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[23.128.96.18]) by mx.google.com with ESMTP id lw2si2701344ejb.328.2020.04.22.00.23.54; Wed, 22 Apr 2020 00:24:17 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=Gpj2Gyc8; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726415AbgDVHWy (ORCPT + 99 others); Wed, 22 Apr 2020 03:22:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35756 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725786AbgDVHWx (ORCPT ); Wed, 22 Apr 2020 03:22:53 -0400 Received: from mail-ed1-x543.google.com (mail-ed1-x543.google.com [IPv6:2a00:1450:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 724A3C03C1A6; Wed, 22 Apr 2020 00:22:53 -0700 (PDT) Received: by mail-ed1-x543.google.com with SMTP id r16so752614edw.5; Wed, 22 Apr 2020 00:22:53 -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=uG6Og2QY3Jrt6pTu1AnmMqNruS91FdRXUooE0XdBD+8=; b=Gpj2Gyc8l3uOMNmeMD9MdFBn6dKr8nXeTcwutYx8Lg0zJSPXXDAlQE7RI3lcNmNwfy mVgYkC3JV0D67+7dirmdeUFZAismXWLuYMX/Qy4mxdaPDvhzdtF2kP3LHs5fRE4LwRZj o66vVRkHQJFTwQ/adikAVhOxj1HvtXb9fNVGR58sK46Cztvmtd+GwcaWzcnnx518Wqrl oonmE0VTv8Hh0LSW01IATsV7PPePqp3tuxaFkzH2WP2MOMVBaDzLZblL8lmgfJOfflIp CWZNqBk4Dal8iV6YCDVxVJcAaw3GReHPLDWEOHvqU1bJVlAbUXHXsNhqRIRaLWu9CTo9 fYrw== 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=uG6Og2QY3Jrt6pTu1AnmMqNruS91FdRXUooE0XdBD+8=; b=VKpjofRJKBrKnptdHbd+RFC6rH4JnsMtWE01qmc1p/D7Z8YEzoFBEJcj82EQmNeaGf q46Cm1yn0VtjidSssMD/VjaidsJb3Qnd7Rk6OpoAvFXVKg23JiHgvFWMia9XNBvBO6ri SUFAy2hNsALetf8USXkh71ad1Z09oXK5DF6XjbdJP0ufILqsLpv/Fqzi1ZkcU4+V7gQs Z1i+Y8W+ul8VQmI7L5XK/EqAiM1CPHIbEpjBjqZ0bX7LYYzBOsMlUcpjyGjMuXN4Z9Fs u3oURGBWoT4f/1r8S/BmlA0PrUzsqH3b9KDFlDmkoMs97iKfkOpwF3cIi5Y9F8yT8M+R qZ5w== X-Gm-Message-State: AGi0PuYBBL1XGhQpMFNXLlIzmS7RL+OilrPt8nhU9/Xk5LWOamDJmF9Q 32aJrFLjQyHLu2dPYECpM3dGcWyc/EmLWF9Gv3E= X-Received: by 2002:aa7:da8b:: with SMTP id q11mr22791260eds.359.1587540172116; Wed, 22 Apr 2020 00:22:52 -0700 (PDT) MIME-Version: 1.0 References: <20200421171552.28393-1-luke.r.nels@gmail.com> <6f1130b3-eaea-cc5e-716f-5d6be77101b9@zytor.com> <05CE7897-C58E-40C0-8E08-C8E948B70286@zytor.com> In-Reply-To: <05CE7897-C58E-40C0-8E08-C8E948B70286@zytor.com> From: Xi Wang Date: Wed, 22 Apr 2020 00:22:16 -0700 Message-ID: Subject: Re: [PATCH bpf 1/2] bpf, x32: Fix invalid instruction in BPF_LDX zero-extension To: hpa@zytor.com Cc: Luke Nelson , bpf@vger.kernel.org, Luke Nelson , Wang YanQing , "David S. Miller" , Alexey Kuznetsov , Hideaki YOSHIFUJI , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , Andrii Nakryiko , John Fastabend , KP Singh , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 22, 2020 at 12:13 AM wrote: > C7 C0 0 is *not* an invalid instruction, although it is incomplete. It is a different, but arguably even more serious, problem. Yep, it would "eat" three bytes coming after that. :)