This converts some of the visually simpler cases that have been split
over multiple lines. I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.
Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script. I probably had made it a bit _too_ trivial.
So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.
The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Avoid the relatively high overhead of constructing and walking per-page
segment bio_vecs for data unit alignment checking by merging the checks
into existing loops.
For hardware support crypto, perform the check in bio_split_io_at, which
already contains a similar alignment check applied for all I/O. This
means bio-based drivers that do not call bio_split_to_limits, should they
ever grow blk-crypto support, need to implement the check themselves,
just like all other queue limits checks.
For blk-crypto-fallback do it in the encryption/decryption loops. This
means alignment errors for decryption will only be detected after I/O
has completed, but that seems like a worthwhile trade off.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Calling mempool_alloc in a loop is not safe unless the maximum allocation
size times the maximum number of threads using it is less than the
minimum pool size. Use the new mempool_alloc_bulk helper to allocate
all missing elements in one pass to remove this deadlock risk. This
also means that non-pool allocations now use alloc_pages_bulk which can
be significantly faster than a loop over individual page allocations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allocating a skcipher request dynamically can deadlock or cause
unexpected I/O failures when called from writeback context. Avoid the
allocation entirely by using on-stack skciphers, similar to what the
non-blk-crypto fscrypt path already does.
This drops the incomplete support for asynchronous algorithms, which
previously could be used, but only synchronously.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The current code in blk_crypto_fallback_encrypt_bio is inefficient and
prone to deadlocks under memory pressure: It first walks the passed in
plaintext bio to see how much of it can fit into a single encrypted
bio using up to BIO_MAX_VEC PAGE_SIZE segments, and then allocates a
plaintext clone that fits the size, only to allocate another bio for
the ciphertext later. While the plaintext clone uses a bioset to avoid
deadlocks when allocations could fail, the ciphertex one uses bio_kmalloc
which is a no-go in the file system I/O path.
Switch blk_crypto_fallback_encrypt_bio to walk the source plaintext bio
while consuming bi_iter without cloning it, and instead allocate a
ciphertext bio at the beginning and whenever we fille up the previous
one. The existing bio_set for the plaintext clones is reused for the
ciphertext bios to remove the deadlock risk.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Restructure blk_crypto_fallback_bio_prep so that it always submits the
encrypted bio instead of passing it back to the caller, which allows
to simplify the calling conventions for blk_crypto_fallback_bio_prep and
blk_crypto_bio_prep so that they never have to return a bio, and can
use a true return value to indicate that the caller should submit the
bio, and false that the blk-crypto code consumed it.
The submission is handled by the on-stack bio list in the current
task_struct by the block layer and does not cause additional stack
usage or major overhead. It also prepares for the following optimization
and fixes for the blk-crypto fallback write path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
trace_block_split() is missing, resulting in blktrace inability to catch
BIO split events and making it harder to analyze the BIO sequence.
Cc: stable@vger.kernel.org
Fixes: 488f6682c8 ("block: blk-crypto-fallback for Inline Encryption")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just a simpler wrapper around bio_init for callers that want to
initialize a bio with inline bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To prevent keys from being compromised if an attacker acquires read
access to kernel memory, some inline encryption hardware can accept keys
which are wrapped by a per-boot hardware-internal key. This avoids
needing to keep the raw keys in kernel memory, without limiting the
number of keys that can be used. Such hardware also supports deriving a
"software secret" for cryptographic tasks that can't be handled by
inline encryption; this is needed for fscrypt to work properly.
To support this hardware, allow struct blk_crypto_key to represent a
hardware-wrapped key as an alternative to a raw key, and make drivers
set flags in struct blk_crypto_profile to indicate which types of keys
they support. Also add the ->derive_sw_secret() low-level operation,
which drivers supporting wrapped keys must implement.
For more information, see the detailed documentation which this patch
adds to Documentation/block/inline-encryption.rst.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> # sm8650
Link: https://lore.kernel.org/r/20250204060041.409950-2-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Instead of returning an inconclusive value of NULL for an error in calling
bio_split(), return a ERR_PTR() always.
Also remove the BUG_ON() calls, and WARN_ON_ONCE() instead. Indeed, since
almost all callers don't check the return code from bio_split(), we'll
crash anyway (for those failures).
Fix up the only user which checks bio_split() return code today (directly
or indirectly), blk_crypto_fallback_split_bio_if_needed(). The md/bcache
code does check the return code in cached_dev_cache_miss() ->
bio_next_split() -> bio_split(), but only to see if there was a split, so
there would be no change in behaviour here (when returning a ERR_PTR()).
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20241111112150.3756529-2-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Restore support for passing data lifetime information from filesystems to
block drivers. This patch reverts commit b179c98f76 ("block: Remove
request.write_hint") and commit c75e707fe1 ("block: remove the
per-bio/request write hint").
This patch does not modify the size of struct bio because the new
bi_write_hint member fills a hole in struct bio. pahole reports the
following for struct bio on an x86_64 system with this patch applied:
/* size: 112, cachelines: 2, members: 20 */
/* sum members: 110, holes: 1, sum holes: 2 */
/* last cacheline: 48 bytes */
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240202203926.2478590-7-bvanassche@acm.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
blk_crypto_profile_init() calls lockdep_register_key(), which warns and
does not register if the provided memory is a static object.
blk-crypto-fallback currently has a static blk_crypto_profile and calls
blk_crypto_profile_init() thereupon, resulting in the warning and
failure to register.
Fortunately it is simple enough to use a dynamically allocated profile
and make lockdep function correctly.
Fixes: 2fb48d88e7 ("blk-crypto: use dynamic lock class for blk_crypto_profile::lock")
Cc: stable@vger.kernel.org
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20230817141615.15387-1-sweettea-kernel@dorminy.me
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The prandom_bytes() function has been a deprecated inline wrapper around
get_random_bytes() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. This was done as a basic find and replace.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> # powerpc
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
blk_keyslot_manager is misnamed because it doesn't necessarily manage
keyslots. It actually does several different things:
- Contains the crypto capabilities of the device.
- Provides functions to control the inline encryption hardware.
Originally these were just for programming/evicting keyslots;
however, new functionality (hardware-wrapped keys) will require new
functions here which are unrelated to keyslots. Moreover,
device-mapper devices already (ab)use "keyslot_evict" to pass key
eviction requests to their underlying devices even though
device-mapper devices don't have any keyslots themselves (so it
really should be "evict_key", not "keyslot_evict").
- Sometimes (but not always!) it manages keyslots. Originally it
always did, but device-mapper devices don't have keyslots
themselves, so they use a "passthrough keyslot manager" which
doesn't actually manage keyslots. This hack works, but the
terminology is unnatural. Also, some hardware doesn't have keyslots
and thus also uses a "passthrough keyslot manager" (support for such
hardware is yet to be upstreamed, but it will happen eventually).
Let's stop having keyslot managers which don't actually manage keyslots.
Instead, rename blk_keyslot_manager to blk_crypto_profile.
This is a fairly big change, since for consistency it also has to update
keyslot manager-related function names, variable names, and comments --
not just the actual struct name. However it's still a fairly
straightforward change, as it doesn't change any actual functionality.
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20211018180453.40441-4-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For clarity, avoid using just the "blk_crypto_" prefix for functions and
structs that are specific to blk-crypto-fallback. Instead, use
"blk_crypto_fallback_". Some places already did this, but others
didn't.
This is also a prerequisite for using "struct blk_crypto_keyslot" to
mean a generic blk-crypto keyslot (which is what it sounds like).
Rename the fallback one to "struct blk_crypto_fallback_keyslot".
No change in behavior.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20211018180453.40441-2-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
