From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [91.216.245.30]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D653E2BE7CD; Sun, 12 Apr 2026 17:17:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.216.245.30 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776014246; cv=none; b=GgBb4RvgMN708aXM/3j/FjrFzLLj+0AdGryE0FYHGK/3xtVLlrf7J0D/c5SXXmCIvscs0r5/pf9xrPO+n8fylcihNwCFq/u4WOK5muW8Tv5jRox6W7DRtE+KJpcwKhM2XmjS/jVgsCdA76P/7Or+zgLiHw3FBimGyG/DZBXS6HI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776014246; c=relaxed/simple; bh=CzfTOj4mUNn2bmRFGl/gGFgp2GcpRDFPE4OAXwXXrJs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=n0MDq3BKJWN+9nC0uJX5NwEmCKb5BaKnV72AKfKs6H9KnWZuTr026crufOg+6C6KyUgQA7CINbf2hk3X8It6GKTMVkbYLlBSd3RvTdeZxW6MCNfJf76G7vfokPoPkm9aAzIeHh0D9l95Q45qUG3pzDPKki4lTv2evmLnrKIgTG0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=strlen.de; spf=pass smtp.mailfrom=strlen.de; arc=none smtp.client-ip=91.216.245.30 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=strlen.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=strlen.de Received: by Chamillionaire.breakpoint.cc (Postfix, from userid 1003) id C6D26602AB; Sun, 12 Apr 2026 19:17:22 +0200 (CEST) Date: Sun, 12 Apr 2026 19:17:22 +0200 From: Florian Westphal To: Jakub Kicinski Cc: netdev@vger.kernel.org, Paolo Abeni , "David S. Miller" , Eric Dumazet , netfilter-devel@vger.kernel.org, pablo@netfilter.org Subject: Re: [PATCH net-next 00/11] netfilter: updates for net-next Message-ID: References: <20260410112352.23599-1-fw@strlen.de> <20260412094049.7b01dd7b@kernel.org> Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Florian Westphal wrote: > Jakub Kicinski wrote: > https://sashiko.dev/#/patchset/20260410112352.23599-1-fw%40strlen.de Forgot to mention this: --------------- AF_PACKET raw sockets or tun devices, the network_header might be uninitialized (~0U). In this state, skb_mac_header_len() will evaluate to a very large number, bypassing the ETH_HLEN check completely. --------------- Really? TIL. --------------------- Furthermore, skb_mac_header_len() only verifies the logical distance between header offsets, rather than ensuring the bytes are actually present in the physical linear buffer. --------------- Really? Total news to me :-(