From 7ab215f22d04067094de8c81c20ba4c565ff8dd4 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu <mhiramat@kernel.org> Date: Mon, 17 Feb 2020 18:52:39 +0900 Subject: [PATCH] tracing: Clear trace_state when starting trace Clear trace_state data structure when starting trace in __synth_event_trace_start() internal function. Currently trace_state is initialized only in the synth_event_trace_start() API, but the trace_state in synth_event_trace() and synth_event_trace_array() are on the stack without initialization. This means those APIs will see wrong parameters and wil skip closing process in __synth_event_trace_end() because trace_state->disabled may be !0. Link: http://lkml.kernel.org/r/158193315899.8868.1781259176894639952.stgit@devnote2 Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> --- kernel/trace/trace_events_hist.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index f068d55bd37f..9d87aa1f0b79 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1824,6 +1824,8 @@ __synth_event_trace_start(struct trace_event_file *file, int entry_size, fields_size = 0; int ret = 0; + memset(trace_state, '\0', sizeof(*trace_state)); + /* * Normal event tracing doesn't get called at all unless the * ENABLED bit is set (which attaches the probe thus allowing @@ -2063,8 +2065,6 @@ int synth_event_trace_start(struct trace_event_file *file, if (!trace_state) return -EINVAL; - memset(trace_state, '\0', sizeof(*trace_state)); - ret = __synth_event_trace_start(file, trace_state); if (ret == -ENOENT) ret = 0; /* just disabled, not really an error */