ubifs: move ubifs_xattr_handlers to .rodata

This makes it harder for accidental or malicious changes to
ubifs_xattr_handlers at runtime.

Cc: Richard Weinberger <richard@nod.at>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20230930050033.41174-26-wedsonaf@gmail.com
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ubifs: convert to ctime accessor functions

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Message-Id: <20230705190309.579783-76-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: port xattr to mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

ubifs: Fix AA deadlock when setting xattr for encrypted file

Following process:
vfs_setxattr(host)
ubifs_xattr_set
down_write(host_ui->xattr_sem) <- lock first time
create_xattr
ubifs_new_inode(host)
fscrypt_prepare_new_inode(host)
fscrypt_policy_to_inherit(host)
if (IS_ENCRYPTED(inode))
fscrypt_require_key(host)
fscrypt_get_encryption_info(host)
ubifs_xattr_get(host)
down_read(host_ui->xattr_sem) <- AA deadlock

, which may trigger an AA deadlock problem:

[ 102.620871] INFO: task setfattr:1599 blocked for more than 10 seconds.
[ 102.625298] Not tainted 5.19.0-rc7-00001-gb666b6823ce0-dirty #711
[ 102.628732] task:setfattr state:D stack: 0 pid: 1599
[ 102.628749] Call Trace:
[ 102.628753] <TASK>
[ 102.628776] __schedule+0x482/0x1060
[ 102.629964] schedule+0x92/0x1a0
[ 102.629976] rwsem_down_read_slowpath+0x287/0x8c0
[ 102.629996] down_read+0x84/0x170
[ 102.630585] ubifs_xattr_get+0xd1/0x370 [ubifs]
[ 102.630730] ubifs_crypt_get_context+0x1f/0x30 [ubifs]
[ 102.630791] fscrypt_get_encryption_info+0x7d/0x1c0
[ 102.630810] fscrypt_policy_to_inherit+0x56/0xc0
[ 102.630817] fscrypt_prepare_new_inode+0x35/0x160
[ 102.630830] ubifs_new_inode+0xcc/0x4b0 [ubifs]
[ 102.630873] ubifs_xattr_set+0x591/0x9f0 [ubifs]
[ 102.630961] xattr_set+0x8c/0x3e0 [ubifs]
[ 102.631003] __vfs_setxattr+0x71/0xc0
[ 102.631026] vfs_setxattr+0x105/0x270
[ 102.631034] do_setxattr+0x6d/0x110
[ 102.631041] setxattr+0xa0/0xd0
[ 102.631087] __x64_sys_setxattr+0x2f/0x40

Fetch a reproducer in [Link].

Just like ext4 does, which skips encrypting for inode with
EXT4_EA_INODE_FL flag. Stop encypting xattr inode for ubifs.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216260
Fixes: f4e3634a3b64222 ("ubifs: Fix races between xattr_{set|get} ...")
Fixes: d475a507457b5ca ("ubifs: Add skeleton for fscrypto")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Use NULL instead of using plain integer as pointer

This fixes the following sparse warnings:
fs/ubifs/xattr.c:680:58: warning: Using plain integer as NULL pointer

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Remove ui_mutex in ubifs_xattr_get and change_xattr

Since ubifs_xattr_get and ubifs_xattr_set cannot being executed
parallelly after importing @host_ui->xattr_sem, now we can remove
ui_mutex imported by commit ab92a20bce3b4c2 ("ubifs: make
ubifs_[get|set]xattr atomic").

@xattr_size, @xattr_names and @xattr_cnt can't be out of protection
by @host_ui->mutex yet, they are sill accesed in other places, such as
pack_inode() called by ubifs_write_inode() triggered by page-writeback.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Fix races between xattr_{set|get} and listxattr operations

UBIFS may occur some problems with concurrent xattr_{set|get} and
listxattr operations, such as assertion failure, memory corruption,
stale xattr value[1].

Fix it by importing a new rw-lock in @ubifs_inode to serilize write
operations on xattr, concurrent read operations are still effective,
just like ext4.

[1] https://lore.kernel.org/linux-mtd/20200630130438.141649-1-houtao1@huawei.com

Fixes: 1e51764a3c2ac05a23 ("UBIFS: add new flash file system")
Cc: stable@vger.kernel.org # v2.6+
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

acl: handle idmapped mounts

The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.

The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.

In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.

Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

ubifs: Fix off-by-one error

An inode is allowed to have ubifs_xattr_max_cnt() xattrs, so we must
complain only when an inode has more xattrs, having exactly
ubifs_xattr_max_cnt() xattrs is fine.
With this the maximum number of xattrs can be created without hitting
the "has too many xattrs" warning when removing it.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: xattr: Fix some potential memory leaks while iterating entries

Fix some potential memory leaks in error handling branches while
iterating xattr entries. For example, function ubifs_tnc_remove_ino()
forgets to free pxent if it exists. Similar problems also exist in
ubifs_purge_xattrs(), ubifs_add_orphan() and ubifs_jnl_write_inode().

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>
Fixes: 1e51764a3c2ac05a2 ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 336

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 51 franklin st fifth floor boston ma 02110
1301 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 246 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.674189849@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ubifs: Convert xattr inum to host order

UBIFS stores inode numbers as LE64 integers.
We have to convert them to host oder, otherwise
BE hosts won't be able to use the integer correctly.

Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 9ca2d7326444 ("ubifs: Limit number of xattrs per inode")
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Limit number of xattrs per inode

Since we have to write one deletion inode per xattr
into the journal, limit the max number of xattrs.

In theory UBIFS supported up to 65535 xattrs per inode.
But this never worked correctly, expect no powercuts happened.
Now we support only as many xattrs as we can store in 50% of a
LEB.
Even for tiny flashes this allows dozens of xattrs per inode,
which is for an embedded filesystem still fine.

In case someone has existing inodes with much more xattrs, it is
still possible to delete them.
UBIFS will fall back to an non-atomic deletion mode.

Reported-by: Stefan Agner <stefan@agner.ch>
Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>

Revert "ubifs: xattr: Don't operate on deleted inodes"

This reverts commit 11a6fc3dc743e22fb50f2196ec55bee5140d3c52.
UBIFS wants to assert that xattr operations are only issued on files
with positive link count. The said patch made this operations return
-ENOENT for unlinked files such that the asserts will no longer trigger.
This was wrong since xattr operations are perfectly fine on unlinked
files.
Instead the assertions need to be fixed/removed.

Cc: <stable@vger.kernel.org>
Fixes: 11a6fc3dc743 ("ubifs: xattr: Don't operate on deleted inodes")
Reported-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Pass struct ubifs_info to ubifs_assert()

This allows us to have more context in ubifs_assert()
and take different actions depending on the configuration.

Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: xattr: Don't operate on deleted inodes

xattr operations can race with unlink and the following assert triggers:
UBIFS assert failed in ubifs_jnl_change_xattr at 1606 (pid 6256)

Fix this by checking i_nlink before working on the host inode.

Cc: <stable@vger.kernel.org>
Fixes: 1e51764a3c2a ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs, xattr: remove misguided quota flags

Originally, Yang Dongsheng added quota support
for ubifs, but it turned out upstream won't accept it.

Since ubifs don't touch any quota code, S_NOQUOTA flag
is misguided here, and currently it is mainly used to
avoid recursion for system quota files.

Let's make things clearly and remove unnecessary and
misguied quota flags here.

Reported-by: Rock Lee <rockdotlee@gmail.com>
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: remove error message in ubifs_xattr_get

There is a situation that other modules, like overlayfs, try to get
xattr value with a small buffer, if they get -ERANGE, they will try
again with the proper buffer size. No need to report an error.

Signed-off-by: Rock Lee <rli@sierrawireless.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

fs, fscrypt: add an S_ENCRYPTED inode flag

Introduce a flag S_ENCRYPTED which can be set in ->i_flags to indicate
that the inode is encrypted using the fscrypt (fs/crypto/) mechanism.

Checking this flag will give the same information that
inode->i_sb->s_cop->is_encrypted(inode) currently does, but will be more
efficient. This will be useful for adding higher-level helper functions
for filesystems to use. For example we'll be able to replace this:

if (ext4_encrypted_inode(inode)) {
ret = fscrypt_get_encryption_info(inode);
if (ret)
return ret;
if (!fscrypt_has_encryption_key(inode))
return -ENOKEY;
}

with this:

ret = fscrypt_require_key(inode);
if (ret)
return ret;

... since we'll be able to retain the fast path for unencrypted files as
a single flag check, using an inline function. This wasn't possible
before because we'd have had to frequently call through the
->i_sb->s_cop->is_encrypted function pointer, even when the encryption
support was disabled or not being used.

Note: we don't define S_ENCRYPTED to 0 if CONFIG_FS_ENCRYPTION is
disabled because we want to continue to return an error if an encrypted
file is accessed without encryption support, rather than pretending that
it is unencrypted.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

ubifs: Massage assert in ubifs_xattr_set() wrt. init_xattrs

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>

ubifs: Correctly evict xattr inodes

UBIFS handles extended attributes just like files, as consequence of
that, they also have inodes.
Therefore UBIFS does all the inode machinery also for xattrs. Since new
inodes have i_nlink of 1, a file or xattr inode will be evicted
if i_nlink goes down to 0 after an unlink. UBIFS assumes this model also
for xattrs, which is not correct.
One can create a file "foo" with xattr "user.test". By reading
"user.test" an inode will be created, and by deleting "user.test" it
will get evicted later. The assumption breaks if the file "foo", which
hosts the xattrs, will be removed. VFS nor UBIFS does not remove each
xattr via ubifs_xattr_remove(), it just removes the host inode from
the TNC and all underlying xattr nodes too and the inode will remain
in the cache and wastes memory.

To solve this problem, remove xattr inodes from the VFS inode cache in
ubifs_xattr_remove() to make sure that they get evicted.

Fixes: 1e51764a3c2ac05a ("UBIFS: add new flash file system")
Cc: <stable@vger.kernel.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

fs: ubifs: replace CURRENT_TIME_SEC with current_time

CURRENT_TIME_SEC is not y2038 safe. current_time() will be transitioned
to use 64 bit time along with vfs in a separate patch. There is no plan
to transition CURRENT_TIME_SEC to use y2038 safe time interfaces.

current_time() returns timestamps according to the granularities set in
the inode's super_block. The granularity check to call
current_fs_time() or CURRENT_TIME_SEC is not required.

Use current_time() directly to update inode timestamp. Use
timespec_trunc during file system creation, before the first inode is
created.

Link: http://lkml.kernel.org/r/1491613030-11599-9-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Richard Weinberger <richard@nod.at>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ubifs: Add CONFIG_UBIFS_FS_SECURITY to disable/enable security labels

When write syscall is called, every time security label is searched to
determine that file's privileges should be changed.
If LSM(Linux Security Model) is not used, this is useless.

So introduce CONFIG_UBIFS_SECURITY to disable security labels. it's default
value is "y".

Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Implement encrypted filenames

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Massage assert in ubifs_xattr_set() wrt. fscrypto

When we're creating a new inode in UBIFS the inode is not
yet exposed and fscrypto calls ubifs_xattr_set() without
holding the inode mutex. This is okay but ubifs_xattr_set()
has to know about this.

Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Massage ubifs_listxattr() for encryption context

We have to make sure that we don't expose our internal
crypto context to userspace.

Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Add skeleton for fscrypto

This is the first building block to provide file level
encryption on UBIFS.

Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Export xattr get and set functions

For fscrypto we need this function outside of xattr.c.

Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Fix xattr_names length in exit paths

When the operation fails we also have to undo the changes
we made to ->xattr_names. Otherwise listxattr() will report
wrong lengths.

Cc: stable@vger.kernel.org
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: fix host xattr_len when changing xattr

When an extended attribute is changed, xattr_len of host inode is
recalculated. ui->data_len is updated before computation and result
is wrong. This patch adds a temporary variable to fix computation.

To reproduce the issue:

~# > a.txt
~# attr -s an-attr -V a-value a.txt
~# attr -s an-attr -V a-bit-bigger-value a.txt

Now host inode xattr_len is wrong. Forcing dbg_check_filesystem()
generates the following error:

[ 130.620140] UBIFS (ubi0:2): background thread "ubifs_bgt0_2" started, PID 565
[ 131.470790] UBIFS error (ubi0:2 pid 564): check_inodes: inode 646 has xattr size 240, but calculated size is 256
[ 131.481697] UBIFS (ubi0:2): dump of the inode 646 sitting in LEB 29:114688
[ 131.488953] magic 0x6101831
[ 131.492876] crc 0x9fce9091
[ 131.496836] node_type 0 (inode node)
[ 131.501193] group_type 1 (in node group)
[ 131.505788] sqnum 9278
[ 131.509191] len 160
[ 131.512549] key (646, inode)
[ 131.516688] creat_sqnum 9270
[ 131.520133] size 0
[ 131.523264] nlink 1
[ 131.526398] atime 1053025857.0
[ 131.530574] mtime 1053025857.0
[ 131.534714] ctime 1053025906.0
[ 131.538849] uid 0
[ 131.542009] gid 0
[ 131.545140] mode 33188
[ 131.548636] flags 0x1
[ 131.551977] xattr_cnt 1
[ 131.555108] xattr_size 240
[ 131.558420] xattr_names 12
[ 131.561670] compr_type 0x1
[ 131.564983] data len 0
[ 131.568125] UBIFS error (ubi0:2 pid 564): dbg_check_filesystem: file-system check failed with error -22
[ 131.578074] CPU: 0 PID: 564 Comm: mount Not tainted 4.4.12-g3639bea54a #24
[ 131.585352] Hardware name: Generic AM33XX (Flattened Device Tree)
[ 131.591918] [<c00151c0>] (unwind_backtrace) from [<c0012acc>] (show_stack+0x10/0x14)
[ 131.600177] [<c0012acc>] (show_stack) from [<c01c950c>] (dbg_check_filesystem+0x464/0x4d0)
[ 131.608934] [<c01c950c>] (dbg_check_filesystem) from [<c019f36c>] (ubifs_mount+0x14f8/0x2130)
[ 131.617991] [<c019f36c>] (ubifs_mount) from [<c00d7088>] (mount_fs+0x14/0x98)
[ 131.625572] [<c00d7088>] (mount_fs) from [<c00ed674>] (vfs_kern_mount+0x4c/0xd4)
[ 131.633435] [<c00ed674>] (vfs_kern_mount) from [<c00efb5c>] (do_mount+0x988/0xb50)
[ 131.641471] [<c00efb5c>] (do_mount) from [<c00f004c>] (SyS_mount+0x74/0xa0)
[ 131.648837] [<c00f004c>] (SyS_mount) from [<c000fe20>] (ret_fast_syscall+0x0/0x3c)
[ 131.665315] UBIFS (ubi0:2): background thread "ubifs_bgt0_2" stops

Signed-off-by: Pascal Eberhard <pascal.eberhard@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Fix xattr generic handler usage

UBIFS uses full names to work with xattrs, therefore we have to use
xattr_full_name() to obtain the xattr prefix as string.

Cc: <stable@vger.kernel.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Fixes: 2b88fc21ca ("ubifs: Switch to generic xattr handlers")
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Tested-by: Dongsheng Yang <dongsheng081251@gmail.com>

ubifs: Make xattr structures static

Fix sparse warnings from the use of "struct xattr_handler"
structures that are not exported by making them static. Fixes
the following sparse warnings:

/fs/ubifs/xattr.c:595:28: warning: symbol 'ubifs_user_xattr_handler' was not declared. Should it be static?
/fs/ubifs/xattr.c:601:28: warning: symbol 'ubifs_trusted_xattr_handler' was not declared. Should it be static?
/fs/ubifs/xattr.c:607:28: warning: symbol 'ubifs_security_xattr_handler' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

switch xattr_handler->set() to passing dentry and inode separately

preparation for similar switch in ->setxattr() (see the next commit for
rationale).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ubifs: Switch to generic xattr handlers

Ubifs internally uses special inodes for storing xattrs. Those inodes
had NULL {get,set,remove}xattr inode operations before this change, so
xattr operations on them would fail. The super block's s_xattr field
would also apply to those special inodes. However, the inodes are not
visible outside of ubifs, and so no xattr operations will ever be
carried out on them anyway.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

->getxattr(): pass dentry and inode as separate arguments

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ubifs: Remove unused header

UBIFS does not support POSIX ACLs, so there is no need for including any
POSIX ACL hesders.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

wrappers for ->i_mutex access

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ubifs: Use XATTR_*_PREFIX_LEN

...instead of open coding it.

Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Remove unused security xattr handler

Ubifs installs a security xattr handler in sb->s_xattr but doesn't use the
generic_{get,set,list,remove}xattr inode operations needed for processing
this list of attribute handlers; the handler is never called. Instead,
ubifs uses its own xattr handlers which also process security xattrs.

Remove the dead code.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: linux-mtd@lists.infradead.org
Cc: Subodh Nijsure <snijsure@grid-net.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ubifs: make ubifs_[get|set]xattr atomic

This commit make the ubifs_[get|set]xattr protected by ui_mutex.

Originally, there is a possibility that ubifs_getxattr to get
a wrong value.

P1 P2
---------- ----------
ubifs_getxattr ubifs_setxattr
- kfree()
- memcpy()
- kmemdup()

Then ubifs_getxattr() would get a non-sense data. To solve this
problem, this commit make the xattr of ubifs_inode updated in
atomic.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

UBIFS: Kill unneeded locking in ubifs_init_security

Fixes the following lockdep splat:
[ 1.244527] =============================================
[ 1.245193] [ INFO: possible recursive locking detected ]
[ 1.245193] 4.2.0-rc1+ #37 Not tainted
[ 1.245193] ---------------------------------------------
[ 1.245193] cp/742 is trying to acquire lock:
[ 1.245193] (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [<ffffffff812b3f69>] ubifs_init_security+0x29/0xb0
[ 1.245193]
[ 1.245193] but task is already holding lock:
[ 1.245193] (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [<ffffffff81198e7f>] path_openat+0x3af/0x1280
[ 1.245193]
[ 1.245193] other info that might help us debug this:
[ 1.245193] Possible unsafe locking scenario:
[ 1.245193]
[ 1.245193] CPU0
[ 1.245193] ----
[ 1.245193] lock(&sb->s_type->i_mutex_key#9);
[ 1.245193] lock(&sb->s_type->i_mutex_key#9);
[ 1.245193]
[ 1.245193] *** DEADLOCK ***
[ 1.245193]
[ 1.245193] May be due to missing lock nesting notation
[ 1.245193]
[ 1.245193] 2 locks held by cp/742:
[ 1.245193] #0: (sb_writers#5){.+.+.+}, at: [<ffffffff811ad37f>] mnt_want_write+0x1f/0x50
[ 1.245193] #1: (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [<ffffffff81198e7f>] path_openat+0x3af/0x1280
[ 1.245193]
[ 1.245193] stack backtrace:
[ 1.245193] CPU: 2 PID: 742 Comm: cp Not tainted 4.2.0-rc1+ #37
[ 1.245193] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140816_022509-build35 04/01/2014
[ 1.245193] ffffffff8252d530 ffff88007b023a38 ffffffff814f6f49 ffffffff810b56c5
[ 1.245193] ffff88007c30cc80 ffff88007b023af8 ffffffff810a150d ffff88007b023a68
[ 1.245193] 000000008101302a ffff880000000000 00000008f447e23f ffffffff8252d500
[ 1.245193] Call Trace:
[ 1.245193] [<ffffffff814f6f49>] dump_stack+0x4c/0x65
[ 1.245193] [<ffffffff810b56c5>] ? console_unlock+0x1c5/0x510
[ 1.245193] [<ffffffff810a150d>] __lock_acquire+0x1a6d/0x1ea0
[ 1.245193] [<ffffffff8109fa78>] ? __lock_is_held+0x58/0x80
[ 1.245193] [<ffffffff810a1a93>] lock_acquire+0xd3/0x270
[ 1.245193] [<ffffffff812b3f69>] ? ubifs_init_security+0x29/0xb0
[ 1.245193] [<ffffffff814fc83b>] mutex_lock_nested+0x6b/0x3a0
[ 1.245193] [<ffffffff812b3f69>] ? ubifs_init_security+0x29/0xb0
[ 1.245193] [<ffffffff812b3f69>] ? ubifs_init_security+0x29/0xb0
[ 1.245193] [<ffffffff812b3f69>] ubifs_init_security+0x29/0xb0
[ 1.245193] [<ffffffff8128e286>] ubifs_create+0xa6/0x1f0
[ 1.245193] [<ffffffff81198e7f>] ? path_openat+0x3af/0x1280
[ 1.245193] [<ffffffff81195d15>] vfs_create+0x95/0xc0
[ 1.245193] [<ffffffff8119929c>] path_openat+0x7cc/0x1280
[ 1.245193] [<ffffffff8109ffe3>] ? __lock_acquire+0x543/0x1ea0
[ 1.245193] [<ffffffff81088f20>] ? sched_clock_cpu+0x90/0xc0
[ 1.245193] [<ffffffff81088c00>] ? calc_global_load_tick+0x60/0x90
[ 1.245193] [<ffffffff81088f20>] ? sched_clock_cpu+0x90/0xc0
[ 1.245193] [<ffffffff811a9cef>] ? __alloc_fd+0xaf/0x180
[ 1.245193] [<ffffffff8119ac55>] do_filp_open+0x75/0xd0
[ 1.245193] [<ffffffff814ffd86>] ? _raw_spin_unlock+0x26/0x40
[ 1.245193] [<ffffffff811a9cef>] ? __alloc_fd+0xaf/0x180
[ 1.245193] [<ffffffff81189bd9>] do_sys_open+0x129/0x200
[ 1.245193] [<ffffffff81189cc9>] SyS_open+0x19/0x20
[ 1.245193] [<ffffffff81500717>] entry_SYSCALL_64_fastpath+0x12/0x6f

While the lockdep splat is a false positive, becuase path_openat holds i_mutex
of the parent directory and ubifs_init_security() tries to acquire i_mutex
of a new inode, it reveals that taking i_mutex in ubifs_init_security() is
in vain because it is only being called in the inode allocation path
and therefore nobody else can see the inode yet.

Cc: stable@vger.kernel.org # 3.20-
Reported-and-tested-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-and-tested-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: dedekind1@gmail.com

VFS: normal filesystems (and lustre): d_inode() annotations

that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

UBIFS: extend debug/message capabilities

In the case where we have more than one volumes on different UBI
devices, it may be not that easy to tell which volume prints the
messages. Add ubi number and volume id in ubifs_msg/warn/error
to help debug. These two values are passed by struct ubifs_info.

For those where ubifs_info is not initialized yet, ubifs_* is
replaced by pr_*. For those where ubifs_info is not avaliable,
ubifs_info is passed to the calling function as a const parameter.

The output looks like,

[ 95.444879] UBIFS (ubi0:1): background thread "ubifs_bgt0_1" started, PID 696
[ 95.484688] UBIFS (ubi0:1): UBIFS: mounted UBI device 0, volume 1, name "test1"
[ 95.484694] UBIFS (ubi0:1): LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[ 95.484699] UBIFS (ubi0:1): FS size: 30220288 bytes (28 MiB, 238 LEBs), journal size 1523712 bytes (1 MiB, 12 LEBs)
[ 95.484703] UBIFS (ubi0:1): reserved for root: 1427378 bytes (1393 KiB)
[ 95.484709] UBIFS (ubi0:1): media format: w4/r0 (latest is w4/r0), UUID 40DFFC0E-70BE-4193-8905-F7D6DFE60B17, small LPT model
[ 95.489875] UBIFS (ubi1:0): background thread "ubifs_bgt1_0" started, PID 699
[ 95.529713] UBIFS (ubi1:0): UBIFS: mounted UBI device 1, volume 0, name "test2"
[ 95.529718] UBIFS (ubi1:0): LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[ 95.529724] UBIFS (ubi1:0): FS size: 19808256 bytes (18 MiB, 156 LEBs), journal size 1015809 bytes (0 MiB, 8 LEBs)
[ 95.529727] UBIFS (ubi1:0): reserved for root: 935592 bytes (913 KiB)
[ 95.529733] UBIFS (ubi1:0): media format: w4/r0 (latest is w4/r0), UUID EEB7779D-F419-4CA9-811B-831CAC7233D4, small LPT model

[ 954.264767] UBIFS error (ubi1:0 pid 756): ubifs_read_node: bad node type (255 but expected 6)
[ 954.367030] UBIFS error (ubi1:0 pid 756): ubifs_read_node: bad node at LEB 0:0, LEB mapping status 1

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: add ubifs_err() to print error reason

This patch adds ubifs_err() output to some error paths to tell the user
what's going on.

Artem: improve the messages, rename too long variable

Signed-off-by: Subodh Nijsure <snijsure@grid-net.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Acked-by: Brad Mouring <brad.mouring@ni.com>
Acked-by: Terry Wilcox <terry.wilcox@ni.com>
Acked-by: Gratian Crisan <gratian.crisan@ni.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: Add security.* XATTR support for the UBIFS

Artem: rename static functions so that they do not use the "ubifs_" prefix - we
only use this prefix for non-static functions.
Artem: remove few junk white-space changes in file.c

Signed-off-by: Subodh Nijsure <snijsure@grid-net.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Acked-by: Brad Mouring <brad.mouring@ni.com>
Acked-by: Terry Wilcox <terry.wilcox@ni.com>
Acked-by: Gratian Crisan <gratian.crisan@ni.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: Add xattr support for symlinks

Artem: rename the __ubifs_setxattr() functions to just 'setxattr()'.

Signed-off-by: Subodh Nijsure <snijsure@grid-net.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Acked-by: Terry Wilcox <terry.wilcox@ni.com>
Acked-by: Gratian Crisan <gratian.crisan@ni.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

ubifs: switch to %pd

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

UBIFS: get rid of dbg_err

This patch removes the 'dbg_err()' macro and we now use 'ubifs_err()' instead.
The idea of 'dbg_err()' was to compile out some error message to make the
binary a bit smaller - but I think it was a bad idea.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

vfs: make it possible to access the dentry hash/len as one 64-bit entry

This allows comparing hash and len in one operation on 64-bit
architectures. Right now only __d_lookup_rcu() takes advantage of this,
since that is the case we care most about.

The use of anonymous struct/unions hides the alternate 64-bit approach
from most users, the exception being a few cases where we initialize a
'struct qstr' with a static initializer. This makes the problematic
cases use a new QSTR_INIT() helper function for that (but initializing
just the name pointer with a "{ .name = xyzzy }" initializer remains
valid, as does just copying another qstr structure).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

UBIFS: Use kmemdup rather than duplicating its implementation

The semantic patch that makes this change is available
in scripts/coccinelle/api/memdup.cocci.

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

filesystems: add set_nlink()

Replace remaining direct i_nlink updates with a new set_nlink()
updater function.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

filesystems: add missing nlink wrappers

Replace direct i_nlink updates with the respective updater function
(inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

UBIFS: make xattr operations names consistent

This is just a tiny clean-up patch. The variable name for empty address
space operations is "empty_aops". Let's use consistent names for empty
inode and file operations: "empty_iops" and "empty_fops", instead of
inconsistent "none_inode_operations" and "none_file_operations".

Artem: re-write the commit message.

Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

fs: export empty_aops

With the ->sync_page() hook gone, we have a few users that
add their own static address_space_operations without any
functions defined.

fs/inode.c already has an empty_aops that it uses for init
purposes. Lets export that and use it in the places where
an otherwise empty aops was defined.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

const: mark remaining address_space_operations const

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

UBIFS: constify file and inode operations

This patch adds 'const' qualifier to UBIFS xattr inode and file
operations.

Pointed-out-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

helpers for acl caching + switch to those

helpers: get_cached_acl(inode, type), set_cached_acl(inode, type, acl),
forget_cached_acl(inode, type).

ubifs/xattr.c needed includes reordered, the rest is a plain switchover.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

UBIFS: remove unneeded unlikely()

IS_ERR() macro already has unlikely(), so do not use constructions
like 'if (unlikely(IS_ERR())'.

Signed-off-by: Hirofumi Nakagawa <hnakagawa@miraclelinux.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

UBIFS: xattr bugfixes

Xattr code has not been tested for a while and there were
serveral bugs. One of them is using wrong inode in
'ubifs_jnl_change_xattr()'. The other is a deadlock in
'ubifs_setxattr()': the i_mutex is locked in
'cap_inode_need_killpriv()' path, so deadlock happens when
'ubifs_setxattr()' tries to lock it again.

Thanks to Zoltan Sogor for finding these bugs.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

UBIFS: fix budgeting request alignment in xattr code

Data length has to be aligned in the budgeting request. Code
in xattr.c did not do this.

Signed-off-by: Zoltan Sogor <weth@inf.u-szeged.hu>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

UBIFS: align inode data to eight

UBIFS aligns node lengths to 8, so budgeting has to do the
same. Well, direntry, inode, and page budgets are already
aligned, but not inode data budget (e.g., data in special
devices or symlinks). Do this for inode data as well.
Also, add corresponding debugging checks.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

UBIFS: add new flash file system

This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.html

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>