[for-linus][PATCH 03/15] tracing: Check that number of vals matches number of synth event fields

From: Steven Rostedt
Date: Mon Feb 24 2020 - 12:23:09 EST


From: Tom Zanussi <zanussi@xxxxxxxxxx>

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.

Link: http://lkml.kernel.org/r/32819cac708714693669e0dfe10fe9d935e94a16.1581720155.git.zanussi@xxxxxxxxxx

Signed-off-by: Tom Zanussi <zanussi@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
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 6a380fb83864..45622194a34d 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1878,6 +1878,11 @@ 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;
@@ -1914,7 +1919,7 @@ int synth_event_trace(struct trace_event_file *file, unsigned int n_vals, ...)
}
}
va_end(args);
-
+out:
__synth_event_trace_end(&state);

return ret;
@@ -1953,6 +1958,11 @@ 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];
@@ -1984,7 +1994,7 @@ int synth_event_trace_array(struct trace_event_file *file, u64 *vals,
n_u64++;
}
}
-
+out:
__synth_event_trace_end(&state);

return ret;
--
2.25.0