diff mbox series

[v3,09/11] tracing: Replace strncpy() with __get_task_comm()

Message ID 20240621022959.9124-10-laoar.shao@gmail.com (mailing list archive)
State Handled Elsewhere
Headers show
Series Improve the copy of task comm | expand

Commit Message

Yafang Shao June 21, 2024, 2:29 a.m. UTC
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@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---
 kernel/trace/trace.c             | 2 +-
 kernel/trace/trace_events_hist.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

Comments

Masami Hiramatsu (Google) June 21, 2024, 4:37 a.m. UTC | #1
On Fri, 21 Jun 2024 10:29:57 +0800
Yafang Shao <laoar.shao@gmail.com> wrote:

> 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.

Good catch! Looks good to me.

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thank you,

> 
> Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> Cc: Mathieu Desnoyers <mathieu.desnoyers@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)
> -- 
> 2.39.1
>
diff mbox series

Patch

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)