From patchwork Wed Oct 9 13:21:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13828432 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C7C111946AA; Wed, 9 Oct 2024 13:21:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728480074; cv=none; b=pK9aeOkpYqoUcBWcFHysyUNyzWrl5RWwV5TgE4nFZoFAhDJTO8W8lmks0fIwTLOPO6wGo2MlGgel1Ua1Qizr36zRXK2mvbAIVh9GwBfIVGEZpC+QFcKzsT3+/VUI4fYFLENEX3HQwsfGM/b6ZgY6uNV70l0IlJGdX0vaFdo6ARk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728480074; c=relaxed/simple; bh=tNZGbEZF4Exmspvj9tewG9lbswuRNTWCnITw4IhQQkA=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=ItUmYfsNTpDmdFiG/5JZAbkCZwHbFHLMXbE7L9mRO2qAOQFHXyUxP1IMsqoeRzWrZP4idKN9XfPx6lCBbeJ47rvAO/tfrO7iA6nYR2LyqwtSjI4UgNS/r6wDQHk1zTu4iYp3AWES8IUpZxfR+ux/oUS0MaxTHD96nLFL0cD59dE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7841AC4CED1; Wed, 9 Oct 2024 13:21:14 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98) (envelope-from ) id 1syWcx-0000000176L-41mA; Wed, 09 Oct 2024 09:21:19 -0400 Message-ID: <20241009132119.818724987@goodmis.org> User-Agent: quilt/0.68 Date: Wed, 09 Oct 2024 09:21:06 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , linux-hardening@vger.kernel.org, Kees Cook , Justin Stitt Subject: [for-next][PATCH 2/6] tracing/branch-profiler: Replace deprecated strncpy with strscpy References: <20241009132104.470687911@goodmis.org> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Justin Stitt strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. Both of these fields want to be NUL-terminated as per their use in printk: F_printk("%u:%s:%s (%u)%s", __entry->line, __entry->func, __entry->file, __entry->correct, __entry->constant ? " CONSTANT" : "") Use strscpy() as it NUL-terminates the destination buffer, so it doesn't have to be done manually. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@vger.kernel.org Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Kees Cook Link: https://lore.kernel.org/20240826-strncpy-kernel-trace-trace_branch-c-v1-1-b2c14f2e9e84@google.com Signed-off-by: Justin Stitt Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_branch.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index e47fdb4c92fb..aa63548873c3 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -74,10 +74,8 @@ probe_likely_condition(struct ftrace_likely_data *f, int val, int expect) p--; p++; - strncpy(entry->func, f->data.func, TRACE_FUNC_SIZE); - strncpy(entry->file, p, TRACE_FILE_SIZE); - entry->func[TRACE_FUNC_SIZE] = 0; - entry->file[TRACE_FILE_SIZE] = 0; + strscpy(entry->func, f->data.func); + strscpy(entry->file, p); entry->constant = f->constant; entry->line = f->data.line; entry->correct = val == expect;