info hash = bch2_hash_info_init(c, &inode->ei_inode);280 struct xattr_search_key search = X_SEARCH(acl_to_xattr_type(type), "", 0);281 struct btree_iter iter = { NULL };282 struct posix_acl *acl = NULL;283 284 if (rcu)285 return ERR_PTR(-ECHILD);286 287 struct btree_trans *trans = bch2_trans_get(c);288retry:289 bch2_trans_begin(trans);290 291 struct bkey_s_c k = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc,292 &hash, inode_inum(inode), &search, 0);293 int ret = bkey_err(k);294 if (ret)295 goto err;296 297 struct bkey_s_c_xattr xattr = bkey_s_c_to_xattr(k);298 acl = bch2_acl_from_disk(trans, xattr_val(xattr.v),299 le16_to_cpu(xattr.v->x_val_len));300 ret = PTR_ERR_OR_ZERO(acl);301err:302 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))303 goto retry;304 305 if (ret)306 acl = !bch2_err_matches(ret, ENOENT) ? ERR_PTR(ret) : NULL;307 308 if (!IS_ERR_OR_NULL(acl))309 set_cached_acl(&inode->v, type, acl);310 311 bch2_trans_iter_exit(trans, &iter);312 bch2_trans_put(trans);313 return acl;314}315 316int bch2_set_acl_trans(struct btree_trans *trans, subvol_inum inum,317 struct bch_inode_unpacked *inode_u,318 struct posix_acl *acl, int type)319{320 struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode_u);321 int ret;322 323 if (type == ACL_TYPE_DEFAULT &&324 !S_ISDIR(inode_u->bi_mode))325 return acl ? -EACCES : 0;326 327 if (acl) {328 struct bkey_i_xattr *xattr =329 bch2_acl_to_xattr(trans, acl, type);330 if (IS_ERR(xattr))331 return PTR_ERR(xattr);332 333 ret = bch2_hash_set(trans, bch2_xattr_hash_desc, &hash_info,334 inum, &xattr->k_i, 0);335 } else {336 struct xattr_search_key search =337 X_SEARCH(acl_to_xattr_type(type), "", 0);338 339 ret = bch2_hash_delete(trans, bch2_xattr_hash_desc, &hash_info,340 inum, &search);341 }342 343 return bch2_err_matches(ret, ENOENT) ? 0 : ret;344}345 346int bch2_set_acl(struct mnt_idmap *idmap,347 struct dentry *dentry,348 struct posix_acl *_acl, int type)349{350 struct bch_inode_info *inode = to_bch_ei(dentry->d_inode);351 struct bch_fs *c = inode->v.i_sb->s_fs_info;352 struct btree_iter inode_iter = { NULL };353 struct bch_inode_unpacked inode_u;354 struct posix_acl *acl;355 umode_t mode;356 int ret;357 358 mutex_lock(&inode->ei_update_lock);359 struct btree_trans *trans = bch2_trans_get(c);360retry:361 bch2_trans_begin(trans);362 acl = _acl;363 364 ret = bch2_subvol_is_ro_trans(trans, inode->ei_inum.subvol) ?:365 bch2_inode_peek(trans, &inode_iter, &inode_u, inode_inum(inode),366 BTREE_ITER_intent);367 if (ret)368 goto btree_err;369 370 mode = inode_u.bi_mode;371 372 if (type == ACL_TYPE_ACCESS) {373 ret = posix_acl_update_mode(idmap, &inode->v, &mode, &acl);374 if (ret)375 goto btree_err;376 }377 378 ret = bch2_set_acl_trans(trans, inode_inum(inode), &inode_u, acl, type);379 if (ret)380 goto btree_err;381 382 inode_u.bi_ctime = bch2_current_time(c);383 inode_u.bi_mode = mode;384 385 ret = bch2_inode_write(trans, &inode_iter, &inode_u) ?:386 bch2_trans_commit(trans, NULL, NULL, 0);387btree_err:388 bch2_trans_iter_exit(trans, &inode_iter);389 390 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))391 goto retry;392 if (unlikely(ret))393 goto err;394 395 bch2_inode_update_after_write(trans, inode, &inode_u,396 ATTR_CTIME|ATTR_MODE);397 398 set_cached_acl(&inode->v, type, acl);399err:400 bch2_trans_put(trans);401 mutex_unlock(&inode->ei_update_lock);402 403 return ret;404}405 406int bch2_acl_chmod(struct btree_trans *trans, subvol_inum inum,407 struct bch_inode_unpacked *inode,408 umode_t mode,409 struct posix_acl **new_acl)410{411 struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode);412 struct xattr_search_key search = X_SEARCH(KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS, "", 0);413 struct btree_iter iter;414 struct posix_acl *acl = NULL;415 416 struct bkey_s_c k = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc,417 &hash_info, inum, &search, BTREE_ITER_intent);418 int ret = bkey_err(k);419 if (ret)420 return bch2_err_matches(ret, ENOENT) ? 0 : ret;421 422 struct bkey_s_c_xattr xattr = bkey_s_c_to_xattr(k);423 424 acl = bch2_acl_from_disk(trans, xattr_val(xattr.v),425 le16_to_cpu(xattr.v->x_val_len));426 ret = PTR_ERR_OR_ZERO(acl);427 if (ret)428 goto err;429 430 ret = allocate_dropping_locks_errcode(trans, __posix_acl_chmod(&acl, _gfp, mode));431 if (ret)432 goto err;433 434 struct bkey_i_xattr *new = bch2_acl_to_xattr(trans, acl, ACL_TYPE_ACCESS);435 ret = PTR_ERR_OR_ZERO(new);436 if (ret)437 goto err;438 439 new->k.p = iter.pos;440 ret = bch2_trans_update(trans, &iter, &new->k_i, 0);441 *new_acl = acl;442 acl = NULL;443err:444 bch2_trans_iter_exit(trans, &iter);445 if (!IS_ERR_OR_NULL(acl))446 kfree(acl);447 return ret;448}449 450#endif /* CONFIG_BCACHEFS_POSIX_ACL */451