Arnd reports that with Kees's latest VLA patches applied, the HMAC handling in the QAT driver uses a worst case estimate of 160 bytes for the SHA blocksize, allowing the compiler to determine the size of the stack frame at compile time and throw a warning: drivers/crypto/qat/qat_common/qat_algs.c: In function 'qat_alg_do_precomputes': drivers/crypto/qat/qat_common/qat_algs.c:257:1: error: the frame size of 1112 bytes is larger than 1024 bytes [-Werror=frame-larger-than=] Given that this worst case estimate is only 32 bytes larger than the actual block size of SHA-512, the use of a VLA here was hiding the excessive size of the stack frame from the compiler, and so we should try to move these buffers off the stack. So move the ipad/opad buffers and the various SHA state descriptors into the tfm context struct. Since qat_alg_do_precomputes() is only called in the context of a setkey() operation, this should be safe. Using SHA512_BLOCK_SIZE for the size of the ipad/opad buffers allows them to be used by SHA-1/SHA-256 as well. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.