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

From: Tom Zanussi
Date: Thu Feb 13 2020 - 17:17:02 EST


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 | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 913760d2d505..d931f1404505 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1885,6 +1885,9 @@ int synth_event_trace(struct trace_event_file *file, unsigned int n_vals, ...)
return ret;
}

+ if (n_vals != state.event->n_fields)
+ return -EINVAL;
+
va_start(args, n_vals);
for (i = 0, n_u64 = 0; i < state.event->n_fields; i++) {
u64 val;
@@ -1960,6 +1963,9 @@ int synth_event_trace_array(struct trace_event_file *file, u64 *vals,
return ret;
}

+ if (n_vals != state.event->n_fields)
+ return -EINVAL;
+
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];
--
2.14.1