From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-180.mta1.migadu.com (out-180.mta1.migadu.com [95.215.58.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6ED232E8882 for ; Mon, 11 Aug 2025 18:18:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754936333; cv=none; b=myArvbHPXzI8hU6qDOVZBIQqJEUGRPUTbqDjfEUN3gzwUxa+8JeA59dOe+kNQOZAlvZmG3XIsb3F5C7BjNtPLZMFIKMpWZAEdj9laFhg5GMrKdvWtBcFMPgAXVNd+lGS5OqE86kPCMxOsejz4KnufzT2JbyvsiZ33CwiHyuHk6E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754936333; c=relaxed/simple; bh=C+7n0IjmcMmLKd/Szc/G9DbwWG0qsCK8b/b02dPy2Zg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=RM5NhhIVDtKn9p2kCjLJ/D7Ai3KvMKozKaFe4P6rRE7DW3Te6C9tL2HFTlaTpGTm1UV0lhXasW+yKdP3m5ks1KxOiYlYo/Yj2mn3Rqic98XfKxKs6UFwvZBT0NmJFxeXI47CHWkF4mYR0ExwlncDPxDvLhB0KPXjhl+kxDgXZ9c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=bpU6Vyj1; arc=none smtp.client-ip=95.215.58.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="bpU6Vyj1" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1754936329; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=TkTc44JI4zDg+YVIapfB2t3E3nAxyECO9is12fjWfMY=; b=bpU6Vyj1lUEZL2TLJkB7oz99xDoPEWP7o/yDjigqMYhVN9w+PPqSZIO+xycwi5rKdJIqYu uIbj+q1tyOPxYpBwKf9fsSawvDVfDkL8xcgYzBoX5Dwa5b85olWzcLrZ36g9s3jYBXk8WK Vun6dojR38lC69mp8Ynqw64mvCgRVyU= From: Thorsten Blum To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , "Liang, Kan" Cc: Thorsten Blum , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] perf/core: Replace memset(0) + strscpy() with strscpy_pad() Date: Mon, 11 Aug 2025 20:18:03 +0200 Message-ID: <20250811181802.72970-2-thorsten.blum@linux.dev> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Replace memset(0) followed by strscpy() with strscpy_pad() to improve perf_event_comm_event(). This avoids zeroing the memory before copying the string and ensures the destination buffer is only written to once, simplifying the code and improving efficiency. Signed-off-by: Thorsten Blum --- Changes in v2: - Keep strlen() as we're not checking the return value of strscpy_pad() for string truncation - Link to v1: https://lore.kernel.org/lkml/20250811091637.4492-2-thorsten.blum@linux.dev/ --- kernel/events/core.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 8060c2857bb2..414212b02d54 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8981,8 +8981,7 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event) char comm[TASK_COMM_LEN]; unsigned int size; - memset(comm, 0, sizeof(comm)); - strscpy(comm, comm_event->task->comm); + strscpy_pad(comm, comm_event->task->comm); size = ALIGN(strlen(comm)+1, sizeof(u64)); comm_event->comm = comm; -- 2.50.1