From 259eb72da21b36d356efb23c4187589089cf443f Mon Sep 17 00:00:00 2001
From: Jiaolong He <hejiaolong@kernelsoft.com>
Date: Wed, 12 Jul 2023 16:06:25 +0800
Subject: [PATCH] ipc/mqueue: add tracepoints for message load and store

This patch adds tracepoints to load_msg and store_msg, which would helps
if any message get lost or corrupted when traversing through kernel.

Signed-off-by: Jiaolong He <hejiaolong@kernelsoft.com>
---
 include/trace/events/mq.h | 46 +++++++++++++++++++++++++++++++++++++++
 ipc/msgutil.c             | 11 ++++++++--
 2 files changed, 55 insertions(+), 2 deletions(-)
 create mode 100644 include/trace/events/mq.h

diff --git a/include/trace/events/mq.h b/include/trace/events/mq.h
new file mode 100644
index 000000000000..954cb343c915
--- /dev/null
+++ b/include/trace/events/mq.h
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM mq
+
+#if !defined(_TRACE_MQ_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_MQ_H
+
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(mq,
+
+	TP_PROTO(struct msg_msg *msg, size_t mlen),
+
+	TP_ARGS(msg, mlen),
+
+	TP_STRUCT__entry(
+		__field(struct msg_msg *, msg)
+		__field(size_t, mlen)
+	),
+
+	TP_fast_assign(
+		__entry->msg = msg;
+		__entry->mlen = mlen;
+	),
+
+	TP_printk("msg=%p len=%zu", __entry->msg, __entry->mlen)
+);
+
+DEFINE_EVENT(mq, load_msg,
+
+	TP_PROTO(struct msg_msg *msg, size_t mlen),
+
+	TP_ARGS(msg, mlen)
+);
+
+DEFINE_EVENT(mq, store_msg,
+
+	TP_PROTO(struct msg_msg *msg, size_t mlen),
+
+	TP_ARGS(msg, mlen)
+);
+
+#endif /* _TRACE_MQ_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/ipc/msgutil.c b/ipc/msgutil.c
index 5b52d1dc7a8d..6a954b155f16 100644
--- a/ipc/msgutil.c
+++ b/ipc/msgutil.c
@@ -18,6 +18,9 @@
 
 #include "util.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/mq.h>
+
 DEFINE_SPINLOCK(mq_lock);
 
 /*
@@ -83,11 +86,12 @@ out_err:
 	return NULL;
 }
 
-struct msg_msg *load_msg(const void __user *src, size_t len)
+struct msg_msg *load_msg(const void __user *src, size_t mlen)
 {
 	struct msg_msg *msg;
 	struct msg_msgseg *seg;
 	int err = -EFAULT;
+	size_t len = mlen;
 	size_t alen;
 
 	msg = alloc_msg(len);
@@ -110,6 +114,7 @@ struct msg_msg *load_msg(const void __user *src, size_t len)
 	if (err)
 		goto out_err;
 
+	trace_load_msg(msg, mlen);
 	return msg;
 
 out_err:
@@ -149,11 +154,13 @@ struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst)
 	return ERR_PTR(-ENOSYS);
 }
 #endif
-int store_msg(void __user *dest, struct msg_msg *msg, size_t len)
+int store_msg(void __user *dest, struct msg_msg *msg, size_t mlen)
 {
 	size_t alen;
+	size_t len = mlen;
 	struct msg_msgseg *seg;
 
+	trace_store_msg(msg, mlen);
 	alen = min(len, DATALEN_MSG);
 	if (copy_to_user(dest, msg + 1, alen))
 		return -1;