Commit Graph

1849 Commits

Author SHA1 Message Date
Linus Torvalds
1ec6574a3c Merge tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull kthread updates from Eric Biederman:
 "This updates init and user mode helper tasks to be ordinary user mode
  tasks.

  Commit 40966e316f ("kthread: Ensure struct kthread is present for
  all kthreads") caused init and the user mode helper threads that call
  kernel_execve to have struct kthread allocated for them. This struct
  kthread going away during execve in turned made a use after free of
  struct kthread possible.

  Here, commit 343f4c49f2 ("kthread: Don't allocate kthread_struct for
  init and umh") is enough to fix the use after free and is simple
  enough to be backportable.

  The rest of the changes pass struct kernel_clone_args to clean things
  up and cause the code to make sense.

  In making init and the user mode helpers tasks purely user mode tasks
  I ran into two complications. The function task_tick_numa was
  detecting tasks without an mm by testing for the presence of
  PF_KTHREAD. The initramfs code in populate_initrd_image was using
  flush_delayed_fput to ensuere the closing of all it's file descriptors
  was complete, and flush_delayed_fput does not work in a userspace
  thread.

  I have looked and looked and more complications and in my code review
  I have not found any, and neither has anyone else with the code
  sitting in linux-next"

* tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  sched: Update task_tick_numa to ignore tasks without an mm
  fork: Stop allowing kthreads to call execve
  fork: Explicitly set PF_KTHREAD
  init: Deal with the init process being a user mode process
  fork: Generalize PF_IO_WORKER handling
  fork: Explicity test for idle tasks in copy_thread
  fork: Pass struct kernel_clone_args into copy_thread
  kthread: Don't allocate kthread_struct for init and umh
2022-06-03 16:03:05 -07:00
Linus Torvalds
8eca6b0a64 Merge tag 'pwm/for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding:
 "Quite a large number of conversions this time around, courtesy of Uwe
  who has been working tirelessly on these. No drivers of the legacy API
  are left at this point, so as a next step the old API can be removed.

  Support is added for a few new devices such as the Xilinx AXI timer-
  based PWMs and the PWM IP found on Sunplus SoCs.

  Other than that, there's a number of fixes, cleanups and optimizations"

* tag 'pwm/for-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (43 commits)
  pwm: pwm-cros-ec: Add channel type support
  dt-bindings: google,cros-ec-pwm: Add the new -type compatible
  dt-bindings: Add mfd/cros_ec definitions
  pwm: Document that the pinstate of a disabled PWM isn't reliable
  pwm: twl-led: Implement .apply() callback
  pwm: lpc18xx: Implement .apply() callback
  pwm: mediatek: Implement .apply() callback
  pwm: lpc32xx: Implement .apply() callback
  pwm: tegra: Implement .apply() callback
  pwm: stmpe: Implement .apply() callback
  pwm: sti: Implement .apply() callback
  pwm: pwm-mediatek: Add support for MediaTek Helio X10 MT6795
  dt-bindings: pwm: pwm-mediatek: Add documentation for MT6795 SoC
  pwm: tegra: Optimize period calculation
  pwm: renesas-tpu: Improve precision of period and duty_cycle calculation
  pwm: renesas-tpu: Improve maths to compute register settings
  pwm: renesas-tpu: Rename variables to match the usual naming
  pwm: renesas-tpu: Implement .apply() callback
  pwm: renesas-tpu: Make use of devm functions
  pwm: renesas-tpu: Make use of dev_err_probe()
  ...
2022-06-01 10:49:11 -07:00
Eric W. Biederman
5bd2e97c86 fork: Generalize PF_IO_WORKER handling
Add fn and fn_arg members into struct kernel_clone_args and test for
them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER).
This allows any task that wants to be a user space task that only runs
in kernel mode to use this functionality.

The code on x86 is an exception and still retains a PF_KTHREAD test
because x86 unlikely everything else handles kthreads slightly
differently than user space tasks that start with a function.

The functions that created tasks that start with a function
have been updated to set ".fn" and ".fn_arg" instead of
".stack" and ".stack_size".  These functions are fork_idle(),
create_io_thread(), kernel_thread(), and user_mode_thread().

Link: https://lkml.kernel.org/r/20220506141512.516114-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-05-07 09:01:59 -05:00
Eric W. Biederman
c5febea095 fork: Pass struct kernel_clone_args into copy_thread
With io_uring we have started supporting tasks that are for most
purposes user space tasks that exclusively run code in kernel mode.

The kernel task that exec's init and tasks that exec user mode
helpers are also user mode tasks that just run kernel code
until they call kernel execve.

Pass kernel_clone_args into copy_thread so these oddball
tasks can be supported more cleanly and easily.

v2: Fix spelling of kenrel_clone_args on h8300
Link: https://lkml.kernel.org/r/20220506141512.516114-2-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-05-07 09:01:48 -05:00
Julia Lawall
78b5f52ab6 microblaze: fix typos in comments
Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Link: https://lore.kernel.org/r/20220430191122.8667-1-Julia.Lawall@inria.fr
Signed-off-by: Michal Simek <michal.simek@amd.com>
2022-05-02 08:36:10 +02:00
Sean Anderson
bc1ce713a0 pwm: Add support for Xilinx AXI Timer
This adds PWM support for Xilinx LogiCORE IP AXI soft timers commonly
found on Xilinx FPGAs. At the moment clock control is very basic: we
just enable the clock during probe and pin the frequency. In the future,
someone could add support for disabling the clock when not in use.

Some common code has been specially demarcated. While currently only
used by the PWM driver, it is anticipated that it may be split off in
the future to be used by the timer driver as well.

This driver was written with reference to Xilinx DS764 for v1.03.a [1].

[1] https://www.xilinx.com/support/documentation/ip_documentation/axi_timer/v1_03_a/axi_timer_ds764.pdf

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2022-04-22 18:30:44 +02:00
Michal Simek
68cbfae83a microblaze: Add support for reserved memory defined by DT
In DT reserved memory nodes can be added as is described by
Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
but Microblaze didn't have a support for it. The similar change was done
for ARC by commit 1b10cb21d8 ("ARC: add support for reserved memory
defined by device tree"). It is pretty much enough to call
early_init_fdt_scan_reserved_mem().
Microblaze is not using initial_boot_params that's why there is no need to
call early_init_fdt_reserve_self().

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/da4395776bf0de7207767abcc8a5df05bf411816.1645795048.git.michal.simek@xilinx.com
2022-04-21 10:54:57 +02:00
Michal Simek
e4c70fc695 microblaze: Wire memblock_dump_all()
Wire memblock_dump_all() to be able to see the whole memblock allocation.
Dumps are enabled by passing memblock=debug via kernel command line.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/6f480b6010068872f429df69c8894cc3f1f38f46.1645795048.git.michal.simek@xilinx.com
2022-04-21 10:54:57 +02:00
Michal Simek
61a4e653ca microblaze: Use simple memmove/memcpy implementation from lib/string.c
This is based on previous commit ("microblaze: Use simple memset
implementation from lib/string.c") where generic memset implementation is
used when OPT_LIB_FUNCTION is not defined. The same change can be done for
memset/memcpy implementation where doesn't make sense to have generic
implementation in architecture code.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1f5cfc026a8a458f3e3134ab80f65bd4ac7e3e8e.1645797329.git.michal.simek@xilinx.com
2022-04-21 10:54:21 +02:00
Michal Simek
95fee37be4 microblaze: Do loop unrolling for optimized memset implementation
Align implementation with memcpy and memmove where also remaining bytes are
copied via final switch case instead of using simple implementations which
loop. But this alignment has much stronger reason and definitely aligning
implementation is not the key point here. It is just good to have in mind
that the same technique is used already there.

In GCC 10, now -ftree-loop-distribute-patterns optimization is on at O2.
This optimization causes GCC to convert the while loop in memset.c into a
call to memset.
So this optimization is transforming a loop in a memset/memcpy into a call
to the function itself. This makes the memset implementation as recursive.
"-freestanding" option will disable the built-in library function but it
has been added in generic library implementation.

In default microblaze kernel defconfig we have CONFIG_OPT_LIB_FUNCTION
enabled so it will always pick optimized version of memset which is target
specific so we are replacing the while() loop with switch case to avoid
recursive memset call.

Issue with freestanding was already discussed in connection to commit
33d0f96ffd ("lib/string.c: Use freestanding environment") and also this
is topic in glibc and gcc.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56888
http://patchwork.ozlabs.org/project/glibc/patch/20191121021040.14554-1-sandra@codesourcery.com/

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mahesh Bodapati <mbodapat@xilinx.com>
Link: https://lore.kernel.org/r/10a432e269a6d3349cf458e4f5792522779cba0d.1645797329.git.michal.simek@xilinx.com
2022-04-21 10:54:20 +02:00
Michal Simek
8f0f265e6c microblaze: Use simple memset implementation from lib/string.c
On microblaze systems which are not using OPT_LIB_FUNCTION only simple
memset is used. This function is already implemented in lib/string.c that's
why it should be used instead.
This change is done in respect of issue fixed by commit 33d0f96ffd
("lib/string.c: Use freestanding environment") where gcc-10.x moved
-ftree-loop-distribute-patterns optimization is to O2 optimization level.
This optimization causes GCC to convert the while loop in memset.c into a
call to memset. So This optimization is transforming a loop in a
memset/memcpy into a call to the function itself. This makes the memset
implementation as recursive.

Based on fix above -ffreestanding was used and it needs to be used on
Microblaze too but the patch is not adding this flag it removes simple
implementation to cause that generic implementation is used where this flag
is already setup.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mahesh Bodapati <mbodapat@xilinx.com>
Link: https://lore.kernel.org/r/4a143e7654f72ee893dcea9769946e17d3570b16.1645797329.git.michal.simek@xilinx.com
2022-04-21 10:54:20 +02:00
Linus Torvalds
b8321ed4a4 Merge tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:

 - Add new environment variables, USERCFLAGS and USERLDFLAGS to allow
   additional flags to be passed to user-space programs.

 - Fix missing fflush() bugs in Kconfig and fixdep

 - Fix a minor bug in the comment format of the .config file

 - Make kallsyms ignore llvm's local labels, .L*

 - Fix UAPI compile-test for cross-compiling with Clang

 - Extend the LLVM= syntax to support LLVM=<suffix> form for using a
   particular version of LLVm, and LLVM=<prefix> form for using custom
   LLVM in a particular directory path.

 - Clean up Makefiles

* tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: Make $(LLVM) more flexible
  kbuild: add --target to correctly cross-compile UAPI headers with Clang
  fixdep: use fflush() and ferror() to ensure successful write to files
  arch: syscalls: simplify uapi/kapi directory creation
  usr/include: replace extra-y with always-y
  certs: simplify empty certs creation in certs/Makefile
  certs: include certs/signing_key.x509 unconditionally
  kallsyms: ignore all local labels prefixed by '.L'
  kconfig: fix missing '# end of' for empty menu
  kconfig: add fflush() before ferror() check
  kbuild: replace $(if A,A,B) with $(or A,B)
  kbuild: Add environment variables for userprogs flags
  kbuild: unify cmd_copy and cmd_shipped
2022-03-31 11:59:03 -07:00
Masahiro Yamada
bbc90bc1bd arch: syscalls: simplify uapi/kapi directory creation
$(shell ...) expands to empty. There is no need to assign it to _dummy.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
2022-03-31 12:03:46 +09:00
Linus Torvalds
1930a6e739 Merge tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull ptrace cleanups from Eric Biederman:
 "This set of changes removes tracehook.h, moves modification of all of
  the ptrace fields inside of siglock to remove races, adds a missing
  permission check to ptrace.c

  The removal of tracehook.h is quite significant as it has been a major
  source of confusion in recent years. Much of that confusion was around
  task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the
  semantics clearer).

  For people who don't know tracehook.h is a vestiage of an attempt to
  implement uprobes like functionality that was never fully merged, and
  was later superseeded by uprobes when uprobes was merged. For many
  years now we have been removing what tracehook functionaly a little
  bit at a time. To the point where anything left in tracehook.h was
  some weird strange thing that was difficult to understand"

* tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ptrace: Remove duplicated include in ptrace.c
  ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
  ptrace: Return the signal to continue with from ptrace_stop
  ptrace: Move setting/clearing ptrace_message into ptrace_stop
  tracehook: Remove tracehook.h
  resume_user_mode: Move to resume_user_mode.h
  resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
  signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
  task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
  task_work: Call tracehook_notify_signal from get_signal on all architectures
  task_work: Introduce task_work_pending
  task_work: Remove unnecessary include from posix_timers.h
  ptrace: Remove tracehook_signal_handler
  ptrace: Remove arch_syscall_{enter,exit}_tracehook
  ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
  ptrace/arm: Rename tracehook_report_syscall report_syscall
  ptrace: Move ptrace_report_syscall into ptrace.h
2022-03-28 17:29:53 -07:00
Linus Torvalds
b83d85a5c8 Merge tag 'microblaze-v5.18' of git://git.monstr.eu/linux-2.6-microblaze
Pull microblaze updates from Michal Simek:

 - Small fixups

 - Remove unused pci_phys_mem_access_prot()

* tag 'microblaze-v5.18' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze/PCI: Remove pci_phys_mem_access_prot() dead code
  microblaze: add const to of_device_id
  microblaze: fix typo in a comment
2022-03-28 14:46:53 -07:00
Linus Torvalds
194dfe88d6 Merge tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic updates from Arnd Bergmann:
 "There are three sets of updates for 5.18 in the asm-generic tree:

   - The set_fs()/get_fs() infrastructure gets removed for good.

     This was already gone from all major architectures, but now we can
     finally remove it everywhere, which loses some particularly tricky
     and error-prone code. There is a small merge conflict against a
     parisc cleanup, the solution is to use their new version.

   - The nds32 architecture ends its tenure in the Linux kernel.

     The hardware is still used and the code is in reasonable shape, but
     the mainline port is not actively maintained any more, as all
     remaining users are thought to run vendor kernels that would never
     be updated to a future release.

   - A series from Masahiro Yamada cleans up some of the uapi header
     files to pass the compile-time checks"

* tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (27 commits)
  nds32: Remove the architecture
  uaccess: remove CONFIG_SET_FS
  ia64: remove CONFIG_SET_FS support
  sh: remove CONFIG_SET_FS support
  sparc64: remove CONFIG_SET_FS support
  lib/test_lockup: fix kernel pointer check for separate address spaces
  uaccess: generalize access_ok()
  uaccess: fix type mismatch warnings from access_ok()
  arm64: simplify access_ok()
  m68k: fix access_ok for coldfire
  MIPS: use simpler access_ok()
  MIPS: Handle address errors for accesses above CPU max virtual user address
  uaccess: add generic __{get,put}_kernel_nofault
  nios2: drop access_ok() check from __put_user()
  x86: use more conventional access_ok() definition
  x86: remove __range_not_ok()
  sparc64: add __{get,put}_kernel_nofault()
  nds32: fix access_ok() checks in get/put_user
  uaccess: fix nios2 and microblaze get_user_8()
  sparc64: fix building assembly files
  ...
2022-03-23 18:03:08 -07:00
Linus Torvalds
9030fb0bb9 Merge tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache
Pull folio updates from Matthew Wilcox:

 - Rewrite how munlock works to massively reduce the contention on
   i_mmap_rwsem (Hugh Dickins):

     https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/

 - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph
   Hellwig):

     https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/

 - Convert GUP to use folios and make pincount available for order-1
   pages. (Matthew Wilcox)

 - Convert a few more truncation functions to use folios (Matthew
   Wilcox)

 - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew
   Wilcox)

 - Convert rmap_walk to use folios (Matthew Wilcox)

 - Convert most of shrink_page_list() to use a folio (Matthew Wilcox)

 - Add support for creating large folios in readahead (Matthew Wilcox)

* tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits)
  mm/damon: minor cleanup for damon_pa_young
  selftests/vm/transhuge-stress: Support file-backed PMD folios
  mm/filemap: Support VM_HUGEPAGE for file mappings
  mm/readahead: Switch to page_cache_ra_order
  mm/readahead: Align file mappings for non-DAX
  mm/readahead: Add large folio readahead
  mm: Support arbitrary THP sizes
  mm: Make large folios depend on THP
  mm: Fix READ_ONLY_THP warning
  mm/filemap: Allow large folios to be added to the page cache
  mm: Turn can_split_huge_page() into can_split_folio()
  mm/vmscan: Convert pageout() to take a folio
  mm/vmscan: Turn page_check_references() into folio_check_references()
  mm/vmscan: Account large folios correctly
  mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios
  mm/vmscan: Free non-shmem folios without splitting them
  mm/rmap: Constify the rmap_walk_control argument
  mm/rmap: Convert rmap_walk() to take a folio
  mm: Turn page_anon_vma() into folio_anon_vma()
  mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read()
  ...
2022-03-22 17:03:12 -07:00
Mike Rapoport
7106c51ee9 arch: Add pmd_pfn() where it is missing
We need to use this function in common code, so define it for
architectures and/or configrations that miss it.  The result of
pmd_pfn() will only be used if TRANSPARENT_HUGEPAGE is enabled,
but a function or macro called pmd_pfn() must be defined, even
on machines with two level page tables.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-03-21 12:59:02 -04:00
Eric W. Biederman
03248addad resume_user_mode: Move to resume_user_mode.h
Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h.
While doing that rename tracehook_notify_resume to resume_user_mode_work.

Update all of the places that included tracehook.h for these functions to
include resume_user_mode.h instead.

Update all of the callers of tracehook_notify_resume to call
resume_user_mode_work.

Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-03-10 16:51:50 -06:00
Eric W. Biederman
153474ba1a ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
Rename tracehook_report_syscall_{entry,exit} to
ptrace_report_syscall_{entry,exit} and place them in ptrace.h

There is no longer any generic tracehook infractructure so make
these ptrace specific functions ptrace specific.

Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-03-10 13:35:08 -06:00
Michal Simek
1e364921b0 irqchip/xilinx: Switch to GENERIC_IRQ_MULTI_HANDLER
Register the Xilinx driver as the root interrupt controller using
the GENERIC_IRQ_MULTI_HANDLER API, instead of the arch-specific hack.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Stefan Asserhall <stefan.asserhall@xilinx.com>
[maz: repainted commit message]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/e6c6595a81f662bf839cee3109d0fa58a596ea47.1646380284.git.michal.simek@xilinx.com
2022-03-04 14:32:57 +00:00
Arnd Bergmann
967747bbc0 uaccess: remove CONFIG_SET_FS
There are no remaining callers of set_fs(), so CONFIG_SET_FS
can be removed globally, along with the thread_info field and
any references to it.

This turns access_ok() into a cheaper check against TASK_SIZE_MAX.

As CONFIG_SET_FS is now gone, drop all remaining references to
set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel().

Acked-by: Sam Ravnborg <sam@ravnborg.org> # for sparc32 changes
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Tested-by: Sergey Matyukevich <sergey.matyukevich@synopsys.com> # for arc changes
Acked-by: Stafford Horne <shorne@gmail.com> # [openrisc, asm-generic]
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-25 09:36:06 +01:00
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
Arnd Bergmann
a97b693c37 uaccess: fix nios2 and microblaze get_user_8()
These two architectures implement 8-byte get_user() through
a memcpy() into a four-byte variable, which won't fit.

Use a temporary 64-bit variable instead here, and use a double
cast the way that risc-v and openrisc do to avoid compile-time
warnings.

Fixes: 6a090e9797 ("arch/microblaze: support get_user() of size 8 bytes")
Fixes: 5ccc6af5e8 ("nios2: Memory management")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-25 09:36:00 +01:00
Arnd Bergmann
222ca305c9 uaccess: fix integer overflow on access_ok()
Three architectures check the end of a user access against the
address limit without taking a possible overflow into account.
Passing a negative length or another overflow in here returns
success when it should not.

Use the most common correct implementation here, which optimizes
for a constant 'size' argument, and turns the common case into a
single comparison.

Cc: stable@vger.kernel.org
Fixes: da55128194 ("csky: User access")
Fixes: f663b60f52 ("microblaze: Fix uaccess_ok macro")
Fixes: 7567746e1c ("Hexagon: Add user access functions")
Reported-by: David Laight <David.Laight@aculab.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-14 22:30:53 +01:00