There have been a pretty ridiculous number of issues with initializing
the report structures that are copied to userspace by NETLINK_CRYPTO.
Commit 4473710df1 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME
expansion") replaced some strncpy()s with strlcpy()s, thereby
introducing information leaks. Later two other people tried to replace
other strncpy()s with strlcpy() too, which would have introduced even
more information leaks:
- https://lore.kernel.org/patchwork/patch/954991/
- https://patchwork.kernel.org/patch/10434351/
Commit cac5818c25 ("crypto: user - Implement a generic crypto
statistics") also uses the buggy strlcpy() approach and therefore leaks
uninitialized memory to userspace. A fix was proposed, but it was
originally incomplete.
Seeing as how apparently no one can get this right with the current
approach, change all the reporting functions to:
- Start by memsetting the report structure to 0. This guarantees it's
always initialized, regardless of what happens later.
- Initialize all strings using strscpy(). This is safe after the
memset, ensures null termination of long strings, avoids unnecessary
work, and avoids the -Wstringop-truncation warnings from gcc.
- Use sizeof(var) instead of sizeof(type). This is more robust against
copy+paste errors.
For simplicity, also reuse the -EMSGSIZE return value from nla_put().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add crypto_register_acomps and crypto_unregister_acomps 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: 52f5684c8e
("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>
Add acomp, an asynchronous compression api that uses scatterlist
buffers.
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
