From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- .../access-controllers/access-controllers.yaml | 84 ++++++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 Documentation/devicetree/bindings/access-controllers/access-controllers.yaml (limited to 'Documentation/devicetree/bindings/access-controllers') diff --git a/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml b/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml new file mode 100644 index 000000000..99e2865f0 --- /dev/null +++ b/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml @@ -0,0 +1,84 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/access-controllers/access-controllers.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic Domain Access Controllers + +maintainers: + - Oleksii Moisieiev + +description: |+ + Common access controllers properties + + Access controllers are in charge of stating which of the hardware blocks under + their responsibility (their domain) can be accesssed by which compartment. A + compartment can be a cluster of CPUs (or coprocessors), a range of addresses + or a group of hardware blocks. An access controller's domain is the set of + resources covered by the access controller. + + This device tree binding can be used to bind devices to their access + controller provided by access-controllers property. In this case, the device + is a consumer and the access controller is the provider. + + An access controller can be represented by any node in the device tree and + can provide one or more configuration parameters, needed to control parameters + of the consumer device. A consumer node can refer to the provider by phandle + and a set of phandle arguments, specified by '#access-controller-cells' + property in the access controller node. + + Access controllers are typically used to set/read the permissions of a + hardware block and grant access to it. Any of which depends on the access + controller. The capabilities of each access controller are defined by the + binding of the access controller device. + + Each node can be a consumer for the several access controllers. + +# always select the core schema +select: true + +properties: + "#access-controller-cells": + description: + Number of cells in an access-controllers specifier; + Can be any value as specified by device tree binding documentation + of a particular provider. The node is an access controller. + + access-controller-names: + $ref: /schemas/types.yaml#/definitions/string-array + description: + A list of access-controllers names, sorted in the same order as + access-controllers entries. Consumer drivers will use + access-controller-names to match with existing access-controllers entries. + + access-controllers: + $ref: /schemas/types.yaml#/definitions/phandle-array + description: + A list of access controller specifiers, as defined by the + bindings of the access-controllers provider. + +additionalProperties: true + +examples: + - | + clock_controller: access-controllers@50000 { + reg = <0x50000 0x400>; + #access-controller-cells = <2>; + }; + + bus_controller: bus@60000 { + reg = <0x60000 0x10000>; + #address-cells = <1>; + #size-cells = <1>; + ranges; + #access-controller-cells = <3>; + + uart4: serial@60100 { + reg = <0x60100 0x400>; + clocks = <&clk_serial>; + access-controllers = <&clock_controller 1 2>, + <&bus_controller 1 3 5>; + access-controller-names = "clock", "bus"; + }; + }; -- cgit v1.3.1