Rename fscrypt_encrypt_page() to fscrypt_encrypt_pagecache_blocks() and
redefine its behavior to encrypt all filesystem blocks from the given
region of the given page, rather than assuming that the region consists
of just one filesystem block. Also remove the 'inode' and 'lblk_num'
parameters, since they can be retrieved from the page as it's already
assumed to be a pagecache page.
This is in preparation for allowing encryption on ext4 filesystems with
blocksize != PAGE_SIZE.
This is based on work by Chandan Rajendra.
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>
Replace some BUG_ON()s with WARN_ON_ONCE() and returning an error code,
and move the check for len divisible by FS_CRYPTO_BLOCK_SIZE into
fscrypt_crypt_block() so that it's done for both encryption and
decryption, not just encryption.
Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
fscrypt_do_page_crypto() only does a single encryption or decryption
operation, with a single logical block number (single IV). So it
actually operates on a filesystem block, not a "page" per se. To
reflect this, rename it to fscrypt_crypt_block().
Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Now that fscrypt_ctx is not used for writes, remove the 'w' fields.
Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Currently, bounce page handling for writes to encrypted files is
unnecessarily complicated. A fscrypt_ctx is allocated along with each
bounce page, page_private(bounce_page) points to this fscrypt_ctx, and
fscrypt_ctx::w::control_page points to the original pagecache page.
However, because writes don't use the fscrypt_ctx for anything else,
there's no reason why page_private(bounce_page) can't just point to the
original pagecache page directly.
Therefore, this patch makes this change. In the process, it also cleans
up the API exposed to filesystems that allows testing whether a page is
a bounce page, getting the pagecache page from a bounce page, and
freeing a bounce page.
Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file
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>
Make various improvements to fscrypt dentry revalidation:
- Don't try to handle the case where the per-directory key is removed,
as this can't happen without the inode (and dentries) being evicted.
- Flag ciphertext dentries rather than plaintext dentries, since it's
ciphertext dentries that need the special handling.
- Avoid doing unnecessary work for non-ciphertext dentries.
- When revalidating ciphertext dentries, try to set up the directory's
i_crypt_info to make sure the key is really still absent, rather than
invalidating all negative dentries as the previous code did. An old
comment suggested we can't do this for locking reasons, but AFAICT
this comment was outdated and it actually works fine.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
->i_crypt_info starts out NULL and may later be locklessly set to a
non-NULL value by the cmpxchg() in fscrypt_get_encryption_info().
But ->i_crypt_info is used directly, which technically is incorrect.
It's a data race, and it doesn't include the data dependency barrier
needed to safely dereference the pointer on at least one architecture.
Fix this by using READ_ONCE() instead. Note: we don't need to use
smp_load_acquire(), since dereferencing the pointer only requires a data
dependency barrier, which is already included in READ_ONCE(). We also
don't need READ_ONCE() in places where ->i_crypt_info is unconditionally
dereferenced, since it must have already been checked.
Also downgrade the cmpxchg() to cmpxchg_release(), since RELEASE
semantics are sufficient on the write side.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The only reason the inode is being passed to fscrypt_get_ctx() is to
verify that the encryption key is available. However, all callers
already ensure this because if we get as far as trying to do I/O to an
encrypted file without the key, there's already a bug.
Therefore, remove this unnecessary argument.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Add support for the Adiantum encryption mode to fscrypt. Adiantum is a
tweakable, length-preserving encryption mode with security provably
reducible to that of XChaCha12 and AES-256, subject to a security bound.
It's also a true wide-block mode, unlike XTS. See the paper
"Adiantum: length-preserving encryption for entry-level processors"
(https://eprint.iacr.org/2018/720.pdf) for more details. Also see
commit 059c2a4d8e ("crypto: adiantum - add Adiantum support").
On sufficiently long messages, Adiantum's bottlenecks are XChaCha12 and
the NH hash function. These algorithms are fast even on processors
without dedicated crypto instructions. Adiantum makes it feasible to
enable storage encryption on low-end mobile devices that lack AES
instructions; currently such devices are unencrypted. On ARM Cortex-A7,
on 4096-byte messages Adiantum encryption is about 4 times faster than
AES-256-XTS encryption; decryption is about 5 times faster.
In fscrypt, Adiantum is suitable for encrypting both file contents and
names. With filenames, it fixes a known weakness: when two filenames in
a directory share a common prefix of >= 16 bytes, with CTS-CBC their
encrypted filenames share a common prefix too, leaking information.
Adiantum does not have this problem.
Since Adiantum also accepts long tweaks (IVs), it's also safe to use the
master key directly for Adiantum encryption rather than deriving
per-file keys, provided that the per-file nonce is included in the IVs
and the master key isn't used for any other encryption mode. This
configuration saves memory and improves performance. A new fscrypt
policy flag is added to allow users to opt-in to this configuration.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In this round, we've mainly focused on discard, aka unmap, control along with
fstrim for Android-specific usage model. In addition, we've fixed writepage flow
which returned EAGAIN previously resulting in EIO of fsync(2) due to mapping's
error state. In order to avoid old MM bug [1], we decided not to use __GFP_ZERO
for the mapping for node and meta page caches. As always, we've cleaned up many
places for future fsverity and symbol conflicts.
Enhancement:
- do discard/fstrim in lower priority considering fs utilization
- split large discard commands into smaller ones for better responsiveness
- add more sanity checks to address syzbot reports
- add a mount option, fsync_mode=nobarrier, which can reduce # of cache flushes
- clean up symbol namespace with modified function names
- be strict on block allocation and IO control in corner cases
Bug fix:
- don't use __GFP_ZERO for mappings
- fix error reports in writepage to avoid fsync() failure
- avoid selinux denial on CAP_RESOURCE on resgid/resuid
- fix some subtle race conditions in GC/atomic writes/shutdown
- fix overflow bugs in sanity_check_raw_super
- fix missing bits on get_flags
Clean-up:
- prepare the generic flow for future fsverity integration
- fix some broken coding standard
[1] https://lkml.org/lkml/2018/4/8/661
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Merge tag 'f2fs-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've mainly focused on discard, aka unmap, control
along with fstrim for Android-specific usage model. In addition, we've
fixed writepage flow which returned EAGAIN previously resulting in EIO
of fsync(2) due to mapping's error state. In order to avoid old MM bug
[1], we decided not to use __GFP_ZERO for the mapping for node and
meta page caches. As always, we've cleaned up many places for future
fsverity and symbol conflicts.
Enhancements:
- do discard/fstrim in lower priority considering fs utilization
- split large discard commands into smaller ones for better responsiveness
- add more sanity checks to address syzbot reports
- add a mount option, fsync_mode=nobarrier, which can reduce # of cache flushes
- clean up symbol namespace with modified function names
- be strict on block allocation and IO control in corner cases
Bug fixes:
- don't use __GFP_ZERO for mappings
- fix error reports in writepage to avoid fsync() failure
- avoid selinux denial on CAP_RESOURCE on resgid/resuid
- fix some subtle race conditions in GC/atomic writes/shutdown
- fix overflow bugs in sanity_check_raw_super
- fix missing bits on get_flags
Clean-ups:
- prepare the generic flow for future fsverity integration
- fix some broken coding standard"
[1] https://lkml.org/lkml/2018/4/8/661
* tag 'f2fs-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (79 commits)
f2fs: fix to clear FI_VOLATILE_FILE correctly
f2fs: let sync node IO interrupt async one
f2fs: don't change wbc->sync_mode
f2fs: fix to update mtime correctly
fs: f2fs: insert space around that ':' and ', '
fs: f2fs: add missing blank lines after declarations
fs: f2fs: changed variable type of offset "unsigned" to "loff_t"
f2fs: clean up symbol namespace
f2fs: make set_de_type() static
f2fs: make __f2fs_write_data_pages() static
f2fs: fix to avoid accessing cross the boundary
f2fs: fix to let caller retry allocating block address
disable loading f2fs module on PAGE_SIZE > 4KB
f2fs: fix error path of move_data_page
f2fs: don't drop dentry pages after fs shutdown
f2fs: fix to avoid race during access gc_thread pointer
f2fs: clean up with clear_radix_tree_dirty_tag
f2fs: fix to don't trigger writeback during recovery
f2fs: clear discard_wake earlier
f2fs: let discard thread wait a little longer if dev is busy
...
Use a common function for fscrypt warning and error messages so that all
the messages are consistently ratelimited, include the "fscrypt:"
prefix, and include the filesystem name if applicable.
Also fix up a few of the log messages to be more descriptive.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
skcipher_request_alloc() can only fail due to lack of memory, and in
that case the memory allocator will have already printed a detailed
error message. Thus, remove the redundant error messages from fscrypt.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now that all filesystems have been converted to use
fscrypt_prepare_lookup(), we can remove the fscrypt_set_d_op() and
fscrypt_set_encrypted_dentry() functions as well as un-export
fscrypt_d_ops.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Improve fscrypt read performance by switching the decryption workqueue
from bound to unbound. With the bound workqueue, when multiple bios
completed on the same CPU, they were decrypted on that same CPU. But
with the unbound queue, they are now decrypted in parallel on any CPU.
Although fscrypt read performance can be tough to measure due to the
many sources of variation, this change is most beneficial when
decryption is slow, e.g. on CPUs without AES instructions. For example,
I timed tarring up encrypted directories on f2fs. On x86 with AES-NI
instructions disabled, the unbound workqueue improved performance by
about 25-35%, using 1 to NUM_CPUs jobs with 4 or 8 CPUs available. But
with AES-NI enabled, performance was unchanged to within ~2%.
I also did the same test on a quad-core ARM CPU using xts-speck128-neon
encryption. There performance was usually about 10% better with the
unbound workqueue, bringing it closer to the unencrypted speed.
The unbound workqueue may be worse in some cases due to worse locality,
but I think it's still the better default. dm-crypt uses an unbound
workqueue by default too, so this change makes fscrypt match.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently, fscrypt provides fscrypt_decrypt_bio_pages() which decrypts a
bio's pages asynchronously, then unlocks them afterwards. But, this
assumes that decryption is the last "postprocessing step" for the bio,
so it's incompatible with additional postprocessing steps such as
authenticity verification after decryption.
Therefore, rename the existing fscrypt_decrypt_bio_pages() to
fscrypt_enqueue_decrypt_bio(). Then, add fscrypt_decrypt_bio() which
decrypts the pages in the bio synchronously without unlocking the pages,
nor setting them Uptodate; and add fscrypt_enqueue_decrypt_work(), which
enqueues work on the fscrypt_read_workqueue. The new functions will be
used by filesystems that support both fscrypt and fs-verity.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
fscrypt.h included way too many other headers, given that it is included
by filesystems both with and without encryption support. Trim down the
includes list by moving the needed includes into more appropriate
places, and removing the unneeded ones.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt
Pull fscrypt updates from Ted Ts'o:
"Lots of cleanups, mostly courtesy by Eric Biggers"
* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt:
fscrypt: lock mutex before checking for bounce page pool
fscrypt: add a documentation file for filesystem-level encryption
ext4: switch to fscrypt_prepare_setattr()
ext4: switch to fscrypt_prepare_lookup()
ext4: switch to fscrypt_prepare_rename()
ext4: switch to fscrypt_prepare_link()
ext4: switch to fscrypt_file_open()
fscrypt: new helper function - fscrypt_prepare_setattr()
fscrypt: new helper function - fscrypt_prepare_lookup()
fscrypt: new helper function - fscrypt_prepare_rename()
fscrypt: new helper function - fscrypt_prepare_link()
fscrypt: new helper function - fscrypt_file_open()
fscrypt: new helper function - fscrypt_require_key()
fscrypt: remove unneeded empty fscrypt_operations structs
fscrypt: remove ->is_encrypted()
fscrypt: switch from ->is_encrypted() to IS_ENCRYPTED()
fs, fscrypt: add an S_ENCRYPTED inode flag
fscrypt: clean up include file mess
fscrypt starts several async. crypto ops and waiting for them to
complete. Move it over to generic code doing the same.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
fscrypt_initialize(), which allocates the global bounce page pool when
an encrypted file is first accessed, uses "double-checked locking" to
try to avoid locking fscrypt_init_mutex. However, it doesn't use any
memory barriers, so it's theoretically possible for a thread to observe
a bounce page pool which has not been fully initialized. This is a
classic bug with "double-checked locking".
While "only a theoretical issue" in the latest kernel, in pre-4.8
kernels the pointer that was checked was not even the last to be
initialized, so it was easily possible for a crash (NULL pointer
dereference) to happen. This was changed only incidentally by the large
refactor to use fs/crypto/.
Solve both problems in a trivial way that can easily be backported: just
always take the mutex. It's theoretically less efficient, but it
shouldn't be noticeable in practice as the mutex is only acquired very
briefly once per encrypted file.
Later I'd like to make this use a helper macro like DO_ONCE(). However,
DO_ONCE() runs in atomic context, so we'd need to add a new macro that
allows blocking.
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
IS_ENCRYPTED() now gives the same information as
i_sb->s_cop->is_encrypted() but is more efficient, since IS_ENCRYPTED()
is just a simple flag check. Prepare to remove ->is_encrypted() by
switching all callers to IS_ENCRYPTED().
Acked-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fscrypt provides facilities to use different encryption algorithms which
are selectable by userspace when setting the encryption policy. Currently,
only AES-256-XTS for file contents and AES-256-CBC-CTS for file names are
implemented. This is a clear case of kernel offers the mechanism and
userspace selects a policy. Similar to what dm-crypt and ecryptfs have.
This patch adds support for using AES-128-CBC for file contents and
AES-128-CBC-CTS for file name encryption. To mitigate watermarking
attacks, IVs are generated using the ESSIV algorithm. While AES-CBC is
actually slightly less secure than AES-XTS from a security point of view,
there is more widespread hardware support. Using AES-CBC gives us the
acceptable performance while still providing a moderate level of security
for persistent storage.
Especially low-powered embedded devices with crypto accelerators such as
CAAM or CESA often only support AES-CBC. Since using AES-CBC over AES-XTS
is basically thought of a last resort, we use AES-128-CBC over AES-256-CBC
since it has less encryption rounds and yields noticeable better
performance starting from a file size of just a few kB.
Signed-off-by: Daniel Walter <dwalter@sigma-star.at>
[david@sigma-star.at: addressed review comments]
Signed-off-by: David Gstir <david@sigma-star.at>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Filesystem encryption ostensibly supported revoking a keyring key that
had been used to "unlock" encrypted files, causing those files to become
"locked" again. This was, however, buggy for several reasons, the most
severe of which was that when key revocation happened to be detected for
an inode, its fscrypt_info was immediately freed, even while other
threads could be using it for encryption or decryption concurrently.
This could be exploited to crash the kernel or worse.
This patch fixes the use-after-free by removing the code which detects
the keyring key having been revoked, invalidated, or expired. Instead,
an encrypted inode that is "unlocked" now simply remains unlocked until
it is evicted from memory. Note that this is no worse than the case for
block device-level encryption, e.g. dm-crypt, and it still remains
possible for a privileged user to evict unused pages, inodes, and
dentries by running 'sync; echo 3 > /proc/sys/vm/drop_caches', or by
simply unmounting the filesystem. In fact, one of those actions was
already needed anyway for key revocation to work even somewhat sanely.
This change is not expected to break any applications.
In the future I'd like to implement a real API for fscrypt key
revocation that interacts sanely with ongoing filesystem operations ---
waiting for existing operations to complete and blocking new operations,
and invalidating and sanitizing key material and plaintext from the VFS
caches. But this is a hard problem, and for now this bug must be fixed.
This bug affected almost all versions of ext4, f2fs, and ubifs
encryption, and it was potentially reachable in any kernel configured
with encryption support (CONFIG_EXT4_ENCRYPTION=y,
CONFIG_EXT4_FS_ENCRYPTION=y, CONFIG_F2FS_FS_ENCRYPTION=y, or
CONFIG_UBIFS_FS_ENCRYPTION=y). Note that older kernels did not use the
shared fs/crypto/ code, but due to the potential security implications
of this bug, it may still be worthwhile to backport this fix to them.
Fixes: b7236e21d5 ("ext4 crypto: reorganize how we store keys in the inode")
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: Michael Halcrow <mhalcrow@google.com>
That way we can get rid of the direct dependency on CONFIG_BLOCK.
Fixes: d475a50745 ("ubifs: Add skeleton for fscrypto")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
... to better explain its purpose after introducing in-place encryption
without bounce buffer.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Since fscrypt users can now indicated if fscrypt_encrypt_page() should
use a bounce page, we can delay the bounce page pool initialization util
it is really needed. That is until fscrypt_operations has no
FS_CFLG_OWN_PAGES flag set.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Rename the FS_CFLG_INPLACE_ENCRYPTION flag to FS_CFLG_OWN_PAGES which,
when set, indicates that the fs uses pages under its own control as
opposed to writeback pages which require locking and a bounce buffer for
encryption.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In case of in-place encryption fscrypt_ctx was allocated but never
released. Since we don't need it for in-place encryption, we skip
allocating it.
Fixes: 1c7dcf69ee ("fscrypt: Add in-place encryption mode")
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Actually use the fs-provided index instead of always using page->index
which is only set for page-cache pages.
Fixes: 9c4bb8a3a9 ("fscrypt: Let fs select encryption index/tweak")
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The fscrypt_initalize() function isn't used outside fs/crypto, so
there's no point making it be an exported symbol.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Avoid re-use of page index as tweak for AES-XTS when multiple parts of
same page are encrypted. This will happen on multiple (partial) calls of
fscrypt_encrypt_page on same page.
page->index is only valid for writeback pages.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Some filesystems, such as UBIFS, maintain a const pointer for struct
inode.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Not all filesystems work on full pages, thus we should allow them to
hand partial pages to fscrypt for en/decryption.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Some filesystem might pass pages which do not have page->mapping->host
set to the encrypted inode. We want the caller to explicitly pass the
corresponding inode.
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4 and f2fs require a bounce page when encrypting pages. However, not
all filesystems will need that (eg. UBIFS). This is handled via a
flag on fscrypt_operations where a fs implementation can select in-place
encryption over using a bounce page (which is the default).
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The XTS tweak (or IV) was initialized differently on little endian and
big endian systems. Because the ciphertext depends on the XTS tweak, it
was not possible to use an encrypted filesystem created by a little
endian system on a big endian system and vice versa, even if they shared
the same PAGE_SIZE. Fix this by always using little endian.
This will break hypothetical big endian users of ext4 or f2fs
encryption. However, all users we are aware of are little endian, and
it's believed that "real" big endian users are unlikely to exist yet.
So this might as well be fixed now before it's too late.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
fscrypt_complete() was used only for data pages, not for all
encryption/decryption. Rename it to page_crypt_complete().
dir_crypt_complete() was used for filename encryption/decryption for
both directory entries and symbolic links. Rename it to
fname_crypt_complete().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch removes some #includes that are clearly not needed, such as a
reference to ecryptfs, which is unrelated to the new filesystem
encryption code.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch converts the simple bi_rw use cases in the block,
drivers, mm and fs code to set/get the bio operation using
bio_set_op_attrs/bio_op
These should be simple one or two liner cases, so I just did them
in one patch. The next patches handle the more complicated
cases in a module per patch.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This has callers of submit_bio/submit_bio_wait set the bio->bi_rw
instead of passing it in. This makes that use the same as
generic_make_request and how we set the other bio fields.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Fixed up fs/ext4/crypto.c
Signed-off-by: Jens Axboe <axboe@fb.com>
As Al pointed, d_revalidate should return RCU lookup before using d_inode.
This was originally introduced by:
commit 34286d6662 ("fs: rcu-walk aware d_revalidate method").
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: stable <stable@vger.kernel.org>
This patch fixes the issue introduced by the ext4 crypto fix in a same manner.
For F2FS, however, we flush the pending IOs and wait for a while to acquire free
memory.
Fixes: c9af28fdd4 ("ext4 crypto: don't let data integrity writebacks fail with ENOMEM")
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch updates fscrypto along with the below ext4 crypto change.
Fixes: 3d43bcfef5 ("ext4 crypto: use dget_parent() in ext4_d_revalidate()")
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are
not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.
The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.
There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.
virtual patch
@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT
@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE
@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK
@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)
@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)
@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 0b81d07790 ("fs crypto: move per-file encryption from f2fs
tree to fs/crypto") moved the f2fs crypto files to fs/crypto/ and
renamed the symbol prefixes from "f2fs_" to "fscrypt_" (and from "F2FS_"
to just "FS" for preprocessor symbols).
Because of the symbol renaming, it's a bit hard to see it as a file
move: use
git show -M30 0b81d07790
to lower the rename detection to just 30% similarity and make git show
the files as renamed (the header file won't be shown as a rename even
then - since all it contains is symbol definitions, it looks almost
completely different).
Even with the renames showing as renames, the diffs are not all that
easy to read, since so much is just the renames. But Eric Biggers
noticed that it's not just all renames: the initialization of the
xts_tweak had been broken too, using the inode number rather than the
page offset.
That's not right - it makes the xfs_tweak the same for all pages of each
inode. It _might_ make sense to make the xfs_tweak contain both the
offset _and_ the inode number, but not just the inode number.
Reported-by: Eric Biggers <ebiggers3@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull f2fs updates from Jaegeuk Kim:
"New Features:
- uplift filesystem encryption into fs/crypto/
- give sysfs entries to control memroy consumption
Enhancements:
- aio performance by preallocating blocks in ->write_iter
- use writepages lock for only WB_SYNC_ALL
- avoid redundant inline_data conversion
- enhance forground GC
- use wait_for_stable_page as possible
- speed up SEEK_DATA and fiiemap
Bug Fixes:
- corner case in terms of -ENOSPC for inline_data
- hung task caused by long latency in shrinker
- corruption between atomic write and f2fs_trace_pid
- avoid garbage lengths in dentries
- revoke atomicly written pages if an error occurs
In addition, there are various minor bug fixes and clean-ups"
* tag 'for-f2fs-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (81 commits)
f2fs: submit node page write bios when really required
f2fs: add missing argument to f2fs_setxattr stub
f2fs: fix to avoid unneeded unlock_new_inode
f2fs: clean up opened code with f2fs_update_dentry
f2fs: declare static functions
f2fs: use cryptoapi crc32 functions
f2fs: modify the readahead method in ra_node_page()
f2fs crypto: sync ext4_lookup and ext4_file_open
fs crypto: move per-file encryption from f2fs tree to fs/crypto
f2fs: mutex can't be used by down_write_nest_lock()
f2fs: recovery missing dot dentries in root directory
f2fs: fix to avoid deadlock when merging inline data
f2fs: introduce f2fs_flush_merged_bios for cleanup
f2fs: introduce f2fs_update_data_blkaddr for cleanup
f2fs crypto: fix incorrect positioning for GCing encrypted data page
f2fs: fix incorrect upper bound when iterating inode mapping tree
f2fs: avoid hungtask problem caused by losing wake_up
f2fs: trace old block address for CoWed page
f2fs: try to flush inode after merging inline data
f2fs: show more info about superblock recovery
...
Eric Biggers
Thomas Gleixner
Linus Torvalds
Gilad Ben-Yossef
Daniel Walter
Richard Weinberger
David Gstir
Theodore Ts'o
Mike Christie
Jaegeuk Kim
Kirill A. Shutemov