Add the const qualifier to all the ctl_tables in the tree except for
watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls,
loadpin_sysctl_table and the ones calling register_net_sysctl (./net,
drivers/inifiniband dirs). These are special cases as they use a
registration function with a non-const qualified ctl_table argument or
modify the arrays before passing them on to the registration function.
Constifying ctl_table structs will prevent the modification of
proc_handler function pointers as the arrays would reside in .rodata.
This is made possible after commit 78eb4ea25c ("sysctl: treewide:
constify the ctl_table argument of proc_handlers") constified all the
proc_handlers.
Created this by running an spatch followed by a sed command:
Spatch:
virtual patch
@
depends on !(file in "net")
disable optional_qualifier
@
identifier table_name != {
watchdog_hardlockup_sysctl,
iwcm_ctl_table,
ucma_ctl_table,
memory_allocation_profiling_sysctls,
loadpin_sysctl_table
};
@@
+ const
struct ctl_table table_name [] = { ... };
sed:
sed --in-place \
-e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \
kernel/utsname_sysctl.c
Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> # for kernel/trace/
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> # SCSI
Reviewed-by: Darrick J. Wong <djwong@kernel.org> # xfs
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Joel Granados <joel.granados@kernel.org>
- Reorganize the architecture-optimized CRC32 and CRC-T10DIF code to be
directly accessible via the library API, instead of requiring the
crypto API. This is much simpler and more efficient.
- Convert some users such as ext4 to use the CRC32 library API instead
of the crypto API. More conversions like this will come later.
- Add a KUnit test that tests and benchmarks multiple CRC variants.
Remove older, less-comprehensive tests that are made redundant by
this.
- Add an entry to MAINTAINERS for the kernel's CRC library code. I'm
volunteering to maintain it. I have additional cleanups and
optimizations planned for future cycles.
These patches have been in linux-next since -rc1.
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Merge tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux
Pull CRC updates from Eric Biggers:
- Reorganize the architecture-optimized CRC32 and CRC-T10DIF code to be
directly accessible via the library API, instead of requiring the
crypto API. This is much simpler and more efficient.
- Convert some users such as ext4 to use the CRC32 library API instead
of the crypto API. More conversions like this will come later.
- Add a KUnit test that tests and benchmarks multiple CRC variants.
Remove older, less-comprehensive tests that are made redundant by
this.
- Add an entry to MAINTAINERS for the kernel's CRC library code. I'm
volunteering to maintain it. I have additional cleanups and
optimizations planned for future cycles.
* tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: (31 commits)
MAINTAINERS: add entry for CRC library
powerpc/crc: delete obsolete crc-vpmsum_test.c
lib/crc32test: delete obsolete crc32test.c
lib/crc16_kunit: delete obsolete crc16_kunit.c
lib/crc_kunit.c: add KUnit test suite for CRC library functions
powerpc/crc-t10dif: expose CRC-T10DIF function through lib
arm64/crc-t10dif: expose CRC-T10DIF function through lib
arm/crc-t10dif: expose CRC-T10DIF function through lib
x86/crc-t10dif: expose CRC-T10DIF function through lib
crypto: crct10dif - expose arch-optimized lib function
lib/crc-t10dif: add support for arch overrides
lib/crc-t10dif: stop wrapping the crypto API
scsi: target: iscsi: switch to using the crc32c library
f2fs: switch to using the crc32 library
jbd2: switch to using the crc32c library
ext4: switch to using the crc32c library
lib/crc32: make crc32c() go directly to lib
bcachefs: Explicitly select CRYPTO from BCACHEFS_FS
x86/crc32: expose CRC32 functions through lib
x86/crc32: update prototype for crc32_pclmul_le_16()
...
1) Per-CPU kthreads must stay affine to a single CPU and never execute
relevant code on any other CPU. This is currently handled by smpboot
code which takes care of CPU-hotplug operations. Affinity here is
a correctness constraint.
2) Some kthreads _have_ to be affine to a specific set of CPUs and can't
run anywhere else. The affinity is set through kthread_bind_mask()
and the subsystem takes care by itself to handle CPU-hotplug
operations. Affinity here is assumed to be a correctness constraint.
3) Per-node kthreads _prefer_ to be affine to a specific NUMA node. This
is not a correctness constraint but merely a preference in terms of
memory locality. kswapd and kcompactd both fall into this category.
The affinity is set manually like for any other task and CPU-hotplug
is supposed to be handled by the relevant subsystem so that the task
is properly reaffined whenever a given CPU from the node comes up.
Also care should be taken so that the node affinity doesn't cross
isolated (nohz_full) cpumask boundaries.
4) Similar to the previous point except kthreads have a _preferred_
affinity different than a node. Both RCU boost kthreads and RCU
exp kworkers fall into this category as they refer to "RCU nodes"
from a distinctly distributed tree.
Currently the preferred affinity patterns (3 and 4) have at least 4
identified users, with more or less success when it comes to handle
CPU-hotplug operations and CPU isolation. Each of which do it in its own
ad-hoc way.
This is an infrastructure proposal to handle this with the following API
changes:
_ kthread_create_on_node() automatically affines the created kthread to
its target node unless it has been set as per-cpu or bound with
kthread_bind[_mask]() before the first wake-up.
- kthread_affine_preferred() is a new function that can be called right
after kthread_create_on_node() to specify a preferred affinity
different than the specified node.
When the preferred affinity can't be applied because the possible
targets are offline or isolated (nohz_full), the kthread is affine
to the housekeeping CPUs (which means to all online CPUs most of the
time or only the non-nohz_full CPUs when nohz_full= is set).
kswapd, kcompactd, RCU boost kthreads and RCU exp kworkers have been
converted, along with a few old drivers.
Summary of the changes:
* Consolidate a bunch of ad-hoc implementations of kthread_run_on_cpu()
* Introduce task_cpu_fallback_mask() that defines the default last
resort affinity of a task to become nohz_full aware
* Add some correctness check to ensure kthread_bind() is always called
before the first kthread wake up.
* Default affine kthread to its preferred node.
* Convert kswapd / kcompactd and remove their halfway working ad-hoc
affinity implementation
* Implement kthreads preferred affinity
* Unify kthread worker and kthread API's style
* Convert RCU kthreads to the new API and remove the ad-hoc affinity
implementation.
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Merge tag 'kthread-for-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks
Pull kthread updates from Frederic Weisbecker:
"Kthreads affinity follow either of 4 existing different patterns:
1) Per-CPU kthreads must stay affine to a single CPU and never
execute relevant code on any other CPU. This is currently handled
by smpboot code which takes care of CPU-hotplug operations.
Affinity here is a correctness constraint.
2) Some kthreads _have_ to be affine to a specific set of CPUs and
can't run anywhere else. The affinity is set through
kthread_bind_mask() and the subsystem takes care by itself to
handle CPU-hotplug operations. Affinity here is assumed to be a
correctness constraint.
3) Per-node kthreads _prefer_ to be affine to a specific NUMA node.
This is not a correctness constraint but merely a preference in
terms of memory locality. kswapd and kcompactd both fall into this
category. The affinity is set manually like for any other task and
CPU-hotplug is supposed to be handled by the relevant subsystem so
that the task is properly reaffined whenever a given CPU from the
node comes up. Also care should be taken so that the node affinity
doesn't cross isolated (nohz_full) cpumask boundaries.
4) Similar to the previous point except kthreads have a _preferred_
affinity different than a node. Both RCU boost kthreads and RCU
exp kworkers fall into this category as they refer to "RCU nodes"
from a distinctly distributed tree.
Currently the preferred affinity patterns (3 and 4) have at least 4
identified users, with more or less success when it comes to handle
CPU-hotplug operations and CPU isolation. Each of which do it in its
own ad-hoc way.
This is an infrastructure proposal to handle this with the following
API changes:
- kthread_create_on_node() automatically affines the created kthread
to its target node unless it has been set as per-cpu or bound with
kthread_bind[_mask]() before the first wake-up.
- kthread_affine_preferred() is a new function that can be called
right after kthread_create_on_node() to specify a preferred
affinity different than the specified node.
When the preferred affinity can't be applied because the possible
targets are offline or isolated (nohz_full), the kthread is affine to
the housekeeping CPUs (which means to all online CPUs most of the time
or only the non-nohz_full CPUs when nohz_full= is set).
kswapd, kcompactd, RCU boost kthreads and RCU exp kworkers have been
converted, along with a few old drivers.
Summary of the changes:
- Consolidate a bunch of ad-hoc implementations of
kthread_run_on_cpu()
- Introduce task_cpu_fallback_mask() that defines the default last
resort affinity of a task to become nohz_full aware
- Add some correctness check to ensure kthread_bind() is always
called before the first kthread wake up.
- Default affine kthread to its preferred node.
- Convert kswapd / kcompactd and remove their halfway working ad-hoc
affinity implementation
- Implement kthreads preferred affinity
- Unify kthread worker and kthread API's style
- Convert RCU kthreads to the new API and remove the ad-hoc affinity
implementation"
* tag 'kthread-for-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks:
kthread: modify kernel-doc function name to match code
rcu: Use kthread preferred affinity for RCU exp kworkers
treewide: Introduce kthread_run_worker[_on_cpu]()
kthread: Unify kthread_create_on_cpu() and kthread_create_worker_on_cpu() automatic format
rcu: Use kthread preferred affinity for RCU boost
kthread: Implement preferred affinity
mm: Create/affine kswapd to its preferred node
mm: Create/affine kcompactd to its preferred node
kthread: Default affine kthread to its preferred NUMA node
kthread: Make sure kthread hasn't started while binding it
sched,arm64: Handle CPU isolation on last resort fallback rq selection
arm64: Exclude nohz_full CPUs from 32bits el0 support
lib: test_objpool: Use kthread_run_on_cpu()
kallsyms: Use kthread_run_on_cpu()
soc/qman: test: Use kthread_run_on_cpu()
arm/bL_switcher: Use kthread_run_on_cpu()
key_being_used_for[] is an unused array of textual names for
the elements of the enum key_being_used_for. It was added in 2015 by
commit 99db443506 ("PKCS#7: Appropriately restrict authenticated
attributes and content type")
Remove it.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In skcipher_walk_done(), instead of calling crypto_yield() which
requires a translation between flags, just call cond_resched() directly.
This has the same effect.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The helper functions like crypto_skcipher_blocksize() take in a pointer
to a tfm object, but they actually return properties of the algorithm.
As the Linux kernel is compiled with -fno-strict-aliasing, the compiler
has to assume that the writes to struct skcipher_walk could clobber the
tfm's pointer to its algorithm. Thus it gets repeatedly reloaded in the
generated code. Therefore, replace the use of these helper functions
with staightforward accesses to the struct fields.
Note that while *users* of the skcipher and aead APIs are supposed to
use the helper functions, this particular code is part of the API
*implementation* in crypto/skcipher.c, which already accesses the
algorithm struct directly in many cases. So there is no reason to
prefer the helper functions here.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
- Initialize SKCIPHER_WALK_SLEEP in a consistent way, and check for
atomic=true at the same time as CRYPTO_TFM_REQ_MAY_SLEEP. Technically
atomic=true only needs to apply after the first step, but it is very
rarely used. We should optimize for the common case. So, check
'atomic' alongside CRYPTO_TFM_REQ_MAY_SLEEP. This is more efficient.
- Initialize flags other than SKCIPHER_WALK_SLEEP to 0 rather than
preserving them. No caller actually initializes the flags, which
makes it impossible to use their original values for anything.
Indeed, that does not happen and all meaningful flags get overridden
anyway. It may have been thought that just clearing one flag would be
faster than clearing all flags, but that's not the case as the former
is a read-write operation whereas the latter is just a write.
- Move the explicit clearing of SKCIPHER_WALK_SLOW, SKCIPHER_WALK_COPY,
and SKCIPHER_WALK_DIFF into skcipher_walk_done(), since it is now
only needed on non-first steps.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Fold skcipher_walk_skcipher() into skcipher_walk_virt() which is its
only remaining caller. No change in behavior.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In skcipher_walk_done(), remove the check for SKCIPHER_WALK_SLOW because
it is always true. All other flags (and lack thereof) were checked
earlier in the function, leaving SKCIPHER_WALK_SLOW as the only
remaining possibility.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In the case where skcipher_walk_next() allocates a bounce page, that
page by definition has size PAGE_SIZE. The number of bytes to copy 'n'
is guaranteed to fit in it, since earlier in the function it was clamped
to be at most a page. Therefore remove the unnecessary logic that tried
to clamp 'n' again to fit in the bounce page.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In the slow path of skcipher_walk where it uses a slab bounce buffer for
the data and/or IV, do not bother to avoid crossing a page boundary in
the part(s) of this buffer that are used, and do not bother to allocate
extra space in the buffer for that purpose. The buffer is accessed only
by virtual address, so pages are irrelevant for it.
This logic may have been present due to the physical address support in
skcipher_walk, but that has now been removed. Or it may have been
present to be consistent with the fast path that currently does not hand
back addresses that span pages, but that behavior is a side effect of
the pages being "mapped" one by one and is not actually a requirement.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
skcipher_walk_done() has an unusual calling convention, and some of its
local variables have unclear names. Document it and rename variables to
make it a bit clearer what is going on. No change in behavior.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove hard-coded strings by using the str_yes_no() and str_no_yes()
helpers. Remove unnecessary curly braces.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
kthread_create() creates a kthread without running it yet. kthread_run()
creates a kthread and runs it.
On the other hand, kthread_create_worker() creates a kthread worker and
runs it.
This difference in behaviours is confusing. Also there is no way to
create a kthread worker and affine it using kthread_bind_mask() or
kthread_affine_preferred() before starting it.
Consolidate the behaviours and introduce kthread_run_worker[_on_cpu]()
that behaves just like kthread_run(). kthread_create_worker[_on_cpu]()
will now only create a kthread worker without starting it.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Due to the removal of the Niagara2 SPU driver, crypto_hash_walk_first(),
crypto_hash_walk_done(), crypto_hash_walk_last(), and struct
crypto_hash_walk are now only used in crypto/ahash.c. Therefore, make
them all private to crypto/ahash.c. I.e. un-export the two functions
that were exported, make the functions static, and move the struct
definition to the .c file. As part of this, move the functions to
earlier in the file to avoid needing to add forward declarations.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The keywrap (kw) algorithm has no in-tree user. It has never had an
in-tree user, and the patch that added it provided no justification for
its inclusion. Even use of it via AF_ALG is impossible, as it uses a
weird calling convention where part of the ciphertext is returned via
the IV buffer, which is not returned to userspace in AF_ALG.
It's also unclear whether any new code in the kernel that does key
wrapping would actually use this algorithm. It is controversial in the
cryptographic community due to having no clearly stated security goal,
no security proof, poor performance, and only a 64-bit auth tag. Later
work (https://eprint.iacr.org/2006/221) suggested that the goal is
deterministic authenticated encryption. But there are now more modern
algorithms for this, and this is not the same as key wrapping, for which
a regular AEAD such as AES-GCM usually can be (and is) used instead.
Therefore, remove this unused code.
There were several special cases for this algorithm in the self-tests,
due to its weird calling convention. Remove those too.
Cc: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove the vmac64 template, as it has no known users. It also continues
to have longstanding bugs such as alignment violations (see
https://lore.kernel.org/r/20241226134847.6690-1-evepolonium@gmail.com/).
This code was added in 2009 by commit f1939f7c56 ("crypto: vmac - New
hash algorithm for intel_txt support"). Based on the mention of
intel_txt support in the commit title, it seems it was added as a
prerequisite for the contemporaneous patch
"intel_txt: add s3 userspace memory integrity verification"
(https://lore.kernel.org/r/4ABF2B50.6070106@intel.com/). In the design
proposed by that patch, when an Intel Trusted Execution Technology (TXT)
enabled system resumed from suspend, the "tboot" trusted executable
launched the Linux kernel without verifying userspace memory, and then
the Linux kernel used VMAC to verify userspace memory.
However, that patch was never merged, as reviewers had objected to the
design. It was later reworked into commit 4bd96a7a81 ("x86, tboot:
Add support for S3 memory integrity protection") which made tboot verify
the memory instead. Thus the VMAC support in Linux was never used.
No in-tree user has appeared since then, other than potentially the
usual components that allow specifying arbitrary hash algorithms by
name, namely AF_ALG and dm-integrity. However there are no indications
that VMAC is being used with these components. Debian Code Search and
web searches for "vmac64" (the actual algorithm name) do not return any
results other than the kernel itself, suggesting that it does not appear
in any other code or documentation. Explicitly grepping the source code
of the usual suspects (libell, iwd, cryptsetup) finds no matches either.
Before 2018, the vmac code was also completely broken due to using a
hardcoded nonce and the wrong endianness for the MAC. It was then fixed
by commit ed331adab3 ("crypto: vmac - add nonced version with big
endian digest") and commit 0917b87312 ("crypto: vmac - remove insecure
version with hardcoded nonce"). These were intentionally breaking
changes that changed all the computed MAC values as well as the
algorithm name ("vmac" to "vmac64"). No complaints were ever received
about these breaking changes, strongly suggesting the absence of users.
The reason I had put some effort into fixing this code in 2018 is
because it was used by an out-of-tree driver. But if it is still needed
in that particular out-of-tree driver, the code can be carried in that
driver instead. There is no need to carry it upstream.
Cc: Atharva Tiwari <evepolonium@gmail.com>
Cc: Shane Wang <shane.wang@intel.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove hard-coded strings by using the str_enabled_disabled() helper
function.
Use pr_info() instead of printk(KERN_INFO) to silence a checkpatch
warning.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since this code is zero-initializing the algorithm struct, the
assignment of 0 to cra_alignmask is redundant. Remove it to reduce the
number of matches that are found when grepping for cra_alignmask.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Struct fields are zero by default, so these lines of code have no
effect. Remove them to reduce the number of matches that are found when
grepping for cra_alignmask.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Instead of specifying a nonzero alignmask, use the unaligned access
helpers. This eliminates unnecessary alignment operations on most CPUs,
which can handle unaligned accesses efficiently, and brings us a step
closer to eventually removing support for the alignmask field.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Instead of specifying a nonzero alignmask, use the unaligned access
helpers. This eliminates unnecessary alignment operations on most CPUs,
which can handle unaligned accesses efficiently, and brings us a step
closer to eventually removing support for the alignmask field.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Instead of specifying a nonzero alignmask, use the unaligned access
helpers. This eliminates unnecessary alignment operations on most CPUs,
which can handle unaligned accesses efficiently, and brings us a step
closer to eventually removing support for the alignmask field.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Instead of specifying a nonzero alignmask, use the unaligned access
helpers. This eliminates unnecessary alignment operations on most CPUs,
which can handle unaligned accesses efficiently, and brings us a step
closer to eventually removing support for the alignmask field.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Instead of specifying a nonzero alignmask, use the unaligned access
helpers. This eliminates unnecessary alignment operations on most CPUs,
which can handle unaligned accesses efficiently, and brings us a step
closer to eventually removing support for the alignmask field.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since the physical address support in skcipher_walk is not used anymore,
remove all the code associated with it. This includes:
- The skcipher_walk_async() and skcipher_walk_complete() functions;
- The SKCIPHER_WALK_PHYS flag and everything conditional on it;
- The buffers, phys, and virt.page fields in struct skcipher_walk;
- struct skcipher_walk_buffer.
As a result, skcipher_walk now just supports virtual addresses.
Physical address support in skcipher_walk is unneeded because drivers
that need physical addresses just use the scatterlists directly.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As sig is now a standalone type, it no longer needs to have a wide
mask that includes akcipher.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
There is no need to hold the crypto mutex when scheduling a self-
test. In fact prior to the patch introducing asynchronous testing,
this was done outside of the locked area.
Move the crypto_schedule_test call back out of the locked area.
Also move crypto_remove_final to the else branch under the schedule-
test call as the list of algorithms to be removed is non-empty only
when the test larval is NULL (i.e., testing is disabled).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
During the boot process self-tests are postponed so that all
algorithms are registered when the test starts. In the event
that algorithms are still being registered during these tests,
which can occur either because the algorithm is registered at
late_initcall, or because a self-test itself triggers the creation
of an instance, some self-tests may never start at all.
Fix this by setting the flag at the start of crypto_start_tests.
Note that this race is theoretical and has never been observed
in practice.
Fixes: adad556efc ("crypto: api - Fix built-in testing dependency failures")
Signed-off-by: Herbert Xu <herbert.xu@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As virtual addresses in general may not be suitable for DMA, always
perform a copy before using them in an SG list.
Fixes: 1e562deace ("crypto: rsassa-pkcs1 - Migrate to sig_alg backend")
Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now that crc_t10dif_update() may be directly optimized for each
architecture, make the shash driver for crct10dif register a
crct10dif-$arch algorithm that uses it, instead of only
crct10dif-generic which uses crc_t10dif_generic().
The result is that architecture-optimized crct10dif will remain
available through the shash API once the architectures implement
crc_t10dif_arch() instead of the shash API.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20241202012056.209768-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
In preparation for making the CRC-T10DIF library directly optimized for
each architecture, like what has been done for CRC32, get rid of the
weird layering where crc_t10dif_update() calls into the crypto API.
Instead, move crc_t10dif_generic() into the crc-t10dif library module,
and make crc_t10dif_update() just call crc_t10dif_generic().
Acceleration will be reintroduced via crc_t10dif_arch() in the following
patches.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20241202012056.209768-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Instead of registering the crc32-$arch and crc32c-$arch algorithms if
the arch-specific code was built, only register them when that code was
built *and* is not falling back to the base implementation at runtime.
This avoids confusing users like btrfs which checks the shash driver
name to determine whether it is crc32c-generic.
(It would also make sense to change btrfs to test the crc32_optimization
flags itself, so that it doesn't have to use the weird hack of parsing
the driver name. This change still makes sense either way though.)
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20241202010844.144356-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Currently the CRC32 library functions are defined as weak symbols, and
the arm64 and riscv architectures override them.
This method of arch-specific overrides has the limitation that it only
works when both the base and arch code is built-in. Also, it makes the
arch-specific code be silently not used if it is accidentally built with
lib-y instead of obj-y; unfortunately the RISC-V code does this.
This commit reorganizes the code to have explicit *_arch() functions
that are called when they are enabled, similar to how some of the crypto
library code works (e.g. chacha_crypt() calls chacha_crypt_arch()).
Make the existing kconfig choice for the CRC32 implementation also
control whether the arch-optimized implementation (if one is available)
is enabled or not. Make it enabled by default if CRC32 is also enabled.
The result is that arch-optimized CRC32 library functions will be
included automatically when appropriate, but it is now possible to
disable them. They can also now be built as a loadable module if the
CRC32 library functions happen to be used only by loadable modules, in
which case the arch and base CRC32 modules will be automatically loaded
via direct symbol dependency when appropriate.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20241202010844.144356-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Remove the leading underscores from __crc32c_le_base().
This is in preparation for adding crc32c_le_arch() and eventually
renaming __crc32c_le() to crc32c_le().
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20241202010844.144356-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
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Merge tag 'random-6.13-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random
Pull random number generator updates from Jason Donenfeld:
"This contains a single series from Uros to replace uses of
<linux/random.h> with prandom.h or other more specific headers
as needed, in order to avoid a circular header issue.
Uros' goal is to be able to use percpu.h from prandom.h, which
will then allow him to define __percpu in percpu.h rather than
in compiler_types.h"
* tag 'random-6.13-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
prandom: Include <linux/percpu.h> in <linux/prandom.h>
random: Do not include <linux/prandom.h> in <linux/random.h>
netem: Include <linux/prandom.h> in sch_netem.c
lib/test_scanf: Include <linux/prandom.h> instead of <linux/random.h>
lib/test_parman: Include <linux/prandom.h> instead of <linux/random.h>
bpf/tests: Include <linux/prandom.h> instead of <linux/random.h>
lib/rbtree-test: Include <linux/prandom.h> instead of <linux/random.h>
random32: Include <linux/prandom.h> instead of <linux/random.h>
kunit: string-stream-test: Include <linux/prandom.h>
lib/interval_tree_test.c: Include <linux/prandom.h> instead of <linux/random.h>
bpf: Include <linux/prandom.h> instead of <linux/random.h>
scsi: libfcoe: Include <linux/prandom.h> instead of <linux/random.h>
fscrypt: Include <linux/once.h> in fs/crypto/keyring.c
mtd: tests: Include <linux/prandom.h> instead of <linux/random.h>
media: vivid: Include <linux/prandom.h> in vivid-vid-cap.c
drm/lib: Include <linux/prandom.h> instead of <linux/random.h>
drm/i915/selftests: Include <linux/prandom.h> instead of <linux/random.h>
crypto: testmgr: Include <linux/prandom.h> instead of <linux/random.h>
x86/kaslr: Include <linux/prandom.h> instead of <linux/random.h>
API:
- Add sig driver API.
- Remove signing/verification from akcipher API.
- Move crypto_simd_disabled_for_test to lib/crypto.
- Add WARN_ON for return values from driver that indicates memory corruption.
Algorithms:
- Provide crc32-arch and crc32c-arch through Crypto API.
- Optimise crc32c code size on x86.
- Optimise crct10dif on arm/arm64.
- Optimise p10-aes-gcm on powerpc.
- Optimise aegis128 on x86.
- Output full sample from test interface in jitter RNG.
- Retry without padata when it fails in pcrypt.
Drivers:
- Add support for Airoha EN7581 TRNG.
- Add support for STM32MP25x platforms in stm32.
- Enable iproc-r200 RNG driver on BCMBCA.
- Add Broadcom BCM74110 RNG driver.
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Merge tag 'v6.13-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
"API:
- Add sig driver API
- Remove signing/verification from akcipher API
- Move crypto_simd_disabled_for_test to lib/crypto
- Add WARN_ON for return values from driver that indicates memory
corruption
Algorithms:
- Provide crc32-arch and crc32c-arch through Crypto API
- Optimise crc32c code size on x86
- Optimise crct10dif on arm/arm64
- Optimise p10-aes-gcm on powerpc
- Optimise aegis128 on x86
- Output full sample from test interface in jitter RNG
- Retry without padata when it fails in pcrypt
Drivers:
- Add support for Airoha EN7581 TRNG
- Add support for STM32MP25x platforms in stm32
- Enable iproc-r200 RNG driver on BCMBCA
- Add Broadcom BCM74110 RNG driver"
* tag 'v6.13-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (112 commits)
crypto: marvell/cesa - fix uninit value for struct mv_cesa_op_ctx
crypto: cavium - Fix an error handling path in cpt_ucode_load_fw()
crypto: aesni - Move back to module_init
crypto: lib/mpi - Export mpi_set_bit
crypto: aes-gcm-p10 - Use the correct bit to test for P10
hwrng: amd - remove reference to removed PPC_MAPLE config
crypto: arm/crct10dif - Implement plain NEON variant
crypto: arm/crct10dif - Macroify PMULL asm code
crypto: arm/crct10dif - Use existing mov_l macro instead of __adrl
crypto: arm64/crct10dif - Remove remaining 64x64 PMULL fallback code
crypto: arm64/crct10dif - Use faster 16x64 bit polynomial multiply
crypto: arm64/crct10dif - Remove obsolete chunking logic
crypto: bcm - add error check in the ahash_hmac_init function
crypto: caam - add error check to caam_rsa_set_priv_key_form
hwrng: bcm74110 - Add Broadcom BCM74110 RNG driver
dt-bindings: rng: add binding for BCM74110 RNG
padata: Clean up in padata_do_multithreaded()
crypto: inside-secure - Fix the return value of safexcel_xcbcmac_cra_init()
crypto: qat - Fix missing destroy_workqueue in adf_init_aer()
crypto: rsassa-pkcs1 - Reinstate support for legacy protocols
...
Commit 1e562deace ("crypto: rsassa-pkcs1 - Migrate to sig_alg backend")
enforced that rsassa-pkcs1 sign/verify operations specify a hash
algorithm. That is necessary because per RFC 8017 sec 8.2, a hash
algorithm identifier must be prepended to the hash before generating or
verifying the signature ("Full Hash Prefix").
However the commit went too far in that it changed user space behavior:
KEYCTL_PKEY_QUERY system calls now return -EINVAL unless they specify a
hash algorithm. Intel Wireless Daemon (iwd) is one application issuing
such system calls (for EAP-TLS).
Closer analysis of the Embedded Linux Library (ell) used by iwd reveals
that the problem runs even deeper: When iwd uses TLS 1.1 or earlier, it
not only queries for keys, but performs sign/verify operations without
specifying a hash algorithm. These legacy TLS versions concatenate an
MD5 to a SHA-1 hash and omit the Full Hash Prefix:
https://git.kernel.org/pub/scm/libs/ell/ell.git/tree/ell/tls-suites.c#n97
TLS 1.1 was deprecated in 2021 by RFC 8996, but removal of support was
inadvertent in this case. It probably should be coordinated with iwd
maintainers first.
So reinstate support for such legacy protocols by defaulting to hash
algorithm "none" which uses an empty Full Hash Prefix.
If it is later on decided to remove TLS 1.1 support but still allow
KEYCTL_PKEY_QUERY without a hash algorithm, that can be achieved by
reverting the present commit and replacing it with the following patch:
https://lore.kernel.org/r/ZxalYZwH5UiGX5uj@wunner.de/
It's worth noting that Python's cryptography library gained support for
such legacy use cases very recently, so they do seem to still be a thing.
The Python developers identified IKE version 1 as another protocol
omitting the Full Hash Prefix:
https://github.com/pyca/cryptography/issues/10226https://github.com/pyca/cryptography/issues/5495
The author of those issues, Zoltan Kelemen, spent considerable effort
searching for test vectors but only found one in a 2019 blog post by
Kevin Jones. Add it to testmgr.h to verify correctness of this feature.
Examination of wpa_supplicant as well as various IKE daemons (libreswan,
strongswan, isakmpd, raccoon) has determined that none of them seems to
use the kernel's Key Retention Service, so iwd is the only affected user
space application known so far.
Fixes: 1e562deace ("crypto: rsassa-pkcs1 - Migrate to sig_alg backend")
Reported-by: Klara Modin <klarasmodin@gmail.com>
Tested-by: Klara Modin <klarasmodin@gmail.com>
Closes: https://lore.kernel.org/r/2ed09a22-86c0-4cf0-8bda-ef804ccb3413@gmail.com/
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
encrypt_blob(), decrypt_blob() and create_signature() were some of the
functions added in 2018 by
commit 5a30771832 ("KEYS: Provide missing asymmetric key subops for new
key type ops [ver #2]")
however, they've not been used.
Remove them.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Move crypto_simd_disabled_for_test to lib/ so that crypto_simd_usable()
can be used by library code.
This was discussed previously
(https://lore.kernel.org/linux-crypto/20220716062920.210381-4-ebiggers@kernel.org/)
but was not done because there was no use case yet. However, this is
now needed for the arm64 CRC32 library code.
Tested with:
export ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-
echo CONFIG_CRC32=y > .config
echo CONFIG_MODULES=y >> .config
echo CONFIG_CRYPTO=m >> .config
echo CONFIG_DEBUG_KERNEL=y >> .config
echo CONFIG_CRYPTO_MANAGER_DISABLE_TESTS=n >> .config
echo CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y >> .config
make olddefconfig
make -j$(nproc)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crc32c-generic is currently backed by the architecture's CRC-32c library
code, which may offer a variety of implementations depending on the
capabilities of the platform. These are not covered by the crypto
subsystem's fuzz testing capabilities because crc32c-generic is the
reference driver that the fuzzing logic uses as a source of truth.
Fix this by providing a crc32c-arch implementation which is based on the
arch library code if available, and modify crc32c-generic so it is
always based on the generic C implementation. If the arch has no CRC-32c
library code, this change does nothing.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crc32-generic is currently backed by the architecture's CRC-32 library
code, which may offer a variety of implementations depending on the
capabilities of the platform. These are not covered by the crypto
subsystem's fuzz testing capabilities because crc32-generic is the
reference driver that the fuzzing logic uses as a source of truth.
Fix this by providing a crc32-arch implementation which is based on the
arch library code if available, and modify crc32-generic so it is
always based on the generic C implementation. If the arch has no CRC-32
library code, this change does nothing.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove hard-coded strings by using the helper functions str_true_false()
and str_enabled_disabled().
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since commit 8f4f68e788 ("crypto: pcrypt - Fix hungtask for
PADATA_RESET"), the pcrypt encryption and decryption operations return
-EAGAIN when the CPU goes online or offline. In alg_test(), a WARN is
generated when pcrypt_aead_decrypt() or pcrypt_aead_encrypt() returns
-EAGAIN, the unnecessary panic will occur when panic_on_warn set 1.
Fix this issue by calling crypto layer directly without parallelization
in that case.
Fixes: 8f4f68e788 ("crypto: pcrypt - Fix hungtask for PADATA_RESET")
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit a7d45ba77d ("crypto: ecdsa - Register NIST P521 and extend test
suite") added support for ECDSA signature verification using NIST P521,
but forgot to amend the Kconfig help text. Fix it.
Fixes: a7d45ba77d ("crypto: ecdsa - Register NIST P521 and extend test suite")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit a2471684da ("crypto: ecdsa - Move X9.62 signature size
calculation into template") introduced ->max_size() and ->digest_size()
callbacks to struct sig_alg. They return an algorithm's maximum
signature size and digest size, respectively.
For algorithms which lack these callbacks, crypto_register_sig() was
amended to use the ->key_size() callback instead.
However the commit neglected to also amend sig_register_instance().
As a result, the ->max_size() and ->digest_size() callbacks remain NULL
pointers if instances do not define them. A KEYCTL_PKEY_QUERY system
call results in an oops for such instances:
BUG: kernel NULL pointer dereference, address: 0000000000000000
Call Trace:
software_key_query+0x169/0x370
query_asymmetric_key+0x67/0x90
keyctl_pkey_query+0x86/0x120
__do_sys_keyctl+0x428/0x480
do_syscall_64+0x4b/0x110
The only instances affected by this are "pkcs1(rsa, ...)".
Fix by moving the callback checks from crypto_register_sig() to
sig_prepare_alg(), which is also invoked by sig_register_instance().
Change the return type of sig_prepare_alg() from void to int to be able
to return errors. This matches other algorithm types, see e.g.
aead_prepare_alg() or ahash_prepare_alg().
Fixes: a2471684da ("crypto: ecdsa - Move X9.62 signature size calculation into template")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The Jitter RNG time delta is computed based on the difference of two
high-resolution, 64-bit time stamps. However, the test interface added
in 69f1c387ba only outputs the lower 32 bits of those time stamps. To
ensure all information is available during the evaluation process of
the Jitter RNG, output the full 64-bit time stamps.
Any clients collecting data from the test interface will need to be
updated to take this change into account.
Additionally, the size of the temporary buffer that holds the data for
user space has been clarified. Previously, this buffer was
JENT_TEST_RINGBUFFER_SIZE (= 1000) bytes in size, however that value
represents the number of samples held in the kernel space ring buffer,
with each sample taking 8 (previously 4) bytes.
Rather than increasing the size to allow for all 1000 samples to be
output, we keep it at 1000 bytes, but clarify that this means at most
125 64-bit samples will be output every time this interface is called.
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Joachim Vandersmissen <git@jvdsn.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
