dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel()grafted

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 <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 119 insertions, 0 deletions

diff --git a/include/dt-bindings/clock/imx7ulp-clock.h b/include/dt-bindings/clock/imx7ulp-clock.h
new file mode 100644
index 000000000..b58370d14
--- /dev/null
+++ b/include/dt-bindings/clock/imx7ulp-clock.h
@@ -0,0 +1,119 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Copyright 2017~2018 NXP
+ *
+ */
+
+#ifndef __DT_BINDINGS_CLOCK_IMX7ULP_H
+#define __DT_BINDINGS_CLOCK_IMX7ULP_H
+
+/* SCG1 */
+
+#define IMX7ULP_CLK_DUMMY		0
+#define IMX7ULP_CLK_ROSC		1
+#define IMX7ULP_CLK_SOSC		2
+#define IMX7ULP_CLK_FIRC		3
+#define IMX7ULP_CLK_SPLL_PRE_SEL	4
+#define IMX7ULP_CLK_SPLL_PRE_DIV	5
+#define IMX7ULP_CLK_SPLL		6
+#define IMX7ULP_CLK_SPLL_POST_DIV1	7
+#define IMX7ULP_CLK_SPLL_POST_DIV2	8
+#define IMX7ULP_CLK_SPLL_PFD0		9
+#define IMX7ULP_CLK_SPLL_PFD1		10
+#define IMX7ULP_CLK_SPLL_PFD2		11
+#define IMX7ULP_CLK_SPLL_PFD3		12
+#define IMX7ULP_CLK_SPLL_PFD_SEL	13
+#define IMX7ULP_CLK_SPLL_SEL		14
+#define IMX7ULP_CLK_APLL_PRE_SEL	15
+#define IMX7ULP_CLK_APLL_PRE_DIV	16
+#define IMX7ULP_CLK_APLL		17
+#define IMX7ULP_CLK_APLL_POST_DIV1	18
+#define IMX7ULP_CLK_APLL_POST_DIV2	19
+#define IMX7ULP_CLK_APLL_PFD0		20
+#define IMX7ULP_CLK_APLL_PFD1		21
+#define IMX7ULP_CLK_APLL_PFD2		22
+#define IMX7ULP_CLK_APLL_PFD3		23
+#define IMX7ULP_CLK_APLL_PFD_SEL	24
+#define IMX7ULP_CLK_APLL_SEL		25
+#define IMX7ULP_CLK_UPLL		26
+#define IMX7ULP_CLK_SYS_SEL		27
+#define IMX7ULP_CLK_CORE_DIV		28
+#define IMX7ULP_CLK_BUS_DIV		29
+#define IMX7ULP_CLK_PLAT_DIV		30
+#define IMX7ULP_CLK_DDR_SEL		31
+#define IMX7ULP_CLK_DDR_DIV		32
+#define IMX7ULP_CLK_NIC_SEL		33
+#define IMX7ULP_CLK_NIC0_DIV		34
+#define IMX7ULP_CLK_GPU_DIV		35
+#define IMX7ULP_CLK_NIC1_DIV		36
+#define IMX7ULP_CLK_NIC1_BUS_DIV	37
+#define IMX7ULP_CLK_NIC1_EXT_DIV	38
+/* IMX7ULP_CLK_MIPI_PLL is unsupported and shouldn't be used in DT */
+#define IMX7ULP_CLK_MIPI_PLL		39
+#define IMX7ULP_CLK_SIRC		40
+#define IMX7ULP_CLK_SOSC_BUS_CLK	41
+#define IMX7ULP_CLK_FIRC_BUS_CLK	42
+#define IMX7ULP_CLK_SPLL_BUS_CLK	43
+#define IMX7ULP_CLK_HSRUN_SYS_SEL	44
+#define IMX7ULP_CLK_HSRUN_CORE_DIV	45
+
+#define IMX7ULP_CLK_CORE		46
+#define IMX7ULP_CLK_HSRUN_CORE		47
+
+#define IMX7ULP_CLK_SCG1_END		48
+
+/* PCC2 */
+#define IMX7ULP_CLK_DMA1		0
+#define IMX7ULP_CLK_RGPIO2P1		1
+#define IMX7ULP_CLK_FLEXBUS		2
+#define IMX7ULP_CLK_SEMA42_1		3
+#define IMX7ULP_CLK_DMA_MUX1		4
+#define IMX7ULP_CLK_CAAM		6
+#define IMX7ULP_CLK_LPTPM4		7
+#define IMX7ULP_CLK_LPTPM5		8
+#define IMX7ULP_CLK_LPIT1		9
+#define IMX7ULP_CLK_LPSPI2		10
+#define IMX7ULP_CLK_LPSPI3		11
+#define IMX7ULP_CLK_LPI2C4		12
+#define IMX7ULP_CLK_LPI2C5		13
+#define IMX7ULP_CLK_LPUART4		14
+#define IMX7ULP_CLK_LPUART5		15
+#define IMX7ULP_CLK_FLEXIO1		16
+#define IMX7ULP_CLK_USB0		17
+#define IMX7ULP_CLK_USB1		18
+#define IMX7ULP_CLK_USB_PHY		19
+#define IMX7ULP_CLK_USB_PL301		20
+#define IMX7ULP_CLK_USDHC0		21
+#define IMX7ULP_CLK_USDHC1		22
+#define IMX7ULP_CLK_WDG1		23
+#define IMX7ULP_CLK_WDG2		24
+
+#define IMX7ULP_CLK_PCC2_END		25
+
+/* PCC3 */
+#define IMX7ULP_CLK_LPTPM6		0
+#define IMX7ULP_CLK_LPTPM7		1
+#define IMX7ULP_CLK_LPI2C6		2
+#define IMX7ULP_CLK_LPI2C7		3
+#define IMX7ULP_CLK_LPUART6		4
+#define IMX7ULP_CLK_LPUART7		5
+#define IMX7ULP_CLK_VIU			6
+#define IMX7ULP_CLK_DSI			7
+#define IMX7ULP_CLK_LCDIF		8
+#define IMX7ULP_CLK_MMDC		9
+#define IMX7ULP_CLK_PCTLC		10
+#define IMX7ULP_CLK_PCTLD		11
+#define IMX7ULP_CLK_PCTLE		12
+#define IMX7ULP_CLK_PCTLF		13
+#define IMX7ULP_CLK_GPU3D		14
+#define IMX7ULP_CLK_GPU2D		15
+
+#define IMX7ULP_CLK_PCC3_END		16
+
+/* SMC1 */
+#define IMX7ULP_CLK_ARM			0
+
+#define IMX7ULP_CLK_SMC1_END		1
+
+#endif /* __DT_BINDINGS_CLOCK_IMX7ULP_H */