[v5,7/9] tracing: Replace strncpy() with __get_task_comm()

Message ID	20240804075619.20804-8-laoar.shao@gmail.com (mailing list archive)
State	New
Headers	show Return-Path: <owner-linux-mm@kvack.org> From: Yafang Shao <laoar.shao@gmail.com> To: akpm@linux-foundation.org Cc: torvalds@linux-foundation.org, ebiederm@xmission.com, alexei.starovoitov@gmail.com, rostedt@goodmis.org, catalin.marinas@arm.com, penguin-kernel@i-love.sakura.ne.jp, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, audit@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org, dri-devel@lists.freedesktop.org, Yafang Shao <laoar.shao@gmail.com>, Masami Hiramatsu <mhiramat@kernel.org>, Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Subject: [PATCH v5 7/9] tracing: Replace strncpy() with __get_task_comm() Date: Sun, 4 Aug 2024 15:56:17 +0800 Message-Id: <20240804075619.20804-8-laoar.shao@gmail.com> In-Reply-To: <20240804075619.20804-1-laoar.shao@gmail.com> References: <20240804075619.20804-1-laoar.shao@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org Precedence: bulk
Series	Improve the copy of task comm \| expand [v5,0/9] Improve the copy of task comm [v5,1/9] fs/exec: Drop task_lock() inside __get_task_comm() [v5,2/9] auditsc: Replace memcpy() with __get_task_comm() [v5,3/9] security: Replace memcpy() with __get_task_comm() [v5,4/9] bpftool: Ensure task comm is always NUL-terminated [v5,5/9] mm/util: Fix possible race condition in kstrdup() [v5,6/9] mm/util: Deduplicate code in {kstrdup,kstrndup,kmemdup_nul} [v5,7/9] tracing: Replace strncpy() with __get_task_comm() [v5,8/9] net: Replace strcpy() with __get_task_comm() [v5,9/9] drm: Replace strcpy() with __get_task_comm()

Message ID

20240804075619.20804-8-laoar.shao@gmail.com (mailing list archive)

State

New

Headers

From: Yafang Shao <laoar.shao@gmail.com>
To: akpm@linux-foundation.org
Cc: torvalds@linux-foundation.org,
	ebiederm@xmission.com,
	alexei.starovoitov@gmail.com,
	rostedt@goodmis.org,
	catalin.marinas@arm.com,
	penguin-kernel@i-love.sakura.ne.jp,
	linux-mm@kvack.org,
	linux-fsdevel@vger.kernel.org,
	linux-trace-kernel@vger.kernel.org,
	audit@vger.kernel.org,
	linux-security-module@vger.kernel.org,
	selinux@vger.kernel.org,
	bpf@vger.kernel.org,
	netdev@vger.kernel.org,
	dri-devel@lists.freedesktop.org,
	Yafang Shao <laoar.shao@gmail.com>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: [PATCH v5 7/9] tracing: Replace strncpy() with __get_task_comm()
Date: Sun,  4 Aug 2024 15:56:17 +0800
Message-Id: <20240804075619.20804-8-laoar.shao@gmail.com>
In-Reply-To: <20240804075619.20804-1-laoar.shao@gmail.com>
References: <20240804075619.20804-1-laoar.shao@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: owner-linux-mm@kvack.org
Precedence: bulk

Series

Improve the copy of task comm | expand

Commit Message

Yafang Shao Aug. 4, 2024, 7:56 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>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.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 10cd38bce2f1..985d2bf2bbc5 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)

[v5,7/9] tracing: Replace strncpy() with __get_task_comm()

Commit Message

Patch