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 X-Spam-Level: X-Spam-Status: No, score=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CAA2C4320A for ; Wed, 25 Aug 2021 22:02:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0E7B960EE0 for ; Wed, 25 Aug 2021 22:02:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231920AbhHYWCz (ORCPT ); Wed, 25 Aug 2021 18:02:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229890AbhHYWCy (ORCPT ); Wed, 25 Aug 2021 18:02:54 -0400 Received: from mail-lf1-x12f.google.com (mail-lf1-x12f.google.com [IPv6:2a00:1450:4864:20::12f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 52D17C0613C1 for ; Wed, 25 Aug 2021 15:02:08 -0700 (PDT) Received: by mail-lf1-x12f.google.com with SMTP id z2so2074957lft.1 for ; Wed, 25 Aug 2021 15:02:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Ap07zgvRCzHUWZsKzTqV0nv5eVeNrhiykOkW+2Q+N8I=; b=V0RfDdAyEknz5KXI21deyJWGKBtldhdU7eYU32v3+FYtF8NzVK6ypPcrEQF8iGVh9+ R31/nL49iM2YuRMj6y07FYcnclwCqu87K4SCTWIdrCiyF816igVvCdfHYrfhyJ+UMKZJ YrIH5Sd3c7JRcix5m4U4SC4LSMyIbi24SUN22kt6fPeCw9xxYZe1jh0C2Aqi/HH0Tq5l K+1tLSG8Uzo4O2xuhUFeKcfFkgWa8dmjcF24ogJxzOUGVIddLld72otsgtWnMrEgJajR KrTIFh/vHsTkdSwzHCZwABYf8Li+J/BY75/krxwgZCKkUKe9uSRWfpqG3hKooSdUFzhU WbaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Ap07zgvRCzHUWZsKzTqV0nv5eVeNrhiykOkW+2Q+N8I=; b=hmNewilRUFOE/mOCIaAtXn1u8Q3Ei+5Q21bAuivr23IjUivNFWZ/Fj4vp3qYrRWARh 75YpaVw6+3Aq6y6lf/Apn2/kzKtWnZkBfnHdJ9q0V0TFRU6MVsykR+xAbJiMWJd50Aa6 tpko6Q+rDQsF5l4QkNnpARsd7m5vWMr2r36CcBUqNlSgDkDlGc3stiRnO2coZ1ODUabG wQwG06/qVjWbWJXT0HiFXO707+gEaGsBOQ+vEuQ/uY9s4lKG8Yfb4Y1McJSurEOQ3mXa 4gUB00xULlCG5LQIcESCo6awzBWlePeQvzEscMOKe6Fer8IrY5n0STTD3EgrcnzT9Wm6 BZsg== X-Gm-Message-State: AOAM533r+ytFi8S6dUV3czZYPwcUVJkUYPdMb2Sp3VRR4vMKfMggqFh7 WzoXcFp4qO97pTCIT0oz/sxW/ba6xHZ0MJ99A9ZqSQ== X-Google-Smtp-Source: ABdhPJww2+7yBE9cppy9XJx9RGtuG2b3Nw6jhEEVvCLdZyZzODN88Y5xBICzIm0DAaG/K8nuxqq2bli3ZyrX9IeaqDE= X-Received: by 2002:a19:f017:: with SMTP id p23mr190205lfc.547.1629928926500; Wed, 25 Aug 2021 15:02:06 -0700 (PDT) MIME-Version: 1.0 References: <20210822075122.864511-1-keescook@chromium.org> <20210822075122.864511-19-keescook@chromium.org> In-Reply-To: <20210822075122.864511-19-keescook@chromium.org> From: Nick Desaulniers Date: Wed, 25 Aug 2021 15:01:54 -0700 Message-ID: Subject: Re: [PATCH for-next 18/25] fortify: Prepare to improve strnlen() and strlen() warnings To: Kees Cook Cc: linux-kernel@vger.kernel.org, Francis Laniel , Rasmus Villemoes , Daniel Micay , Bart Van Assche , David Gow , linux-mm@kvack.org, clang-built-linux@googlegroups.com, linux-hardening@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org On Sun, Aug 22, 2021 at 12:57 AM Kees Cook wrote: > > In order to have strlen() use fortified strnlen() internally, swap their > positions in the source. Doing this as part of later changes makes > review difficult, so reoroder it here; no code changes. > > Cc: Francis Laniel > Signed-off-by: Kees Cook Reviewed-by: Nick Desaulniers > --- > include/linux/fortify-string.h | 22 +++++++++++----------- > 1 file changed, 11 insertions(+), 11 deletions(-) > > diff --git a/include/linux/fortify-string.h b/include/linux/fortify-string.h > index 68bc5978d916..a3cb1d9aacce 100644 > --- a/include/linux/fortify-string.h > +++ b/include/linux/fortify-string.h > @@ -56,6 +56,17 @@ __FORTIFY_INLINE char *strcat(char *p, const char *q) > return p; > } > > +extern __kernel_size_t __real_strnlen(const char *, __kernel_size_t) __RENAME(strnlen); > +__FORTIFY_INLINE __kernel_size_t strnlen(const char *p, __kernel_size_t maxlen) > +{ > + size_t p_size = __builtin_object_size(p, 1); > + __kernel_size_t ret = __real_strnlen(p, maxlen < p_size ? maxlen : p_size); > + > + if (p_size <= ret && maxlen != ret) > + fortify_panic(__func__); > + return ret; > +} > + > __FORTIFY_INLINE __kernel_size_t strlen(const char *p) > { > __kernel_size_t ret; > @@ -71,17 +82,6 @@ __FORTIFY_INLINE __kernel_size_t strlen(const char *p) > return ret; > } > > -extern __kernel_size_t __real_strnlen(const char *, __kernel_size_t) __RENAME(strnlen); > -__FORTIFY_INLINE __kernel_size_t strnlen(const char *p, __kernel_size_t maxlen) > -{ > - size_t p_size = __builtin_object_size(p, 1); > - __kernel_size_t ret = __real_strnlen(p, maxlen < p_size ? maxlen : p_size); > - > - if (p_size <= ret && maxlen != ret) > - fortify_panic(__func__); > - return ret; > -} > - > /* defined after fortified strlen to reuse it */ > extern size_t __real_strlcpy(char *, const char *, size_t) __RENAME(strlcpy); > __FORTIFY_INLINE size_t strlcpy(char *p, const char *q, size_t size) > -- > 2.30.2 > > -- > You received this message because you are subscribed to the Google Groups "Clang Built Linux" group. > To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/20210822075122.864511-19-keescook%40chromium.org. -- Thanks, ~Nick Desaulniers