e60beb95c0
load_unaligned_zeropad() and __get/put_kernel_nofault() functions can read past some buffer limits which may include some MTE granule with a different tag. When MTE async mode is enabled, the load operation crosses the boundaries and the next granule has a different tag the PE sets the TFSR_EL1.TF1 bit as if an asynchronous tag fault is happened. Enable Tag Check Override (TCO) in these functions before the load and disable it afterwards to prevent this to happen. Note: The same condition can be hit in MTE sync mode but we deal with it through the exception handling. In the current implementation, mte_async_mode flag is set only at boot time but in future kasan might acquire some runtime features that that change the mode dynamically, hence we disable it when sync mode is selected for future proof. Cc: Will Deacon <will@kernel.org> Reported-by: Branislav Rankov <Branislav.Rankov@arm.com> Tested-by: Branislav Rankov <Branislav.Rankov@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20210315132019.33202-6-vincenzo.frascino@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> |
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| 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.
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.