| // SPDX-License-Identifier: GPL-2.0 |
| |
| #include "bcachefs.h" |
| |
| #include "acl.h" |
| #include "xattr.h" |
| |
| #include <linux/posix_acl.h> |
| |
| static const char * const acl_types[] = { |
| [ACL_USER_OBJ] = "user_obj", |
| [ACL_USER] = "user", |
| [ACL_GROUP_OBJ] = "group_obj", |
| [ACL_GROUP] = "group", |
| [ACL_MASK] = "mask", |
| [ACL_OTHER] = "other", |
| NULL, |
| }; |
| |
| void bch2_acl_to_text(struct printbuf *out, const void *value, size_t size) |
| { |
| const void *p, *end = value + size; |
| |
| if (!value || |
| size < sizeof(bch_acl_header) || |
| ((bch_acl_header *)value)->a_version != cpu_to_le32(BCH_ACL_VERSION)) |
| return; |
| |
| p = value + sizeof(bch_acl_header); |
| while (p < end) { |
| const bch_acl_entry *in = p; |
| unsigned tag = le16_to_cpu(in->e_tag); |
| |
| prt_str(out, acl_types[tag]); |
| |
| switch (tag) { |
| case ACL_USER_OBJ: |
| case ACL_GROUP_OBJ: |
| case ACL_MASK: |
| case ACL_OTHER: |
| p += sizeof(bch_acl_entry_short); |
| break; |
| case ACL_USER: |
| prt_printf(out, " uid %u", le32_to_cpu(in->e_id)); |
| p += sizeof(bch_acl_entry); |
| break; |
| case ACL_GROUP: |
| prt_printf(out, " gid %u", le32_to_cpu(in->e_id)); |
| p += sizeof(bch_acl_entry); |
| break; |
| } |
| |
| prt_printf(out, " %o", le16_to_cpu(in->e_perm)); |
| |
| if (p != end) |
| prt_char(out, ' '); |
| } |
| } |
| |
| #ifdef CONFIG_BCACHEFS_POSIX_ACL |
| |
| #include "fs.h" |
| |
| #include <linux/fs.h> |
| #include <linux/posix_acl_xattr.h> |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| |
| static inline size_t bch2_acl_size(unsigned nr_short, unsigned nr_long) |
| { |
| return sizeof(bch_acl_header) + |
| sizeof(bch_acl_entry_short) * nr_short + |
| sizeof(bch_acl_entry) * nr_long; |
| } |
| |
| static inline int acl_to_xattr_type(int type) |
| { |
| switch (type) { |
| case ACL_TYPE_ACCESS: |
| return KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS; |
| case ACL_TYPE_DEFAULT: |
| return KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT; |
| default: |
| BUG(); |
| } |
| } |
| |
| /* |
| * Convert from filesystem to in-memory representation. |
| */ |
| static struct posix_acl *bch2_acl_from_disk(struct btree_trans *trans, |
| const void *value, size_t size) |
| { |
| const void *p, *end = value + size; |
| struct posix_acl *acl; |
| struct posix_acl_entry *out; |
| unsigned count = 0; |
| int ret; |
| |
| if (!value) |
| return NULL; |
| if (size < sizeof(bch_acl_header)) |
| goto invalid; |
| if (((bch_acl_header *)value)->a_version != |
| cpu_to_le32(BCH_ACL_VERSION)) |
| goto invalid; |
| |
| p = value + sizeof(bch_acl_header); |
| while (p < end) { |
| const bch_acl_entry *entry = p; |
| |
| if (p + sizeof(bch_acl_entry_short) > end) |
| goto invalid; |
| |
| switch (le16_to_cpu(entry->e_tag)) { |
| case ACL_USER_OBJ: |
| case ACL_GROUP_OBJ: |
| case ACL_MASK: |
| case ACL_OTHER: |
| p += sizeof(bch_acl_entry_short); |
| break; |
| case ACL_USER: |
| case ACL_GROUP: |
| p += sizeof(bch_acl_entry); |
| break; |
| default: |
| goto invalid; |
| } |
| |
| count++; |
| } |
| |
| if (p > end) |
| goto invalid; |
| |
| if (!count) |
| return NULL; |
| |
| acl = allocate_dropping_locks(trans, ret, |
| posix_acl_alloc(count, _gfp)); |
| if (!acl) |
| return ERR_PTR(-ENOMEM); |
| if (ret) { |
| kfree(acl); |
| return ERR_PTR(ret); |
| } |
| |
| out = acl->a_entries; |
| |
| p = value + sizeof(bch_acl_header); |
| while (p < end) { |
| const bch_acl_entry *in = p; |
| |
| out->e_tag = le16_to_cpu(in->e_tag); |
| out->e_perm = le16_to_cpu(in->e_perm); |
| |
| switch (out->e_tag) { |
| case ACL_USER_OBJ: |
| case ACL_GROUP_OBJ: |
| case ACL_MASK: |
| case ACL_OTHER: |
| p += sizeof(bch_acl_entry_short); |
| break; |
| case ACL_USER: |
| out->e_uid = make_kuid(&init_user_ns, |
| le32_to_cpu(in->e_id)); |
| p += sizeof(bch_acl_entry); |
| break; |
| case ACL_GROUP: |
| out->e_gid = make_kgid(&init_user_ns, |
| le32_to_cpu(in->e_id)); |
| p += sizeof(bch_acl_entry); |
| break; |
| } |
| |
| out++; |
| } |
| |
| BUG_ON(out != acl->a_entries + acl->a_count); |
| |
| return acl; |
| invalid: |
| pr_err("invalid acl entry"); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| #define acl_for_each_entry(acl, acl_e) \ |
| for (acl_e = acl->a_entries; \ |
| acl_e < acl->a_entries + acl->a_count; \ |
| acl_e++) |
| |
| /* |
| * Convert from in-memory to filesystem representation. |
| */ |
| static struct bkey_i_xattr * |
| bch2_acl_to_xattr(struct btree_trans *trans, |
| const struct posix_acl *acl, |
| int type) |
| { |
| struct bkey_i_xattr *xattr; |
| bch_acl_header *acl_header; |
| const struct posix_acl_entry *acl_e; |
| void *outptr; |
| unsigned nr_short = 0, nr_long = 0, acl_len, u64s; |
| |
| acl_for_each_entry(acl, acl_e) { |
| switch (acl_e->e_tag) { |
| case ACL_USER: |
| case ACL_GROUP: |
| nr_long++; |
| break; |
| case ACL_USER_OBJ: |
| case ACL_GROUP_OBJ: |
| case ACL_MASK: |
| case ACL_OTHER: |
| nr_short++; |
| break; |
| default: |
| return ERR_PTR(-EINVAL); |
| } |
| } |
| |
| acl_len = bch2_acl_size(nr_short, nr_long); |
| u64s = BKEY_U64s + xattr_val_u64s(0, acl_len); |
| |
| if (u64s > U8_MAX) |
| return ERR_PTR(-E2BIG); |
| |
| xattr = bch2_trans_kmalloc(trans, u64s * sizeof(u64)); |
| if (IS_ERR(xattr)) |
| return xattr; |
| |
| bkey_xattr_init(&xattr->k_i); |
| xattr->k.u64s = u64s; |
| xattr->v.x_type = acl_to_xattr_type(type); |
| xattr->v.x_name_len = 0; |
| xattr->v.x_val_len = cpu_to_le16(acl_len); |
| |
| acl_header = xattr_val(&xattr->v); |
| acl_header->a_version = cpu_to_le32(BCH_ACL_VERSION); |
| |
| outptr = (void *) acl_header + sizeof(*acl_header); |
| |
| acl_for_each_entry(acl, acl_e) { |
| bch_acl_entry *entry = outptr; |
| |
| entry->e_tag = cpu_to_le16(acl_e->e_tag); |
| entry->e_perm = cpu_to_le16(acl_e->e_perm); |
| switch (acl_e->e_tag) { |
| case ACL_USER: |
| entry->e_id = cpu_to_le32( |
| from_kuid(&init_user_ns, acl_e->e_uid)); |
| outptr += sizeof(bch_acl_entry); |
| break; |
| case ACL_GROUP: |
| entry->e_id = cpu_to_le32( |
| from_kgid(&init_user_ns, acl_e->e_gid)); |
| outptr += sizeof(bch_acl_entry); |
| break; |
| |
| case ACL_USER_OBJ: |
| case ACL_GROUP_OBJ: |
| case ACL_MASK: |
| case ACL_OTHER: |
| outptr += sizeof(bch_acl_entry_short); |
| break; |
| } |
| } |
| |
| BUG_ON(outptr != xattr_val(&xattr->v) + acl_len); |
| |
| return xattr; |
| } |
| |
| struct posix_acl *bch2_get_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, int type) |
| { |
| struct bch_inode_info *inode = to_bch_ei(dentry->d_inode); |
| struct bch_fs *c = inode->v.i_sb->s_fs_info; |
| struct bch_hash_info hash = bch2_hash_info_init(c, &inode->ei_inode); |
| struct xattr_search_key search = X_SEARCH(acl_to_xattr_type(type), "", 0); |
| struct btree_trans *trans = bch2_trans_get(c); |
| struct btree_iter iter = { NULL }; |
| struct posix_acl *acl = NULL; |
| retry: |
| bch2_trans_begin(trans); |
| |
| struct bkey_s_c k = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc, |
| &hash, inode_inum(inode), &search, 0); |
| int ret = bkey_err(k); |
| if (ret) |
| goto err; |
| |
| struct bkey_s_c_xattr xattr = bkey_s_c_to_xattr(k); |
| acl = bch2_acl_from_disk(trans, xattr_val(xattr.v), |
| le16_to_cpu(xattr.v->x_val_len)); |
| ret = PTR_ERR_OR_ZERO(acl); |
| err: |
| if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) |
| goto retry; |
| |
| if (ret) |
| acl = !bch2_err_matches(ret, ENOENT) ? ERR_PTR(ret) : NULL; |
| |
| if (!IS_ERR_OR_NULL(acl)) |
| set_cached_acl(&inode->v, type, acl); |
| |
| bch2_trans_iter_exit(trans, &iter); |
| bch2_trans_put(trans); |
| return acl; |
| } |
| |
| int bch2_set_acl_trans(struct btree_trans *trans, subvol_inum inum, |
| struct bch_inode_unpacked *inode_u, |
| struct posix_acl *acl, int type) |
| { |
| struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode_u); |
| int ret; |
| |
| if (type == ACL_TYPE_DEFAULT && |
| !S_ISDIR(inode_u->bi_mode)) |
| return acl ? -EACCES : 0; |
| |
| if (acl) { |
| struct bkey_i_xattr *xattr = |
| bch2_acl_to_xattr(trans, acl, type); |
| if (IS_ERR(xattr)) |
| return PTR_ERR(xattr); |
| |
| ret = bch2_hash_set(trans, bch2_xattr_hash_desc, &hash_info, |
| inum, &xattr->k_i, 0); |
| } else { |
| struct xattr_search_key search = |
| X_SEARCH(acl_to_xattr_type(type), "", 0); |
| |
| ret = bch2_hash_delete(trans, bch2_xattr_hash_desc, &hash_info, |
| inum, &search); |
| } |
| |
| return bch2_err_matches(ret, ENOENT) ? 0 : ret; |
| } |
| |
| int bch2_set_acl(struct mnt_idmap *idmap, |
| struct dentry *dentry, |
| struct posix_acl *_acl, int type) |
| { |
| struct bch_inode_info *inode = to_bch_ei(dentry->d_inode); |
| struct bch_fs *c = inode->v.i_sb->s_fs_info; |
| struct btree_trans *trans = bch2_trans_get(c); |
| struct btree_iter inode_iter = { NULL }; |
| struct bch_inode_unpacked inode_u; |
| struct posix_acl *acl; |
| umode_t mode; |
| int ret; |
| |
| mutex_lock(&inode->ei_update_lock); |
| retry: |
| bch2_trans_begin(trans); |
| acl = _acl; |
| |
| ret = bch2_subvol_is_ro_trans(trans, inode->ei_subvol) ?: |
| bch2_inode_peek(trans, &inode_iter, &inode_u, inode_inum(inode), |
| BTREE_ITER_intent); |
| if (ret) |
| goto btree_err; |
| |
| mode = inode_u.bi_mode; |
| |
| if (type == ACL_TYPE_ACCESS) { |
| ret = posix_acl_update_mode(idmap, &inode->v, &mode, &acl); |
| if (ret) |
| goto btree_err; |
| } |
| |
| ret = bch2_set_acl_trans(trans, inode_inum(inode), &inode_u, acl, type); |
| if (ret) |
| goto btree_err; |
| |
| inode_u.bi_ctime = bch2_current_time(c); |
| inode_u.bi_mode = mode; |
| |
| ret = bch2_inode_write(trans, &inode_iter, &inode_u) ?: |
| bch2_trans_commit(trans, NULL, NULL, 0); |
| btree_err: |
| bch2_trans_iter_exit(trans, &inode_iter); |
| |
| if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) |
| goto retry; |
| if (unlikely(ret)) |
| goto err; |
| |
| bch2_inode_update_after_write(trans, inode, &inode_u, |
| ATTR_CTIME|ATTR_MODE); |
| |
| set_cached_acl(&inode->v, type, acl); |
| err: |
| mutex_unlock(&inode->ei_update_lock); |
| bch2_trans_put(trans); |
| |
| return ret; |
| } |
| |
| int bch2_acl_chmod(struct btree_trans *trans, subvol_inum inum, |
| struct bch_inode_unpacked *inode, |
| umode_t mode, |
| struct posix_acl **new_acl) |
| { |
| struct bch_hash_info hash_info = bch2_hash_info_init(trans->c, inode); |
| struct xattr_search_key search = X_SEARCH(KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS, "", 0); |
| struct btree_iter iter; |
| struct posix_acl *acl = NULL; |
| |
| struct bkey_s_c k = bch2_hash_lookup(trans, &iter, bch2_xattr_hash_desc, |
| &hash_info, inum, &search, BTREE_ITER_intent); |
| int ret = bkey_err(k); |
| if (ret) |
| return bch2_err_matches(ret, ENOENT) ? 0 : ret; |
| |
| struct bkey_s_c_xattr xattr = bkey_s_c_to_xattr(k); |
| |
| acl = bch2_acl_from_disk(trans, xattr_val(xattr.v), |
| le16_to_cpu(xattr.v->x_val_len)); |
| ret = PTR_ERR_OR_ZERO(acl); |
| if (ret) |
| goto err; |
| |
| ret = allocate_dropping_locks_errcode(trans, __posix_acl_chmod(&acl, _gfp, mode)); |
| if (ret) |
| goto err; |
| |
| struct bkey_i_xattr *new = bch2_acl_to_xattr(trans, acl, ACL_TYPE_ACCESS); |
| ret = PTR_ERR_OR_ZERO(new); |
| if (ret) |
| goto err; |
| |
| new->k.p = iter.pos; |
| ret = bch2_trans_update(trans, &iter, &new->k_i, 0); |
| *new_acl = acl; |
| acl = NULL; |
| err: |
| bch2_trans_iter_exit(trans, &iter); |
| if (!IS_ERR_OR_NULL(acl)) |
| kfree(acl); |
| return ret; |
| } |
| |
| #endif /* CONFIG_BCACHEFS_POSIX_ACL */ |