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/base/trace.h | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 drivers/base/trace.h (limited to 'drivers/base/trace.h') diff --git a/drivers/base/trace.h b/drivers/base/trace.h new file mode 100644 index 000000000..3b83b13a5 --- /dev/null +++ b/drivers/base/trace.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Device core Trace Support + * Copyright (C) 2021, Intel Corporation + * + * Author: Andy Shevchenko + */ + +#undef TRACE_SYSTEM +#define TRACE_SYSTEM dev + +#if !defined(__DEV_TRACE_H) || defined(TRACE_HEADER_MULTI_READ) +#define __DEV_TRACE_H + +#include +#include +#include + +DECLARE_EVENT_CLASS(devres, + TP_PROTO(struct device *dev, const char *op, void *node, const char *name, size_t size), + TP_ARGS(dev, op, node, name, size), + TP_STRUCT__entry( + __string(devname, dev_name(dev)) + __field(struct device *, dev) + __field(const char *, op) + __field(void *, node) + __string(name, name) + __field(size_t, size) + ), + TP_fast_assign( + __assign_str(devname); + __entry->op = op; + __entry->node = node; + __assign_str(name); + __entry->size = size; + ), + TP_printk("%s %3s %p %s (%zu bytes)", __get_str(devname), + __entry->op, __entry->node, __get_str(name), __entry->size) +); + +DEFINE_EVENT(devres, devres_log, + TP_PROTO(struct device *dev, const char *op, void *node, const char *name, size_t size), + TP_ARGS(dev, op, node, name, size) +); + +#endif /* __DEV_TRACE_H */ + +/* this part has to be here */ + +#undef TRACE_INCLUDE_PATH +#define TRACE_INCLUDE_PATH . + +#undef TRACE_INCLUDE_FILE +#define TRACE_INCLUDE_FILE trace + +#include -- cgit v1.3.1