The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.
Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.
But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.
[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Similar to what was done for the hash API, update the AEAD API to track
whether each transform has been keyed, and reject encryption/decryption
if a key is needed but one hasn't been set.
This isn't quite as important as the equivalent fix for the hash API
because AEADs always require a key, so are unlikely to be used without
one. Still, tracking the key will prevent accidental unkeyed use.
algif_aead also had to track the key anyway, so the new flag replaces
that and slightly simplifies the algif_aead implementation.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since commit 499a66e6b6 ("crypto: null - Remove default null
blkcipher"), crypto_get_default_null_skcipher2() and
crypto_put_default_null_skcipher2() are the same as their non-2
equivalents. So switch callers of the "2" versions over to the original
versions and remove the "2" versions.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This variable was increased and decreased without any protection.
Result was an occasional misscount and negative wrap around resulting
in false resource allocation failures.
Fixes: 7d2c3f54e6 ("crypto: af_alg - remove locking in async callback")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When invoking an asynchronous cipher operation, the invocation of the
callback may be performed before the subsequent operations in the
initial code path are invoked. The callback deletes the cipher request
data structure which implies that after the invocation of the
asynchronous cipher operation, this data structure must not be accessed
any more.
The setting of the return code size with the request data structure must
therefore be moved before the invocation of the asynchronous cipher
operation.
Fixes: e870456d8e ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The wait for data is a non-atomic operation that can sleep and therefore
potentially release the socket lock. The release of the socket lock
allows another thread to modify the context data structure. The waiting
operation for new data therefore must be called at the beginning of
recvmsg. This prevents a race condition where checks of the members of
the context data structure are performed by recvmsg while there is a
potential for modification of these values.
Fixes: e870456d8e ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In the AEAD interface for AF_ALG, the reference to the "null skcipher"
held by each tfm was being dropped in the wrong place -- when each
af_alg_ctx was freed instead of when the aead_tfm was freed. As
discovered by syzkaller, a specially crafted program could use this to
cause the null skcipher to be freed while it is still in use.
Fix it by dropping the reference in the right place.
Fixes: 72548b093e ("crypto: algif_aead - copy AAD from src to dst")
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The code paths protected by the socket-lock do not use or modify the
socket in a non-atomic fashion. The actions pertaining the socket do not
even need to be handled as an atomic operation. Thus, the socket-lock
can be safely ignored.
This fixes a bug regarding scheduling in atomic as the callback function
may be invoked in interrupt context.
In addition, the sock_hold is moved before the AIO encrypt/decrypt
operation to ensure that the socket is always present. This avoids a
tiny race window where the socket is unprotected and yet used by the AIO
operation.
Finally, the release of resources for a crypto operation is moved into a
common function of af_alg_free_resources.
Cc: <stable@vger.kernel.org>
Fixes: e870456d8e ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Reported-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Tested-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The TX SGL may contain SGL entries that are assigned a NULL page. This
may happen if a multi-stage AIO operation is performed where the data
for each stage is pointed to by one SGL entry. Upon completion of that
stage, af_alg_pull_tsgl will assign NULL to the SGL entry.
The NULL cipher used to copy the AAD from TX SGL to the destination
buffer, however, cannot handle the case where the SGL starts with an SGL
entry having a NULL page. Thus, the code needs to advance the start
pointer into the SGL to the first non-NULL entry.
This fixes a crash visible on Intel x86 32 bit using the libkcapi test
suite.
Cc: <stable@vger.kernel.org>
Fixes: 72548b093e ("crypto: algif_aead - copy AAD from src to dst")
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
algif starts several async crypto ops and waits for their completion.
Move it over to generic code doing the same.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Consolidate following data structures:
skcipher_async_req, aead_async_req -> af_alg_async_req
skcipher_rsgl, aead_rsql -> af_alg_rsgl
skcipher_tsgl, aead_tsql -> af_alg_tsgl
skcipher_ctx, aead_ctx -> af_alg_ctx
Consolidate following functions:
skcipher_sndbuf, aead_sndbuf -> af_alg_sndbuf
skcipher_writable, aead_writable -> af_alg_writable
skcipher_rcvbuf, aead_rcvbuf -> af_alg_rcvbuf
skcipher_readable, aead_readable -> af_alg_readable
aead_alloc_tsgl, skcipher_alloc_tsgl -> af_alg_alloc_tsgl
aead_count_tsgl, skcipher_count_tsgl -> af_alg_count_tsgl
aead_pull_tsgl, skcipher_pull_tsgl -> af_alg_pull_tsgl
aead_free_areq_sgls, skcipher_free_areq_sgls -> af_alg_free_areq_sgls
aead_wait_for_wmem, skcipher_wait_for_wmem -> af_alg_wait_for_wmem
aead_wmem_wakeup, skcipher_wmem_wakeup -> af_alg_wmem_wakeup
aead_wait_for_data, skcipher_wait_for_data -> af_alg_wait_for_data
aead_data_wakeup, skcipher_data_wakeup -> af_alg_data_wakeup
aead_sendmsg, skcipher_sendmsg -> af_alg_sendmsg
aead_sendpage, skcipher_sendpage -> af_alg_sendpage
aead_async_cb, skcipher_async_cb -> af_alg_async_cb
aead_poll, skcipher_poll -> af_alg_poll
Split out the following common code from recvmsg:
af_alg_alloc_areq: allocation of the request data structure for the
cipher operation
af_alg_get_rsgl: creation of the RX SGL anchored in the request data
structure
The following changes to the implementation without affecting the
functionality have been applied to synchronize slightly different code
bases in algif_skcipher and algif_aead:
The wakeup in af_alg_wait_for_data is triggered when either more data
is received or the indicator that more data is to be expected is
released. The first is triggered by user space, the second is
triggered by the kernel upon finishing the processing of data
(i.e. the kernel is ready for more).
af_alg_sendmsg uses size_t in min_t calculation for obtaining len.
Return code determination is consistent with algif_skcipher. The
scope of the variable i is reduced to match algif_aead. The type of the
variable i is switched from int to unsigned int to match algif_aead.
af_alg_sendpage does not contain the superfluous err = 0 from
aead_sendpage.
af_alg_async_cb requires to store the number of output bytes in
areq->outlen before the AIO callback is triggered.
The POLLIN / POLLRDNORM is now set when either not more data is given or
the kernel is supplied with data. This is consistent to the wakeup from
sleep when the kernel waits for data.
The request data structure is extended by the field last_rsgl which
points to the last RX SGL list entry. This shall help recvmsg
implementation to chain the RX SGL to other SG(L)s if needed. It is
currently used by algif_aead which chains the tag SGL to the RX SGL
during decryption.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Use the NULL cipher to copy the AAD and PT/CT from the TX SGL
to the RX SGL. This allows an in-place crypto operation on the
RX SGL for encryption, because the TX data is always smaller or
equal to the RX data (the RX data will hold the tag).
For decryption, a per-request TX SGL is created which will only hold
the tag value. As the RX SGL will have no space for the tag value and
an in-place operation will not write the tag buffer, the TX SGL with the
tag value is chained to the RX SGL. This now allows an in-place
crypto operation.
For example:
* without the patch:
kcapi -x 2 -e -c "gcm(aes)" -p 89154d0d4129d322e4487bafaa4f6b46 -k c0ece3e63198af382b5603331cc23fa8 -i 7e489b83622e7228314d878d -a afcd7202d621e06ca53b70c2bdff7fb2 -l 16 -u -s
00000000000000000000000000000000f4a3eacfbdadd3b1a17117b1d67ffc1f1e21efbbc6d83724a8c296e3bb8cda0c
* with the patch:
kcapi -x 2 -e -c "gcm(aes)" -p 89154d0d4129d322e4487bafaa4f6b46 -k c0ece3e63198af382b5603331cc23fa8 -i 7e489b83622e7228314d878d -a afcd7202d621e06ca53b70c2bdff7fb2 -l 16 -u -s
afcd7202d621e06ca53b70c2bdff7fb2f4a3eacfbdadd3b1a17117b1d67ffc1f1e21efbbc6d83724a8c296e3bb8cda0c
Tests covering this functionality have been added to libkcapi.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If no data has been processed during recvmsg, return the error code.
This covers all errors received during non-AIO operations.
If any error occurs during a synchronous operation in addition to
-EIOCBQUEUED or -EBADMSG (like -ENOMEM), it should be relayed to the
caller.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The updated memory management is described in the top part of the code.
As one benefit of the changed memory management, the AIO and synchronous
operation is now implemented in one common function. The AF_ALG
operation uses the async kernel crypto API interface for each cipher
operation. Thus, the only difference between the AIO and sync operation
types visible from user space is:
1. the callback function to be invoked when the asynchronous operation
is completed
2. whether to wait for the completion of the kernel crypto API operation
or not
The change includes the overhaul of the TX and RX SGL handling. The TX
SGL holding the data sent from user space to the kernel is now dynamic
similar to algif_skcipher. This dynamic nature allows a continuous
operation of a thread sending data and a second thread receiving the
data. These threads do not need to synchronize as the kernel processes
as much data from the TX SGL to fill the RX SGL.
The caller reading the data from the kernel defines the amount of data
to be processed. Considering that the interface covers AEAD
authenticating ciphers, the reader must provide the buffer in the
correct size. Thus the reader defines the encryption size.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
This patch uses refcount_inc_not_zero() instead of
atomic_inc_not_zero_hint() due to absense of a _hint()
version of refcount API. If the hint() version must
be used, we might need to revisit API.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull crypto updates from Herbert Xu:
"Here is the crypto update for 4.12:
API:
- Add batch registration for acomp/scomp
- Change acomp testing to non-unique compressed result
- Extend algorithm name limit to 128 bytes
- Require setkey before accept(2) in algif_aead
Algorithms:
- Add support for deflate rfc1950 (zlib)
Drivers:
- Add accelerated crct10dif for powerpc
- Add crc32 in stm32
- Add sha384/sha512 in ccp
- Add 3des/gcm(aes) for v5 devices in ccp
- Add Queue Interface (QI) backend support in caam
- Add new Exynos RNG driver
- Add ThunderX ZIP driver
- Add driver for hardware random generator on MT7623 SoC"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (101 commits)
crypto: stm32 - Fix OF module alias information
crypto: algif_aead - Require setkey before accept(2)
crypto: scomp - add support for deflate rfc1950 (zlib)
crypto: scomp - allow registration of multiple scomps
crypto: ccp - Change ISR handler method for a v5 CCP
crypto: ccp - Change ISR handler method for a v3 CCP
crypto: crypto4xx - rename ce_ring_contol to ce_ring_control
crypto: testmgr - Allow ecb(cipher_null) in FIPS mode
Revert "crypto: arm64/sha - Add constant operand modifier to ASM_EXPORT"
crypto: ccp - Disable interrupts early on unload
crypto: ccp - Use only the relevant interrupt bits
hwrng: mtk - Add driver for hardware random generator on MT7623 SoC
dt-bindings: hwrng: Add Mediatek hardware random generator bindings
crypto: crct10dif-vpmsum - Fix missing preempt_disable()
crypto: testmgr - replace compression known answer test
crypto: acomp - allow registration of multiple acomps
hwrng: n2 - Use devm_kcalloc() in n2rng_probe()
crypto: chcr - Fix error handling related to 'chcr_alloc_shash'
padata: get_next is never NULL
crypto: exynos - Add new Exynos RNG driver
...
Some cipher implementations will crash if you try to use them
without calling setkey first. This patch adds a check so that
the accept(2) call will fail with -ENOKEY if setkey hasn't been
done on the socket yet.
Fixes: 400c40cf78 ("crypto: algif - add AEAD support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The algif_aead completion function tries to deduce the aead_request
from the crypto_async_request argument. This is broken because
the API does not guarantee that the same request will be pased to
the completion function. Only the value of req->data can be used
in the completion function.
This patch fixes it by storing a pointer to sk in areq and using
that instead of passing in sk through req->data.
Fixes: 83094e5e9e ("crypto: af_alg - add async support to...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Linus Torvalds
Kees Cook
Christoph Hellwig
Eric Biggers
Herbert Xu
Jonathan Cameron
Stephan Mueller
Gilad Ben-Yossef
Reshetova, Elena
Herbert Xu
Ingo Molnar
Harsh Jain