d5ed10bb80
Merge my x86 uaccess updates branch.
The LAM ("Linear Address Masking") updates in this release made me
unhappy about how "access_ok()" was done, and it actually turned out to
have a couple of small bugs in it too. This is my cleanup of the code:
- use the sign bit of the __user pointer rather than masking the
address and checking it against the TASK_SIZE range.
We already did this part for the get/put_user() side, but
'access_ok()' did the naïve "mask and range check" thing, which not
only generates nasty code, but also ended up meaning that __access_ok
itself didn't do a good job, and so copy_from_user_nmi() didn't get
the check right.
- move all the code that is 64-bit only into the 64-bit version of the
header file, so that we don't unnecessarily pollute the shared x86
code and make it look like LAM might work in 32-bit too.
- fix a bug in the address masking (that doesn't end up mattering: in
this case the fix was to just remove the buggy code entirely).
- a couple of trivial cleanups and added commentary about the
access_ok() rules.
* x86-uaccess-cleanup:
x86-64: mm: clarify the 'positive addresses' user address rules
x86: mm: remove 'sign' games from LAM untagged_addr*() macros
x86: uaccess: move 32-bit and 64-bit parts into proper <asm/uaccess_N.h> header
x86: mm: remove architecture-specific 'access_ok()' define
x86-64: make access_ok() independent of LAM
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| 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.