Linux kernel modifications for the Kernel Hacking exam
e7b159a48b
For TLS device offload the tag/message authentication code are filled in by the device. The kernel merely reserves space for them. Because device overwrites it, the contents of the tag make do no matter. Current code tries to save space by reusing the header as the tag. This, however, leads to an additional frag being created and defeats buffer coalescing (which trickles all the way down to the drivers). Remove this optimization, and try to allocate the space for the tag in the usual way, leave the memory uninitialized. If memory allocation fails rewind the record pointer so that we use the already copied user data as tag. Note that the optimization was actually buggy, as the tag for TLS 1.2 is 16 bytes, but header is just 13, so the reuse may had looked past the end of the page.. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| 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 | ||
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.
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.