Eliminate duplicate boilerplate code for simple modules that contain
a single DM target driver without any additional setup code.
Add a new module_dm() macro, which replaces the module_init() and
module_exit() with template functions that call dm_register_target()
and dm_unregister_target() respectively.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Simplifies each DM target's init method by making dm_register_target()
responsible for its error reporting (on behalf of targets).
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
target flag (initially added to allow swap to dm-crypt) to throttle
the amount of outstanding swap bios.
- Fix DM crypt soft lockup warnings by calling cond_resched() from the
cpu intensive loop in dmcrypt_write().
- Fix DM crypt to not access an uninitialized tasklet. This fix allows
for consistent handling of IO completion, by _not_ needlessly punting
to a workqueue when tasklets are not needed.
- Fix DM core's alloc_dev() initialization for DM stats to check for
and propagate alloc_percpu() failure.
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Merge tag 'for-6.3/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- Fix DM thin to work as a swap device by using 'limit_swap_bios' DM
target flag (initially added to allow swap to dm-crypt) to throttle
the amount of outstanding swap bios.
- Fix DM crypt soft lockup warnings by calling cond_resched() from the
cpu intensive loop in dmcrypt_write().
- Fix DM crypt to not access an uninitialized tasklet. This fix allows
for consistent handling of IO completion, by _not_ needlessly punting
to a workqueue when tasklets are not needed.
- Fix DM core's alloc_dev() initialization for DM stats to check for
and propagate alloc_percpu() failure.
* tag 'for-6.3/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm stats: check for and propagate alloc_percpu failure
dm crypt: avoid accessing uninitialized tasklet
dm crypt: add cond_resched() to dmcrypt_write()
dm thin: fix deadlock when swapping to thin device
When neither "no_read_workqueue" nor "no_write_workqueue" are enabled,
tasklet_trylock() in crypt_dec_pending() may still return false due to
an uninitialized state, and dm-crypt will unnecessarily do io completion
in io_queue workqueue instead of current context.
Fix this by adding an 'in_tasklet' flag to dm_crypt_io struct and
initialize it to false in crypt_io_init(). Set this flag to true in
kcryptd_queue_crypt() before calling tasklet_schedule(). If set
crypt_dec_pending() will punt io completion to a workqueue.
This also nicely avoids the tasklet_trylock/unlock hack when tasklets
aren't in use.
Fixes: 8e14f61015 ("dm crypt: do not call bio_endio() from the dm-crypt tasklet")
Cc: stable@vger.kernel.org
Reported-by: Hou Tao <houtao1@huawei.com>
Suggested-by: Ignat Korchagin <ignat@cloudflare.com>
Reviewed-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
slab BUG will occur when kmem_cache_destroy() is called.
- Improve 2 of DM's shrinker names to reflect their use.
- Fix the DM flakey target to not corrupt the zero page. Fix dm-flakey
on 32-bit hughmem systems by using bvec_kmap_local instead of
page_address. Also, fix logic used when imposing the
"corrupt_bio_byte" feature.
- Stop using WQ_UNBOUND for DM verity target's verify_wq because it
causes significant Android latencies on ARM64 (and doesn't show real
benefit on other architectures).
- Add negative check to catch simple case of a DM table referencing
itself. More complex scenarios that use intermediate devices to
self-reference still need to be avoided/handled in userspace.
- Fix DM core's resize to only send one uevent instead of two. This
fixes a race with udev, that if udev wins, will cause udev to miss
uevents (which caused premature unmount attempts by systemd).
- Add cond_resched() to workqueue functions in DM core, dn-thin and
dm-cache so that their loops aren't the cause of unintended cpu
scheduling fairness issues.
- Fix all of DM's checkpatch errors and warnings (famous last words).
Various other small cleanups.
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Merge tag 'for-6.3/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- Fix DM cache target to free background tracker work items, otherwise
slab BUG will occur when kmem_cache_destroy() is called.
- Improve 2 of DM's shrinker names to reflect their use.
- Fix the DM flakey target to not corrupt the zero page. Fix dm-flakey
on 32-bit hughmem systems by using bvec_kmap_local instead of
page_address. Also, fix logic used when imposing the
"corrupt_bio_byte" feature.
- Stop using WQ_UNBOUND for DM verity target's verify_wq because it
causes significant Android latencies on ARM64 (and doesn't show real
benefit on other architectures).
- Add negative check to catch simple case of a DM table referencing
itself. More complex scenarios that use intermediate devices to
self-reference still need to be avoided/handled in userspace.
- Fix DM core's resize to only send one uevent instead of two. This
fixes a race with udev, that if udev wins, will cause udev to miss
uevents (which caused premature unmount attempts by systemd).
- Add cond_resched() to workqueue functions in DM core, dn-thin and
dm-cache so that their loops aren't the cause of unintended cpu
scheduling fairness issues.
- Fix all of DM's checkpatch errors and warnings (famous last words).
Various other small cleanups.
* tag 'for-6.3/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (62 commits)
dm: remove unnecessary (void*) conversion in event_callback()
dm ioctl: remove unnecessary check when using dm_get_mdptr()
dm ioctl: assert _hash_lock is held in __hash_remove
dm cache: add cond_resched() to various workqueue loops
dm thin: add cond_resched() to various workqueue loops
dm: add cond_resched() to dm_wq_requeue_work()
dm: add cond_resched() to dm_wq_work()
dm sysfs: make kobj_type structure constant
dm: update targets using system workqueues to use a local workqueue
dm: remove flush_scheduled_work() during local_exit()
dm clone: prefer kvmalloc_array()
dm: declare variables static when sensible
dm: fix suspect indent whitespace
dm ioctl: prefer strscpy() instead of strlcpy()
dm: avoid void function return statements
dm integrity: change macros min/max() -> min_t/max_t where appropriate
dm: fix use of sizeof() macro
dm: avoid 'do {} while(0)' loop in single statement macros
dm log: avoid multiple line dereference
dm log: avoid trailing semicolon in macro
...
'GPL-2.0-only' is used instead of 'GPL-2.0' because SPDX has
deprecated its use.
Suggested-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
This patch removes the temporary scaffolding now that the comletion
function signature has been converted.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds temporary scaffolding so that the Crypto API
completion function can take a void * instead of crypto_async_request.
Once affected users have been converted this can be removed.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Use strchr() instead of strpbrk() when there is only 1 element in the set
of characters to look for.
This potentially saves a few cycles, but gcc does already account for
optimizing this pattern thanks to it's fold_builtin_strpbrk().
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
The device mapper dm-crypt target is using scnprintf("%02x", cc->key[i]) to
report the current key to userspace. However, this is not a constant-time
operation and it may leak information about the key via timing, via cache
access patterns or via the branch predictor.
Change dm-crypt's key printing to use "%c" instead of "%02x". Also
introduce hex2asc() that carefully avoids any branching or memory
accesses when converting a number in the range 0 ... 15 to an ascii
character.
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
This series consists of the usual driver updates (qla2xxx, pm8001,
libsas, smartpqi, scsi_debug, lpfc, iscsi, mpi3mr) plus minor updates
and bug fixes. The high blast radius core update is the removal of
write same, which affects block and several non-SCSI devices. The
other big change, which is more local, is the removal of the SCSI
pointer.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This series consists of the usual driver updates (qla2xxx, pm8001,
libsas, smartpqi, scsi_debug, lpfc, iscsi, mpi3mr) plus minor updates
and bug fixes.
The high blast radius core update is the removal of write same, which
affects block and several non-SCSI devices. The other big change,
which is more local, is the removal of the SCSI pointer"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (281 commits)
scsi: scsi_ioctl: Drop needless assignment in sg_io()
scsi: bsg: Drop needless assignment in scsi_bsg_sg_io_fn()
scsi: lpfc: Copyright updates for 14.2.0.0 patches
scsi: lpfc: Update lpfc version to 14.2.0.0
scsi: lpfc: SLI path split: Refactor BSG paths
scsi: lpfc: SLI path split: Refactor Abort paths
scsi: lpfc: SLI path split: Refactor SCSI paths
scsi: lpfc: SLI path split: Refactor CT paths
scsi: lpfc: SLI path split: Refactor misc ELS paths
scsi: lpfc: SLI path split: Refactor VMID paths
scsi: lpfc: SLI path split: Refactor FDISC paths
scsi: lpfc: SLI path split: Refactor LS_RJT paths
scsi: lpfc: SLI path split: Refactor LS_ACC paths
scsi: lpfc: SLI path split: Refactor the RSCN/SCR/RDF/EDC/FARPR paths
scsi: lpfc: SLI path split: Refactor PLOGI/PRLI/ADISC/LOGO paths
scsi: lpfc: SLI path split: Refactor base ELS paths and the FLOGI path
scsi: lpfc: SLI path split: Introduce lpfc_prep_wqe
scsi: lpfc: SLI path split: Refactor fast and slow paths to native SLI4
scsi: lpfc: SLI path split: Refactor lpfc_iocbq
scsi: lpfc: Use kcalloc()
...
accounting with focus on fixing wildly inaccurate IO stats for
dm-crypt (and other DM targets that defer bio submission in their
own workqueues). End result is proper IO accounting, made possible
by targets being updated to use the new dm_submit_bio_remap()
interface.
- Add hipri bio polling support (REQ_POLLED) to bio-based DM.
- Reduce dm_io and dm_target_io structs so that a single dm_io (which
contains dm_target_io and first clone bio) weighs in at 256 bytes.
For reference the bio struct is 128 bytes.
- Various other small cleanups, fixes or improvements in DM core and
targets.
- Update MAINTAINERS with my kernel.org email address to allow
distinction between my "upstream" and "Red" Hats.
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Merge tag 'for-5.18/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- Significant refactoring and fixing of how DM core does bio-based IO
accounting with focus on fixing wildly inaccurate IO stats for
dm-crypt (and other DM targets that defer bio submission in their own
workqueues). End result is proper IO accounting, made possible by
targets being updated to use the new dm_submit_bio_remap() interface.
- Add hipri bio polling support (REQ_POLLED) to bio-based DM.
- Reduce dm_io and dm_target_io structs so that a single dm_io (which
contains dm_target_io and first clone bio) weighs in at 256 bytes.
For reference the bio struct is 128 bytes.
- Various other small cleanups, fixes or improvements in DM core and
targets.
- Update MAINTAINERS with my kernel.org email address to allow
distinction between my "upstream" and "Red" Hats.
* tag 'for-5.18/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (46 commits)
dm: consolidate spinlocks in dm_io struct
dm: reduce size of dm_io and dm_target_io structs
dm: switch dm_target_io booleans over to proper flags
dm: switch dm_io booleans over to proper flags
dm: update email address in MAINTAINERS
dm: return void from __send_empty_flush
dm: factor out dm_io_complete
dm cache: use dm_submit_bio_remap
dm: simplify dm_sumbit_bio_remap interface
dm thin: use dm_submit_bio_remap
dm: add WARN_ON_ONCE to dm_submit_bio_remap
dm: support bio polling
block: add ->poll_bio to block_device_operations
dm mpath: use DMINFO instead of printk with KERN_INFO
dm: stop using bdevname
dm-zoned: remove the ->name field in struct dmz_dev
dm: remove unnecessary local variables in __bind
dm: requeue IO if mapping table not yet available
dm io: remove stale comment block for dm_io()
dm thin metadata: remove unused dm_thin_remove_block and __remove
...
Remove the from_wq argument from dm_sumbit_bio_remap(). Eliminates the
need for dm_sumbit_bio_remap() callers to know whether they are
calling for a workqueue or from the original dm_submit_bio().
Add map_task to dm_io struct, record the map_task in alloc_io and
clear it after all target ->map() calls have completed. Update
dm_sumbit_bio_remap to check if 'current' matches io->map_task rather
than rely on passed 'from_rq' argument.
This change really simplifies the chore of porting each DM target to
using dm_sumbit_bio_remap() because there is no longer the risk of
programming error by not completely knowing all the different contexts
a particular method that calls dm_sumbit_bio_remap() might be used in.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use the %pg format specifier to save on stack consuption and code size.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20220304180105.409765-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are no more end-users of REQ_OP_WRITE_SAME left, so we can start
deleting it.
Link: https://lore.kernel.org/r/20220209082828.2629273-7-hch@lst.de
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Explicitly convert unsigned int in the right of the conditional
expression to int to match the left side operand and the return type,
fixing the following compiler warning:
drivers/md/dm-crypt.c:2593:43: warning: signed and unsigned
type in conditional expression [-Wsign-compare]
Fixes: c538f6ec9f ("dm crypt: add ability to use keys from the kernel key retention service")
Signed-off-by: Aashish Sharma <shraash@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Care was taken to support kcryptd_io_read being called from crypt_map
or workqueue. Use of an intermediate CRYPT_MAP_READ_GFP gfp_t
(defined as GFP_NOWAIT) should protect from maintenance burden if that
flag were to change for some reason.
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pass a block_device to bio_clone_fast and __bio_clone_fast and give
the functions more suitable names.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20220202160109.108149-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pass the block_device and operation that we plan to use this bio for to
bio_alloc_bioset to optimize the assigment. NULL/0 can be passed, both
for the passthrough case on a raw request_queue and to temporarily avoid
refactoring some nasty code.
Also move the gfp_mask argument after the nr_vecs argument for a much
more logical calling convention matching what most of the kernel does.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220124091107.642561-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just open code it next to the bio allocations, which saves a few lines
of code, prepares for future changes and allows to remove the duplicate
bi_opf assignment for the bio_clone_fast case in kcryptd_io_read.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220124091107.642561-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Remove handling of NULL returns from sleeping bio_alloc calls given that
those can't fail.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220124091107.642561-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
subsystem. Also enhance both the integrity and crypt targets to emit
events to via dm-audit.
- Various other simple code improvements and cleanups.
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Merge tag 'for-5.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- Add DM core support for emitting audit events through the audit
subsystem. Also enhance both the integrity and crypt targets to emit
events to via dm-audit.
- Various other simple code improvements and cleanups.
* tag 'for-5.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm table: log table creation error code
dm: make workqueue names device-specific
dm writecache: Make use of the helper macro kthread_run()
dm crypt: Make use of the helper macro kthread_run()
dm verity: use bvec_kmap_local in verity_for_bv_block
dm log writes: use memcpy_from_bvec in log_writes_map
dm integrity: use bvec_kmap_local in __journal_read_write
dm integrity: use bvec_kmap_local in integrity_metadata
dm: add add_disk() error handling
dm: Remove redundant flush_workqueue() calls
dm crypt: log aead integrity violations to audit subsystem
dm integrity: log audit events for dm-integrity target
dm: introduce audit event module for device mapper
Replace kthread_create/wake_up_process() with kthread_run()
to simplify the code.
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Since dm-crypt target can be stacked on dm-integrity targets to
provide authenticated encryption, integrity violations are recognized
here during aead computation. We use the dm-audit submodule to
signal those events to user space, too.
The construction and destruction of crypt device mappings are also
logged as audit events.
Signed-off-by: Michael Weiß <michael.weiss@aisec.fraunhofer.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Split the integrity/metadata handling definitions out into a new header.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-17-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
On systems with many cores using dm-crypt, heavy spinlock contention in
percpu_counter_compare() can be observed when the page allocation limit
for a given device is reached or close to be reached. This is due
to percpu_counter_compare() taking a spinlock to compute an exact
result on potentially many CPUs at the same time.
Switch to non-exact comparison of allocated and allowed pages by using
the value returned by percpu_counter_read_positive() to avoid taking
the percpu_counter spinlock.
This may over/under estimate the actual number of allocated pages by at
most (batch-1) * num_online_cpus().
Currently, batch is bounded by 32. The system on which this issue was
first observed has 256 CPUs and 512GB of RAM. With a 4k page size, this
change may over/under estimate by 31MB. With ~10G (2%) allowed dm-crypt
allocations, this seems an acceptable error. Certainly preferred over
running into the spinlock contention.
This behavior was reproduced on an EC2 c5.24xlarge instance with 96 CPUs
and 192GB RAM as follows, but can be provoked on systems with less CPUs
as well.
* Disable swap
* Tune vm settings to promote regular writeback
$ echo 50 > /proc/sys/vm/dirty_expire_centisecs
$ echo 25 > /proc/sys/vm/dirty_writeback_centisecs
$ echo $((128 * 1024 * 1024)) > /proc/sys/vm/dirty_background_bytes
* Create 8 dmcrypt devices based on files on a tmpfs
* Create and mount an ext4 filesystem on each crypt devices
* Run stress-ng --hdd 8 within one of above filesystems
Total %system usage collected from sysstat goes to ~35%. Write throughput
on the underlying loop device is ~2GB/s. perf profiling an individual
kworker kcryptd thread shows the following profile, indicating spinlock
contention in percpu_counter_compare():
99.98% 0.00% kworker/u193:46 [kernel.kallsyms] [k] ret_from_fork
|
--ret_from_fork
kthread
worker_thread
|
--99.92%--process_one_work
|
|--80.52%--kcryptd_crypt
| |
| |--62.58%--mempool_alloc
| | |
| | --62.24%--crypt_page_alloc
| | |
| | --61.51%--__percpu_counter_compare
| | |
| | --61.34%--__percpu_counter_sum
| | |
| | |--58.68%--_raw_spin_lock_irqsave
| | | |
| | | --58.30%--native_queued_spin_lock_slowpath
| | |
| | --0.69%--cpumask_next
| | |
| | --0.51%--_find_next_bit
| |
| |--10.61%--crypt_convert
| | |
| | |--6.05%--xts_crypt
...
After applying this patch and running the same test, %system usage is
lowered to ~7% and write throughput on the loop device increases
to ~2.7GB/s. perf report shows mempool_alloc() as ~8% rather than ~62%
in the profile and not hitting the percpu_counter() spinlock anymore.
|--8.15%--mempool_alloc
| |
| |--3.93%--crypt_page_alloc
| | |
| | --3.75%--__alloc_pages
| | |
| | --3.62%--get_page_from_freelist
| | |
| | --3.22%--rmqueue_bulk
| | |
| | --2.59%--_raw_spin_lock
| | |
| | --2.57%--native_queued_spin_lock_slowpath
| |
| --3.05%--_raw_spin_lock_irqsave
| |
| --2.49%--native_queued_spin_lock_slowpath
Suggested-by: DJ Gregor <dj@corelight.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Arne Welzel <arne.welzel@corelight.com>
Fixes: 5059353df8 ("dm crypt: limit the number of allocated pages")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
For device mapper targets to take advantage of IMA's measurement
capabilities, the status functions for the individual targets need to be
updated to handle the status_type_t case for value STATUSTYPE_IMA.
Update status functions for the following target types, to log their
respective attributes to be measured using IMA.
01. cache
02. crypt
03. integrity
04. linear
05. mirror
06. multipath
07. raid
08. snapshot
09. striped
10. verity
For rest of the targets, handle the STATUSTYPE_IMA case by setting the
measurement buffer to NULL.
For IMA to measure the data on a given system, the IMA policy on the
system needs to be updated to have the following line, and the system
needs to be restarted for the measurements to take effect.
/etc/ima/ima-policy
measure func=CRITICAL_DATA label=device-mapper template=ima-buf
The measurements will be reflected in the IMA logs, which are located at:
/sys/kernel/security/integrity/ima/ascii_runtime_measurements
/sys/kernel/security/integrity/ima/binary_runtime_measurements
These IMA logs can later be consumed by various attestation clients
running on the system, and send them to external services for attesting
the system.
The DM target data measured by IMA subsystem can alternatively
be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with
DM_TABLE_STATUS_CMD.
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Zone append BIOs (REQ_OP_ZONE_APPEND) always specify the start sector
of the zone to be written instead of the actual sector location to
write. The write location is determined by the device and returned to
the host upon completion of the operation. This interface, while simple
and efficient for writing into sequential zones of a zoned block
device, is incompatible with the use of sector values to calculate a
cypher block IV. All data written in a zone end up using the same IV
values corresponding to the first sectors of the zone, but read
operation will specify any sector within the zone resulting in an IV
mismatch between encryption and decryption.
To solve this problem, report to DM core that zone append operations are
not supported. This result in the zone append operations being emulated
using regular write operations.
Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
To simplify the implementation of the report_zones operation of a zoned
target, introduce the function dm_report_zones() to set a target
mapping start sector in struct dm_report_zones_args and call
blkdev_report_zones(). This new function is exported and the report
zones callback function dm_report_zones_cb() is not.
dm-linear, dm-flakey and dm-crypt are modified to use dm_report_zones().
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been
horribly confusingly misnamed. Rename it to BIO_MAX_VECS to stop
confusing users of the bio API.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The system would deadlock when swapping to a dm-crypt device. The reason
is that for each incoming write bio, dm-crypt allocates memory that holds
encrypted data. These excessive allocations exhaust all the memory and the
result is either deadlock or OOM trigger.
This patch limits the number of in-flight swap bios, so that the memory
consumed by dm-crypt is limited. The limit is enforced if the target set
the "limit_swap_bios" variable and if the bio has REQ_SWAP set.
Non-swap bios are not affected becuase taking the semaphore would cause
performance degradation.
This is similar to request-based drivers - they will also block when the
number of requests is over the limit.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Allow removal of CONFIG_BLK_DEV_ZONED conditionals in target_type
definition of various targets.
Suggested-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 27f5411a71 ("dm crypt: support using encrypted keys") extended
dm-crypt to allow use of "encrypted" keys along with "user" and "logon".
Along the same lines, teach dm-crypt to support "trusted" keys as well.
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
IS_ENABLED(CONFIG_ENCRYPTED_KEYS) is true whether the option is built-in
or a module, so use it instead of #if defined checking for each
separately.
The other #if was to avoid a static function defined, but unused
warning. As we now always build the callsite when the function
is defined, we can remove that first #if guard.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In commit d68b29584c ("dm crypt: use GFP_ATOMIC when allocating
crypto requests from softirq") code was incorrectly copy and pasted
from crypt_alloc_req_skcipher()'s crypto request allocation code to
crypt_alloc_req_aead(). It is OK from runtime perspective as both
simple encryption request pointer and AEAD request pointer are part of
a union, but may confuse code reviewers.
Fixes: d68b29584c ("dm crypt: use GFP_ATOMIC when allocating crypto requests from softirq")
Cc: stable@vger.kernel.org # v5.9+
Reported-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Sometimes, when dm-crypt executes decryption in a tasklet, we may get
"BUG: KASAN: use-after-free in tasklet_action_common.constprop..."
with a kasan-enabled kernel.
When the decryption fully completes in the tasklet, dm-crypt will call
bio_endio(), which in turn will call clone_endio() from dm.c core code. That
function frees the resources associated with the bio, including per bio private
structures. For dm-crypt it will free the current struct dm_crypt_io, which
contains our tasklet object, causing use-after-free, when the tasklet is being
dequeued by the kernel.
To avoid this, do not call bio_endio() from the current tasklet context, but
delay its execution to the dm-crypt IO workqueue.
Fixes: 39d42fa96b ("dm crypt: add flags to optionally bypass kcryptd workqueues")
Cc: <stable@vger.kernel.org> # v5.9+
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Yangtao Li