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=-0.3 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 E0BBEC433E0 for ; Sun, 17 May 2020 20:48:31 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9991720758 for ; Sun, 17 May 2020 20:48:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LJQu5C9+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9991720758 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies-bounces@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.93) (envelope-from ) id 1jaQCR-0001TP-Pq; Sun, 17 May 2020 16:47:55 -0400 Received: from mail-oi1-x244.google.com ([2607:f8b0:4864:20::244]) by shelob.surriel.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1jaQCP-0001TI-G9 for kernelnewbies@kernelnewbies.org; Sun, 17 May 2020 16:47:53 -0400 Received: by mail-oi1-x244.google.com with SMTP id o7so7354226oif.2 for ; Sun, 17 May 2020 13:47:52 -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; bh=aOGW5X0TGnwvfdKrZMYAVQyL8pOL2pG3Yh6nQN7pc+k=; b=LJQu5C9+BvFHQQ5nC51OFsHjqNeamH4oP3ywmBTTvspp8YNzR+qxuFO376WYn5hDg/ Q15X4+hHrcdVeLSIN1izTyXWrlua5s1tY87NTS+1G0THJc2krCFs5IRnoKyAAZESninv 4+Y//hPl8/FNRDSGa4VRiUEu+yokLxksiC2N4cXDb93kBD0ECkGRmrKLfrfe9JelwyQE 2OtIk4Eurk75RnnhyijTNr8veIFjB8ApCR5og16NtuZqI65BnHdXmtQHTZX+572cMEe7 BUL5vB36laCsy/blvdz9qmIRhIopkbD8Lk2HMoz5cani+SuME8drs+9sUGsPUCM/f4PE UHzg== 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=aOGW5X0TGnwvfdKrZMYAVQyL8pOL2pG3Yh6nQN7pc+k=; b=ar6RCB9ZtfdoQEWwhcY6ID85mHwQ/6qPTngmt/XRsZc46pr8GC9AH+9Ft3jGKxBx5l h5k9tYgbuUoa7ZyYhE0RAoJD41X+Z1qgmLRasg8kFtRa5u163Auu+5kkuezm6YyH6juH kB4uanT0iS+mIoXbT/1BPS8mQ2Kv5LpOAzKqj2cZGB5eFjYAhzUT2J+IK4WDLU4X8uUu TLbvq9C9hT8fiYIVfGvzV16m7vXrvbpYixBlIom71+SKWD/emrY9LUi3sve9FptxIhEb 4Qb+g5k1/bOWMRn/2+6qKO/bju4papFoabSYBvMO6+sp4V4tXv6N109SoK77xZIvcn4k wkcw== X-Gm-Message-State: AOAM5309bUer67fFd0gdLsOu6k26kkJmlmIMwhLjVtRSPeKtUxHOPzTP fk9o5skjYamSqovjNvip2a2OFmwZF3e+ggjxoNU= X-Google-Smtp-Source: ABdhPJx9X7595DuhkP5qNYkqWJnw/kAliBoUDVWpj+5aW/c3otJ6HH3qda5gpv8JPsLo1WgncR8cI644/2Dp5g4s6dw= X-Received: by 2002:aca:e1d6:: with SMTP id y205mr164891oig.142.1589748410745; Sun, 17 May 2020 13:46:50 -0700 (PDT) MIME-Version: 1.0 References: <374485.1589637193@turing-police> In-Reply-To: From: Cong Wang Date: Sun, 17 May 2020 13:46:39 -0700 Message-ID: Subject: Re: general protection fault vs Oops To: Subhashini Rao Beerisetty Cc: Randy Dunlap , =?UTF-8?Q?Valdis_Kl=C4=93tnieks?= , LKML , kernelnewbies X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kernelnewbies-bounces@kernelnewbies.org On Sat, May 16, 2020 at 9:16 AM Subhashini Rao Beerisetty wrote: > Yes, those are out-of-tree modules. Basically, my question is, in > general what is the difference between 'general protection fault' and > 'Oops' failure in kernel mode. For your case, they are likely just different consequences of a same memory error. Let's assume it is a use-after-free, the behavior is UAF is undefined: If that memory freed by kernel is also unmapped from kernel address space, you would get a page fault when using it afterward, that is an Oops. Or if that memory freed by kernel gets reallocated and remapped as read-only, you would get a general protection error when you writing to it afterward. _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies