Signed-off-by: Seokwoo Chung (Ryan) <redacted>
---
 kernel/trace/trace.c        |  4 +--
 kernel/trace/trace_fprobe.c | 49 ++++++++++++++++++++-----------------
 kernel/trace/trace_probe.h  |  2 ++
 3 files changed, 31 insertions(+), 24 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 10cdcc7b194e..73b59d47dfe7 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c

@@ -5578,8 +5578,8 @@ static const char readme_msg[] =
 	"\t           r[maxactive][:[<group>/][<event>]] <place> [<args>]\n"
 #endif
 #ifdef CONFIG_FPROBE_EVENTS
-	"\t           f[:[<group>/][<event>]] <func-name>[:entry|:exit] [<args>]\n"
-	"\t		(single symbols still accept %return)\n"
+	"\t           f[:[<group>/][<event>]] <func-name>[%return] [<args>]\n"
+	"\t	      f[:[<group>/][<event>]] <func-list>[:entry|:exit] [<args>]\n" 
 	"\t           t[:[<group>/][<event>]] <tracepoint> [<args>]\n"
 #endif
 #ifdef CONFIG_HIST_TRIGGERS

diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c
index 5a2a41eea603..1663c341ddb4 100644
--- a/kernel/trace/trace_fprobe.c
+++ b/kernel/trace/trace_fprobe.c

@@ -187,16 +187,23 @@ DEFINE_FREE(tuser_put, struct tracepoint_user *,
  */
 struct trace_fprobe {
 	struct dyn_event	devent;
-	char			*filter;
+
 	struct fprobe		fp;
-	bool			list_mode;
-	char			*nofilter;
 	const char		*symbol;
-	struct trace_probe	tp;
+	char			*filter;
+	char			*nofilter;
+
 	bool			tprobe;
 	struct tracepoint_user	*tuser;
+
+	struct trace_probe tp;

 };
 
+static inline bool trace_fprobe_has_list(const struct trace_fprobe *tf)
+{
+	return tf->filter || tf->nofilter;
+}
+
 static bool is_trace_fprobe(struct dyn_event *ev)
 {
 	return ev->ops == &trace_fprobe_ops;

@@ -847,7 +854,7 @@ static int __register_trace_fprobe(struct trace_fprobe *tf)
 	 * - list_mode: pass filter/nofilter
 	 * - single: pass symbol only (legacy)
 	 */
-	if (tf->list_mode)
+	if (trace_fprobe_has_list(tf))
 		return register_fprobe(&tf->fp, tf->filter, tf->nofilter);
 	return register_fprobe(&tf->fp, tf->symbol, NULL);
 }

@@ -1188,11 +1195,18 @@ static int parse_fprobe_spec(const char *in, bool is_tracepoint,
 	*base = NULL; *filter = NULL; *nofilter = NULL;
 	*is_return = false; *list_mode = false;
 
-	if (is_tracepoint) {
+	if (is_tracepoint) 
+	{
 		if (strchr(in, ',') || strchr(in, ':'))
+		{
+			trace_probe_log_err(0, BAD_TP_NAME);
 			return -EINVAL;
+		}
 		if (strstr(in, "%return"))
+		{
+			trace_probe_log_err(p - in, BAD_TP_NAME);
 			return -EINVAL;
+		}
 		for (p = in; *p; p++)
 			if (!isalnum(*p) && *p != '_')
 				return -EINVAL;

@@ -1225,6 +1239,7 @@ static int parse_fprobe_spec(const char *in, bool is_tracepoint,
 			} else if (!strcmp(p, ":entry")) {
 				*(char *)p = '\0';
 			} else {
+				trace_probe_log_err(p - work, BAD_LIST_SUFFIX);
 				return -EINVAL;
 			}
 		}

@@ -1233,6 +1248,7 @@ static int parse_fprobe_spec(const char *in, bool is_tracepoint,
 	list = !!strchr(work, ',');
 	
 	if (list && legacy_ret) {
+		trace_probe_log_err(p - work, BAD_LEGACY_RET);
 		return -EINVAL;
 	}
 

@@ -1245,12 +1261,9 @@ static int parse_fprobe_spec(const char *in, bool is_tracepoint,
 
 	if (list) {
 		char *tmp = b, *tok;
-		size_t fsz, nfsz;
 
-		fsz = nfsz = strlen(b) + 1;
-
-		f = kzalloc(fsz, GFP_KERNEL);
-		nf = kzalloc(nfsz, GFP_KERNEL);
+		f = kzalloc(strlen(b) + 1, GFP_KERNEL);
+		nf = kzalloc(strlen(b) + 1, GFP_KERNEL);
 		if (!f || !nf)
 			return -ENOMEM;
 

@@ -1261,6 +1274,7 @@ static int parse_fprobe_spec(const char *in, bool is_tracepoint,
 			if (*tok == '\0') {
 				trace_probe_log_err(tmp - b - 1, BAD_TP_NAME);
 				return -EINVAL;
+			}
 
 			if (neg)
 				tok++;

@@ -1455,17 +1469,8 @@ static int trace_fprobe_create_internal(int argc, const char *argv[],
 
 	/* carry list parsing result into tf */
 	if (!is_tracepoint) {
-		tf->list_mode = list_mode;
-		if (parsed_filter) {
-			tf->filter = kstrdup(parsed_filter, GFP_KERNEL);
-			if (!tf->filter)
-				return -ENOMEM;
-		}
-		if (parsed_nofilter) {
-			tf->nofilter = kstrdup(parsed_nofilter, GFP_KERNEL);
-			if (!tf->nofilter)
-				return -ENOMEM;
-		}
+		tf->filter = no_free_ptr(parsed_filter);
+		tf->nofilter = no_free_ptr(parsed_nofilter);
 	}
 
 	/* parse arguments */

diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 9fc56c937130..b8b0544eb7cd 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h

@@ -494,9 +494,11 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
 	C(BAD_PROBE_ADDR,	"Invalid probed address or symbol"),	\
 	C(NON_UNIQ_SYMBOL,	"The symbol is not unique"),		\
 	C(BAD_RETPROBE,		"Retprobe address must be an function entry"), \
+	C(BAD_LEGACY_RET,	"Legacy %return not allowed with list"), \
 	C(NO_TRACEPOINT,	"Tracepoint is not found"),		\
 	C(BAD_TP_NAME,		"Invalid character in tracepoint name"),\
 	C(BAD_ADDR_SUFFIX,	"Invalid probed address suffix"), \
+	C(BAD_LIST_SUFFIX,	"Bad list suffix"), \
 	C(NO_GROUP_NAME,	"Group name is not specified"),		\
 	C(GROUP_TOO_LONG,	"Group name is too long"),		\
 	C(BAD_GROUP_NAME,	"Group name must follow the same rules as C identifiers"), \