linux-toradex.git/drivers/most, branch v6.19

most: usb: fix double free on late probe failure

2025-11-09T02:15:20+00:00

The MOST subsystem has a non-standard registration function which frees
the interface on registration failures and on deregistration.

This unsurprisingly leads to bugs in the MOST drivers, and a couple of
recent changes turned a reference underflow and use-after-free in the
USB driver into several double free and a use-after-free on late probe
failures.

Fixes: 723de0f9171e ("staging: most: remove device from interface structure")
Fixes: 4b1270902609 ("most: usb: Fix use-after-free in hdm_disconnect")
Fixes: a8cc9e5fcb0e ("most: usb: hdm_probe: Fix calling put_device() before device initialization")
Cc: stable@vger.kernel.org
Cc: Christian Gromm 
Cc: Victoria Votokina 
Signed-off-by: Johan Hovold 
Link: https://patch.msgid.link/20251029093029.28922-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman

most: usb: hdm_probe: Fix calling put_device() before device initialization

2025-10-22T06:04:43+00:00

The early error path in hdm_probe() can jump to err_free_mdev before
&mdev->dev has been initialized with device_initialize(). Calling
put_device(&mdev->dev) there triggers a device core WARN and ends up
invoking kref_put(&kobj->kref, kobject_release) on an uninitialized
kobject.

In this path the private struct was only kmalloc'ed and the intended
release is effectively kfree(mdev) anyway, so free it directly instead
of calling put_device() on an uninitialized device.

This removes the WARNING and fixes the pre-initialization error path.

Fixes: 97a6f772f36b ("drivers: most: add USB adapter driver")
Cc: stable 
Signed-off-by: Victoria Votokina 
Link: https://patch.msgid.link/20251010105241.4087114-3-Victoria.Votokina@kaspersky.com
Signed-off-by: Greg Kroah-Hartman

most: usb: Fix use-after-free in hdm_disconnect

2025-10-22T06:04:39+00:00

hdm_disconnect() calls most_deregister_interface(), which eventually
unregisters the MOST interface device with device_unregister(iface->dev).
If that drops the last reference, the device core may call release_mdev()
immediately while hdm_disconnect() is still executing.

The old code also freed several mdev-owned allocations in
hdm_disconnect() and then performed additional put_device() calls.
Depending on refcount order, this could lead to use-after-free or
double-free when release_mdev() ran (or when unregister paths also
performed puts).

Fix by moving the frees of mdev-owned allocations into release_mdev(),
so they happen exactly once when the device is truly released, and by
dropping the extra put_device() calls in hdm_disconnect() that are
redundant after device_unregister() and most_deregister_interface().

This addresses the KASAN slab-use-after-free reported by syzbot in
hdm_disconnect(). See report and stack traces in the bug link below.

Reported-by: syzbot+916742d5d24f6c254761@syzkaller.appspotmail.com
Cc: stable 
Closes: https://syzkaller.appspot.com/bug?extid=916742d5d24f6c254761
Fixes: 97a6f772f36b ("drivers: most: add USB adapter driver")
Signed-off-by: Victoria Votokina 
Link: https://patch.msgid.link/20251010105241.4087114-2-Victoria.Votokina@kaspersky.com
Signed-off-by: Greg Kroah-Hartman

most: core: Drop device reference after usage in get_channel()

2025-08-19T10:57:34+00:00

In get_channel(), the reference obtained by bus_find_device_by_name()
was dropped via put_device() before accessing the device's driver data
Move put_device() after usage to avoid potential issues.

Fixes: 2485055394be ("staging: most: core: drop device reference")
Cc: stable 
Signed-off-by: Miaoqian Lin 
Link: https://lore.kernel.org/r/20250804082955.3621026-1-linmq006@gmail.com
Signed-off-by: Greg Kroah-Hartman

treewide, timers: Rename from_timer() to timer_container_of()

2025-06-08T07:07:37+00:00

Move this API to the canonical timer_*() namespace.

[ tglx: Redone against pre rc1 ]

Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12+00:00

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar

Merge tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2024-07-25T17:42:22+00:00

Pull driver core updates from Greg KH:
 "Here is the big set of driver core changes for 6.11-rc1.

  Lots of stuff in here, with not a huge diffstat, but apis are evolving
  which required lots of files to be touched. Highlights of the changes
  in here are:

   - platform remove callback api final fixups (Uwe took many releases
     to get here, finally!)

   - Rust bindings for basic firmware apis and initial driver-core
     interactions.

     It's not all that useful for a "write a whole driver in rust" type
     of thing, but the firmware bindings do help out the phy rust
     drivers, and the driver core bindings give a solid base on which
     others can start their work.

     There is still a long way to go here before we have a multitude of
     rust drivers being added, but it's a great first step.

   - driver core const api changes.

     This reached across all bus types, and there are some fix-ups for
     some not-common bus types that linux-next and 0-day testing shook
     out.

     This work is being done to help make the rust bindings more safe,
     as well as the C code, moving toward the end-goal of allowing us to
     put driver structures into read-only memory. We aren't there yet,
     but are getting closer.

   - minor devres cleanups and fixes found by code inspection

   - arch_topology minor changes

   - other minor driver core cleanups

  All of these have been in linux-next for a very long time with no
  reported problems"

* tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
  ARM: sa1100: make match function take a const pointer
  sysfs/cpu: Make crash_hotplug attribute world-readable
  dio: Have dio_bus_match() callback take a const *
  zorro: make match function take a const pointer
  driver core: module: make module_[add|remove]_driver take a const *
  driver core: make driver_find_device() take a const *
  driver core: make driver_[create|remove]_file take a const *
  firmware_loader: fix soundness issue in `request_internal`
  firmware_loader: annotate doctests as `no_run`
  devres: Correct code style for functions that return a pointer type
  devres: Initialize an uninitialized struct member
  devres: Fix memory leakage caused by driver API devm_free_percpu()
  devres: Fix devm_krealloc() wasting memory
  driver core: platform: Switch to use kmemdup_array()
  driver core: have match() callback in struct bus_type take a const *
  MAINTAINERS: add Rust device abstractions to DRIVER CORE
  device: rust: improve safety comments
  MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer
  MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER
  firmware: rust: improve safety comments
  ...

driver core: have match() callback in struct bus_type take a const *

2024-07-03T13:16:54+00:00

In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *.  This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly.  This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki 
Reviewed-by: Alex Elder 
Acked-by: Sumit Garg 
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman

most: remove usage of the deprecated ida_simple_xx() API

2024-06-25T05:25:08+00:00

ida_alloc() and ida_free() should be preferred to the deprecated
ida_simple_get() and ida_simple_remove().

This is less verbose.

Link: https://lkml.kernel.org/r/ddbb2e3f249ba90417dc7ab01713faa1091fb44c.1717855701.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET 
Acked-by: Parthiban Veerasooran 
Cc: Alexey Dobriyan 
Cc: Alistar Popple 
Cc: Christian Gromm 
Cc: Eddie James 
Cc: Jeremy Kerr 
Cc: Joel Stanley 
Cc: Matthew Wilcox (Oracle) 
Signed-off-by: Andrew Morton

most: core: make mostbus const

2024-03-07T20:32:38+00:00

Now that the driver core can properly handle constant struct bus_type,
move the mostbus variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman 
Suggested-by: Greg Kroah-Hartman 
Signed-off-by: "Ricardo B. Marliere" 
Reviewed-by: Greg Kroah-Hartman 
Link: https://lore.kernel.org/r/20240204-bus_cleanup-most-v1-1-f5cd9a06e13f@marliere.net
Signed-off-by: Greg Kroah-Hartman