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=-6.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 25DEDC4727C for ; Tue, 22 Sep 2020 03:57:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD70D23A32 for ; Tue, 22 Sep 2020 03:57:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="dPC6uIvp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728922AbgIVD5v (ORCPT ); Mon, 21 Sep 2020 23:57:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728897AbgIVD5u (ORCPT ); Mon, 21 Sep 2020 23:57:50 -0400 Received: from mail-vs1-xe43.google.com (mail-vs1-xe43.google.com [IPv6:2607:f8b0:4864:20::e43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 19438C061755 for ; Mon, 21 Sep 2020 20:57:50 -0700 (PDT) Received: by mail-vs1-xe43.google.com with SMTP id p24so4516246vsf.8 for ; Mon, 21 Sep 2020 20:57:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=EkUjUieCb6XRK6uMlDV2dbwExrL7ULDE403JBTQMbwM=; b=dPC6uIvpOEmGqHW4WivurYxYCFSJHZfgFJDFtzIWLMhx4cIEIxkN/KxiBhD5WJaVz2 aifgipxlkEm0y9WvPjFzVOZIfyBxc5IyvAKjZt/3hAYP5Lk4E4O8uOgNLin3Htyr+np8 sjtOgr918HNnA067xHasLX5RdXcQSi7kyAQw9wkrtx1bVAfAPEeFb3+mLXHgeLE+K3kg RBSUvRiojkRrFyfZV0/TeqgoH4JRDbg4mQBUEplTB/iTdeDnQQBLx8V8Sdsq6ttEvOsp Z0ze6VZks1W+IFccjmfAk2nEw+Fpfk/yeeqhhBAIBuRUDW6akbnLG8wwYlshF0Tx/SEe I8TQ== 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:content-transfer-encoding; bh=EkUjUieCb6XRK6uMlDV2dbwExrL7ULDE403JBTQMbwM=; b=jBlPsJl4tWAI6t9rfvD7joO4gHGk19NxuFqV6OpzPHlIIlaVP1jtfel7+SJpsa7tXc 75WPkiQoIQR9RsbmgrFCB/dhGaofCz8lGIApNNGLpdVcgsnB+2Jn5kMrkbUMdl5xVO6L FNc/H+iPmaWE42NpAKE0V77Ub9jWEuan59WWuwiwO3vwbLsqng5VlZQpbbtMerwiBWjA HFT1kdbD9tN0ndYeKL8haJ2wgxpxZdbVG/cH3tkPi/Ik6mViqRHzdcu4LZRHeSuW0pKd PGLwj4UNjbpea7n/w4rTOtbYmoR16fVAjfUdhVHXfkzFAR5UTyOv2o01hiKEsVJH6+Sw JxYw== X-Gm-Message-State: AOAM530+Lx9UrrGExU2Oo/oy8vcW9B07cirov0hAhaNAvyl3kIKNoM6U w/hyycfpGD+zJwsGI8MVNSYuubFJuQcnYMA/+SNAGQ5STRaaoA== X-Google-Smtp-Source: ABdhPJyU2TYRB3f91Xk/UVfh76QqpMtsFxWcw8JGgLpVKKxUbUBGXpHljYCrgcFxuCyBxzOU5dPUe49CKZb7xGPo2Os= X-Received: by 2002:a67:f90d:: with SMTP id t13mr2207494vsq.60.1600747069091; Mon, 21 Sep 2020 20:57:49 -0700 (PDT) MIME-Version: 1.0 References: <20200921190433.1149521-1-jim.cromie@gmail.com> <20200921190433.1149521-2-jim.cromie@gmail.com> <88110ffe6b08a2b403f30f4ea7463d5dad50b80b.camel@perches.com> In-Reply-To: <88110ffe6b08a2b403f30f4ea7463d5dad50b80b.camel@perches.com> From: jim.cromie@gmail.com Date: Mon, 21 Sep 2020 21:57:22 -0600 Message-ID: Subject: Re: [PATCH 1/2] dyndbg: dont panic over bad input To: Joe Perches Cc: Jason Baron , Greg KH , LKML , Petr Mladek Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 21, 2020 at 1:29 PM Joe Perches wrote: > > On Mon, 2020-09-21 at 13:04 -0600, Jim Cromie wrote: > > This BUG_ON, from 2009, caught the impossible case of a word-char both > > starting and ending a string (loosely speaking). A bad (reverted) > > patch finally hit this case, but even "impossibly bad input" is no > > reason to panic the kernel. Instead pr_err and return -EINVAL. > [] > > diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c > [] > > @@ -259,7 +259,10 @@ static int ddebug_tokenize(char *buf, char *words[= ], int maxwords) > > } else { > > for (end =3D buf; *end && !isspace(*end); end++) > > ; > > - BUG_ON(end =3D=3D buf); > > + if (end =3D=3D buf) { > > + pr_err("expected non-empty bareword"); > > missing newline > > This message is also unintelligible. > What is a non-empty bareword? > > hmm, I borrowed the term from perl en.wiktionary.org =E2=80=BA wiki =E2=80=BA bareword (programming, chiefly Perl) A sequence of text characters in source code that do not form a keyword nor part of a quoted string, and may potentially be interpreted ... basically, a not-quoted word, a keyword or not-quoted-value Im open that there might be better terminology. have any suggestions ?