linux.git/drivers/base/platform.c, branch v6.12.80

driver core: platform: use generic driver_override infrastructure

2026-04-02T11:09:25+00:00

[ Upstream commit 2b38efc05bf7a8568ec74bfffea0f5cfa62bc01d ]

When a driver is probed through __driver_attach(), the bus' match()
callback is called without the device lock held, thus accessing the
driver_override field without a lock, which can cause a UAF.

Fix this by using the driver-core driver_override infrastructure taking
care of proper locking internally.

Note that calling match() from __driver_attach() without the device lock
held is intentional. [1]

Link: https://lore.kernel.org/driver-core/DGRGTIRHA62X.3RY09D9SOK77P@kernel.org/ [1]
Reported-by: Gui-Dong Han 
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220789
Fixes: 3d713e0e382e ("driver core: platform: add device binding path 'driver_override'")
Reviewed-by: Greg Kroah-Hartman 
Link: https://patch.msgid.link/20260303115720.48783-5-dakr@kernel.org
Signed-off-by: Danilo Krummrich 
Signed-off-by: Sasha Levin

platform: Make platform_bus_type constant

2024-09-03T11:00:50+00:00

Since commit d492cc2573a0 ("driver core: device.h: make struct
bus_type a const *"), the driver core can properly handle constant
struct bus_type, move the platform_bus_type 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: Kunwu Chan 
Link: https://lore.kernel.org/r/20240823075544.144426-1-kunwu.chan@linux.dev
Signed-off-by: Greg Kroah-Hartman

driver core: platform: Switch to use kmemdup_array()

2024-07-04T10:02:38+00:00

Let the kememdup_array() take care about multiplication and possible
overflows.

Signed-off-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20240606164926.3031358-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

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

driver core: platform: fix ups for constant struct device_driver

2024-06-13T14:43:46+00:00

Fix up a few places in the platform core code that can easily handle
struct device_driver being constant.  This is part of the work to make
all struct device_driver pointers be constant.

Cc: Rafael J. Wysocki 
Link: https://lore.kernel.org/r/20240611130103.3262749-8-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman

platform: Make platform_driver::remove() return void

2024-05-27T08:34:35+00:00

struct platform_driver::remove returning an integer made driver authors
expect that returning an error code was proper error handling. However
the driver core ignores the error and continues to remove the device
because there is nothing the core could do anyhow and reentering the
remove callback again is only calling for trouble.

To prevent such wrong assumptions, change the return type of the remove
callback to void. This was prepared by introducing an alternative remove
callback returning void and converting all drivers to that. So .remove()
can be changed without further changes in drivers.

This corresponds to step b) of the plan outlined in commit
5c5a7680e67b ("platform: Provide a remove callback that returns no value").

Signed-off-by: Uwe Kleine-König

driver core: platform: Annotate struct irq_affinity_devres with __counted_by

2023-10-07T16:13:09+00:00

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct
irq_affinity_devres.

Cc: Greg Kroah-Hartman 
Cc: "Rafael J. Wysocki" 
Cc: "Gustavo A. R. Silva" 
Cc: linux-hardening@vger.kernel.org
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook 
Reviewed-by: "Gustavo A. R. Silva" 
Link: https://lore.kernel.org/r/20231006201749.work.432-kees@kernel.org
Signed-off-by: Greg Kroah-Hartman

driver core: platform: Unify the firmware node type check

2023-10-05T09:12:59+00:00

OF and ACPI currently are using asymmetrical APIs to check
for the firmware node type. Unify them by using is_*_node()
against struct fwnode_handle pointer.

Signed-off-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20231003142122.3072824-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

driver core: platform: Use temporary variable in platform_device_add()

2023-10-05T09:12:59+00:00

With the temporary variable for the struct device pointer the code
looks better and slightly easier to read and parse by human being.

Signed-off-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20231003142122.3072824-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

driver core: platform: Refactor error path in a couple places

2023-10-05T09:12:59+00:00

The usual pattern is to bail out on the error case. Besides that
one of the labels is redundant as we may return directly. Refactor
platform_device_add() and platform_dma_configure() accordingly.

Signed-off-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20231003142122.3072824-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman