Adjust cra_flags to add CRYPTO_NEED_FALLBACK only for AES ciphers, where
AES-192 is not handled by the qce hardware, and don't allocate & free
the fallback skcipher for other algorithms.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Update the IV after the completion of each cipher operation.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When ctr-aes-qce is used for gcm-mode, an extra sg entry for the
authentication tag is present, causing trouble when the qce driver
prepares the dst-results sg table for dma.
It computes the number of entries needed with sg_nents_for_len, leaving
out the tag entry. Then it creates a sg table with that number plus
one, used to store a result buffer.
When copying the sg table, there's no limit to the number of entries
copied, so the extra slot is filled with the authentication tag sg.
When the driver tries to add the result sg, the list is full, and it
returns EINVAL.
By limiting the number of sg entries copied to the dest table, the slot
for the result buffer is guaranteed to be unused.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
XTS-mode uses two keys, so the keysizes should be doubled in
skcipher_def, and halved when checking if it is AES-128/192/256.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Set blocksize of ctr-aes-qce to 1, so it can operate as a stream cipher,
adding the definition for chucksize instead, where the underlying block
size belongs.
Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch introduces the skcipher_ialg_simple helper which fetches
the crypto_alg structure from a simple skcipher instance's spawn.
This allows us to remove the third argument from the function
skcipher_alloc_instance_simple.
In doing so the reference count to the algorithm is now maintained
by the Crypto API and the caller no longer needs to drop the alg
refcount.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Freed work request skbs when connection terminates.
enqueue_wr()/ dequeue_wr() is shared between softirq
and application contexts, should be protected by socket
lock. Moved dequeue_wr() to appropriate file.
Signed-off-by: Vinay Kumar Yadav <vinay.yadav@chelsio.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Added support to set 256 bit key to the hardware from
setsockopt for AES256-GCM based ciphers.
Signed-off-by: Vinay Kumar Yadav <vinay.yadav@chelsio.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The i.MX8M Mini uses the same crypto engine as the i.MX8MQ, but
the driver is restricting the check to just the i.MX8MQ.
This patch expands the check for either i.MX8MQ or i.MX8MM.
Signed-off-by: Adam Ford <aford173@gmail.com>
Tested-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reviewed-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes crypto_grab_spawn to retain the reference count
on the algorithm. This is because the caller needs to access the
algorithm parameters and without the reference count the algorithm
can be freed at any time.
The reference count will be subsequently dropped by the crypto API
once the instance has been registered. The helper crypto_drop_spawn
will also conditionally drop the reference count depending on whether
it has been registered.
Note that the code is actually added to crypto_init_spawn. However,
unless the caller activates this by setting spawn->dropref beforehand
then nothing happens. The only caller that sets dropref is currently
crypto_grab_spawn.
Once all legacy users of crypto_init_spawn disappear, then we can
kill the dropref flag.
Internally each instance will maintain a list of its spawns prior
to registration. This memory used by this list is shared with
other fields that are only used after registration. In order for
this to work a new flag spawn->registered is added to indicate
whether spawn->inst can be used.
Fixes: d6ef2f198d ("crypto: api - Add crypto_grab_spawn primitive")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The sun4i_ss_pm_ops is not referenced outside the driver
except via a pointer, so make it static to avoid the following
warning:
drivers/crypto/allwinner/sun4i-ss/sun4i-ss-core.c:276:25: warning: symbol 'sun4i_ss_pm_ops' was not declared. Should it be static?
Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.
By using dma_request_chan() directly the driver can support deferred
probing against DMA.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.
By using dma_request_chan() directly the driver can support deferred
probing against DMA.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Somehow these were dropped when Zinc was being integrated, which is
problematic, because testing the library interface for Curve25519 is
important.. This commit simply adds them back and wires them in in the
same way that the blake2s selftests are wired in.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Some of the algorithm unregistration functions return -ENOENT when asked
to unregister a non-registered algorithm, while others always return 0
or always return void. But no users check the return value, except for
two of the bulk unregistration functions which print a message on error
but still always return 0 to their caller, and crypto_del_alg() which
calls crypto_unregister_instance() which always returns 0.
Since unregistering a non-registered algorithm is always a kernel bug
but there isn't anything callers should do to handle this situation at
runtime, let's simplify things by making all the unregistration
functions return void, and moving the error message into
crypto_unregister_alg() and upgrading it to a WARN().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In an effort to clarify and simplify the annotation of assembly functions
in the kernel new macros have been introduced. These replace ENTRY and
ENDPROC and also add a new annotation for static functions which previously
had no ENTRY equivalent. Update the annotations in the crypto code to the
new macros.
There are a small number of files imported from OpenSSL where the assembly
is generated using perl programs, these are not currently annotated at all
and have not been modified.
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The CTR transfer works in fragments of data of maximum 1 MByte because
of the 16 bit CTR counter embedded in the IP. Fix the CTR counter
overflow handling for messages larger than 1 MByte.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 781a08d974 ("crypto: atmel-aes - Fix counter overflow in CTR mode")
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
chcr driver was not using the number of channels from lld and
assuming that there are always two channels available. With following
patch chcr will use number of channel as passed by cxgb4.
Signed-off-by: Ayush Sawal <ayush.sawal@chelsio.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Do not update the IV in case of errors.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Even when deferring, we would like to know what caused it.
Update dev_warn to dev_err because if the DMA init fails,
the probe is stopped.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The 'direction' member of the dma_slave_config will be going away
as it duplicates the direction given in the prepare call.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
device_terminate_all() is used to abort all the pending and
ongoing transfers on the channel, it should be used just in the
error path.
Also, dmaengine_terminate_all() is deprecated and one should use
dmaengine_terminate_async() or dmaengine_terminate_sync(). The method
is not used in atomic context, use dmaengine_terminate_sync().
A secondary aspect of this patch is that it luckily avoids a deadlock
between atmel_aes and at_hdmac.c. While in tasklet with the lock held,
the dma controller invokes the client callback (dmaengine_terminate_all),
which tries to get the same lock. The at_hdmac fix would be to drop the
lock before invoking the client callback, a fix on at_hdmac will follow.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently CONFIG_CRYPTO_DEV_AMLOGIC_GXL=y implicitly depends on
CONFIG_HAS_IOMEM=y; consequently, on architectures without IOMEM we get
the following build error:
ld: drivers/crypto/amlogic/amlogic-gxl-core.o: in function `meson_crypto_probe':
drivers/crypto/amlogic/amlogic-gxl-core.c:240: undefined reference to `devm_platform_ioremap_resource'
Fix the build error by adding the unspecified dependency.
Reported-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently CONFIG_CRYPTO_DEV_SAFEXCEL=y implicitly depends on
CONFIG_HAS_IOMEM=y; consequently, on architectures without IOMEM we get
the following build error:
ld: drivers/crypto/inside-secure/safexcel.o: in function `safexcel_probe':
drivers/crypto/inside-secure/safexcel.c:1692: undefined reference to `devm_platform_ioremap_resource'
Fix the build error by adding the unspecified dependency.
Reported-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes another hang case on the EIP97 caused by sending
invalidation tokens to the hardware when doing basic (3)DES ECB/CBC
operations. Invalidation tokens are an EIP197 feature and needed nor
supported by the EIP97. So they should not be sent for that device.
Signed-off-by: Pascal van Leeuwen <pvanleeuwen@rambus.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The EIP97 hardware cannot handle zero length input data and will (usually)
hang when presented with this anyway. This patch converts any zero length
input to a 1 byte dummy input to prevent this hanging.
Signed-off-by: Pascal van Leeuwen <pvanleeuwen@rambus.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Due to the additions of support for modes like AES-CCM and AES-GCM, which
require large command tokens, the size of the descriptor has grown such that
it now does not fit into the descriptor cache of a standard EIP97 anymore.
This means that the driver no longer works on the Marvell Armada 3700LP chip
(as used on e.g. Espressobin) that it has always supported.
Additionally, performance on EIP197's like Marvell A8K may also degrade
due to being able to fit less descriptors in the on-chip cache.
Putting these tokens into the descriptor was really a hack and not how the
design was supposed to be used - resource allocation did not account for it.
So what this patch does, is move the command token out of the descriptor.
To avoid having to allocate buffers on the fly for these command tokens,
they are stuffed in a "shadow ring", which is a circular buffer of fixed
size blocks that runs in lock-step with the descriptor ring. i.e. there is
one token block per descriptor. The descriptor ring itself is then pre-
populated with the pointers to these token blocks so these do not need to
be filled in when building the descriptors later.
Signed-off-by: Pascal van Leeuwen <pvanleeuwen@rambus.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y, the first lookup of an
algorithm that needs to be instantiated using a template will always get
the generic implementation, even when an accelerated one is available.
This happens because the extra self-tests for the accelerated
implementation allocate the generic implementation for comparison
purposes, and then crypto_alg_tested() for the generic implementation
"fulfills" the original request (i.e. sets crypto_larval::adult).
This patch fixes this by only fulfilling the original request if
we are currently the best outstanding larval as judged by the
priority. If we're not the best then we will ask all waiters on
that larval request to retry the lookup.
Note that this patch introduces a behaviour change when the module
providing the new algorithm is unregistered during the process.
Previously we would have failed with ENOENT, after the patch we
will instead redo the lookup.
Fixes: 9a8a6b3f09 ("crypto: testmgr - fuzz hashes against...")
Fixes: d435e10e67 ("crypto: testmgr - fuzz skciphers against...")
Fixes: 40153b10d9 ("crypto: testmgr - fuzz AEADs against...")
Reported-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Previously double buffering was used for storing previous and next
"less-than-block-size" bytes. Double buffering can be removed by moving
the copy of next "less-than-block-size" bytes after current request is
executed by HW.
Signed-off-by: Andrei Botila <andrei.botila@nxp.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Previously double buffering was used for storing previous and next
"less-than-block-size" bytes. Double buffering can be removed by moving
the copy of next "less-than-block-size" bytes after current request is
executed by HW.
Signed-off-by: Andrei Botila <andrei.botila@nxp.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since tasklet is needed to be initialized before registering IRQ
handler, adjust the position of tasklet_init to fix the wrong order.
Besides, to fix the missed tasklet_kill, this patch adds a helper
function and uses devm_add_action to kill the tasklet automatically.
Fixes: ce92136843 ("crypto: picoxcell - add support for the picoxcell crypto engines")
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Just like in 4a97bfc796 ("crypto: hisilicon - no need to check return
value of debugfs_create functions"), there still is no need to ever
check the return value. The function can work or not, but the code
logic should never do something different based on this.
Cc: Zhou Wang <wangzhou1@hisilicon.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Extend the functionality of AMD Secure Processor (SP) driver by
providing an in-kernel API to submit commands to TEE ring buffer for
processing by Trusted OS running on AMD Secure Processor.
Following TEE commands are supported by Trusted OS:
* TEE_CMD_ID_LOAD_TA : Load Trusted Application (TA) binary into
TEE environment
* TEE_CMD_ID_UNLOAD_TA : Unload TA binary from TEE environment
* TEE_CMD_ID_OPEN_SESSION : Open session with loaded TA
* TEE_CMD_ID_CLOSE_SESSION : Close session with loaded TA
* TEE_CMD_ID_INVOKE_CMD : Invoke a command with loaded TA
* TEE_CMD_ID_MAP_SHARED_MEM : Map shared memory
* TEE_CMD_ID_UNMAP_SHARED_MEM : Unmap shared memory
Linux AMD-TEE driver will use this API to submit command buffers
for processing in Trusted Execution Environment. The AMD-TEE driver
shall be introduced in a separate patch.
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Adds a PCI device entry for Raven Ridge. Raven Ridge is an APU with a
dedicated AMD Secure Processor having Trusted Execution Environment (TEE)
support. The TEE provides a secure environment for running Trusted
Applications (TAs) which implement security-sensitive parts of a feature.
This patch configures AMD Secure Processor's TEE interface by initializing
a ring buffer (shared memory between Rich OS and Trusted OS) which can hold
multiple command buffer entries. The TEE interface is facilitated by a set
of CPU to PSP mailbox registers.
The next patch will address how commands are submitted to the ring buffer.
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Read PSP feature register to check for TEE (Trusted Execution Environment)
support.
If neither SEV nor TEE is supported by PSP, then skip PSP initialization.
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
PSP can support both SEV and TEE interface. Therefore, move
SEV specific registers to a dedicated data structure.
TEE interface specific registers will be added in a later
patch.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The PSP (Platform Security Processor) provides support for key management
commands in Secure Encrypted Virtualization (SEV) mode, along with
software-based Trusted Execution Environment (TEE) to enable third-party
Trusted Applications.
Therefore, introduce psp-dev.c and psp-dev.h files, which can invoke
SEV (or TEE) initialization based on platform feature support.
TEE interface support will be introduced in a later patch.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This is a preliminary patch for creating a generic PSP device driver
file, which will have support for both SEV and TEE (Trusted Execution
Environment) interface.
This patch does not introduce any new functionality, but simply renames
psp-dev.c and psp-dev.h files to sev-dev.c and sev-dev.h files
respectively.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Co-developed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
Acked-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch switches hmac over to the new init_tfm/exit_tfm interface
as opposed to cra_init/cra_exit. This way the shash API can make
sure that descsize does not exceed the maximum.
This patch also adds the API helper shash_alg_instance.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch switches padlock-sha over to the new init_tfm/exit_tfm
interface as opposed to cra_init/cra_exit. This way the shash API
can make sure that descsize does not exceed the maximum.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The shash interface supports a dynamic descsize field because of
the presence of fallbacks (it's just padlock-sha actually, perhaps
we can remove it one day). As it is the API does not verify the
setting of descsize at all. It is up to the individual algorithms
to ensure that descsize does not exceed the specified maximum value
of HASH_MAX_DESCSIZE (going above would cause stack corruption).
In order to allow the API to impose this limit directly, this patch
adds init_tfm/exit_tfm hooks to the shash_alg structure. We can
then verify the descsize setting in the API directly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch explains the logic behind crypto_remove_spawns and its
underling crypto_more_spawns.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently when a spawn is removed we will zap its alg field.
This is racy because the spawn could belong to an unregistered
instance which may dereference the spawn->alg field.
This patch fixes this by keeping spawn->alg constant and instead
adding a new spawn->dead field to indicate that a spawn is going
away.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The function crypto_spawn_alg is racy because it drops the lock
before shooting the dying algorithm. The algorithm could disappear
altogether before we shoot it.
This patch fixes it by moving the shooting into the locked section.
Fixes: 6bfd48096f ("[CRYPTO] api: Added spawns")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
arc4 is no longer considered secure, so it shouldn't be used, even as
just an example. Mention serpent and chacha20 instead.
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>
We need to check whether spawn->alg is NULL under lock as otherwise
the algorithm could be removed from under us after we have checked
it and found it to be non-NULL. This could cause us to remove the
spawn from a non-existent list.
Fixes: 7ede5a5ba5 ("crypto: api - Fix crypto_drop_spawn crash...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
