[PATCH v2 3/4] tracing: Check that number of vals matches number of synth event fields

[Tom Zanussi]

Commit 7276531d4036('tracing: Consolidate trace() functions')
inadvertently dropped the synth_event_trace() and
synth_event_trace_array() checks that verify the number of values
passed in matches the number of fields in the synthetic event being
traced, so add them back.

Signed-off-by: Tom Zanussi <zanussi@xxxxxxxxxx>
---
 kernel/trace/trace_events_hist.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 913760d2d505..95d4c871f87b 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1885,6 +1885,11 @@ int synth_event_trace(struct trace_event_file *file, unsigned int n_vals, ...)
 		return ret;
 	}
 
+	if (n_vals != state.event->n_fields) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	va_start(args, n_vals);
 	for (i = 0, n_u64 = 0; i < state.event->n_fields; i++) {
 		u64 val;
@@ -1921,7 +1926,7 @@ int synth_event_trace(struct trace_event_file *file, unsigned int n_vals, ...)
 		}
 	}
 	va_end(args);
-
+out:
 	__synth_event_trace_end(&state);
 
 	return ret;
@@ -1960,6 +1965,11 @@ int synth_event_trace_array(struct trace_event_file *file, u64 *vals,
 		return ret;
 	}
 
+	if (n_vals != state.event->n_fields) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	for (i = 0, n_u64 = 0; i < state.event->n_fields; i++) {
 		if (state.event->fields[i]->is_string) {
 			char *str_val = (char *)(long)vals[i];
@@ -1991,7 +2001,7 @@ int synth_event_trace_array(struct trace_event_file *file, u64 *vals,
 			n_u64++;
 		}
 	}
-
+out:
 	__synth_event_trace_end(&state);
 
 	return ret;
-- 
2.14.1