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![Xiaolei Li](/assets/img/avatar_default.png)
The inode is not locked in init_xattrs when creating a new inode. Without this patch, there will occurs assert when booting or creating a new file, if the kernel config CONFIG_SECURITY_SMACK is enabled. Log likes: UBIFS assert failed in ubifs_xattr_set at 298 (pid 1156) CPU: 1 PID: 1156 Comm: ldconfig Tainted: G S 4.12.0-rc1-207440-g1e70b02 #2 Hardware name: MediaTek MT2712 evaluation board (DT) Call trace: [<ffff000008088538>] dump_backtrace+0x0/0x238 [<ffff000008088834>] show_stack+0x14/0x20 [<ffff0000083d98d4>] dump_stack+0x9c/0xc0 [<ffff00000835d524>] ubifs_xattr_set+0x374/0x5e0 [<ffff00000835d7ec>] init_xattrs+0x5c/0xb8 [<ffff000008385788>] security_inode_init_security+0x110/0x190 [<ffff00000835e058>] ubifs_init_security+0x30/0x68 [<ffff00000833ada0>] ubifs_mkdir+0x100/0x200 [<ffff00000820669c>] vfs_mkdir+0x11c/0x1b8 [<ffff00000820b73c>] SyS_mkdirat+0x74/0xd0 [<ffff000008082f8c>] __sys_trace_return+0x0/0x4 Signed-off-by: Xiaolei Li <xiaolei.li@mediatek.com> Signed-off-by: Richard Weinberger <richard@nod.at>
680 lines
18 KiB
C
680 lines
18 KiB
C
/*
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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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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 as published by
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* the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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* more details.
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*
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* You should have received a copy of the GNU General Public License along with
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* this program; if not, write to the Free Software Foundation, Inc., 51
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* Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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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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* 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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#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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* Limit the number of extended attributes per inode so that the total size
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* (@xattr_size) is guaranteeded to fit in an 'unsigned int'.
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*/
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#define MAX_XATTRS_PER_INODE 65535
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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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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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* 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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if (host_ui->xattr_cnt >= MAX_XATTRS_PER_INODE) {
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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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err = ubifs_budget_space(c, &req);
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if (err)
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return err;
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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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/* 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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inode->i_flags |= S_SYNC | S_NOATIME | S_NOCMTIME | S_NOQUOTA;
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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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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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* 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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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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mutex_unlock(&host_ui->ui_mutex);
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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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* 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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ubifs_assert(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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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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mutex_lock(&ui->ui_mutex);
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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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mutex_unlock(&ui->ui_mutex);
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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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* 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(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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* 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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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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out_free:
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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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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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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_unlock;
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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_unlock;
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}
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ui = ubifs_inode(inode);
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ubifs_assert(inode->i_size == ui->data_len);
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ubifs_assert(ubifs_inode(host)->xattr_size > ui->data_len);
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mutex_lock(&ui->ui_mutex);
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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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ubifs_err(c, "buffer size %zd, xattr len %d",
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size, ui->data_len);
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err = -ERANGE;
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goto out_iput;
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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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out_iput:
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mutex_unlock(&ui->ui_mutex);
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iput(inode);
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out_unlock:
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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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/* 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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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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dbg_gen("ino %lu ('%pd'), buffer size %zd", host->i_ino,
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dentry, size);
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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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return len;
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if (len > size)
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return -ERANGE;
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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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fname_name(&nm) = xent->name;
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fname_len(&nm) = le16_to_cpu(xent->nlen);
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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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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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if (err != -ENOENT) {
|
|
ubifs_err(c, "cannot find next direntry, error %d", err);
|
|
return err;
|
|
}
|
|
|
|
ubifs_assert(written <= size);
|
|
return written;
|
|
}
|
|
|
|
static int remove_xattr(struct ubifs_info *c, struct inode *host,
|
|
struct inode *inode, const struct fscrypt_name *nm)
|
|
{
|
|
int err;
|
|
struct ubifs_inode *host_ui = ubifs_inode(host);
|
|
struct ubifs_inode *ui = ubifs_inode(inode);
|
|
struct ubifs_budget_req req = { .dirtied_ino = 2, .mod_dent = 1,
|
|
.dirtied_ino_d = ALIGN(host_ui->data_len, 8) };
|
|
|
|
ubifs_assert(ui->data_len == inode->i_size);
|
|
|
|
err = ubifs_budget_space(c, &req);
|
|
if (err)
|
|
return err;
|
|
|
|
mutex_lock(&host_ui->ui_mutex);
|
|
host->i_ctime = current_time(host);
|
|
host_ui->xattr_cnt -= 1;
|
|
host_ui->xattr_size -= CALC_DENT_SIZE(fname_len(nm));
|
|
host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len);
|
|
host_ui->xattr_names -= fname_len(nm);
|
|
|
|
err = ubifs_jnl_delete_xattr(c, host, inode, nm);
|
|
if (err)
|
|
goto out_cancel;
|
|
mutex_unlock(&host_ui->ui_mutex);
|
|
|
|
ubifs_release_budget(c, &req);
|
|
return 0;
|
|
|
|
out_cancel:
|
|
host_ui->xattr_cnt += 1;
|
|
host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm));
|
|
host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
|
|
host_ui->xattr_names += fname_len(nm);
|
|
mutex_unlock(&host_ui->ui_mutex);
|
|
ubifs_release_budget(c, &req);
|
|
make_bad_inode(inode);
|
|
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(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;
|
|
|
|
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(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:
|
|
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 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
|
|
};
|