C99 6.7.8.17 says that when an undesignated initialiser is used, only
the first element of a union is initialised. If the first element is not
the largest within the union, how the remaining space is initialised is
up to the compiler.
GCC extends the initialiser to the entire union, while Clang treats the
remainder as padding, and so initialises according to whatever
automatic/implicit initialisation rules are currently active.
When Linux is compiled with CONFIG_INIT_STACK_ALL_PATTERN,
-ftrivial-auto-var-init=pattern is added to the kernel CFLAGS. This flag
sets the policy for automatic/implicit initialisation of variables on
the stack.
Taken together, this means that when compiling under
CONFIG_INIT_STACK_ALL_PATTERN on Clang, the "zero" initialiser will only
zero the first element in a union, and the rest will be filled with a
pattern. This is significant for aes_ctx_t, which in
aes_encrypt_atomic() and aes_decrypt_atomic() is initialised to zero,
but then used as a gcm_ctx_t, which is the fifth element in the union,
and thus gets pattern initialisation. Later, it's assumed to be zero,
resulting in a hang.
As confusing and undiscoverable as it is, by the spec, we are at fault
when we initialise a structure containing a union with the zero
initializer. As such, this commit replaces these uses with an explicit
memset(0).
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#16135Closes#16206
Currently the temporary buffer in which decryption takes place
isn't cleared on context destruction. Further in some routines we
fail to call gcm_clear_ctx() on error exit. Both flaws may result
in leaking sensitive data.
We follow best practices and zero out the plaintext buffer before
freeing the memory holding it. Also move all cleanup into
gcm_clear_ctx() and call it on any context destruction.
The performance impact should be negligible.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rob Norris <robn@despairlabs.com>
Signed-off-by: Attila Fülöp <attila@fueloep.org>
Closes#14528
bcopy() has a confusing argument order and is actually a move, not a
copy; they're all deprecated since POSIX.1-2001 and removed in -2008,
and we shim them out to mem*() on Linux anyway
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#12996
It's the only one actually used
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#12901
Unfortunately macOS has obj-C keyword "fallthrough" in the OS headers.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Damian Szuberski <szuberskidamian@gmail.com>
Signed-off-by: Jorgen Lundman <lundman@lundman.net>
Closes#13097
Evaluated every variable that lives in .data (and globals in .rodata)
in the kernel modules, and constified/eliminated/localised them
appropriately. This means that all read-only data is now actually
read-only data, and, if possible, at file scope. A lot of previously-
global-symbols became inlinable (and inlined!) constants. Probably
not in a big Wowee Performance Moment, but hey.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#12899
After progressively folding away null cases, it turns out there's
/literally/ nothing there, even if some things are part of the
Solaris SPARC DDI/DKI or the seventeen module types (some doubled for
32-bit userland), or the entire modctl syscall definition.
Nothing.
Initialisation is handled in illumos-crypto.c,
which calls all the initialisers directly
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Attila Fülöp <attila@fueloep.org>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#12895Closes#12902
As of the Linux 5.9 kernel a fallthrough macro has been added which
should be used to anotate all intentional fallthrough paths. Once
all of the kernel code paths have been updated to use fallthrough
the -Wimplicit-fallthrough option will because the default. To
avoid warnings in the OpenZFS code base when this happens apply
the fallthrough macro.
Additional reading: https://lwn.net/Articles/794944/
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#12441
While evaluating other assembler implementations it turns out that
the precomputed hash subkey tables vary in size, from 8*16 bytes
(avx2/avx512) up to 48*16 bytes (avx512-vaes), depending on the
implementation.
To be able to handle the size differences later, allocate
`gcm_Htable` dynamically rather then having a fixed size array, and
adapt consumers.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Attila Fülöp <attila@fueloep.org>
Closes#11102
These paths are never exercised, as the parameters given are always
different cipher and plaintext `crypto_data_t` pointers.
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Attila Fueloep <attila@fueloep.org>
Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Closes#9661Closes#10015
Contrary to initial testing we cannot rely on these kernels to
invalidate the per-cpu FPU state and restore the FPU registers.
Nor can we guarantee that the kernel won't modify the FPU state
which we saved in the task struck.
Therefore, the kfpu_begin() and kfpu_end() functions have been
updated to save and restore the FPU state using our own dedicated
per-cpu FPU state variables.
This has the additional advantage of allowing us to use the FPU
again in user threads. So we remove the code which was added to
use task queues to ensure some functions ran in kernel threads.
Reviewed-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #9346Closes#9403
Move platform specific Linux headers under include/os/linux/.
Update the build system accordingly to detect the platform.
This lays some of the initial groundwork to supporting building
for other platforms.
As part of this change it was necessary to create both a user
and kernel space sys/simd.h header which can be included in
either context. No functional change, the source has been
refactored and the relevant #include's updated.
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Signed-off-by: Matthew Macy <mmacy@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#9198
Restore the SIMD optimization for 4.19.38 LTS, 4.14.120 LTS,
and 5.0 and newer kernels. This is accomplished by leveraging
the fact that by definition dedicated kernel threads never need
to concern themselves with saving and restoring the user FPU state.
Therefore, they may use the FPU as long as we can guarantee user
tasks always restore their FPU state before context switching back
to user space.
For the 5.0 and 5.1 kernels disabling preemption and local
interrupts is sufficient to allow the FPU to be used. All non-kernel
threads will restore the preserved user FPU state.
For 5.2 and latter kernels the user FPU state restoration will be
skipped if the kernel determines the registers have not changed.
Therefore, for these kernels we need to perform the additional
step of saving and restoring the FPU registers. Invalidating the
per-cpu global tracking the FPU state would force a restore but
that functionality is private to the core x86 FPU implementation
and unavailable.
In practice, restricting SIMD to kernel threads is not a major
restriction for ZFS. The vast majority of SIMD operations are
already performed by the IO pipeline. The remaining cases are
relatively infrequent and can be handled by the generic code
without significant impact. The two most noteworthy cases are:
1) Decrypting the wrapping key for an encrypted dataset,
i.e. `zfs load-key`. All other encryption and decryption
operations will use the SIMD optimized implementations.
2) Generating the payload checksums for a `zfs send` stream.
In order to avoid making any changes to the higher layers of ZFS
all of the `*_get_ops()` functions were updated to take in to
consideration the calling context. This allows for the fastest
implementation to be used as appropriate (see kfpu_allowed()).
The only other notable instance of SIMD operations being used
outside a kernel thread was at module load time. This code
was moved in to a taskq in order to accommodate the new kernel
thread restriction.
Finally, a few other modifications were made in order to further
harden this code and facilitate testing. They include updating
each implementations operations structure to be declared as a
constant. And allowing "cycle" to be set when selecting the
preferred ops in the kernel as well as user space.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#8754Closes#8793Closes#8965
- Add two new module parameters to icp (icp_aes_impl, icp_gcm_impl)
that control the crypto implementation. At the moment there is a
choice between generic and aesni (on platforms that support it).
- This enables support for AES-NI and PCLMULQDQ-NI on AMD Family
15h (bulldozer) and newer CPUs (zen).
- Modify aes_key_t to track what implementation it was generated
with as key schedules generated with various implementations
are not necessarily interchangable.
Reviewed by: Gvozden Neskovic <neskovic@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Signed-off-by: Nathaniel R. Lewis <linux.robotdude@gmail.com>
Closes#7102Closes#7103
Fix build errors with gcc 7.2.0 on Gentoo with kernel 4.14
built with CONFIG_GCC_PLUGIN_RANDSTRUCT=y such as:
module/nvpair/nvpair.c:2810:2:error:
positional initialization of field in ?struct? declared with
'designated_init' attribute [-Werror=designated-init]
nvs_native_nvlist,
^~~~~~~~~~~~~~~~~
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Mark Wright <gienah@gentoo.org>
Closes#5390Closes#6903
A port of the Illumos Crypto Framework to a Linux kernel module (found
in module/icp). This is needed to do the actual encryption work. We cannot
use the Linux kernel's built in crypto api because it is only exported to
GPL-licensed modules. Having the ICP also means the crypto code can run on
any of the other kernels under OpenZFS. I ended up porting over most of the
internals of the framework, which means that porting over other API calls (if
we need them) should be fairly easy. Specifically, I have ported over the API
functions related to encryption, digests, macs, and crypto templates. The ICP
is able to use assembly-accelerated encryption on amd64 machines and AES-NI
instructions on Intel chips that support it. There are place-holder
directories for similar assembly optimizations for other architectures
(although they have not been written).
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4329
Rob N
Attila Fülöp
Tino Reichardt
наб
Jorgen Lundman
Brian Behlendorf
Dirkjan Bussink
Matthew Macy
Nathan Lewis
Mark Wright
George Melikov
luozhengzheng
Tom Caputi