174 Commits
Author SHA1 Message Date
Ian AbbottandGreg Kroah-Hartman 8e6b36f434 comedi: amplc_dio200: Add sanity checks for I/O base address
The "amplc_dio200" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a supported
board (PC212E, PC214E, PC215E, PC218E, or PC272E).  It currently allows
any base address to be configured but the hardware only supports base
addresses (set by on-board DIP switches) in the range 0 to 0xFE0 on
32-byte boundaries.  (Technically, the DIP switches allow 16-byte
boundaries, but I do not think that is advisable given that the boards
decode a 32-byte address range.)

Add a sanity check to ensure the device is not configured at an
unsupported base address.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-7-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 15:49:36 +02:00
Ian AbbottandGreg Kroah-Hartman 81c2e0c8b7 comedi: aio_iiro_16: Add sanity checks for I/O base address
The "aio_iiro_16" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a supported
board (IIRO-16).  It currently allows any base address to be configured
but the hardware only supports base addresses (set by on-board jumpers)
in the range 0x100 to 0x3F8 on 8-byte boundaries.

Add a sanity check to ensure the device is not configured at an
unsupported base address.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-6-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 15:49:36 +02:00
Ian AbbottandGreg Kroah-Hartman 254ae67d39 comedi: aio_aio12_8: Add sanity checks for I/O base address
The "aio_aio12_8" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of a supported
board (AIO12-8, AI12-8, or AO12-4).  It currently allows any base
address to be configured but the hardware only supports base addresses
(set by on-board jumpers) in the range 0x100 to 0x3C0 on 32-byte
boundaries.

Add a sanity check to ensure the device is not configured at an
unsupported base address.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-5-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 15:49:36 +02:00
Ian AbbottandGreg Kroah-Hartman a02b67b23e comedi: adq12b: Add sanity checks for I/O base address
The "adq12b" driver uses an admin-supplied configuration option
(`it->options[0]`) to configure the I/O port base address of the ADQ12-B
board.  It currently allows any base address to be configured but the
hardware only supports the following base addresses (set by an on-board
jumper): 0x300, 0x320, 0x340, 0x360, 0x380, 0x3A0.

Add a sanity check to ensure the device is not configured at an
unsupported base address.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-4-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 15:49:36 +02:00
Ian AbbottandGreg Kroah-Hartman cb51837eee comedi: 8255: Add some I/O base address sanity checks
The "8255" driver allows a COMEDI device to be constructed from one or
more 8255 chips, each at an I/O port base address specified by the
admin-supplied configuration options (`it->options[]`).  Currently, the
driver allows any I/O base addresses to be specified as long as the I/O
regions can be reserved, and it converts the specified `int` option
values holding the base address to `unsigned long`.

It doesn't make sense to allow base addresses that are not aligned to
4-byte boundaries because the hardware register addresses would not be
decoded properly, so add a check for valid alignment.

Convert the option values that specify the base addresses from `int` to
`unsigned int` instead of `unsigned long` so they end up the same on
32-bit and 64-bit systems.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-3-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 15:49:36 +02:00
Ian AbbottandGreg Kroah-Hartman 241cb8dee0 comedi: add comedi_check_request_region()
There is an existing comedi_request_region(dev, start, len) function
used by COMEDI drivers for legacy devices to request an I/O port region
starting at a specified base address (which must be non-zero) and with a
specified length.  It uses request_region().  On success, it sets
dev->iobase and dev->iolen and returns 0.  There is a alternative
function __comedi_request_region(dev, start, len) which does the same
thing without setting dev->iobase and dev->iolen.

Most hardware devices have restrictions on the allowed I/O port base
address and alignment, so add new functions
comedi_check_request_region(dev, start, len, minstart, maxend, minalign)
and __comedi_check_request_region(dev, start, len, minstart, maxend,
minalign) to perform these additional checks.  Turn the original
functions into static inline wrapper functions that call the new
functions.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-2-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 15:49:36 +02:00
Deepanshu KartikeyandGreg Kroah-Hartman 93853512f5 comedi: dt2815: add hardware detection to prevent crash
The dt2815 driver crashes when attached to I/O ports without actual
hardware present. This occurs because syzkaller or users can attach
the driver to arbitrary I/O addresses via COMEDI_DEVCONFIG ioctl.

When no hardware exists at the specified port, inb() operations return
0xff (floating bus), but outb() operations can trigger page faults due
to undefined behavior, especially under race conditions:

  BUG: unable to handle page fault for address: 000000007fffff90
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  RIP: 0010:dt2815_attach+0x6e0/0x1110

Add hardware detection by reading the status register before attempting
any write operations. If the read returns 0xff, assume no hardware is
present and fail the attach with -ENODEV. This prevents crashes from
outb() operations on non-existent hardware.

Reported-by: syzbot+72f94b474d6e50b71ffc@syzkaller.appspotmail.com
Cc: stable <stable@kernel.org>
Closes: https://syzkaller.appspot.com/bug?extid=72f94b474d6e50b71ffc
Tested-by: syzbot+72f94b474d6e50b71ffc@syzkaller.appspotmail.com
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
Link: [https://lore.kernel.org/all/20260126070458.10974-1-kartikey406@gmail.com/T/]
Link: [https://lore.kernel.org/all/20260126070458.10974-1-kartikey406@gmail.com/T/
Link: https://patch.msgid.link/20260309104859.503529-1-kartikey406@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 14:40:27 +02:00
Edward Adam DavisandGreg Kroah-Hartman 29f644f14b comedi: runflags cannot determine whether to reclaim chanlist
syzbot reported a memory leak [1], because commit 4e1da516de ("comedi:
Add reference counting for Comedi command handling") did not consider
the exceptional exit case in do_cmd_ioctl() where runflags is not set.
This caused chanlist not to be properly freed by do_become_nonbusy(),
as it only frees chanlist when runflags is correctly set.

Added a check in do_become_nonbusy() for the case where runflags is not
set, to properly free the chanlist memory.

[1]
BUG: memory leak
  backtrace (crc 844a0efa):
    __comedi_get_user_chanlist drivers/comedi/comedi_fops.c:1815 [inline]
    do_cmd_ioctl.part.0+0x112/0x350 drivers/comedi/comedi_fops.c:1890
    do_cmd_ioctl drivers/comedi/comedi_fops.c:1858 [inline]

Fixes: 4e1da516de ("comedi: Add reference counting for Comedi command handling")
Reported-by: syzbot+f238baf6ded841b5a82e@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=f238baf6ded841b5a82e
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Cc: stable <stable@kernel.org> # 6.19
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260310111104.70959-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 14:39:58 +02:00
Ian AbbottandGreg Kroah-Hartman 4b9a9a6d71 comedi: Reinit dev->spinlock between attachments to low-level drivers
`struct comedi_device` is the main controlling structure for a COMEDI
device created by the COMEDI subsystem.  It contains a member `spinlock`
containing a spin-lock that is initialized by the COMEDI subsystem, but
is reserved for use by a low-level driver attached to the COMEDI device
(at least since commit 25436dc9d8 ("Staging: comedi: remove RT
code")).

Some COMEDI devices (those created on initialization of the COMEDI
subsystem when the "comedi.comedi_num_legacy_minors" parameter is
non-zero) can be attached to different low-level drivers over their
lifetime using the `COMEDI_DEVCONFIG` ioctl command.  This can result in
inconsistent lock states being reported when there is a mismatch in the
spin-lock locking levels used by each low-level driver to which the
COMEDI device has been attached.  Fix it by reinitializing
`dev->spinlock` before calling the low-level driver's `attach` function
pointer if `CONFIG_LOCKDEP` is enabled.

Reported-by: syzbot+cc9f7f4a7df09f53c4a4@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=cc9f7f4a7df09f53c4a4
Fixes: ed9eccbe89 ("Staging: add comedi core")
Cc: stable <stable@kernel.org>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260225132427.86578-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 14:39:39 +02:00
Ian AbbottandGreg Kroah-Hartman cc797d4821 comedi: me_daq: Fix potential overrun of firmware buffer
`me2600_xilinx_download()` loads the firmware that was requested by
`request_firmware()`.  It is possible for it to overrun the source
buffer because it blindly trusts the file format.  It reads a data
stream length from the first 4 bytes into variable `file_length` and
reads the data stream contents of length `file_length` from offset 16
onwards.  Although it checks that the supplied firmware is at least 16
bytes long, it does not check that it is long enough to contain the data
stream.

Add a test to ensure that the supplied firmware is long enough to
contain the header and the data stream.  On failure, log an error and
return `-EINVAL`.

Fixes: 85acac6109 ("Staging: comedi: add me_daq driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260205140130.76697-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 14:39:29 +02:00
Ian AbbottandGreg Kroah-Hartman 3fb43a7a5b comedi: me4000: Fix potential overrun of firmware buffer
`me4000_xilinx_download()` loads the firmware that was requested by
`request_firmware()`.  It is possible for it to overrun the source
buffer because it blindly trusts the file format.  It reads a data
stream length from the first 4 bytes into variable `file_length` and
reads the data stream contents of length `file_length` from offset 16
onwards.

Add a test to ensure that the supplied firmware is long enough to
contain the header and the data stream.  On failure, log an error and
return `-EINVAL`.

Note: The firmware loading was totally broken before commit ac584af599
("staging: comedi: me4000: fix firmware downloading"), but that is the
most sensible target for this fix.

Fixes: ac584af599 ("staging: comedi: me4000: fix firmware downloading")
Cc: stable <stable@kernel.org>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260205133949.71722-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 14:39:21 +02:00
Ian AbbottandGreg Kroah-Hartman 101ab946b7 comedi: ni_atmio16d: Fix invalid clean-up after failed attach
If the driver's COMEDI "attach" handler function (`atmio16d_attach()`)
returns an error, the COMEDI core will call the driver's "detach"
handler function (`atmio16d_detach()`) to clean up.  This calls
`reset_atmio16d()` unconditionally, but depending on where the error
occurred in the attach handler, the device may not have been
sufficiently initialized to call `reset_atmio16d()`.  It uses
`dev->iobase` as the I/O port base address and `dev->private` as the
pointer to the COMEDI device's private data structure.  `dev->iobase`
may still be set to its initial value of 0, which would result in
undesired writes to low I/O port addresses.  `dev->private` may still be
`NULL`, which would result in null pointer dereferences.

Fix `atmio16d_detach()` by checking that `dev->private` is valid
(non-null) before calling `reset_atmio16d()`.  This implies that
`dev->iobase` was set correctly since that is set up before
`dev->private`.

Fixes: 2323b27630 ("Staging: comedi: add ni_at_atmio16d driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260128150011.5006-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-02 14:38:28 +02:00
Kees CookandLinus Torvalds 189f164e57 Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses
Conversion performed via this Coccinelle script:

  // SPDX-License-Identifier: GPL-2.0-only
  // Options: --include-headers-for-types --all-includes --include-headers --keep-comments
  virtual patch

  @gfp depends on patch && !(file in "tools") && !(file in "samples")@
  identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex,
 		    kzalloc_obj,kzalloc_objs,kzalloc_flex,
		    kvmalloc_obj,kvmalloc_objs,kvmalloc_flex,
		    kvzalloc_obj,kvzalloc_objs,kvzalloc_flex};
  @@

  	ALLOC(...
  -		, GFP_KERNEL
  	)

  $ make coccicheck MODE=patch COCCI=gfp.cocci

Build and boot tested x86_64 with Fedora 42's GCC and Clang:

Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01

Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-22 08:26:33 -08:00
Linus Torvalds 32a92f8c89 Convert more 'alloc_obj' cases to default GFP_KERNEL arguments
This converts some of the visually simpler cases that have been split
over multiple lines.  I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.

Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script.  I probably had made it a bit _too_ trivial.

So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.

The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 20:03:00 -08:00
Linus Torvalds bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook 69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Linus Torvalds 505d195b0f Merge tag 'char-misc-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc/IIO driver updates from Greg KH:
 "Here is the big set of char/misc/iio and other smaller driver
  subsystem changes for 7.0-rc1. Lots of little things in here,
  including:

   - Loads of iio driver changes and updates and additions

   - gpib driver updates

   - interconnect driver updates

   - i3c driver updates

   - hwtracing (coresight and intel) driver updates

   - deletion of the obsolete mwave driver

   - binder driver updates (rust and c versions)

   - mhi driver updates (causing a merge conflict, see below)

   - mei driver updates

   - fsi driver updates

   - eeprom driver updates

   - lots of other small char and misc driver updates and cleanups

  All of these have been in linux-next for a while, with no reported
  issues"

* tag 'char-misc-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (297 commits)
  mux: mmio: fix regmap leak on probe failure
  rust_binder: return p from rust_binder_transaction_target_node()
  drivers: android: binder: Update ARef imports from sync::aref
  rust_binder: fix needless borrow in context.rs
  iio: magn: mmc5633: Fix Kconfig for combination of I3C as module and driver builtin
  iio: sca3000: Fix a resource leak in sca3000_probe()
  iio: proximity: rfd77402: Add interrupt handling support
  iio: proximity: rfd77402: Document device private data structure
  iio: proximity: rfd77402: Use devm-managed mutex initialization
  iio: proximity: rfd77402: Use kernel helper for result polling
  iio: proximity: rfd77402: Align polling timeout with datasheet
  iio: cros_ec: Allow enabling/disabling calibration mode
  iio: frequency: ad9523: correct kernel-doc bad line warning
  iio: buffer: buffer_impl.h: fix kernel-doc warnings
  iio: gyro: itg3200: Fix unchecked return value in read_raw
  MAINTAINERS: add entry for ADE9000 driver
  iio: accel: sca3000: remove unused last_timestamp field
  iio: accel: adxl372: remove unused int2_bitmask field
  iio: adc: ad7766: Use iio_trigger_generic_data_rdy_poll()
  iio: magnetometer: Remove IRQF_ONESHOT
  ...
2026-02-17 09:11:04 -08:00
Linus Torvalds 136114e0ab Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:

 - "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves
   disk space by teaching ocfs2 to reclaim suballocator block group
   space (Heming Zhao)

 - "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the
   ARRAY_END() macro and uses it in various places (Alejandro Colomar)

 - "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes
   the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the
   page size (Pnina Feder)

 - "kallsyms: Prevent invalid access when showing module buildid" cleans
   up kallsyms code related to module buildid and fixes an invalid
   access crash when printing backtraces (Petr Mladek)

 - "Address page fault in ima_restore_measurement_list()" fixes a
   kexec-related crash that can occur when booting the second-stage
   kernel on x86 (Harshit Mogalapalli)

 - "kho: ABI headers and Documentation updates" updates the kexec
   handover ABI documentation (Mike Rapoport)

 - "Align atomic storage" adds the __aligned attribute to atomic_t and
   atomic64_t definitions to get natural alignment of both types on
   csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain)

 - "kho: clean up page initialization logic" simplifies the page
   initialization logic in kho_restore_page() (Pratyush Yadav)

 - "Unload linux/kernel.h" moves several things out of kernel.h and into
   more appropriate places (Yury Norov)

 - "don't abuse task_struct.group_leader" removes the usage of
   ->group_leader when it is "obviously unnecessary" (Oleg Nesterov)

 - "list private v2 & luo flb" adds some infrastructure improvements to
   the live update orchestrator (Pasha Tatashin)

* tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits)
  watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency
  procfs: fix missing RCU protection when reading real_parent in do_task_stat()
  watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()
  kcsan, compiler_types: avoid duplicate type issues in BPF Type Format
  kho: fix doc for kho_restore_pages()
  tests/liveupdate: add in-kernel liveupdate test
  liveupdate: luo_flb: introduce File-Lifecycle-Bound global state
  liveupdate: luo_file: Use private list
  list: add kunit test for private list primitives
  list: add primitives for private list manipulations
  delayacct: fix uapi timespec64 definition
  panic: add panic_force_cpu= parameter to redirect panic to a specific CPU
  netclassid: use thread_group_leader(p) in update_classid_task()
  RDMA/umem: don't abuse current->group_leader
  drm/pan*: don't abuse current->group_leader
  drm/amd: kill the outdated "Only the pthreads threading model is supported" checks
  drm/amdgpu: don't abuse current->group_leader
  android/binder: use same_thread_group(proc->tsk, current) in binder_mmap()
  android/binder: don't abuse current->group_leader
  kho: skip memoryless NUMA nodes when reserving scratch areas
  ...
2026-02-12 12:13:01 -08:00
Greg Kroah-Hartman dbd91d4f55 Merge 6.19-rc7 into char-misc-next
We need the char/misc/iio fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-26 12:04:04 +01:00
Randy DunlapandAndrew Morton 24c776355f kernel.h: drop hex.h and update all hex.h users
Remove <linux/hex.h> from <linux/kernel.h> and update all users/callers of
hex.h interfaces to directly #include <linux/hex.h> as part of the process
of putting kernel.h on a diet.

Removing hex.h from kernel.h means that 36K C source files don't have to
pay the price of parsing hex.h for the roughly 120 C source files that
need it.

This change has been build-tested with allmodconfig on most ARCHes.  Also,
all users/callers of <linux/hex.h> in the entire source tree have been
updated if needed (if not already #included).

Link: https://lkml.kernel.org/r/20251215005206.2362276-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20 19:44:19 -08:00
Ian AbbottandGreg Kroah-Hartman e03b29b55f comedi: dmm32at: serialize use of paged registers
Some of the hardware registers of the DMM-32-AT board are multiplexed,
using the least significant two bits of the Miscellaneous Control
register to select the function of registers at offsets 12 to 15:

 00 => 8254 timer/counter registers are accessible
 01 => 8255 digital I/O registers are accessible
 10 => Reserved
 11 => Calibration registers are accessible

The interrupt service routine (`dmm32at_isr()`) clobbers the bottom two
bits of the register with value 00, which would interfere with access to
the 8255 registers by the `dm32at_8255_io()` function (used for Comedi
instruction handling on the digital I/O subdevice).

Make use of the generic Comedi device spin-lock `dev->spinlock` (which
is otherwise unused by this driver) to serialize access to the
miscellaneous control register and paged registers.

Fixes: 3c501880ac ("Staging: comedi: add dmm32at driver")
Cc: stable@vger.kernel.org
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260112162835.91688-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-16 16:43:51 +01:00
Ian AbbottandGreg Kroah-Hartman 10d28cffb3 comedi: Fix getting range information for subdevices 16 to 255
The `COMEDI_RANGEINFO` ioctl does not work properly for subdevice
indices above 15.  Currently, the only in-tree COMEDI drivers that
support more than 16 subdevices are the "8255" driver and the
"comedi_bond" driver.  Making the ioctl work for subdevice indices up to
255 is achievable.  It needs minor changes to the handling of the
`COMEDI_RANGEINFO` and `COMEDI_CHANINFO` ioctls that should be mostly
harmless to user-space, apart from making them less broken.  Details
follow...

The `COMEDI_RANGEINFO` ioctl command gets the list of supported ranges
(usually with units of volts or milliamps) for a COMEDI subdevice or
channel.  (Only some subdevices have per-channel range tables, indicated
by the `SDF_RANGETYPE` flag in the subdevice information.)  It uses a
`range_type` value and a user-space pointer, both supplied by
user-space, but the `range_type` value should match what was obtained
using the `COMEDI_CHANINFO` ioctl (if the subdevice has per-channel
range tables)  or `COMEDI_SUBDINFO` ioctl (if the subdevice uses a
single range table for all channels).  Bits 15 to 0 of the `range_type`
value contain the length of the range table, which is the only part that
user-space should care about (so it can use a suitably sized buffer to
fetch the range table).  Bits 23 to 16 store the channel index, which is
assumed to be no more than 255 if the subdevice has per-channel range
tables, and is set to 0 if the subdevice has a single range table.  For
`range_type` values produced by the `COMEDI_SUBDINFO` ioctl, bits 31 to
24 contain the subdevice index, which is assumed to be no more than 255.
But for `range_type` values produced by the `COMEDI_CHANINFO` ioctl,
bits 27 to 24 contain the subdevice index, which is assumed to be no
more than 15, and bits 31 to 28 contain the COMEDI device's minor device
number for some unknown reason lost in the mists of time.  The
`COMEDI_RANGEINFO` ioctl extract the length from bits 15 to 0 of the
user-supplied `range_type` value, extracts the channel index from bits
23 to 16 (only used if the subdevice has per-channel range tables),
extracts the subdevice index from bits 27 to 24, and ignores bits 31 to
28.  So for subdevice indices 16 to 255, the `COMEDI_SUBDINFO` or
`COMEDI_CHANINFO` ioctl will report a `range_type` value that doesn't
work with the `COMEDI_RANGEINFO` ioctl.  It will either get the range
table for the subdevice index modulo 16, or will fail with `-EINVAL`.

To fix this, always use bits 31 to 24 of the `range_type` value to hold
the subdevice index (assumed to be no more than 255).  This affects the
`COMEDI_CHANINFO` and `COMEDI_RANGEINFO` ioctls.  There should not be
anything in user-space that depends on the old, broken usage, although
it may now see different values in bits 31 to 28 of the `range_type`
values reported by the `COMEDI_CHANINFO` ioctl for subdevices that have
per-channel subdevices.  User-space should not be trying to decode bits
31 to 16 of the `range_type` values anyway.

Fixes: ed9eccbe89 ("Staging: add comedi core")
Cc: stable@vger.kernel.org #5.17+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20251203162438.176841-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-16 16:42:15 +01:00
Ian AbbottandGreg Kroah-Hartman b842f8c639 comedi: comedi_test: add a DIO subdevice
The fake "comedi_test" device currently has two subdevices: an analog
input subdevice, and an analog output subdevice.  To make it a bit more
useful for testing, add a third subdevice for digital I/O.

The new DIO subdevice has 32 channels with each channel individually
programmable as an input or an output.  To add a bit of interaction,
channels 0 to 15 are wired to channels 16 to 31 (0 to 16, 1 to 17,
etc.), and the state of each wire can be read back on both of the
channels connected to it.  The outputs are modelled as NPN open
collector outputs with a pull-up resistor on the wire, so the state of
each wire (and the value read back from each channel connected to it)
will be logic level 1 unless either channel is configured as an output
at logic level 0.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20251210124455.69131-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-16 16:33:13 +01:00
Ian AbbottandGreg Kroah-Hartman d63cf1eea1 comedi: don't use mutex for COMEDI_BUFINFO ioctl
The main mutex in a comedi device can get held for quite a while when
processing comedi instructions, so for performance reasons, the "read",
"write", and "poll" file operations do not use it; they use the
`attach_lock` rwsemaphore to protect against the comedi device becoming
detached at an inopportune moment.  As an alternative to using the
"read" and "write" operations, user-space can mmap the data buffer and
use the `COMEDI_BUFINFO` ioctl to manage data transfer through the
buffer.  However, the "ioctl" file handler currently locks the main
mutex for all ioctl commands.  Make the handling of the `COMEDI_BUFINFO`
an exception, using the `attach_lock` rwsemaphore during normal
operation.  However, before it calls `do_become_nonbusy()` at the end of
acquisition, it does need to lock the main mutex, but it needs to unlock
the `attach_lock` rwsemaphore first to avoid deadlock.  After locking
the main mutex, it needs to check that it is still in a suitable state
to become non-busy, because things may have changed while unlocked.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20251205131332.16672-1-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-16 16:33:08 +01:00
Linus Torvalds 83bd89291f Merge tag 'char-misc-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc/IIO driver updates from Greg KH:
 "Here is the big set of char/misc/iio driver updates for 6.19-rc1. Lots
  of stuff in here including:

   - lots of IIO driver updates, cleanups, and additions

   - large interconnect driver changes as they get converted over to a
     dynamic system of ids

   - coresight driver updates

   - mwave driver updates

   - binder driver updates and changes

   - comedi driver fixes now that the fuzzers are being set loose on
     them

   - nvmem driver updates

   - new uio driver addition

   - lots of other small char/misc driver updates, full details in the
     shortlog

  All of these have been in linux-next for a while now"

* tag 'char-misc-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (304 commits)
  char: applicom: fix NULL pointer dereference in ac_ioctl
  hangcheck-timer: fix coding style spacing
  hangcheck-timer: Replace %Ld with %lld
  hangcheck-timer: replace printk(KERN_CRIT) with pr_crit
  uio: Add SVA support for PCI devices via uio_pci_generic_sva.c
  dt-bindings: slimbus: fix warning from example
  intel_th: Fix error handling in intel_th_output_open
  misc: rp1: Fix an error handling path in rp1_probe()
  char: xillybus: add WQ_UNBOUND to alloc_workqueue users
  misc: bh1770glc: use pm_runtime_resume_and_get() in power_state_store
  misc: cb710: Fix a NULL vs IS_ERR() check in probe()
  mux: mmio: Add suspend and resume support
  virt: acrn: split acrn_mmio_dev_res out of acrn_mmiodev
  greybus: gb-beagleplay: Fix timeout handling in bootloader functions
  greybus: add WQ_PERCPU to alloc_workqueue users
  char/mwave: drop typedefs
  char/mwave: drop printk wrapper
  char/mwave: remove printk tracing
  char/mwave: remove unneeded fops
  char/mwave: remove MWAVE_FUTZ_WITH_OTHER_DEVICES ifdeffery
  ...
2025-12-06 18:34:24 -08:00