From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 764E9EB64DA for ; Wed, 5 Jul 2023 14:28:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230268AbjGEO2l (ORCPT ); Wed, 5 Jul 2023 10:28:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42544 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229645AbjGEO2k (ORCPT ); Wed, 5 Jul 2023 10:28:40 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79F80CF; Wed, 5 Jul 2023 07:28:39 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id EF4F86159F; Wed, 5 Jul 2023 14:28:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A5545C433C8; Wed, 5 Jul 2023 14:28:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1688567318; bh=TFMultyCiWda4KqG2aspwa/c8KG/qnRXC4jDSPWHiV0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=sqnYitwY9oor9zy9dQd4mn6pgHajKayzFd8zuSMZxLafAukkvKo5NwCiTT3xKDTbE fR3tN7mbvFf4TY3QMc98egFELwbAGD2XuE4QgNE/1/KPNtEEukVHJiI19V5SZCH/MD pIYJrBX6iX2vm3qBX7WUKDxuoNGOE4Rj18R+vOq3uNC4jVG7KvtRE8BgsoWDwFS7j9 Z6kQbceUYsq2q9zQYTg5KgmyFSt7PXBB7l8FbSNESlEpaUx33xEG0QmyQXw17nMdLy gPXtrJkkzYJ88u1S4r5cHft37ilKk2Kqahs4EFILIsI8NbBoAlgBe5ocPP8xdX2uPo fxhNFvViEUP5w== Date: Wed, 5 Jul 2023 23:28:34 +0900 From: Masami Hiramatsu (Google) To: Steven Rostedt Cc: LKML , Linux trace kernel , Masami Hiramatsu , Mark Rutland , Azeem Shaikh , Kees Cook Subject: Re: [PATCH] tracing/boot: Test strscpy() against less than zero for error Message-Id: <20230705232834.f71d8602c3c9d9c56abd0b15@kernel.org> In-Reply-To: <20230704100807.707d1605@rorschach.local.home> References: <20230704100807.707d1605@rorschach.local.home> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org On Tue, 4 Jul 2023 10:08:07 -0400 Steven Rostedt wrote: > From: "Steven Rostedt (Google)" > > Instead of checking for -E2BIG, it is better to just check for less than > zero of strscpy() for error. Testing for -E2BIG is not very robust, and > the calling code does not really care about the error code, just that > there was an error. > > One of the updates to convert strlcpy() to strscpy() had a v2 version > that changed the test from testing against -E2BIG to less than zero, but I > took the v1 version that still tested for -E2BIG. Indeed. This looks good to me. Acked-by: Masami Hiramatsu (Google) Thank you, > > Link: https://lore.kernel.org/linux-trace-kernel/20230615180420.400769-1-azeemshaikh38@gmail.com/ > > Signed-off-by: Steven Rostedt (Google) > --- > kernel/trace/trace_boot.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c > index 5fe525f1b8cc..7ccc7a8e155b 100644 > --- a/kernel/trace/trace_boot.c > +++ b/kernel/trace/trace_boot.c > @@ -31,7 +31,7 @@ trace_boot_set_instance_options(struct trace_array *tr, struct xbc_node *node) > > /* Common ftrace options */ > xbc_node_for_each_array_value(node, "options", anode, p) { > - if (strscpy(buf, p, ARRAY_SIZE(buf)) == -E2BIG) { > + if (strscpy(buf, p, ARRAY_SIZE(buf)) < 0) { > pr_err("String is too long: %s\n", p); > continue; > } > @@ -87,7 +87,7 @@ trace_boot_enable_events(struct trace_array *tr, struct xbc_node *node) > const char *p; > > xbc_node_for_each_array_value(node, "events", anode, p) { > - if (strscpy(buf, p, ARRAY_SIZE(buf)) == -E2BIG) { > + if (strscpy(buf, p, ARRAY_SIZE(buf)) < 0) { > pr_err("String is too long: %s\n", p); > continue; > } > @@ -486,7 +486,7 @@ trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode, > > p = xbc_node_find_value(enode, "filter", NULL); > if (p && *p != '\0') { > - if (strscpy(buf, p, ARRAY_SIZE(buf)) == -E2BIG) > + if (strscpy(buf, p, ARRAY_SIZE(buf)) < 0) > pr_err("filter string is too long: %s\n", p); > else if (apply_event_filter(file, buf) < 0) > pr_err("Failed to apply filter: %s\n", buf); > @@ -494,7 +494,7 @@ trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode, > > if (IS_ENABLED(CONFIG_HIST_TRIGGERS)) { > xbc_node_for_each_array_value(enode, "actions", anode, p) { > - if (strscpy(buf, p, ARRAY_SIZE(buf)) == -E2BIG) > + if (strscpy(buf, p, ARRAY_SIZE(buf)) < 0) > pr_err("action string is too long: %s\n", p); > else if (trigger_process_regex(file, buf) < 0) > pr_err("Failed to apply an action: %s\n", p); > -- > 2.39.2 > -- Masami Hiramatsu (Google)