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, 48 insertions, 0 deletions

diff --git a/tools/perf/util/intel-pt.h b/tools/perf/util/intel-pt.h
new file mode 100644
index 000000000..18fd0be52
--- /dev/null
+++ b/tools/perf/util/intel-pt.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * intel_pt.h: Intel Processor Trace support
+ * Copyright (c) 2013-2015, Intel Corporation.
+ */
+
+#ifndef INCLUDE__PERF_INTEL_PT_H__
+#define INCLUDE__PERF_INTEL_PT_H__
+
+#define INTEL_PT_PMU_NAME "intel_pt"
+
+enum {
+	INTEL_PT_PMU_TYPE,
+	INTEL_PT_TIME_SHIFT,
+	INTEL_PT_TIME_MULT,
+	INTEL_PT_TIME_ZERO,
+	INTEL_PT_CAP_USER_TIME_ZERO,
+	INTEL_PT_TSC_BIT,
+	INTEL_PT_NORETCOMP_BIT,
+	INTEL_PT_HAVE_SCHED_SWITCH,
+	INTEL_PT_SNAPSHOT_MODE,
+	INTEL_PT_PER_CPU_MMAPS,
+	INTEL_PT_MTC_BIT,
+	INTEL_PT_MTC_FREQ_BITS,
+	INTEL_PT_TSC_CTC_N,
+	INTEL_PT_TSC_CTC_D,
+	INTEL_PT_CYC_BIT,
+	INTEL_PT_MAX_NONTURBO_RATIO,
+	INTEL_PT_FILTER_STR_LEN,
+	INTEL_PT_AUXTRACE_PRIV_MAX,
+};
+
+struct auxtrace_record;
+struct perf_tool;
+union perf_event;
+struct perf_session;
+struct perf_event_attr;
+struct perf_pmu;
+
+struct auxtrace_record *intel_pt_recording_init(int *err);
+
+int intel_pt_process_auxtrace_info(union perf_event *event,
+				   struct perf_session *session);
+
+void intel_pt_pmu_default_config(const struct perf_pmu *intel_pt_pmu,
+				 struct perf_event_attr *attr);
+
+#endif