[for-next][PATCH 07/12] tracing: Check that the synthetic event and field names are legal

[Steven Rostedt]

From: Tom Zanussi <zanussi@xxxxxxxxxx>

Call the is_good_name() function used by probe events to make sure
synthetic event and field names don't contain illegal characters and
cause unexpected parsing of synthetic event commands.

Link: https://lkml.kernel.org/r/c4d4bb59d3ac39bcbd70fba0cf837d6b1cedb015.1602598160.git.zanussi@xxxxxxxxxx

Fixes: 4b147936fa50 (tracing: Add support for 'synthetic' events)
Reported-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Reviewed-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Tested-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Tom Zanussi <zanussi@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
 kernel/trace/trace_events_synth.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index b19e2f4159ab..8c9d6e464da0 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -572,6 +572,10 @@ static struct synth_field *parse_synth_field(int argc, const char **argv,
 		ret = -ENOMEM;
 		goto free;
 	}
+	if (!is_good_name(field->name)) {
+		ret = -EINVAL;
+		goto free;
+	}
 
 	if (field_type[0] == ';')
 		field_type++;
@@ -1112,6 +1116,11 @@ static int __create_synth_event(int argc, const char *name, const char **argv)
 
 	mutex_lock(&event_mutex);
 
+	if (!is_good_name(name)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	event = find_synth_event(name);
 	if (event) {
 		ret = -EEXIST;
-- 
2.28.0