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 --- include/uapi/fwctl/pds.h | 62 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 include/uapi/fwctl/pds.h (limited to 'include/uapi/fwctl/pds.h') diff --git a/include/uapi/fwctl/pds.h b/include/uapi/fwctl/pds.h new file mode 100644 index 000000000..66be32411 --- /dev/null +++ b/include/uapi/fwctl/pds.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* Copyright(c) Advanced Micro Devices, Inc */ + +/* + * fwctl interface info for pds_fwctl + */ + +#ifndef _UAPI_FWCTL_PDS_H_ +#define _UAPI_FWCTL_PDS_H_ + +#include + +/** + * struct fwctl_info_pds + * @uctx_caps: bitmap of firmware capabilities + * + * Return basic information about the FW interface available. + */ +struct fwctl_info_pds { + __u32 uctx_caps; +}; + +/** + * enum pds_fwctl_capabilities + * @PDS_FWCTL_QUERY_CAP: firmware can be queried for information + * @PDS_FWCTL_SEND_CAP: firmware can be sent commands + */ +enum pds_fwctl_capabilities { + PDS_FWCTL_QUERY_CAP = 0, + PDS_FWCTL_SEND_CAP, +}; + +/** + * struct fwctl_rpc_pds + * @in.op: requested operation code + * @in.ep: firmware endpoint to operate on + * @in.rsvd: reserved + * @in.len: length of payload data + * @in.payload: address of payload buffer + * @in: rpc in parameters + * @out.retval: operation result value + * @out.rsvd: reserved + * @out.len: length of result data buffer + * @out.payload: address of payload data buffer + * @out: rpc out parameters + */ +struct fwctl_rpc_pds { + struct { + __u32 op; + __u32 ep; + __u32 rsvd; + __u32 len; + __aligned_u64 payload; + } in; + struct { + __u32 retval; + __u32 rsvd[2]; + __u32 len; + __aligned_u64 payload; + } out; +}; +#endif /* _UAPI_FWCTL_PDS_H_ */ -- cgit v1.3.1