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 --- drivers/usb/image/microtek.h | 55 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 drivers/usb/image/microtek.h (limited to 'drivers/usb/image/microtek.h') diff --git a/drivers/usb/image/microtek.h b/drivers/usb/image/microtek.h new file mode 100644 index 000000000..7bd5f4639 --- /dev/null +++ b/drivers/usb/image/microtek.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + /* + * Driver for Microtek Scanmaker X6 USB scanner and possibly others. + * + * (C) Copyright 2000 John Fremlin + * (C) Copyright 2000 Oliver Neukum + * + * See microtek.c for history + * + */ + +typedef void (*mts_scsi_cmnd_callback)(struct scsi_cmnd *); + + +struct mts_transfer_context +{ + struct mts_desc *instance; + mts_scsi_cmnd_callback final_callback; + struct scsi_cmnd *srb; + + void *data; + unsigned data_length; + int data_pipe; + struct scatterlist *curr_sg; + + u8 *scsi_status; /* status returned from ep_response after command completion */ +}; + + +struct mts_desc { + struct mts_desc *next; + struct mts_desc *prev; + + struct usb_device *usb_dev; + struct usb_interface *usb_intf; + + /* Endpoint addresses */ + u8 ep_out; + u8 ep_response; + u8 ep_image; + + struct Scsi_Host *host; + + struct urb *urb; + struct mts_transfer_context context; +}; + + +#define MTS_EP_OUT 0x1 +#define MTS_EP_RESPONSE 0x2 +#define MTS_EP_IMAGE 0x3 +#define MTS_EP_TOTAL 0x3 + +#define MTS_SCSI_ERR_MASK ~0x3fu + -- cgit v1.3.1