If the number of dirty pages to be written back is large,
then writeback_inodes_sb will block waiting for a long time,
causing hung task detection alarm. Therefore, we should limit
the maximum number of pages written back this time, which let
the budget be completed faster. The remaining dirty pages
tend to rely on the writeback mechanism to complete the
synchronization.
Fixes: b6e51316da ("writeback: separate starting of sync vs opportunistic writeback")
Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Signed-off-by: Richard Weinberger <richard@nod.at>
Currently on a freshly mounted UBIFS, c->min_log_bytes is 0.
This can lead to a log overrun and make commits fail.
Recent kernels will report the following assert:
UBIFS assert failed: c->lhead_lnum != c->ltail_lnum, in fs/ubifs/log.c:412
c->min_log_bytes can have two states, 0 and c->leb_size.
It controls how much bytes of the log area are reserved for non-bud
nodes such as commit nodes.
After a commit it has to be set to c->leb_size such that we have always
enough space for a commit. While a commit runs it can be 0 to make the
remaining bytes of the log available to writers.
Having it set to 0 right after mount is wrong since no space for commits
is reserved.
Fixes: 1e51764a3c ("UBIFS: add new flash file system")
Reported-and-tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
We unlock after orphan_delete(), so no need to unlock
in the function too.
Reported-by: Han Xu <han.xu@nxp.com>
Fixes: 8009ce956c ("ubifs: Don't leak orphans on memory during commit")
Signed-off-by: Richard Weinberger <richard@nod.at>
migrate_page_move_mapping() doesn't use the mode argument. Remove it
and update callers accordingly.
Link: http://lkml.kernel.org/r/20190508210301.8472-1-keith.busch@intel.com
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Support for zstd compression
- Support for offline signed filesystems
- Various fixes for regressions
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Merge tag 'upstream-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs
Pull UBIFS updates from Richard Weinberger:
- Support for zstd compression
- Support for offline signed filesystems
- Various fixes for regressions
* tag 'upstream-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
ubifs: Don't leak orphans on memory during commit
ubifs: Check link count of inodes when killing orphans.
ubifs: Add support for zstd compression.
ubifs: support offline signed images
ubifs: remove unnecessary check in ubifs_log_start_commit
ubifs: Fix typo of output in get_cs_sqnum
ubifs: Simplify redundant code
ubifs: Correctly use tnc_next() in search_dh_cookie()
- Standardize parameter checking for the SETFLAGS and FSSETXATTR ioctls
(which were the file attribute setters for ext4 and xfs and have now
been hoisted to the vfs)
- Only allow the DAX flag to be set on files and directories.
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Merge tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull common SETFLAGS/FSSETXATTR parameter checking from Darrick Wong:
"Here's a patch series that sets up common parameter checking functions
for the FS_IOC_SETFLAGS and FS_IOC_FSSETXATTR ioctl implementations.
The goal here is to reduce the amount of behaviorial variance between
the filesystems where those ioctls originated (ext2 and XFS,
respectively) and everybody else.
- Standardize parameter checking for the SETFLAGS and FSSETXATTR
ioctls (which were the file attribute setters for ext4 and xfs and
have now been hoisted to the vfs)
- Only allow the DAX flag to be set on files and directories"
* tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
vfs: only allow FSSETXATTR to set DAX flag on files and dirs
vfs: teach vfs_ioc_fssetxattr_check to check extent size hints
vfs: teach vfs_ioc_fssetxattr_check to check project id info
vfs: create a generic checking function for FS_IOC_FSSETXATTR
vfs: create a generic checking and prep function for FS_IOC_SETFLAGS
Here is the "big" driver core and debugfs changes for 5.3-rc1
It's a lot of different patches, all across the tree due to some api
changes and lots of debugfs cleanups. Because of this, there is going
to be some merge issues with your tree at the moment, I'll follow up
with the expected resolutions to make it easier for you.
Other than the debugfs cleanups, in this set of changes we have:
- bus iteration function cleanups (will cause build warnings
with s390 and coresight drivers in your tree)
- scripts/get_abi.pl tool to display and parse Documentation/ABI
entries in a simple way
- cleanups to Documenatation/ABI/ entries to make them parse
easier due to typos and other minor things
- default_attrs use for some ktype users
- driver model documentation file conversions to .rst
- compressed firmware file loading
- deferred probe fixes
All of these have been in linux-next for a while, with a bunch of merge
issues that Stephen has been patient with me for. Other than the merge
issues, functionality is working properly in linux-next :)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and debugfs updates from Greg KH:
"Here is the "big" driver core and debugfs changes for 5.3-rc1
It's a lot of different patches, all across the tree due to some api
changes and lots of debugfs cleanups.
Other than the debugfs cleanups, in this set of changes we have:
- bus iteration function cleanups
- scripts/get_abi.pl tool to display and parse Documentation/ABI
entries in a simple way
- cleanups to Documenatation/ABI/ entries to make them parse easier
due to typos and other minor things
- default_attrs use for some ktype users
- driver model documentation file conversions to .rst
- compressed firmware file loading
- deferred probe fixes
All of these have been in linux-next for a while, with a bunch of
merge issues that Stephen has been patient with me for"
* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
debugfs: make error message a bit more verbose
orangefs: fix build warning from debugfs cleanup patch
ubifs: fix build warning after debugfs cleanup patch
driver: core: Allow subsystems to continue deferring probe
drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
arch_topology: Remove error messages on out-of-memory conditions
lib: notifier-error-inject: no need to check return value of debugfs_create functions
swiotlb: no need to check return value of debugfs_create functions
ceph: no need to check return value of debugfs_create functions
sunrpc: no need to check return value of debugfs_create functions
ubifs: no need to check return value of debugfs_create functions
orangefs: no need to check return value of debugfs_create functions
nfsd: no need to check return value of debugfs_create functions
lib: 842: no need to check return value of debugfs_create functions
debugfs: provide pr_fmt() macro
debugfs: log errors when something goes wrong
drivers: s390/cio: Fix compilation warning about const qualifiers
drivers: Add generic helper to match by of_node
driver_find_device: Unify the match function with class_find_device()
bus_find_device: Unify the match callback with class_find_device
...
- Preparations for supporting encryption on ext4 filesystems where the
filesystem block size is smaller than PAGE_SIZE.
- Don't allow setting encryption policies on dead directories.
- Various cleanups.
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Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt
Pull fscrypt updates from Eric Biggers:
- Preparations for supporting encryption on ext4 filesystems where the
filesystem block size is smaller than PAGE_SIZE.
- Don't allow setting encryption policies on dead directories.
- Various cleanups.
* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
fscrypt: document testing with xfstests
fscrypt: remove selection of CONFIG_CRYPTO_SHA256
fscrypt: remove unnecessary includes of ratelimit.h
fscrypt: don't set policy for a dead directory
ext4: encrypt only up to last block in ext4_bio_write_page()
ext4: decrypt only the needed block in __ext4_block_zero_page_range()
ext4: decrypt only the needed blocks in ext4_block_write_begin()
ext4: clear BH_Uptodate flag on decryption error
fscrypt: decrypt only the needed blocks in __fscrypt_decrypt_bio()
fscrypt: support decrypting multiple filesystem blocks per page
fscrypt: introduce fscrypt_decrypt_block_inplace()
fscrypt: handle blocksize < PAGE_SIZE in fscrypt_zeroout_range()
fscrypt: support encrypting multiple filesystem blocks per page
fscrypt: introduce fscrypt_encrypt_block_inplace()
fscrypt: clean up some BUG_ON()s in block encryption/decryption
fscrypt: rename fscrypt_do_page_crypto() to fscrypt_crypt_block()
fscrypt: remove the "write" part of struct fscrypt_ctx
fscrypt: simplify bounce page handling
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Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull keyring ACL support from David Howells:
"This changes the permissions model used by keys and keyrings to be
based on an internal ACL by the following means:
- Replace the permissions mask internally with an ACL that contains a
list of ACEs, each with a specific subject with a permissions mask.
Potted default ACLs are available for new keys and keyrings.
ACE subjects can be macroised to indicate the UID and GID specified
on the key (which remain). Future commits will be able to add
additional subject types, such as specific UIDs or domain
tags/namespaces.
Also split a number of permissions to give finer control. Examples
include splitting the revocation permit from the change-attributes
permit, thereby allowing someone to be granted permission to revoke
a key without allowing them to change the owner; also the ability
to join a keyring is split from the ability to link to it, thereby
stopping a process accessing a keyring by joining it and thus
acquiring use of possessor permits.
- Provide a keyctl to allow the granting or denial of one or more
permits to a specific subject. Direct access to the ACL is not
granted, and the ACL cannot be viewed"
* tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
keys: Provide KEYCTL_GRANT_PERMISSION
keys: Replace uid/gid/perm permissions checking with an ACL
If an orphan has child orphans (xattrs), and due
to a commit the parent orpahn cannot get free()'ed immediately,
put also all child orphans on the erase list.
Otherwise UBIFS will free() them only upon unmount and we
waste memory.
Fixes: 988bec4131 ("ubifs: orphan: Handle xattrs like files")
Signed-off-by: Richard Weinberger <richard@nod.at>
O_TMPFILE files can change their link count back to non-zero.
This corner case needs to get addressed in the orphans subsystem
too.
Fixes: 474b93704f ("ubifs: Implement O_TMPFILE")
Reported-by: Lars Persson <lists@bofh.nu>
Signed-off-by: Richard Weinberger <richard@nod.at>
zstd shows a good compression rate and is faster than lzo,
also on slow ARM cores.
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Michele Dionisio <michele.dionisio@gmail.com>
[rw: rewrote commit message]
Signed-off-by: Richard Weinberger <richard@nod.at>
HMACs can only be generated on the system the UBIFS image is running on.
To support offline signed images we add a PKCS#7 signature to the UBIFS
image which can be created by mkfs.ubifs.
Both the master node and the superblock need to be authenticated, during
normal runtime both are protected with HMACs. For offline signature
support however only a single signature is desired. We add a signature
covering the superblock node directly behind it. To protect the master
node a hash of the master node is added to the superblock which is used
when the master node doesn't contain a HMAC.
Transition to a read/write filesystem is also supported. During
transition first the master node is rewritten with a HMAC (implicitly,
it is written anyway as the FS is marked dirty). Afterwards the
superblock is rewritten with a HMAC. Once after the image has been
mounted read/write it is HMAC only, the signature is no longer required
or even present on the filesystem.
In an offline signed image the master node is authenticated by the
superblock. In a transition to r/w we have to make sure that the master
node is rewritten before the superblock node. In this case the master
node gets a HMAC and its authenticity no longer depends on the
superblock node. There are some cases in which the current code first
writes the superblock node though, so with this patch writing of the
superblock node is delayed until the master node is written.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
In ubifs_log_start_commit, the value of c->lhead_offs is zero or set
to zero by code bellow.
/* Switch to the next log LEB */
if (c->lhead_offs) {
c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
ubifs_assert(c->lhead_lnum != c->ltail_lnum);
c->lhead_offs = 0;
}
The value of 'len' can not exceed 'max_len' which assigned value by
code bellow.
max_len = UBIFS_CS_NODE_SZ + c->jhead_cnt * UBIFS_REF_NODE_SZ;
The value of c->lhead_offs changed by code bellow and cannot exceed
'max_len'.
c->lhead_offs += len;
if (c->lhead_offs == c->leb_size) {
c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
c->lhead_offs = 0;
}
Usually, the size of PEB is between 64KB and 256KB. So the value of
c->lhead_offs is far less than c->leb_size. The check
'if (c->lhead_offs == c->leb_size)' could never to be true.
Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Richard Weinberger <richard@nod.at>
"Not a CS node" makes more sense than "Node a CS node".
Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Richard Weinberger <richard@nod.at>
cbuf's size can be simply assigned.
Signed-off-by: Liu Song <liu.song11@zte.com.cn>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Richard Weinberger <richard@nod.at>
Commit c877154d30 fixed an uninitialized variable and optimized
the function to not call tnc_next() in the first iteration of the
loop. While this seemed perfectly legit and wise, it turned out to
be illegal.
If the lookup function does not find an exact match it will rewind
the cursor by 1.
The rewinded cursor will not match the name hash we are looking for
and this results in a spurious -ENOENT.
So we need to move to the next entry in case of an non-exact match,
but not if the match was exact.
While we are here, update the documentation to avoid further confusion.
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: c877154d30 ("ubifs: Fix uninitialized variable in search_dh_cookie()")
Fixes: 781f675e2d ("ubifs: Fix unlink code wrt. double hash lookups")
Signed-off-by: Richard Weinberger <richard@nod.at>
Stephen writes:
After merging the driver-core tree, today's linux-next build (arm
multi_v7_defconfig) produced this warning:
fs/ubifs/debug.c: In function 'dbg_debugfs_init_fs':
fs/ubifs/debug.c:2812:6: warning: unused variable 'err' [-Wunused-variable]
int err, n;
^~~
So fix this up properly.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Richard Weinberger <richard@nod.at>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Cc: Richard Weinberger <richard@nod.at>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190612152120.GA17450@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Create a generic function to check incoming FS_IOC_SETFLAGS flag values
and later prepare the inode for updates so that we can standardize the
implementations that follow ext4's flag values.
Note that the efivarfs implementation no longer fails a no-op SETFLAGS
without CAP_LINUX_IMMUTABLE since that's the behavior in ext*.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Replace the uid/gid/perm permissions checking on a key with an ACL to allow
the SETATTR and SEARCH permissions to be split. This will also allow a
greater range of subjects to represented.
============
WHY DO THIS?
============
The problem is that SETATTR and SEARCH cover a slew of actions, not all of
which should be grouped together.
For SETATTR, this includes actions that are about controlling access to a
key:
(1) Changing a key's ownership.
(2) Changing a key's security information.
(3) Setting a keyring's restriction.
And actions that are about managing a key's lifetime:
(4) Setting an expiry time.
(5) Revoking a key.
and (proposed) managing a key as part of a cache:
(6) Invalidating a key.
Managing a key's lifetime doesn't really have anything to do with
controlling access to that key.
Expiry time is awkward since it's more about the lifetime of the content
and so, in some ways goes better with WRITE permission. It can, however,
be set unconditionally by a process with an appropriate authorisation token
for instantiating a key, and can also be set by the key type driver when a
key is instantiated, so lumping it with the access-controlling actions is
probably okay.
As for SEARCH permission, that currently covers:
(1) Finding keys in a keyring tree during a search.
(2) Permitting keyrings to be joined.
(3) Invalidation.
But these don't really belong together either, since these actions really
need to be controlled separately.
Finally, there are number of special cases to do with granting the
administrator special rights to invalidate or clear keys that I would like
to handle with the ACL rather than key flags and special checks.
===============
WHAT IS CHANGED
===============
The SETATTR permission is split to create two new permissions:
(1) SET_SECURITY - which allows the key's owner, group and ACL to be
changed and a restriction to be placed on a keyring.
(2) REVOKE - which allows a key to be revoked.
The SEARCH permission is split to create:
(1) SEARCH - which allows a keyring to be search and a key to be found.
(2) JOIN - which allows a keyring to be joined as a session keyring.
(3) INVAL - which allows a key to be invalidated.
The WRITE permission is also split to create:
(1) WRITE - which allows a key's content to be altered and links to be
added, removed and replaced in a keyring.
(2) CLEAR - which allows a keyring to be cleared completely. This is
split out to make it possible to give just this to an administrator.
(3) REVOKE - see above.
Keys acquire ACLs which consist of a series of ACEs, and all that apply are
unioned together. An ACE specifies a subject, such as:
(*) Possessor - permitted to anyone who 'possesses' a key
(*) Owner - permitted to the key owner
(*) Group - permitted to the key group
(*) Everyone - permitted to everyone
Note that 'Other' has been replaced with 'Everyone' on the assumption that
you wouldn't grant a permit to 'Other' that you wouldn't also grant to
everyone else.
Further subjects may be made available by later patches.
The ACE also specifies a permissions mask. The set of permissions is now:
VIEW Can view the key metadata
READ Can read the key content
WRITE Can update/modify the key content
SEARCH Can find the key by searching/requesting
LINK Can make a link to the key
SET_SECURITY Can change owner, ACL, expiry
INVAL Can invalidate
REVOKE Can revoke
JOIN Can join this keyring
CLEAR Can clear this keyring
The KEYCTL_SETPERM function is then deprecated.
The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set,
or if the caller has a valid instantiation auth token.
The KEYCTL_INVALIDATE function then requires INVAL.
The KEYCTL_REVOKE function then requires REVOKE.
The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an
existing keyring.
The JOIN permission is enabled by default for session keyrings and manually
created keyrings only.
======================
BACKWARD COMPATIBILITY
======================
To maintain backward compatibility, KEYCTL_SETPERM will translate the
permissions mask it is given into a new ACL for a key - unless
KEYCTL_SET_ACL has been called on that key, in which case an error will be
returned.
It will convert possessor, owner, group and other permissions into separate
ACEs, if each portion of the mask is non-zero.
SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE
permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned
on if a keyring is being altered.
The KEYCTL_DESCRIBE function translates the ACL back into a permissions
mask to return depending on possessor, owner, group and everyone ACEs.
It will make the following mappings:
(1) INVAL, JOIN -> SEARCH
(2) SET_SECURITY -> SETATTR
(3) REVOKE -> WRITE if SETATTR isn't already set
(4) CLEAR -> WRITE
Note that the value subsequently returned by KEYCTL_DESCRIBE may not match
the value set with KEYCTL_SETATTR.
=======
TESTING
=======
This passes the keyutils testsuite for all but a couple of tests:
(1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now
returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed
if the type doesn't have ->read(). You still can't actually read the
key.
(2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't
work as Other has been replaced with Everyone in the ACL.
Signed-off-by: David Howells <dhowells@redhat.com>
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>
Currently fscrypt_decrypt_page() does one of two logically distinct
things depending on whether FS_CFLG_OWN_PAGES is set in the filesystem's
fscrypt_operations: decrypt a pagecache page in-place, or decrypt a
filesystem block in-place in any page. Currently these happen to share
the same implementation, but this conflates the notion of blocks and
pages. It also makes it so that all callers have to provide inode and
lblk_num, when fscrypt could determine these itself for pagecache pages.
Therefore, move the FS_CFLG_OWN_PAGES behavior into a new function
fscrypt_decrypt_block_inplace(). This mirrors
fscrypt_encrypt_block_inplace().
This is in preparation for allowing encryption on ext4 filesystems with
blocksize != PAGE_SIZE.
Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
fscrypt_encrypt_page() behaves very differently depending on whether the
filesystem set FS_CFLG_OWN_PAGES in its fscrypt_operations. This makes
the function difficult to understand and document. It also makes it so
that all callers have to provide inode and lblk_num, when fscrypt could
determine these itself for pagecache pages.
Therefore, move the FS_CFLG_OWN_PAGES behavior into a new function
fscrypt_encrypt_block_inplace().
This is in preparation for allowing encryption on ext4 filesystems with
blocksize != PAGE_SIZE.
Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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: 9ca2d73264 ("ubifs: Limit number of xattrs per inode")
Signed-off-by: Richard Weinberger <richard@nod.at>
CONFIG_UBIFS_FS_ENCRYPTION is gone, fscrypt is now
controlled via CONFIG_FS_ENCRYPTION.
This problem slipped into the tree because of a mis-merge on
my side.
Reported-by: Eric Biggers <ebiggers@kernel.org>
Fixes: eea2c05d92 ("ubifs: Remove #ifdef around CONFIG_FS_ENCRYPTION")
Signed-off-by: Richard Weinberger <richard@nod.at>
Fix gcc build error while CONFIG_UBIFS_FS_XATTR
is not set
fs/ubifs/dir.o: In function `ubifs_unlink':
dir.c:(.text+0x260): undefined reference to `ubifs_purge_xattrs'
fs/ubifs/dir.o: In function `do_rename':
dir.c:(.text+0x1edc): undefined reference to `ubifs_purge_xattrs'
fs/ubifs/dir.o: In function `ubifs_rmdir':
dir.c:(.text+0x2638): undefined reference to `ubifs_purge_xattrs'
Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 9ca2d73264 ("ubifs: Limit number of xattrs per inode")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
- fscrypt framework usage updates
- One huge fix for xattr unlink
- Cleanup of fscrypt ifdefs
- Fix for our new UBIFS auth feature
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Merge tag 'upstream-5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/rw/ubifs
Pull UBI/UBIFS updates from Richard Weinberger:
- fscrypt framework usage updates
- One huge fix for xattr unlink
- Cleanup of fscrypt ifdefs
- Fix for our new UBIFS auth feature
* tag 'upstream-5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
ubi: wl: Fix uninitialized variable
ubifs: Drop unnecessary setting of zbr->znode
ubifs: Remove ifdefs around CONFIG_UBIFS_ATIME_SUPPORT
ubifs: Remove #ifdef around CONFIG_FS_ENCRYPTION
ubifs: Limit number of xattrs per inode
ubifs: orphan: Handle xattrs like files
ubifs: journal: Handle xattrs like files
ubifs: find.c: replace swap function with built-in one
ubifs: Do not skip hash checking in data nodes
ubifs: work around high stack usage with clang
ubifs: remove unused function __ubifs_shash_final
ubifs: remove unnecessary #ifdef around fscrypt_ioctl_get_policy()
ubifs: remove unnecessary calls to set up directory key
miscellaneous cleanups.
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Merge tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt
Pull fscrypt updates from Ted Ts'o:
"Clean up fscrypt's dcache revalidation support, and other
miscellaneous cleanups"
* tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
fscrypt: cache decrypted symlink target in ->i_link
vfs: use READ_ONCE() to access ->i_link
fscrypt: fix race where ->lookup() marks plaintext dentry as ciphertext
fscrypt: only set dentry_operations on ciphertext dentries
fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory
fscrypt: fix race allowing rename() and link() of ciphertext dentries
fscrypt: clean up and improve dentry revalidation
fscrypt: use READ_ONCE() to access ->i_crypt_info
fscrypt: remove WARN_ON_ONCE() when decryption fails
fscrypt: drop inode argument from fscrypt_get_ctx()
in dbg_walk_index ubifs_load_znode is used to load the znode behind
a zbranch. ubifs_load_znode links the new child znode to the zbranch,
so doing it again is unnecessary.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
ifdefs reduce readability and compile coverage. This removes the ifdefs
around CONFIG_UBIFS_ATIME_SUPPORT by replacing them with IS_ENABLED()
where applicable. The fs layer would fall back to generic_update_time()
when .update_time doesn't exist. We do this fallback explicitly now.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
ifdefs reduce readablity and compile coverage. This removes the ifdefs
around CONFIG_FS_ENCRYPTION by using IS_ENABLED and relying on static
inline wrappers. A new static inline wrapper for setting sb->s_cop is
introduced to allow filesystems to unconditionally compile in their
s_cop operations.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
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: 1e51764a3c ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>
Like for the journal case, make sure that we track all xattr
inodes.
Otherwise UBIFS might not be able to locate stale xattr inodes
upon recovery.
Reported-by: Stefan Agner <stefan@agner.ch>
Fixes: 1e51764a3c ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>
If an inode hosts xattrs, create deletion entries for each
inode. That way we can make sure that upon journal replay UBIFS
can find find all xattr inodes.
Otherwise it can happen that GC consumed already a LEB which contained
parts of the TNC that pointed to the xattrs and we no longer
find all xattr inodes, which will confuse the LPT and cause
space allocation issues.
Reported-by: Stefan Agner <stefan@agner.ch>
Fixes: 1e51764a3c ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>
Replace swap_dirty_idx function with built-in one,
because swap_dirty_idx does only a simple byte to byte swap.
Since Spectre mitigations have made indirect function calls more
expensive, and the default simple byte copies swap is implemented
without them, an "optimized" custom swap function is now
a waste of time as well as code.
Signed-off-by: Andrey Abramov <st5pub@yandex.ru>
Reviewed by: George Spelvin <lkml@sdf.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
UBIFS bails out early from try_read_node() when it doesn't have to check
the CRC. Still the node hash has to be checked, otherwise wrong data
could be sneaked into the FS. Fix this by not bailing out early and
always checking the node hash.
Fixes: 16a26b20d2 ("ubifs: authentication: Add hashes to index nodes")
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
Building this file with clang can result in large stack usage as seen from
this warning:
fs/ubifs/auth.c:78:5: error: stack frame size of 1152 bytes in function 'ubifs_prepare_auth_node'
The problem is that inlining ubifs_hash_calc_hmac() leads to
two SHASH_DESC_ON_STACK() blocks in the same function, and clang
for some reason does not reuse the stack space as it should.
Putting the first declaration into a separate basic block avoids
this problem and reduces the stack allocation to 640 bytes.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
There is no callers in tree, and can be removed.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
When !CONFIG_FS_ENCRYPTION, fscrypt_ioctl_get_policy() is already
stubbed out to return -EOPNOTSUPP, so the extra #ifdef is not needed.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
In ubifs_unlink() and ubifs_rmdir(), remove the call to
fscrypt_get_encryption_info() that precedes fscrypt_setup_filename().
This call was unnecessary, because fscrypt_setup_filename() already
tries to set up the directory's encryption key.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Pull vfs inode freeing updates from Al Viro:
"Introduction of separate method for RCU-delayed part of
->destroy_inode() (if any).
Pretty much as posted, except that destroy_inode() stashes
->free_inode into the victim (anon-unioned with ->i_fops) before
scheduling i_callback() and the last two patches (sockfs conversion
and folding struct socket_wq into struct socket) are excluded - that
pair should go through netdev once davem reopens his tree"
* 'work.icache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (58 commits)
orangefs: make use of ->free_inode()
shmem: make use of ->free_inode()
hugetlb: make use of ->free_inode()
overlayfs: make use of ->free_inode()
jfs: switch to ->free_inode()
fuse: switch to ->free_inode()
ext4: make use of ->free_inode()
ecryptfs: make use of ->free_inode()
ceph: use ->free_inode()
btrfs: use ->free_inode()
afs: switch to use of ->free_inode()
dax: make use of ->free_inode()
ntfs: switch to ->free_inode()
securityfs: switch to ->free_inode()
apparmor: switch to ->free_inode()
rpcpipe: switch to ->free_inode()
bpf: switch to ->free_inode()
mqueue: switch to ->free_inode()
ufs: switch to ->free_inode()
coda: switch to ->free_inode()
...
Pull crypto update from Herbert Xu:
"API:
- Add support for AEAD in simd
- Add fuzz testing to testmgr
- Add panic_on_fail module parameter to testmgr
- Use per-CPU struct instead multiple variables in scompress
- Change verify API for akcipher
Algorithms:
- Convert x86 AEAD algorithms over to simd
- Forbid 2-key 3DES in FIPS mode
- Add EC-RDSA (GOST 34.10) algorithm
Drivers:
- Set output IV with ctr-aes in crypto4xx
- Set output IV in rockchip
- Fix potential length overflow with hashing in sun4i-ss
- Fix computation error with ctr in vmx
- Add SM4 protected keys support in ccree
- Remove long-broken mxc-scc driver
- Add rfc4106(gcm(aes)) cipher support in cavium/nitrox"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (179 commits)
crypto: ccree - use a proper le32 type for le32 val
crypto: ccree - remove set but not used variable 'du_size'
crypto: ccree - Make cc_sec_disable static
crypto: ccree - fix spelling mistake "protedcted" -> "protected"
crypto: caam/qi2 - generate hash keys in-place
crypto: caam/qi2 - fix DMA mapping of stack memory
crypto: caam/qi2 - fix zero-length buffer DMA mapping
crypto: stm32/cryp - update to return iv_out
crypto: stm32/cryp - remove request mutex protection
crypto: stm32/cryp - add weak key check for DES
crypto: atmel - remove set but not used variable 'alg_name'
crypto: picoxcell - Use dev_get_drvdata()
crypto: crypto4xx - get rid of redundant using_sd variable
crypto: crypto4xx - use sync skcipher for fallback
crypto: crypto4xx - fix cfb and ofb "overran dst buffer" issues
crypto: crypto4xx - fix ctr-aes missing output IV
crypto: ecrdsa - select ASN1 and OID_REGISTRY for EC-RDSA
crypto: ux500 - use ccflags-y instead of CFLAGS_<basename>.o
crypto: ccree - handle tee fips error during power management resume
crypto: ccree - add function to handle cryptocell tee fips error
...
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.
With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP. These would all need to be fixed if any shash algorithm
actually started sleeping. For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API. However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.
Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk. It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.
Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Path lookups that traverse encrypted symlink(s) are very slow because
each encrypted symlink needs to be decrypted each time it's followed.
This also involves dropping out of rcu-walk mode.
Make encrypted symlinks faster by caching the decrypted symlink target
in ->i_link. The first call to fscrypt_get_symlink() sets it. Then,
the existing VFS path lookup code uses the non-NULL ->i_link to take the
fast path where ->get_link() isn't called, and lookups in rcu-walk mode
remain in rcu-walk mode.
Also set ->i_link immediately when a new encrypted symlink is created.
To safely free the symlink target after an RCU grace period has elapsed,
introduce a new function fscrypt_free_inode(), and make the relevant
filesystems call it just before actually freeing the inode.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
->lookup() in an encrypted directory begins as follows:
1. fscrypt_prepare_lookup():
a. Try to load the directory's encryption key.
b. If the key is unavailable, mark the dentry as a ciphertext name
via d_flags.
2. fscrypt_setup_filename():
a. Try to load the directory's encryption key.
b. If the key is available, encrypt the name (treated as a plaintext
name) to get the on-disk name. Otherwise decode the name
(treated as a ciphertext name) to get the on-disk name.
But if the key is concurrently added, it may be found at (2a) but not at
(1a). In this case, the dentry will be wrongly marked as a ciphertext
name even though it was actually treated as plaintext.
This will cause the dentry to be wrongly invalidated on the next lookup,
potentially causing problems. For example, if the racy ->lookup() was
part of sys_mount(), then the new mount will be detached when anything
tries to access it. This is despite the mountpoint having a plaintext
path, which should remain valid now that the key was added.
Of course, this is only possible if there's a userspace race. Still,
the additional kernel-side race is confusing and unexpected.
Close the kernel-side race by changing fscrypt_prepare_lookup() to also
set the on-disk filename (step 2b), consistent with the d_flags update.
Fixes: 28b4c26396 ("ext4 crypto: revalidate dentry after adding or removing the key")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
free the symlink body after the same RCU delay we have for freeing the
struct inode itself, so that traversal during RCU pathwalk wouldn't step
into freed memory.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
