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 05407C77B75 for ; Tue, 16 May 2023 16:06:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234355AbjEPQGw (ORCPT ); Tue, 16 May 2023 12:06:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233831AbjEPQGt (ORCPT ); Tue, 16 May 2023 12:06:49 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B958EE5; Tue, 16 May 2023 09:06:47 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4A1F363397; Tue, 16 May 2023 16:06:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D6FDC433EF; Tue, 16 May 2023 16:06:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684253206; bh=aaPDpdXKFo27zJIkXjU1Qd3DKHP9ARhLfJfUTFTOqEY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Hpsa/jnho95UGexCV+NHnarr1vdLu7qZwJi8Q4AfhGFLs13dqsonyvEBZTtxjtGuI 03vTNJE9ZKhojPETwPzRJzKKSdi7hvSJdKGrRiqtUa0c1UEWhmnKhJ3oAvKh3N2XQz yXuP69wWQOA0BaMpBesqJ+aT/lmpsPa6WLjWK3adoxk8QkTIz8hrSw9Q9mFoCXkEmE 4IaGl9ePacPmCvNrefM3XOyOqASZ850HoIwT59lIrzA7Ztn7zTv5dojI2iFM2LAaLn 75lHGyhmG3V/lZoolVpRc4dYao9yYjSz5VUyFTSaw3P8uMJXHfQy48Lq8bUAwBAgtp VLEEaQem7ItOQ== Date: Wed, 17 May 2023 01:06:43 +0900 From: Masami Hiramatsu (Google) To: Azeem Shaikh Cc: Steven Rostedt , linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH v2] tracing: Replace all non-returning strlcpy with strscpy Message-Id: <20230517010643.aa4c5dc5e7e6787d72aa9012@kernel.org> In-Reply-To: <20230516143956.1367827-1-azeemshaikh38@gmail.com> References: <20230516143956.1367827-1-azeemshaikh38@gmail.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; 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-kernel@vger.kernel.org On Tue, 16 May 2023 14:39:56 +0000 Azeem Shaikh wrote: > strlcpy() reads the entire source buffer first. > This read may exceed the destination size limit. > This is both inefficient and can lead to linear read > overflows if a source string is not NUL-terminated [1]. > In an effort to remove strlcpy() completely [2], replace > strlcpy() here with strscpy(). > > No return values were used, so direct replacement with strlcpy is safe. > > [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy > [2] https://github.com/KSPP/linux/issues/89 > > Signed-off-by: Azeem Shaikh Looks good to me. Acked-by: Masami Hiramatsu (Google) Thank you, > --- > v1: https://lore.kernel.org/all/20230516043943.5234-1-azeemshaikh38@gmail.com/ > Changes from v1: > - Removed subsystem specific files. > - Minor update to commit log. > > kernel/trace/trace.c | 8 ++++---- > kernel/trace/trace_events.c | 4 ++-- > kernel/trace/trace_events_inject.c | 4 ++-- > kernel/trace/trace_kprobe.c | 2 +- > kernel/trace/trace_probe.c | 2 +- > 5 files changed, 10 insertions(+), 10 deletions(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index ebc59781456a..28ccd0c9bdf0 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -196,7 +196,7 @@ static int boot_snapshot_index; > > static int __init set_cmdline_ftrace(char *str) > { > - strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); > + strscpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); > default_bootup_tracer = bootup_tracer_buf; > /* We are using ftrace early, expand it */ > ring_buffer_expanded = true; > @@ -281,7 +281,7 @@ static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; > > static int __init set_trace_boot_options(char *str) > { > - strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); > + strscpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); > return 1; > } > __setup("trace_options=", set_trace_boot_options); > @@ -291,7 +291,7 @@ static char *trace_boot_clock __initdata; > > static int __init set_trace_boot_clock(char *str) > { > - strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); > + strscpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); > trace_boot_clock = trace_boot_clock_buf; > return 1; > } > @@ -2521,7 +2521,7 @@ static void __trace_find_cmdline(int pid, char comm[]) > if (map != NO_CMDLINE_MAP) { > tpid = savedcmd->map_cmdline_to_pid[map]; > if (tpid == pid) { > - strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN); > + strscpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN); > return; > } > } > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c > index 654ffa40457a..dc83a259915b 100644 > --- a/kernel/trace/trace_events.c > +++ b/kernel/trace/trace_events.c > @@ -2831,7 +2831,7 @@ static __init int setup_trace_triggers(char *str) > char *buf; > int i; > > - strlcpy(bootup_trigger_buf, str, COMMAND_LINE_SIZE); > + strscpy(bootup_trigger_buf, str, COMMAND_LINE_SIZE); > ring_buffer_expanded = true; > disable_tracing_selftest("running event triggers"); > > @@ -3621,7 +3621,7 @@ static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata; > > static __init int setup_trace_event(char *str) > { > - strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE); > + strscpy(bootup_event_buf, str, COMMAND_LINE_SIZE); > ring_buffer_expanded = true; > disable_tracing_selftest("running event tracing"); > > diff --git a/kernel/trace/trace_events_inject.c b/kernel/trace/trace_events_inject.c > index d6b4935a78c0..abe805d471eb 100644 > --- a/kernel/trace/trace_events_inject.c > +++ b/kernel/trace/trace_events_inject.c > @@ -217,7 +217,7 @@ static int parse_entry(char *str, struct trace_event_call *call, void **pentry) > char *addr = (char *)(unsigned long) val; > > if (field->filter_type == FILTER_STATIC_STRING) { > - strlcpy(entry + field->offset, addr, field->size); > + strscpy(entry + field->offset, addr, field->size); > } else if (field->filter_type == FILTER_DYN_STRING || > field->filter_type == FILTER_RDYN_STRING) { > int str_len = strlen(addr) + 1; > @@ -232,7 +232,7 @@ static int parse_entry(char *str, struct trace_event_call *call, void **pentry) > } > entry = *pentry; > > - strlcpy(entry + (entry_size - str_len), addr, str_len); > + strscpy(entry + (entry_size - str_len), addr, str_len); > str_item = (u32 *)(entry + field->offset); > if (field->filter_type == FILTER_RDYN_STRING) > str_loc -= field->offset + field->size; > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index 59cda19a9033..1b3fa7b854aa 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -30,7 +30,7 @@ static char kprobe_boot_events_buf[COMMAND_LINE_SIZE] __initdata; > > static int __init set_kprobe_boot_events(char *str) > { > - strlcpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE); > + strscpy(kprobe_boot_events_buf, str, COMMAND_LINE_SIZE); > disable_tracing_selftest("running kprobe events"); > > return 1; > diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c > index 2d2616678295..73055ba8d8ef 100644 > --- a/kernel/trace/trace_probe.c > +++ b/kernel/trace/trace_probe.c > @@ -254,7 +254,7 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup, > trace_probe_log_err(offset, GROUP_TOO_LONG); > return -EINVAL; > } > - strlcpy(buf, event, slash - event + 1); > + strscpy(buf, event, slash - event + 1); > if (!is_good_system_name(buf)) { > trace_probe_log_err(offset, BAD_GROUP_NAME); > return -EINVAL; > -- > 2.40.1.606.ga4b1b128d6-goog > > -- Masami Hiramatsu (Google)