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745 lines
19 KiB
745 lines
19 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* This file is part of UBIFS. |
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* |
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* Copyright (C) 2006-2008 Nokia Corporation. |
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* |
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* Authors: Artem Bityutskiy (Битюцкий Артём) |
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* Adrian Hunter |
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*/ |
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|
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/* |
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* This file implements UBIFS extended attributes support. |
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* |
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* Extended attributes are implemented as regular inodes with attached data, |
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* which limits extended attribute size to UBIFS block size (4KiB). Names of |
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* extended attributes are described by extended attribute entries (xentries), |
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* which are almost identical to directory entries, but have different key type. |
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* |
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* In other words, the situation with extended attributes is very similar to |
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* directories. Indeed, any inode (but of course not xattr inodes) may have a |
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* number of associated xentries, just like directory inodes have associated |
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* directory entries. Extended attribute entries store the name of the extended |
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* attribute, the host inode number, and the extended attribute inode number. |
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* Similarly, direntries store the name, the parent and the target inode |
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* numbers. Thus, most of the common UBIFS mechanisms may be re-used for |
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* extended attributes. |
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* |
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* The number of extended attributes is not limited, but there is Linux |
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* limitation on the maximum possible size of the list of all extended |
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* attributes associated with an inode (%XATTR_LIST_MAX), so UBIFS makes sure |
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* the sum of all extended attribute names of the inode does not exceed that |
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* limit. |
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* |
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* Extended attributes are synchronous, which means they are written to the |
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* flash media synchronously and there is no write-back for extended attribute |
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* inodes. The extended attribute values are not stored in compressed form on |
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* the media. |
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* |
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* Since extended attributes are represented by regular inodes, they are cached |
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* in the VFS inode cache. The xentries are cached in the LNC cache (see |
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* tnc.c). |
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* |
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* ACL support is not implemented. |
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*/ |
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|
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#include "ubifs.h" |
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#include <linux/fs.h> |
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#include <linux/slab.h> |
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#include <linux/xattr.h> |
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|
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/* |
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* Extended attribute type constants. |
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* |
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* USER_XATTR: user extended attribute ("user.*") |
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* TRUSTED_XATTR: trusted extended attribute ("trusted.*) |
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* SECURITY_XATTR: security extended attribute ("security.*") |
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*/ |
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enum { |
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USER_XATTR, |
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TRUSTED_XATTR, |
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SECURITY_XATTR, |
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}; |
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|
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static const struct inode_operations empty_iops; |
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static const struct file_operations empty_fops; |
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|
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/** |
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* create_xattr - create an extended attribute. |
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* @c: UBIFS file-system description object |
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* @host: host inode |
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* @nm: extended attribute name |
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* @value: extended attribute value |
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* @size: size of extended attribute value |
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* |
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* This is a helper function which creates an extended attribute of name @nm |
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* and value @value for inode @host. The host inode is also updated on flash |
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* because the ctime and extended attribute accounting data changes. This |
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* function returns zero in case of success and a negative error code in case |
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* of failure. |
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*/ |
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static int create_xattr(struct ubifs_info *c, struct inode *host, |
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const struct fscrypt_name *nm, const void *value, int size) |
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{ |
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int err, names_len; |
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struct inode *inode; |
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struct ubifs_inode *ui, *host_ui = ubifs_inode(host); |
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struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1, |
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.new_ino_d = ALIGN(size, 8), .dirtied_ino = 1, |
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.dirtied_ino_d = ALIGN(host_ui->data_len, 8) }; |
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|
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if (host_ui->xattr_cnt >= ubifs_xattr_max_cnt(c)) { |
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ubifs_err(c, "inode %lu already has too many xattrs (%d), cannot create more", |
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host->i_ino, host_ui->xattr_cnt); |
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return -ENOSPC; |
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} |
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/* |
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* Linux limits the maximum size of the extended attribute names list |
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* to %XATTR_LIST_MAX. This means we should not allow creating more |
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* extended attributes if the name list becomes larger. This limitation |
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* is artificial for UBIFS, though. |
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*/ |
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names_len = host_ui->xattr_names + host_ui->xattr_cnt + fname_len(nm) + 1; |
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if (names_len > XATTR_LIST_MAX) { |
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ubifs_err(c, "cannot add one more xattr name to inode %lu, total names length would become %d, max. is %d", |
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host->i_ino, names_len, XATTR_LIST_MAX); |
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return -ENOSPC; |
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} |
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|
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err = ubifs_budget_space(c, &req); |
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if (err) |
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return err; |
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|
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inode = ubifs_new_inode(c, host, S_IFREG | S_IRWXUGO); |
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if (IS_ERR(inode)) { |
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err = PTR_ERR(inode); |
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goto out_budg; |
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} |
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|
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/* Re-define all operations to be "nothing" */ |
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inode->i_mapping->a_ops = &empty_aops; |
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inode->i_op = &empty_iops; |
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inode->i_fop = &empty_fops; |
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|
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inode->i_flags |= S_SYNC | S_NOATIME | S_NOCMTIME; |
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ui = ubifs_inode(inode); |
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ui->xattr = 1; |
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ui->flags |= UBIFS_XATTR_FL; |
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ui->data = kmemdup(value, size, GFP_NOFS); |
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if (!ui->data) { |
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err = -ENOMEM; |
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goto out_free; |
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} |
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inode->i_size = ui->ui_size = size; |
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ui->data_len = size; |
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|
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mutex_lock(&host_ui->ui_mutex); |
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host->i_ctime = current_time(host); |
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host_ui->xattr_cnt += 1; |
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host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm)); |
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host_ui->xattr_size += CALC_XATTR_BYTES(size); |
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host_ui->xattr_names += fname_len(nm); |
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|
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/* |
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* We handle UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT here because we |
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* have to set the UBIFS_CRYPT_FL flag on the host inode. |
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* To avoid multiple updates of the same inode in the same operation, |
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* let's do it here. |
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*/ |
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if (strcmp(fname_name(nm), UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT) == 0) |
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host_ui->flags |= UBIFS_CRYPT_FL; |
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|
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err = ubifs_jnl_update(c, host, nm, inode, 0, 1); |
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if (err) |
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goto out_cancel; |
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ubifs_set_inode_flags(host); |
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mutex_unlock(&host_ui->ui_mutex); |
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|
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ubifs_release_budget(c, &req); |
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insert_inode_hash(inode); |
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iput(inode); |
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return 0; |
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out_cancel: |
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host_ui->xattr_cnt -= 1; |
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host_ui->xattr_size -= CALC_DENT_SIZE(fname_len(nm)); |
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host_ui->xattr_size -= CALC_XATTR_BYTES(size); |
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host_ui->xattr_names -= fname_len(nm); |
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host_ui->flags &= ~UBIFS_CRYPT_FL; |
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mutex_unlock(&host_ui->ui_mutex); |
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out_free: |
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make_bad_inode(inode); |
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iput(inode); |
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out_budg: |
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ubifs_release_budget(c, &req); |
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return err; |
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} |
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|
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/** |
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* change_xattr - change an extended attribute. |
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* @c: UBIFS file-system description object |
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* @host: host inode |
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* @inode: extended attribute inode |
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* @value: extended attribute value |
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* @size: size of extended attribute value |
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* |
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* This helper function changes the value of extended attribute @inode with new |
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* data from @value. Returns zero in case of success and a negative error code |
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* in case of failure. |
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*/ |
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static int change_xattr(struct ubifs_info *c, struct inode *host, |
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struct inode *inode, const void *value, int size) |
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{ |
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int err; |
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struct ubifs_inode *host_ui = ubifs_inode(host); |
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struct ubifs_inode *ui = ubifs_inode(inode); |
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void *buf = NULL; |
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int old_size; |
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struct ubifs_budget_req req = { .dirtied_ino = 2, |
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.dirtied_ino_d = ALIGN(size, 8) + ALIGN(host_ui->data_len, 8) }; |
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|
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ubifs_assert(c, ui->data_len == inode->i_size); |
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err = ubifs_budget_space(c, &req); |
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if (err) |
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return err; |
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|
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buf = kmemdup(value, size, GFP_NOFS); |
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if (!buf) { |
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err = -ENOMEM; |
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goto out_free; |
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} |
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kfree(ui->data); |
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ui->data = buf; |
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inode->i_size = ui->ui_size = size; |
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old_size = ui->data_len; |
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ui->data_len = size; |
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|
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mutex_lock(&host_ui->ui_mutex); |
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host->i_ctime = current_time(host); |
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host_ui->xattr_size -= CALC_XATTR_BYTES(old_size); |
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host_ui->xattr_size += CALC_XATTR_BYTES(size); |
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|
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/* |
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* It is important to write the host inode after the xattr inode |
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* because if the host inode gets synchronized (via 'fsync()'), then |
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* the extended attribute inode gets synchronized, because it goes |
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* before the host inode in the write-buffer. |
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*/ |
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err = ubifs_jnl_change_xattr(c, inode, host); |
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if (err) |
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goto out_cancel; |
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mutex_unlock(&host_ui->ui_mutex); |
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ubifs_release_budget(c, &req); |
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return 0; |
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out_cancel: |
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host_ui->xattr_size -= CALC_XATTR_BYTES(size); |
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host_ui->xattr_size += CALC_XATTR_BYTES(old_size); |
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mutex_unlock(&host_ui->ui_mutex); |
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make_bad_inode(inode); |
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out_free: |
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ubifs_release_budget(c, &req); |
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return err; |
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} |
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static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum) |
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{ |
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struct inode *inode; |
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inode = ubifs_iget(c->vfs_sb, inum); |
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if (IS_ERR(inode)) { |
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ubifs_err(c, "dead extended attribute entry, error %d", |
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(int)PTR_ERR(inode)); |
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return inode; |
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} |
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if (ubifs_inode(inode)->xattr) |
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return inode; |
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ubifs_err(c, "corrupt extended attribute entry"); |
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iput(inode); |
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return ERR_PTR(-EINVAL); |
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} |
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int ubifs_xattr_set(struct inode *host, const char *name, const void *value, |
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size_t size, int flags, bool check_lock) |
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{ |
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struct inode *inode; |
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struct ubifs_info *c = host->i_sb->s_fs_info; |
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struct fscrypt_name nm = { .disk_name = FSTR_INIT((char *)name, strlen(name))}; |
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struct ubifs_dent_node *xent; |
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union ubifs_key key; |
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int err; |
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if (check_lock) |
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ubifs_assert(c, inode_is_locked(host)); |
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if (size > UBIFS_MAX_INO_DATA) |
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return -ERANGE; |
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if (fname_len(&nm) > UBIFS_MAX_NLEN) |
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return -ENAMETOOLONG; |
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xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); |
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if (!xent) |
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return -ENOMEM; |
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|
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down_write(&ubifs_inode(host)->xattr_sem); |
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/* |
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* The extended attribute entries are stored in LNC, so multiple |
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* look-ups do not involve reading the flash. |
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*/ |
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xent_key_init(c, &key, host->i_ino, &nm); |
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err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); |
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if (err) { |
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if (err != -ENOENT) |
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goto out_free; |
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|
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if (flags & XATTR_REPLACE) |
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/* We are asked not to create the xattr */ |
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err = -ENODATA; |
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else |
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err = create_xattr(c, host, &nm, value, size); |
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goto out_free; |
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} |
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if (flags & XATTR_CREATE) { |
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/* We are asked not to replace the xattr */ |
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err = -EEXIST; |
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goto out_free; |
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} |
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inode = iget_xattr(c, le64_to_cpu(xent->inum)); |
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if (IS_ERR(inode)) { |
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err = PTR_ERR(inode); |
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goto out_free; |
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} |
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err = change_xattr(c, host, inode, value, size); |
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iput(inode); |
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|
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out_free: |
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up_write(&ubifs_inode(host)->xattr_sem); |
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kfree(xent); |
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return err; |
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} |
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ssize_t ubifs_xattr_get(struct inode *host, const char *name, void *buf, |
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size_t size) |
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{ |
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struct inode *inode; |
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struct ubifs_info *c = host->i_sb->s_fs_info; |
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struct fscrypt_name nm = { .disk_name = FSTR_INIT((char *)name, strlen(name))}; |
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struct ubifs_inode *ui; |
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struct ubifs_dent_node *xent; |
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union ubifs_key key; |
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int err; |
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|
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if (fname_len(&nm) > UBIFS_MAX_NLEN) |
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return -ENAMETOOLONG; |
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|
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xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); |
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if (!xent) |
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return -ENOMEM; |
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|
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down_read(&ubifs_inode(host)->xattr_sem); |
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xent_key_init(c, &key, host->i_ino, &nm); |
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err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); |
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if (err) { |
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if (err == -ENOENT) |
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err = -ENODATA; |
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goto out_cleanup; |
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} |
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inode = iget_xattr(c, le64_to_cpu(xent->inum)); |
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if (IS_ERR(inode)) { |
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err = PTR_ERR(inode); |
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goto out_cleanup; |
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} |
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|
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ui = ubifs_inode(inode); |
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ubifs_assert(c, inode->i_size == ui->data_len); |
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ubifs_assert(c, ubifs_inode(host)->xattr_size > ui->data_len); |
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|
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if (buf) { |
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/* If @buf is %NULL we are supposed to return the length */ |
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if (ui->data_len > size) { |
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err = -ERANGE; |
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goto out_iput; |
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} |
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|
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memcpy(buf, ui->data, ui->data_len); |
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} |
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err = ui->data_len; |
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|
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out_iput: |
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iput(inode); |
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out_cleanup: |
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up_read(&ubifs_inode(host)->xattr_sem); |
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kfree(xent); |
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return err; |
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} |
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static bool xattr_visible(const char *name) |
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{ |
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/* File encryption related xattrs are for internal use only */ |
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if (strcmp(name, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT) == 0) |
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return false; |
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|
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/* Show trusted namespace only for "power" users */ |
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if (strncmp(name, XATTR_TRUSTED_PREFIX, |
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XATTR_TRUSTED_PREFIX_LEN) == 0 && !capable(CAP_SYS_ADMIN)) |
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return false; |
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|
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return true; |
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} |
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ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size) |
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{ |
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union ubifs_key key; |
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struct inode *host = d_inode(dentry); |
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struct ubifs_info *c = host->i_sb->s_fs_info; |
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struct ubifs_inode *host_ui = ubifs_inode(host); |
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struct ubifs_dent_node *xent, *pxent = NULL; |
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int err, len, written = 0; |
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struct fscrypt_name nm = {0}; |
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|
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dbg_gen("ino %lu ('%pd'), buffer size %zd", host->i_ino, |
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dentry, size); |
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|
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down_read(&host_ui->xattr_sem); |
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len = host_ui->xattr_names + host_ui->xattr_cnt; |
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if (!buffer) { |
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/* |
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* We should return the minimum buffer size which will fit a |
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* null-terminated list of all the extended attribute names. |
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*/ |
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err = len; |
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goto out_err; |
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} |
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|
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if (len > size) { |
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err = -ERANGE; |
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goto out_err; |
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} |
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|
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lowest_xent_key(c, &key, host->i_ino); |
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while (1) { |
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xent = ubifs_tnc_next_ent(c, &key, &nm); |
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if (IS_ERR(xent)) { |
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err = PTR_ERR(xent); |
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break; |
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} |
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|
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fname_name(&nm) = xent->name; |
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fname_len(&nm) = le16_to_cpu(xent->nlen); |
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|
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if (xattr_visible(xent->name)) { |
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memcpy(buffer + written, fname_name(&nm), fname_len(&nm) + 1); |
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written += fname_len(&nm) + 1; |
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} |
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|
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kfree(pxent); |
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pxent = xent; |
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key_read(c, &xent->key, &key); |
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} |
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kfree(pxent); |
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up_read(&host_ui->xattr_sem); |
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|
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if (err != -ENOENT) { |
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ubifs_err(c, "cannot find next direntry, error %d", err); |
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return err; |
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} |
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|
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ubifs_assert(c, written <= size); |
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return written; |
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|
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out_err: |
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up_read(&host_ui->xattr_sem); |
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return err; |
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} |
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|
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static int remove_xattr(struct ubifs_info *c, struct inode *host, |
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struct inode *inode, const struct fscrypt_name *nm) |
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{ |
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int err; |
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struct ubifs_inode *host_ui = ubifs_inode(host); |
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struct ubifs_inode *ui = ubifs_inode(inode); |
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struct ubifs_budget_req req = { .dirtied_ino = 2, .mod_dent = 1, |
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.dirtied_ino_d = ALIGN(host_ui->data_len, 8) }; |
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|
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ubifs_assert(c, ui->data_len == inode->i_size); |
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|
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err = ubifs_budget_space(c, &req); |
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if (err) |
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return err; |
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|
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mutex_lock(&host_ui->ui_mutex); |
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host->i_ctime = current_time(host); |
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host_ui->xattr_cnt -= 1; |
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host_ui->xattr_size -= CALC_DENT_SIZE(fname_len(nm)); |
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host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len); |
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host_ui->xattr_names -= fname_len(nm); |
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|
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err = ubifs_jnl_delete_xattr(c, host, inode, nm); |
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if (err) |
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goto out_cancel; |
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mutex_unlock(&host_ui->ui_mutex); |
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|
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ubifs_release_budget(c, &req); |
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return 0; |
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|
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out_cancel: |
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host_ui->xattr_cnt += 1; |
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host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm)); |
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host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len); |
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host_ui->xattr_names += fname_len(nm); |
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mutex_unlock(&host_ui->ui_mutex); |
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ubifs_release_budget(c, &req); |
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make_bad_inode(inode); |
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return err; |
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} |
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|
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int ubifs_purge_xattrs(struct inode *host) |
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{ |
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union ubifs_key key; |
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struct ubifs_info *c = host->i_sb->s_fs_info; |
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struct ubifs_dent_node *xent, *pxent = NULL; |
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struct inode *xino; |
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struct fscrypt_name nm = {0}; |
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int err; |
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|
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if (ubifs_inode(host)->xattr_cnt <= ubifs_xattr_max_cnt(c)) |
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return 0; |
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|
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ubifs_warn(c, "inode %lu has too many xattrs, doing a non-atomic deletion", |
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host->i_ino); |
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|
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down_write(&ubifs_inode(host)->xattr_sem); |
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lowest_xent_key(c, &key, host->i_ino); |
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while (1) { |
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xent = ubifs_tnc_next_ent(c, &key, &nm); |
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if (IS_ERR(xent)) { |
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err = PTR_ERR(xent); |
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break; |
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} |
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|
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fname_name(&nm) = xent->name; |
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fname_len(&nm) = le16_to_cpu(xent->nlen); |
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|
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xino = ubifs_iget(c->vfs_sb, le64_to_cpu(xent->inum)); |
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if (IS_ERR(xino)) { |
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err = PTR_ERR(xino); |
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ubifs_err(c, "dead directory entry '%s', error %d", |
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xent->name, err); |
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ubifs_ro_mode(c, err); |
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kfree(pxent); |
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kfree(xent); |
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goto out_err; |
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} |
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|
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ubifs_assert(c, ubifs_inode(xino)->xattr); |
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|
|
clear_nlink(xino); |
|
err = remove_xattr(c, host, xino, &nm); |
|
if (err) { |
|
kfree(pxent); |
|
kfree(xent); |
|
iput(xino); |
|
ubifs_err(c, "cannot remove xattr, error %d", err); |
|
goto out_err; |
|
} |
|
|
|
iput(xino); |
|
|
|
kfree(pxent); |
|
pxent = xent; |
|
key_read(c, &xent->key, &key); |
|
} |
|
kfree(pxent); |
|
up_write(&ubifs_inode(host)->xattr_sem); |
|
|
|
if (err != -ENOENT) { |
|
ubifs_err(c, "cannot find next direntry, error %d", err); |
|
return err; |
|
} |
|
|
|
return 0; |
|
|
|
out_err: |
|
up_write(&ubifs_inode(host)->xattr_sem); |
|
return err; |
|
} |
|
|
|
/** |
|
* ubifs_evict_xattr_inode - Evict an xattr inode. |
|
* @c: UBIFS file-system description object |
|
* @xattr_inum: xattr inode number |
|
* |
|
* When an inode that hosts xattrs is being removed we have to make sure |
|
* that cached inodes of the xattrs also get removed from the inode cache |
|
* otherwise we'd waste memory. This function looks up an inode from the |
|
* inode cache and clears the link counter such that iput() will evict |
|
* the inode. |
|
*/ |
|
void ubifs_evict_xattr_inode(struct ubifs_info *c, ino_t xattr_inum) |
|
{ |
|
struct inode *inode; |
|
|
|
inode = ilookup(c->vfs_sb, xattr_inum); |
|
if (inode) { |
|
clear_nlink(inode); |
|
iput(inode); |
|
} |
|
} |
|
|
|
static int ubifs_xattr_remove(struct inode *host, const char *name) |
|
{ |
|
struct inode *inode; |
|
struct ubifs_info *c = host->i_sb->s_fs_info; |
|
struct fscrypt_name nm = { .disk_name = FSTR_INIT((char *)name, strlen(name))}; |
|
struct ubifs_dent_node *xent; |
|
union ubifs_key key; |
|
int err; |
|
|
|
ubifs_assert(c, inode_is_locked(host)); |
|
|
|
if (fname_len(&nm) > UBIFS_MAX_NLEN) |
|
return -ENAMETOOLONG; |
|
|
|
xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); |
|
if (!xent) |
|
return -ENOMEM; |
|
|
|
down_write(&ubifs_inode(host)->xattr_sem); |
|
xent_key_init(c, &key, host->i_ino, &nm); |
|
err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); |
|
if (err) { |
|
if (err == -ENOENT) |
|
err = -ENODATA; |
|
goto out_free; |
|
} |
|
|
|
inode = iget_xattr(c, le64_to_cpu(xent->inum)); |
|
if (IS_ERR(inode)) { |
|
err = PTR_ERR(inode); |
|
goto out_free; |
|
} |
|
|
|
ubifs_assert(c, inode->i_nlink == 1); |
|
clear_nlink(inode); |
|
err = remove_xattr(c, host, inode, &nm); |
|
if (err) |
|
set_nlink(inode, 1); |
|
|
|
/* If @i_nlink is 0, 'iput()' will delete the inode */ |
|
iput(inode); |
|
|
|
out_free: |
|
up_write(&ubifs_inode(host)->xattr_sem); |
|
kfree(xent); |
|
return err; |
|
} |
|
|
|
#ifdef CONFIG_UBIFS_FS_SECURITY |
|
static int init_xattrs(struct inode *inode, const struct xattr *xattr_array, |
|
void *fs_info) |
|
{ |
|
const struct xattr *xattr; |
|
char *name; |
|
int err = 0; |
|
|
|
for (xattr = xattr_array; xattr->name != NULL; xattr++) { |
|
name = kmalloc(XATTR_SECURITY_PREFIX_LEN + |
|
strlen(xattr->name) + 1, GFP_NOFS); |
|
if (!name) { |
|
err = -ENOMEM; |
|
break; |
|
} |
|
strcpy(name, XATTR_SECURITY_PREFIX); |
|
strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name); |
|
/* |
|
* creating a new inode without holding the inode rwsem, |
|
* no need to check whether inode is locked. |
|
*/ |
|
err = ubifs_xattr_set(inode, name, xattr->value, |
|
xattr->value_len, 0, false); |
|
kfree(name); |
|
if (err < 0) |
|
break; |
|
} |
|
|
|
return err; |
|
} |
|
|
|
int ubifs_init_security(struct inode *dentry, struct inode *inode, |
|
const struct qstr *qstr) |
|
{ |
|
int err; |
|
|
|
err = security_inode_init_security(inode, dentry, qstr, |
|
&init_xattrs, 0); |
|
if (err) { |
|
struct ubifs_info *c = dentry->i_sb->s_fs_info; |
|
ubifs_err(c, "cannot initialize security for inode %lu, error %d", |
|
inode->i_ino, err); |
|
} |
|
return err; |
|
} |
|
#endif |
|
|
|
static int xattr_get(const struct xattr_handler *handler, |
|
struct dentry *dentry, struct inode *inode, |
|
const char *name, void *buffer, size_t size) |
|
{ |
|
dbg_gen("xattr '%s', ino %lu ('%pd'), buf size %zd", name, |
|
inode->i_ino, dentry, size); |
|
|
|
name = xattr_full_name(handler, name); |
|
return ubifs_xattr_get(inode, name, buffer, size); |
|
} |
|
|
|
static int xattr_set(const struct xattr_handler *handler, |
|
struct user_namespace *mnt_userns, |
|
struct dentry *dentry, struct inode *inode, |
|
const char *name, const void *value, |
|
size_t size, int flags) |
|
{ |
|
dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd", |
|
name, inode->i_ino, dentry, size); |
|
|
|
name = xattr_full_name(handler, name); |
|
|
|
if (value) |
|
return ubifs_xattr_set(inode, name, value, size, flags, true); |
|
else |
|
return ubifs_xattr_remove(inode, name); |
|
} |
|
|
|
static const struct xattr_handler ubifs_user_xattr_handler = { |
|
.prefix = XATTR_USER_PREFIX, |
|
.get = xattr_get, |
|
.set = xattr_set, |
|
}; |
|
|
|
static const struct xattr_handler ubifs_trusted_xattr_handler = { |
|
.prefix = XATTR_TRUSTED_PREFIX, |
|
.get = xattr_get, |
|
.set = xattr_set, |
|
}; |
|
|
|
#ifdef CONFIG_UBIFS_FS_SECURITY |
|
static const struct xattr_handler ubifs_security_xattr_handler = { |
|
.prefix = XATTR_SECURITY_PREFIX, |
|
.get = xattr_get, |
|
.set = xattr_set, |
|
}; |
|
#endif |
|
|
|
const struct xattr_handler *ubifs_xattr_handlers[] = { |
|
&ubifs_user_xattr_handler, |
|
&ubifs_trusted_xattr_handler, |
|
#ifdef CONFIG_UBIFS_FS_SECURITY |
|
&ubifs_security_xattr_handler, |
|
#endif |
|
NULL |
|
};
|
|
|