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>

2 files changed, 116 insertions, 0 deletions

diff --git a/include/media/davinci/vpfe_types.h b/include/media/davinci/vpfe_types.h
new file mode 100644
index 000000000..e65c9a48d
--- /dev/null
+++ b/include/media/davinci/vpfe_types.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2008-2009 Texas Instruments Inc
+ */
+#ifndef _VPFE_TYPES_H
+#define _VPFE_TYPES_H
+
+#ifdef __KERNEL__
+
+enum vpfe_pin_pol {
+	VPFE_PINPOL_POSITIVE,
+	VPFE_PINPOL_NEGATIVE
+};
+
+enum vpfe_hw_if_type {
+	/* BT656 - 8 bit */
+	VPFE_BT656,
+	/* BT1120 - 16 bit */
+	VPFE_BT1120,
+	/* Raw Bayer */
+	VPFE_RAW_BAYER,
+	/* YCbCr - 8 bit with external sync */
+	VPFE_YCBCR_SYNC_8,
+	/* YCbCr - 16 bit with external sync */
+	VPFE_YCBCR_SYNC_16,
+	/* BT656 - 10 bit */
+	VPFE_BT656_10BIT
+};
+
+/* interface description */
+struct vpfe_hw_if_param {
+	enum vpfe_hw_if_type if_type;
+	enum vpfe_pin_pol hdpol;
+	enum vpfe_pin_pol vdpol;
+};
+
+#endif
+#endif
diff --git a/include/media/davinci/vpif_types.h b/include/media/davinci/vpif_types.h
new file mode 100644
index 000000000..6cce1f09c
--- /dev/null
+++ b/include/media/davinci/vpif_types.h
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2011 Texas Instruments Inc
+ */
+#ifndef _VPIF_TYPES_H
+#define _VPIF_TYPES_H
+
+#include <linux/i2c.h>
+
+#define VPIF_CAPTURE_MAX_CHANNELS	2
+#define VPIF_DISPLAY_MAX_CHANNELS	2
+
+enum vpif_if_type {
+	VPIF_IF_BT656,
+	VPIF_IF_BT1120,
+	VPIF_IF_RAW_BAYER
+};
+
+struct vpif_interface {
+	enum vpif_if_type if_type;
+	unsigned hd_pol:1;
+	unsigned vd_pol:1;
+	unsigned fid_pol:1;
+};
+
+struct vpif_subdev_info {
+	const char *name;
+	struct i2c_board_info board_info;
+};
+
+struct vpif_output {
+	struct v4l2_output output;
+	const char *subdev_name;
+	u32 input_route;
+	u32 output_route;
+};
+
+struct vpif_display_chan_config {
+	const struct vpif_output *outputs;
+	int output_count;
+	bool clip_en;
+};
+
+struct vpif_display_config {
+	int (*set_clock)(int, int);
+	struct vpif_subdev_info *subdevinfo;
+	int subdev_count;
+	int i2c_adapter_id;
+	struct vpif_display_chan_config chan_config[VPIF_DISPLAY_MAX_CHANNELS];
+	const char *card_name;
+};
+
+struct vpif_input {
+	struct v4l2_input input;
+	char *subdev_name;
+	u32 input_route;
+	u32 output_route;
+};
+
+struct vpif_capture_chan_config {
+	struct vpif_interface vpif_if;
+	struct vpif_input *inputs;
+	int input_count;
+};
+
+struct vpif_capture_config {
+	int (*setup_input_channel_mode)(int);
+	int (*setup_input_path)(int, const char *);
+	struct vpif_capture_chan_config chan_config[VPIF_CAPTURE_MAX_CHANNELS];
+	struct vpif_subdev_info *subdev_info;
+	int subdev_count;
+	int i2c_adapter_id;
+	const char *card_name;
+
+	struct v4l2_async_connection *asd[VPIF_CAPTURE_MAX_CHANNELS];
+	int asd_sizes[VPIF_CAPTURE_MAX_CHANNELS];
+};
+#endif /* _VPIF_TYPES_H */