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, 168 insertions, 0 deletions

diff --git a/include/trace/misc/rdma.h b/include/trace/misc/rdma.h
new file mode 100644
index 000000000..81bb454fc
--- /dev/null
+++ b/include/trace/misc/rdma.h
@@ -0,0 +1,168 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2017 Oracle.  All rights reserved.
+ */
+
+/*
+ * enum ib_event_type, from include/rdma/ib_verbs.h
+ */
+#define IB_EVENT_LIST				\
+	ib_event(CQ_ERR)			\
+	ib_event(QP_FATAL)			\
+	ib_event(QP_REQ_ERR)			\
+	ib_event(QP_ACCESS_ERR)			\
+	ib_event(COMM_EST)			\
+	ib_event(SQ_DRAINED)			\
+	ib_event(PATH_MIG)			\
+	ib_event(PATH_MIG_ERR)			\
+	ib_event(DEVICE_FATAL)			\
+	ib_event(PORT_ACTIVE)			\
+	ib_event(PORT_ERR)			\
+	ib_event(LID_CHANGE)			\
+	ib_event(PKEY_CHANGE)			\
+	ib_event(SM_CHANGE)			\
+	ib_event(SRQ_ERR)			\
+	ib_event(SRQ_LIMIT_REACHED)		\
+	ib_event(QP_LAST_WQE_REACHED)		\
+	ib_event(CLIENT_REREGISTER)		\
+	ib_event(GID_CHANGE)			\
+	ib_event_end(WQ_FATAL)
+
+#undef ib_event
+#undef ib_event_end
+
+#define ib_event(x)		TRACE_DEFINE_ENUM(IB_EVENT_##x);
+#define ib_event_end(x)		TRACE_DEFINE_ENUM(IB_EVENT_##x);
+
+IB_EVENT_LIST
+
+#undef ib_event
+#undef ib_event_end
+
+#define ib_event(x)		{ IB_EVENT_##x, #x },
+#define ib_event_end(x)		{ IB_EVENT_##x, #x }
+
+#define rdma_show_ib_event(x) \
+		__print_symbolic(x, IB_EVENT_LIST)
+
+/*
+ * enum ib_wc_status type, from include/rdma/ib_verbs.h
+ */
+#define IB_WC_STATUS_LIST			\
+	ib_wc_status(SUCCESS)			\
+	ib_wc_status(LOC_LEN_ERR)		\
+	ib_wc_status(LOC_QP_OP_ERR)		\
+	ib_wc_status(LOC_EEC_OP_ERR)		\
+	ib_wc_status(LOC_PROT_ERR)		\
+	ib_wc_status(WR_FLUSH_ERR)		\
+	ib_wc_status(MW_BIND_ERR)		\
+	ib_wc_status(BAD_RESP_ERR)		\
+	ib_wc_status(LOC_ACCESS_ERR)		\
+	ib_wc_status(REM_INV_REQ_ERR)		\
+	ib_wc_status(REM_ACCESS_ERR)		\
+	ib_wc_status(REM_OP_ERR)		\
+	ib_wc_status(RETRY_EXC_ERR)		\
+	ib_wc_status(RNR_RETRY_EXC_ERR)		\
+	ib_wc_status(LOC_RDD_VIOL_ERR)		\
+	ib_wc_status(REM_INV_RD_REQ_ERR)	\
+	ib_wc_status(REM_ABORT_ERR)		\
+	ib_wc_status(INV_EECN_ERR)		\
+	ib_wc_status(INV_EEC_STATE_ERR)		\
+	ib_wc_status(FATAL_ERR)			\
+	ib_wc_status(RESP_TIMEOUT_ERR)		\
+	ib_wc_status_end(GENERAL_ERR)
+
+#undef ib_wc_status
+#undef ib_wc_status_end
+
+#define ib_wc_status(x)		TRACE_DEFINE_ENUM(IB_WC_##x);
+#define ib_wc_status_end(x)	TRACE_DEFINE_ENUM(IB_WC_##x);
+
+IB_WC_STATUS_LIST
+
+#undef ib_wc_status
+#undef ib_wc_status_end
+
+#define ib_wc_status(x)		{ IB_WC_##x, #x },
+#define ib_wc_status_end(x)	{ IB_WC_##x, #x }
+
+#define rdma_show_wc_status(x) \
+		__print_symbolic(x, IB_WC_STATUS_LIST)
+
+/*
+ * enum ib_cm_event_type, from include/rdma/ib_cm.h
+ */
+#define IB_CM_EVENT_LIST			\
+	ib_cm_event(REQ_ERROR)			\
+	ib_cm_event(REQ_RECEIVED)		\
+	ib_cm_event(REP_ERROR)			\
+	ib_cm_event(REP_RECEIVED)		\
+	ib_cm_event(RTU_RECEIVED)		\
+	ib_cm_event(USER_ESTABLISHED)		\
+	ib_cm_event(DREQ_ERROR)			\
+	ib_cm_event(DREQ_RECEIVED)		\
+	ib_cm_event(DREP_RECEIVED)		\
+	ib_cm_event(TIMEWAIT_EXIT)		\
+	ib_cm_event(MRA_RECEIVED)		\
+	ib_cm_event(REJ_RECEIVED)		\
+	ib_cm_event(LAP_ERROR)			\
+	ib_cm_event(LAP_RECEIVED)		\
+	ib_cm_event(APR_RECEIVED)		\
+	ib_cm_event(SIDR_REQ_ERROR)		\
+	ib_cm_event(SIDR_REQ_RECEIVED)		\
+	ib_cm_event_end(SIDR_REP_RECEIVED)
+
+#undef ib_cm_event
+#undef ib_cm_event_end
+
+#define ib_cm_event(x)		TRACE_DEFINE_ENUM(IB_CM_##x);
+#define ib_cm_event_end(x)	TRACE_DEFINE_ENUM(IB_CM_##x);
+
+IB_CM_EVENT_LIST
+
+#undef ib_cm_event
+#undef ib_cm_event_end
+
+#define ib_cm_event(x)		{ IB_CM_##x, #x },
+#define ib_cm_event_end(x)	{ IB_CM_##x, #x }
+
+#define rdma_show_ib_cm_event(x) \
+		__print_symbolic(x, IB_CM_EVENT_LIST)
+
+/*
+ * enum rdma_cm_event_type, from include/rdma/rdma_cm.h
+ */
+#define RDMA_CM_EVENT_LIST			\
+	rdma_cm_event(ADDR_RESOLVED)		\
+	rdma_cm_event(ADDR_ERROR)		\
+	rdma_cm_event(ROUTE_RESOLVED)		\
+	rdma_cm_event(ROUTE_ERROR)		\
+	rdma_cm_event(CONNECT_REQUEST)		\
+	rdma_cm_event(CONNECT_RESPONSE)		\
+	rdma_cm_event(CONNECT_ERROR)		\
+	rdma_cm_event(UNREACHABLE)		\
+	rdma_cm_event(REJECTED)			\
+	rdma_cm_event(ESTABLISHED)		\
+	rdma_cm_event(DISCONNECTED)		\
+	rdma_cm_event(DEVICE_REMOVAL)		\
+	rdma_cm_event(MULTICAST_JOIN)		\
+	rdma_cm_event(MULTICAST_ERROR)		\
+	rdma_cm_event(ADDR_CHANGE)		\
+	rdma_cm_event_end(TIMEWAIT_EXIT)
+
+#undef rdma_cm_event
+#undef rdma_cm_event_end
+
+#define rdma_cm_event(x)	TRACE_DEFINE_ENUM(RDMA_CM_EVENT_##x);
+#define rdma_cm_event_end(x)	TRACE_DEFINE_ENUM(RDMA_CM_EVENT_##x);
+
+RDMA_CM_EVENT_LIST
+
+#undef rdma_cm_event
+#undef rdma_cm_event_end
+
+#define rdma_cm_event(x)	{ RDMA_CM_EVENT_##x, #x },
+#define rdma_cm_event_end(x)	{ RDMA_CM_EVENT_##x, #x }
+
+#define rdma_show_cm_event(x) \
+		__print_symbolic(x, RDMA_CM_EVENT_LIST)