From nobody Tue Feb 10 22:15:46 2026 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 AAED4EB64DD for ; Wed, 5 Jul 2023 14:46:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232686AbjGEOqo (ORCPT ); Wed, 5 Jul 2023 10:46:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232244AbjGEOqg (ORCPT ); Wed, 5 Jul 2023 10:46:36 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6BEDF10D5 for ; Wed, 5 Jul 2023 07:46:34 -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 EB66F615C9 for ; Wed, 5 Jul 2023 14:46:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5D96BC433C8; Wed, 5 Jul 2023 14:46:33 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.96) (envelope-from ) id 1qH3m4-003PiJ-1Y; Wed, 05 Jul 2023 10:46:32 -0400 Message-ID: <20230705144632.294731621@goodmis.org> User-Agent: quilt/0.66 Date: Wed, 05 Jul 2023 10:40:34 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Andrew Morton , Azeem Shaikh , Kees Cook Subject: [for-linus][PATCH 3/3] tracing/boot: Test strscpy() against less than zero for error References: <20230705144031.702796304@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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. Link: https://lore.kernel.org/linux-trace-kernel/20230615180420.400769-1-az= eemshaikh38@gmail.com/ Link: https://lore.kernel.org/linux-trace-kernel/20230704100807.707d1605@ro= rschach.local.home Cc: Mark Rutland Cc: Azeem Shaikh Cc: Kees Cook Acked-by: Masami Hiramatsu (Google) 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, s= truct xbc_node *node) =20 /* Common ftrace options */ xbc_node_for_each_array_value(node, "options", anode, p) { - if (strscpy(buf, p, ARRAY_SIZE(buf)) =3D=3D -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 x= bc_node *node) const char *p; =20 xbc_node_for_each_array_value(node, "events", anode, p) { - if (strscpy(buf, p, ARRAY_SIZE(buf)) =3D=3D -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, struc= t xbc_node *gnode, =20 p =3D xbc_node_find_value(enode, "filter", NULL); if (p && *p !=3D '\0') { - if (strscpy(buf, p, ARRAY_SIZE(buf)) =3D=3D -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, struc= t xbc_node *gnode, =20 if (IS_ENABLED(CONFIG_HIST_TRIGGERS)) { xbc_node_for_each_array_value(enode, "actions", anode, p) { - if (strscpy(buf, p, ARRAY_SIZE(buf)) =3D=3D -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); --=20 2.39.2