commit 8c3fffe3993b06dd1955a79bd2f0f3b143d259b3 upstream.
In commit 71052dcf4be70 ("crypto: scompress - Use per-CPU struct instead
multiple variables") I accidentally initialized multiple times the memory on a
random CPU. I should have initialize the memory on every CPU like it has
been done earlier. I didn't notice this because the scheduler didn't
move the task to another CPU.
Guenter managed to do that and the code crashed as expected.
Allocate / free per-CPU memory on each CPU.
Fixes: 71052dcf4be70 ("crypto: scompress - Use per-CPU struct instead multiple variables")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit a132ff91717c28498c602e62824f0684a02c8832)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
[ Upstream commit 71052dcf4be70be4077817297dcde7b155e745f2 ]
Two per-CPU variables are allocated as pointer to per-CPU memory which
then are used as scratch buffers.
We could be smart about this and use instead a per-CPU struct which
contains the pointers already and then we need to allocate just the
scratch buffers.
Add a lock to the struct. By doing so we can avoid the get_cpu()
statement and gain lockdep coverage (if enabled) to ensure that the lock
is always acquired in the right context. On non-preemptible kernels the
lock vanishes.
It is okay to use raw_cpu_ptr() in order to get a pointer to the struct
since it is protected by the spinlock.
The diffstat of this is negative and according to size scompress.o:
text data bss dec hex filename
1847 160 24 2031 7ef dbg_before.o
1754 232 4 1990 7c6 dbg_after.o
1799 64 24 1887 75f no_dbg-before.o
1703 88 4 1795 703 no_dbg-after.o
The overall size increase difference is also negative. The increase in
the data section is only four bytes without lockdep.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stable-dep-of: 744e1885922a ("crypto: scomp - fix req->dst buffer overflow")
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit f8f261f9ade28894f5b547d1ec2a905308990f28)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
[ Upstream commit 6a4d1b18ef00a7b182740b7b4d8a0fcd317368f8 ]
If scomp_acomp_comp_decomp() fails to allocate memory for the
destination then we never copy back the data we compressed.
It is probably best to return an error code instead 0 in case of
failure.
I haven't found any user that is using acomp_request_set_params()
without the `dst' buffer so there is probably no harm.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stable-dep-of: 744e1885922a ("crypto: scomp - fix req->dst buffer overflow")
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 1915874d67287ba1ab71825ae6a4efbb2a0e2b11)
[fix trivial conflict due to missing commit
8cd579d2794b90f810e534e75783ba78cdc91a07 ("crypto: scompress - use
sgl_alloc() and sgl_free()")]
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
The scompress code allocates 2 x 128 KB of scratch buffers for each CPU,
so that clients of the async API can use synchronous implementations
even from atomic context. However, on systems such as Cavium Thunderx
(which has 96 cores), this adds up to a non-negligible 24 MB. Also,
32-bit systems may prefer to use their precious vmalloc space for other
things,especially since there don't appear to be any clients for the
async compression API yet.
So let's defer allocation of the scratch buffers until the first time
we allocate an acompress cipher based on an scompress implementation.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When allocating the per-CPU scratch buffers, we allocate the source
and destination buffers separately, but bail immediately if the second
allocation fails, without freeing the first one. Fix that.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Due to the use of per-CPU buffers, scomp_acomp_comp_decomp() executes
with preemption disabled, and so whether the CRYPTO_TFM_REQ_MAY_SLEEP
flag is set is irrelevant, since we cannot sleep anyway. So disregard
the flag, and use GFP_ATOMIC unconditionally.
Cc: <stable@vger.kernel.org> # v4.10+
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add crypto_register_scomps and crypto_unregister_scomps to allow
the registration of multiple implementations with one call.
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Continuing from this commit: 52f5684c8e1e
("kernel: use macros from compiler.h instead of __attribute__((...))")
I submitted 4 total patches. They are part of task I've taken up to
increase compiler portability in the kernel. I've cleaned up the
subsystems under /kernel /mm /block and /security, this patch targets
/crypto.
There is <linux/compiler.h> which provides macros for various gcc specific
constructs. Eg: __weak for __attribute__((weak)). I've cleaned all
instances of gcc specific attributes with the right macros for the crypto
subsystem.
I had to make one additional change into compiler-gcc.h for the case when
one wants to use this: __attribute__((aligned) and not specify an alignment
factor. From the gcc docs, this will result in the largest alignment for
that data type on the target machine so I've named the macro
__aligned_largest. Please advise if another name is more appropriate.
Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add a synchronous back-end (scomp) to acomp. This allows to easily
expose the already present compression algorithms in LKCF via acomp.
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
