linux-stable/arch/x86
Arnd Bergmann 12700c17fc uaccess: generalize access_ok()
There are many different ways that access_ok() is defined across
architectures, but in the end, they all just compare against the
user_addr_max() value or they accept anything.

Provide one definition that works for most architectures, checking
against TASK_SIZE_MAX for user processes or skipping the check inside
of uaccess_kernel() sections.

For architectures without CONFIG_SET_FS(), this should be the fastest
check, as it comes down to a single comparison of a pointer against a
compile-time constant, while the architecture specific versions tend to
do something more complex for historic reasons or get something wrong.

Type checking for __user annotations is handled inconsistently across
architectures, but this is easily simplified as well by using an inline
function that takes a 'const void __user *' argument. A handful of
callers need an extra __user annotation for this.

Some architectures had trick to use 33-bit or 65-bit arithmetic on the
addresses to calculate the overflow, however this simpler version uses
fewer registers, which means it can produce better object code in the
end despite needing a second (statically predicted) branch.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64, asm-generic]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Stafford Horne <shorne@gmail.com>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-25 09:36:05 +01:00
..
boot Kbuild updates for v5.17 2022-01-19 11:15:19 +02:00
configs x86/kbuild: Enable CONFIG_KALLSYMS_ALL=y in the defconfigs 2022-01-08 22:55:29 +01:00
crypto lib/crypto: blake2s: avoid indirect calls to compression function for Clang CFI 2022-02-04 19:22:32 +01:00
entry Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2022-01-17 05:49:30 +02:00
events x86: remove __range_not_ok() 2022-02-25 09:36:05 +01:00
hyperv hyperv-next for 5.17 2022-01-16 15:53:00 +02:00
ia32 audit/stable-5.16 PR 20211101 2021-11-01 21:17:39 -07:00
include uaccess: generalize access_ok() 2022-02-25 09:36:05 +01:00
kernel x86: remove __range_not_ok() 2022-02-25 09:36:05 +01:00
kvm KVM/arm64 fixes for 5.17, take #2 2022-02-05 00:58:25 -05:00
lib x86: remove __range_not_ok() 2022-02-25 09:36:05 +01:00
math-emu x86: Prepare asm files for straight-line-speculation 2021-12-08 12:25:37 +01:00
mm Merge branch 'akpm' (patches from Andrew) 2022-01-15 20:37:06 +02:00
net - Get rid of all the .fixup sections because this generates 2022-01-12 16:31:19 -08:00
pci PCI/sysfs: Find shadow ROM before static attribute initialization 2022-01-26 10:41:21 -06:00
platform - Get rid of all the .fixup sections because this generates 2022-01-12 16:31:19 -08:00
power x86: Prepare asm files for straight-line-speculation 2021-12-08 12:25:37 +01:00
purgatory x86/purgatory: Remove -nostdlib compiler flag 2021-12-30 14:13:06 +01:00
ras
realmode - Flush *all* mappings from the TLB after switching to the trampoline 2022-01-10 09:51:38 -08:00
tools x86/build: Use the proper name CONFIG_FW_LOADER 2021-12-29 22:20:38 +01:00
um bitmap patches for 5.17-rc1 2022-01-23 06:20:44 +02:00
video
xen x86/Xen: streamline (and fix) PV CPU enumeration 2022-02-03 08:25:04 +01:00
.gitignore
Kbuild kbuild: use more subdir- for visiting subdirectories while cleaning 2021-10-24 13:49:46 +09:00
Kconfig ftrace: Have architectures opt-in for mcount build time sorting 2022-01-27 19:15:44 -05:00
Kconfig.assembler
Kconfig.cpu x86/mmx_32: Remove X86_USE_3DNOW 2021-12-11 09:09:45 +01:00
Kconfig.debug
Makefile x86: Add straight-line-speculation mitigation 2021-12-09 13:32:25 +01:00
Makefile.um
Makefile_32.cpu