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 6126EC7EE22 for ; Wed, 17 May 2023 22:28:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229485AbjEQW2V (ORCPT ); Wed, 17 May 2023 18:28:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbjEQW2V (ORCPT ); Wed, 17 May 2023 18:28:21 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C8F959DE; Wed, 17 May 2023 15:28:20 -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 DDABE648F9; Wed, 17 May 2023 22:28:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7AF56C433EF; Wed, 17 May 2023 22:28:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684362499; bh=KFREZcjLEiG8NztAj50tdQP1RgWuzfuivuMpu6iL7lU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=MOMp5wi3hbzvqfoqvTmUUvhRxNtlfo0gRfrFFmV/bCdLQOO7cwZpflzzSzuuXqEB2 tYeAsfOOqSmRLo+su9SOHiMUxFaavhgpYZsMR0Zkva2gldyrF2Z2j7vpYw/ivMFcAa l/1oFEpvLe3O30sVjNvzRi64h4PZBwcxtV0la0JFSyk92grL4l8x4TZWKkyMEPfVI2 w5AW9BgnguEIhVKbWrw2Qn2j++ySHAyBfTNUsI/SY6IF0lrKrPYqECvbTFMVYBMp4h KGIB3tLsKC7cDlqnKP4bIqFM8r1Rz5LNQB7IlenQFlBUny35vQAHkOYuKcFDi88Jpe KChVFVrEgK0cA== Date: Thu, 18 May 2023 07:28:15 +0900 From: Masami Hiramatsu (Google) To: Azeem Shaikh Cc: Steven Rostedt , linux-hardening@vger.kernel.org, Mark Rutland , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH] ftrace: Replace all non-returning strlcpy with strscpy Message-Id: <20230518072815.53fd9f67a3423d85f133d98b@kernel.org> In-Reply-To: <20230517145323.1522010-1-azeemshaikh38@gmail.com> References: <20230517145323.1522010-1-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-trace-kernel@vger.kernel.org On Wed, 17 May 2023 14:53:23 +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 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) Thanks! > --- > kernel/trace/ftrace.c | 18 +++++++++--------- > 1 file changed, 9 insertions(+), 9 deletions(-) > > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c > index 764668467155..6a77edb51f18 100644 > --- a/kernel/trace/ftrace.c > +++ b/kernel/trace/ftrace.c > @@ -5743,7 +5743,7 @@ bool ftrace_filter_param __initdata; > static int __init set_ftrace_notrace(char *str) > { > ftrace_filter_param = true; > - strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); > + strscpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); > return 1; > } > __setup("ftrace_notrace=", set_ftrace_notrace); > @@ -5751,7 +5751,7 @@ __setup("ftrace_notrace=", set_ftrace_notrace); > static int __init set_ftrace_filter(char *str) > { > ftrace_filter_param = true; > - strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); > + strscpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); > return 1; > } > __setup("ftrace_filter=", set_ftrace_filter); > @@ -5763,14 +5763,14 @@ static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); > > static int __init set_graph_function(char *str) > { > - strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); > + strscpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); > return 1; > } > __setup("ftrace_graph_filter=", set_graph_function); > > static int __init set_graph_notrace_function(char *str) > { > - strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); > + strscpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); > return 1; > } > __setup("ftrace_graph_notrace=", set_graph_notrace_function); > @@ -6569,8 +6569,8 @@ static int ftrace_get_trampoline_kallsym(unsigned int symnum, > continue; > *value = op->trampoline; > *type = 't'; > - strlcpy(name, FTRACE_TRAMPOLINE_SYM, KSYM_NAME_LEN); > - strlcpy(module_name, FTRACE_TRAMPOLINE_MOD, MODULE_NAME_LEN); > + strscpy(name, FTRACE_TRAMPOLINE_SYM, KSYM_NAME_LEN); > + strscpy(module_name, FTRACE_TRAMPOLINE_MOD, MODULE_NAME_LEN); > *exported = 0; > return 0; > } > @@ -6933,7 +6933,7 @@ ftrace_func_address_lookup(struct ftrace_mod_map *mod_map, > if (off) > *off = addr - found_func->ip; > if (sym) > - strlcpy(sym, found_func->name, KSYM_NAME_LEN); > + strscpy(sym, found_func->name, KSYM_NAME_LEN); > > return found_func->name; > } > @@ -6987,8 +6987,8 @@ int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value, > > *value = mod_func->ip; > *type = 'T'; > - strlcpy(name, mod_func->name, KSYM_NAME_LEN); > - strlcpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); > + strscpy(name, mod_func->name, KSYM_NAME_LEN); > + strscpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); > *exported = 1; > preempt_enable(); > return 0; > -- Masami Hiramatsu (Google)