If emergency system shutdown is called, like by thermal shutdown,
a dm device could be alive when the block device couldn't process
I/O requests anymore. In this state, the handling of I/O errors
by new dm I/O requests or by those already in-flight can lead to
a verity corruption state, which is a misjudgment.
So, skip verity work in response to I/O error when system is shutting
down.
Signed-off-by: Hyeongseok Kim <hyeongseok@gmail.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
bio-based code so that it follows patterns established by
request-based code.
- Request-based DM core improvement to eliminate unnecessary call to
blk_mq_queue_stopped().
- Add "panic_on_corruption" error handling mode to DM verity target.
- DM bufio fix to to perform buffer cleanup from a workqueue rather
than wait for IO in reclaim context from shrinker.
- DM crypt improvement to optionally avoid async processing via
workqueues for reads and/or writes -- via "no_read_workqueue" and
"no_write_workqueue" features. This more direct IO processing
improves latency and throughput with faster storage. Avoiding
workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is
a requirement for adding zoned block device support to DM crypt.
- Add zoned block device support to DM crypt. Makes use of
DM_CRYPT_NO_WRITE_WORKQUEUE and a new optional feature
(DM_CRYPT_WRITE_INLINE) that allows write completion to wait for
encryption to complete. This allows write ordering to be preserved,
which is needed for zoned block devices.
- Fix DM ebs target's check for REQ_OP_FLUSH.
- Fix DM core's report zones support to not report more zones than
were requested.
- A few small compiler warning fixes.
- DM dust improvements to return output directly to the user rather
than require they scrape the system log for output.
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Merge tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- DM multipath locking fixes around m->flags tests and improvements to
bio-based code so that it follows patterns established by
request-based code.
- Request-based DM core improvement to eliminate unnecessary call to
blk_mq_queue_stopped().
- Add "panic_on_corruption" error handling mode to DM verity target.
- DM bufio fix to to perform buffer cleanup from a workqueue rather
than wait for IO in reclaim context from shrinker.
- DM crypt improvement to optionally avoid async processing via
workqueues for reads and/or writes -- via "no_read_workqueue" and
"no_write_workqueue" features. This more direct IO processing
improves latency and throughput with faster storage. Avoiding
workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is a
requirement for adding zoned block device support to DM crypt.
- Add zoned block device support to DM crypt. Makes use of
DM_CRYPT_NO_WRITE_WORKQUEUE and a new optional feature
(DM_CRYPT_WRITE_INLINE) that allows write completion to wait for
encryption to complete. This allows write ordering to be preserved,
which is needed for zoned block devices.
- Fix DM ebs target's check for REQ_OP_FLUSH.
- Fix DM core's report zones support to not report more zones than were
requested.
- A few small compiler warning fixes.
- DM dust improvements to return output directly to the user rather
than require they scrape the system log for output.
* tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm: don't call report zones for more than the user requested
dm ebs: Fix incorrect checking for REQ_OP_FLUSH
dm init: Set file local variable static
dm ioctl: Fix compilation warning
dm raid: Remove empty if statement
dm verity: Fix compilation warning
dm crypt: Enable zoned block device support
dm crypt: add flags to optionally bypass kcryptd workqueues
dm bufio: do buffer cleanup from a workqueue
dm rq: don't call blk_mq_queue_stopped() in dm_stop_queue()
dm dust: add interface to list all badblocks
dm dust: report some message results directly back to user
dm verity: add "panic_on_corruption" error handling mode
dm mpath: use double checked locking in fast path
dm mpath: rename current_pgpath to pgpath in multipath_prepare_ioctl
dm mpath: rework __map_bio()
dm mpath: factor out multipath_queue_bio
dm mpath: push locking down to must_push_back_rq()
dm mpath: take m->lock spinlock when testing QUEUE_IF_NO_PATH
dm mpath: changes from initial m->flags locking audit
Samsung smart phones may need the ability to panic on corruption. Not
all devices provide the bootloader support needed to use the existing
"restart_on_corruption" mode. Additional details for why Samsung needs
this new mode can be found here:
https://www.redhat.com/archives/dm-devel/2020-June/msg00235.html
Signed-off-by: jhs2.lee <jhs2.lee@samsung.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Changes made during the 5.6 cycle warrant bumping the version number
for DM core and the targets modified by this commit.
It should be noted that dm-thin, dm-crypt and dm-raid already had
their target version bumped during the 5.6 merge window.
Signed-off-by; Mike Snitzer <snitzer@redhat.com>
Try to skip prefetching hash blocks that won't be needed due to the
"check_at_most_once" option being enabled and the corresponding data
blocks already having been verified.
Since prefetching operates on a range of data blocks, do this by just
trimming the two ends of the range. This doesn't skip every unneeded
hash block, since data blocks in the middle of the range could also be
unneeded, and hash blocks are still prefetched in large clusters as
controlled by dm_verity_prefetch_cluster. But it can still help a lot.
In a test on Android Q launching 91 apps every 15s repeated 21 times,
prefetching was only done for 447177/4776629 = 9.36% of data blocks.
Tested-by: ruxian.feng <ruxian.feng@transsion.com>
Co-developed-by: yuanjiong.gao <yuanjiong.gao@transsion.com>
Signed-off-by: yuanjiong.gao <yuanjiong.gao@transsion.com>
Signed-off-by: xianrong.zhou <xianrong.zhou@transsion.com>
[EB: simplified the 'while' loops and improved the commit message]
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The verification is to support cases where the root hash is not secured
by Trusted Boot, UEFI Secureboot or similar technologies.
One of the use cases for this is for dm-verity volumes mounted after
boot, the root hash provided during the creation of the dm-verity volume
has to be secure and thus in-kernel validation implemented here will be
used before we trust the root hash and allow the block device to be
created.
The signature being provided for verification must verify the root hash
and must be trusted by the builtin keyring for verification to succeed.
The hash is added as a key of type "user" and the description is passed
to the kernel so it can look it up and use it for verification.
Adds CONFIG_DM_VERITY_VERIFY_ROOTHASH_SIG which can be turned on if root
hash verification is needed.
Kernel commandline dm_verity module parameter 'require_signatures' will
indicate whether to force root hash signature verification (for all dm
verity volumes).
Signed-off-by: Jaskaran Khurana <jaskarankhurana@linux.microsoft.com>
Tested-and-Reviewed-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
DM verity should also use DMERR_LIMIT to limit repeat data block
corruption messages.
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Based on 1 normalized pattern(s):
this file is released under the gplv2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 68 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Log the hash algorithm's driver name when a dm-verity target is created.
This will help people determine whether the expected implementation is
being used. It can make an enormous difference; e.g., SHA-256 on ARM
can be 8x faster with the crypto extensions than without. It can also
be useful to know if an implementation using an external crypto
accelerator is being used instead of a software implementation.
Example message:
[ 35.281945] device-mapper: verity: sha256 using implementation "sha256-ce"
We've already found the similar message in fs/crypto/keyinfo.c to be
very useful.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Since commit d1ac3ff008 ("dm verity: switch to using asynchronous hash
crypto API") dm-verity uses asynchronous crypto calls for verification,
so that it can use hardware with asynchronous processing of crypto
operations.
These asynchronous calls don't support vmalloc memory, but the buffer data
can be allocated with vmalloc if dm-bufio is short of memory and uses a
reserved buffer that was preallocated in dm_bufio_client_create().
Fix verity_hash_update() so that it deals with vmalloc'd memory
correctly.
Reported-by: "Xiao, Jin" <jin.xiao@intel.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: d1ac3ff008 ("dm verity: switch to using asynchronous hash crypto API")
Cc: stable@vger.kernel.org # 4.12+
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use the fmode_t that is passed to dm_blk_ioctl() rather than
inconsistently (varies across targets) drop it on the floor by
overriding it with the fmode_t stored in 'struct dm_dev'.
All the persistent reservation functions weren't using the fmode_t they
got back from .prepare_ioctl so remove them.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fixes the following sparse warning:
drivers/md/dm-verity-target.c:375:6: warning:
symbol 'verity_for_io_block' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This allows platforms that are CPU/memory contrained to verify data
blocks only the first time they are read from the data device, rather
than every time. As such, it provides a reduced level of security
because only offline tampering of the data device's content will be
detected, not online tampering.
Hash blocks are still verified each time they are read from the hash
device, since verification of hash blocks is less performance critical
than data blocks, and a hash block will not be verified any more after
all the data blocks it covers have been verified anyway.
This option introduces a bitset that is used to check if a block has
been validated before or not. A block can be validated more than once
as there is no thread protection for the bitset.
These changes were developed and tested on entry-level Android Go
devices.
Signed-off-by: Patrik Torstensson <totte@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull crypto updates from Herbert Xu:
"Here is the crypto update for 4.15:
API:
- Disambiguate EBUSY when queueing crypto request by adding ENOSPC.
This change touches code outside the crypto API.
- Reset settings when empty string is written to rng_current.
Algorithms:
- Add OSCCA SM3 secure hash.
Drivers:
- Remove old mv_cesa driver (replaced by marvell/cesa).
- Enable rfc3686/ecb/cfb/ofb AES in crypto4xx.
- Add ccm/gcm AES in crypto4xx.
- Add support for BCM7278 in iproc-rng200.
- Add hash support on Exynos in s5p-sss.
- Fix fallback-induced error in vmx.
- Fix output IV in atmel-aes.
- Fix empty GCM hash in mediatek.
Others:
- Fix DoS potential in lib/mpi.
- Fix potential out-of-order issues with padata"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (162 commits)
lib/mpi: call cond_resched() from mpi_powm() loop
crypto: stm32/hash - Fix return issue on update
crypto: dh - Remove pointless checks for NULL 'p' and 'g'
crypto: qat - Clean up error handling in qat_dh_set_secret()
crypto: dh - Don't permit 'key' or 'g' size longer than 'p'
crypto: dh - Don't permit 'p' to be 0
crypto: dh - Fix double free of ctx->p
hwrng: iproc-rng200 - Add support for BCM7278
dt-bindings: rng: Document BCM7278 RNG200 compatible
crypto: chcr - Replace _manual_ swap with swap macro
crypto: marvell - Add a NULL entry at the end of mv_cesa_plat_id_table[]
hwrng: virtio - Virtio RNG devices need to be re-registered after suspend/resume
crypto: atmel - remove empty functions
crypto: ecdh - remove empty exit()
MAINTAINERS: update maintainer for qat
crypto: caam - remove unused param of ctx_map_to_sec4_sg()
crypto: caam - remove unneeded edesc zeroization
crypto: atmel-aes - Reset the controller before each use
crypto: atmel-aes - properly set IV after {en,de}crypt
hwrng: core - Reset user selected rng by writing "" to rng_current
...
dm-verity is starting async. crypto ops and waiting for them to complete.
Move it over to generic code doing the same.
This also avoids a future potential data coruption bug created
by the use of wait_for_completion_interruptible() without dealing
correctly with an interrupt aborting the wait prior to the
async op finishing, should this code ever move to a context
where signals are not masked.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
CC: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.
However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:
----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()
// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Constify a few variables in DM core and DM integrity
- Add bufio optimization and checksum failure accounting to DM integrity
- Fix DM integrity to avoid checking integrity of failed reads
- Fix DM integrity to use init_completion
- A couple DM log-writes target fixes
- Simplify DAX flushing by eliminating the unnecessary flush abstraction
that was stood up for DM's use.
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Merge tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- Some request-based DM core and DM multipath fixes and cleanups
- Constify a few variables in DM core and DM integrity
- Add bufio optimization and checksum failure accounting to DM
integrity
- Fix DM integrity to avoid checking integrity of failed reads
- Fix DM integrity to use init_completion
- A couple DM log-writes target fixes
- Simplify DAX flushing by eliminating the unnecessary flush
abstraction that was stood up for DM's use.
* tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dax: remove the pmem_dax_ops->flush abstraction
dm integrity: use init_completion instead of COMPLETION_INITIALIZER_ONSTACK
dm integrity: make blk_integrity_profile structure const
dm integrity: do not check integrity for failed read operations
dm log writes: fix >512b sectorsize support
dm log writes: don't use all the cpu while waiting to log blocks
dm ioctl: constify ioctl lookup table
dm: constify argument arrays
dm integrity: count and display checksum failures
dm integrity: optimize writing dm-bufio buffers that are partially changed
dm rq: do not update rq partially in each ending bio
dm rq: make dm-sq requeuing behavior consistent with dm-mq behavior
dm mpath: complain about unsupported __multipath_map_bio() return values
dm mpath: avoid that building with W=1 causes gcc 7 to complain about fall-through
The arrays of 'struct dm_arg' are never modified by the device-mapper
core, so constify them so that they are placed in .rodata.
(Exception: the args array in dm-raid cannot be constified because it is
allocated on the stack and modified.)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This way we don't need a block_device structure to submit I/O. The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open. Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).
For the actual I/O path all that we need is the gendisk, which exists
once per block device. But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.
Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'v4.12-rc5' into for-4.13/block
We've already got a few conflicts and upcoming work depends on some of the
changes that have gone into mainline as regression fixes for this series.
Pull in 4.12-rc5 to resolve these conflicts and make it easier on down stream
trees to continue working on 4.13 changes.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace bi_error with a new bi_status to allow for a clear conversion.
Note that device mapper overloaded bi_error with a private value, which
we'll have to keep arround at least for now and thus propagate to a
proper blk_status_t value.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Instead use the special DM_MAPIO_KILL return value to return -EIO just
like we do for the request based path. Note that dm-log-writes returned
-ENOMEM in a few places, which now becomes -EIO instead. No consumer
treats -ENOMEM special so this shouldn't be an issue (and it should
use a mempool to start with to make guaranteed progress).
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
DM-Verity has an (undocumented) mode where no salt is used. This was
never handled directly by the DM-Verity code, instead working due to the
fact that calling crypto_shash_update() with a zero length data is an
implicit noop.
This is no longer the case now that we have switched to
crypto_ahash_update(). Fix the issue by introducing explicit handling
of the no salt use case to DM-Verity.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Reported-by: Marian Csontos <mcsontos@redhat.com>
Fixes: d1ac3ff ("dm verity: switch to using asynchronous hash crypto API")
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use of the synchronous digest API limits dm-verity to using pure
CPU based algorithm providers and rules out the use of off CPU
algorithm providers which are normally asynchronous by nature,
potentially freeing CPU cycles.
This can reduce performance per Watt in situations such as during
boot time when a lot of concurrent file accesses are made to the
protected volume.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
CC: Eric Biggers <ebiggers3@gmail.com>
CC: Ondrej Mosnáček <omosnacek+linux-crypto@gmail.com>
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If ignore_zero_blocks is enabled dm-verity will return zeroes for blocks
matching a zero hash without validating the content.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add support for correcting corrupted blocks using Reed-Solomon.
This code uses RS(255, N) interleaved across data and hash
blocks. Each error-correcting block covers N bytes evenly
distributed across the combined total data, so that each byte is a
maximum distance away from the others. This makes it possible to
recover from several consecutive corrupted blocks with relatively
small space overhead.
In addition, using verity hashes to locate erasures nearly doubles
the effectiveness of error correction. Being able to detect
corrupted blocks also improves performance, because only corrupted
blocks need to corrected.
For a 2 GiB partition, RS(255, 253) (two parity bytes for each
253-byte block) can correct up to 16 MiB of consecutive corrupted
blocks if erasures can be located, and 8 MiB if they cannot, with
16 MiB space overhead.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
verity_for_bv_block() will be re-used by optional dm-verity object.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Prepare for an optional verity object to make use of existing dm-verity
structures and functions.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Prepare for extending dm-verity with an optional object. Follows the
naming convention used by other DM targets (e.g. dm-cache and dm-era).
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Hyeongseok Kim