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 --- .../devicetree/bindings/pps/pps-gpio.yaml | 49 ++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 Documentation/devicetree/bindings/pps/pps-gpio.yaml (limited to 'Documentation/devicetree/bindings/pps') diff --git a/Documentation/devicetree/bindings/pps/pps-gpio.yaml b/Documentation/devicetree/bindings/pps/pps-gpio.yaml new file mode 100644 index 000000000..383a83874 --- /dev/null +++ b/Documentation/devicetree/bindings/pps/pps-gpio.yaml @@ -0,0 +1,49 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pps/pps-gpio.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: PPS Signal via GPIO + +maintainers: + - Fabio Estevam + +properties: + compatible: + const: pps-gpio + + gpios: + description: The GPIO that provides the PPS signal. + maxItems: 1 + + echo-gpios: + description: The GPIO that provides the PPS ECHO signal. + maxItems: 1 + + echo-active-ms: + description: Duration in ms of the active portion of the echo pulse. + + assert-falling-edge: + description: Indicates a falling edge assert, when present. Rising edge if absent. + type: boolean + +required: + - compatible + - gpios + +additionalProperties: false + +examples: + - | + #include + + pps { + compatible = "pps-gpio"; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_pps>; + gpios = <&gpio1 26 GPIO_ACTIVE_HIGH>; + assert-falling-edge; + echo-gpios = <&gpio1 27 GPIO_ACTIVE_HIGH>; + echo-active-ms = <100>; + }; -- cgit v1.3.1