[PATCH v4 09/11] tracing: Replace strncpy() with __get_task_comm()

[Yafang Shao]

Using __get_task_comm() to read the task comm ensures that the name is
always NUL-terminated, regardless of the source string. This approach also
facilitates future extensions to the task comm.

Signed-off-by: Yafang Shao <laoar.shao at gmail.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat at kernel.org>
Cc: Steven Rostedt <rostedt at goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
---
 kernel/trace/trace.c             | 2 +-
 kernel/trace/trace_events_hist.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 578a49ff5c32..ce94a86154a2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1907,7 +1907,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
 	max_data->critical_start = data->critical_start;
 	max_data->critical_end = data->critical_end;
 
-	strncpy(max_data->comm, tsk->comm, TASK_COMM_LEN);
+	__get_task_comm(max_data->comm, TASK_COMM_LEN, tsk);
 	max_data->pid = tsk->pid;
 	/*
 	 * If tsk == current, then use current_uid(), as that does not use
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 6ece1308d36a..721d4758a79f 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1599,7 +1599,7 @@ static inline void save_comm(char *comm, struct task_struct *task)
 		return;
 	}
 
-	strncpy(comm, task->comm, TASK_COMM_LEN);
+	__get_task_comm(comm, TASK_COMM_LEN, task);
 }
 
 static void hist_elt_data_free(struct hist_elt_data *elt_data)
-- 
2.43.5