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, 58 insertions, 0 deletions

diff --git a/include/dt-bindings/clock/aspeed-clock.h b/include/dt-bindings/clock/aspeed-clock.h
new file mode 100644
index 000000000..671e5a476
--- /dev/null
+++ b/include/dt-bindings/clock/aspeed-clock.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
+
+#ifndef DT_BINDINGS_ASPEED_CLOCK_H
+#define DT_BINDINGS_ASPEED_CLOCK_H
+
+#define ASPEED_CLK_GATE_ECLK		0
+#define ASPEED_CLK_GATE_GCLK		1
+#define ASPEED_CLK_GATE_MCLK		2
+#define ASPEED_CLK_GATE_VCLK		3
+#define ASPEED_CLK_GATE_BCLK		4
+#define ASPEED_CLK_GATE_DCLK		5
+#define ASPEED_CLK_GATE_REFCLK		6
+#define ASPEED_CLK_GATE_USBPORT2CLK	7
+#define ASPEED_CLK_GATE_LCLK		8
+#define ASPEED_CLK_GATE_USBUHCICLK	9
+#define ASPEED_CLK_GATE_D1CLK		10
+#define ASPEED_CLK_GATE_YCLK		11
+#define ASPEED_CLK_GATE_USBPORT1CLK	12
+#define ASPEED_CLK_GATE_UART1CLK	13
+#define ASPEED_CLK_GATE_UART2CLK	14
+#define ASPEED_CLK_GATE_UART5CLK	15
+#define ASPEED_CLK_GATE_ESPICLK		16
+#define ASPEED_CLK_GATE_MAC1CLK		17
+#define ASPEED_CLK_GATE_MAC2CLK		18
+#define ASPEED_CLK_GATE_RSACLK		19
+#define ASPEED_CLK_GATE_UART3CLK	20
+#define ASPEED_CLK_GATE_UART4CLK	21
+#define ASPEED_CLK_GATE_SDCLK		22
+#define ASPEED_CLK_GATE_LHCCLK		23
+#define ASPEED_CLK_HPLL			24
+#define ASPEED_CLK_AHB			25
+#define ASPEED_CLK_APB			26
+#define ASPEED_CLK_UART			27
+#define ASPEED_CLK_SDIO			28
+#define ASPEED_CLK_ECLK			29
+#define ASPEED_CLK_ECLK_MUX		30
+#define ASPEED_CLK_LHCLK		31
+#define ASPEED_CLK_MAC			32
+#define ASPEED_CLK_BCLK			33
+#define ASPEED_CLK_MPLL			34
+#define ASPEED_CLK_24M			35
+#define ASPEED_CLK_MAC1RCLK		36
+#define ASPEED_CLK_MAC2RCLK		37
+
+#define ASPEED_RESET_XDMA		0
+#define ASPEED_RESET_MCTP		1
+#define ASPEED_RESET_ADC		2
+#define ASPEED_RESET_JTAG_MASTER	3
+#define ASPEED_RESET_MIC		4
+#define ASPEED_RESET_PWM		5
+#define ASPEED_RESET_PECI		6
+#define ASPEED_RESET_I2C		7
+#define ASPEED_RESET_AHB		8
+#define ASPEED_RESET_CRT1		9
+#define ASPEED_RESET_HACE		10
+#define ASPEED_RESET_VIDEO		11
+
+#endif