From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f52.google.com (mail-ed1-f52.google.com [209.85.208.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F28A4908C2 for ; Thu, 8 Oct 2026 13:03:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.52 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791464610; cv=none; b=V9Q2ORltA0Aq8O2gWAltraJ46Dun5fhVJ8pdfYj+1gMiOtzdFE5ojmFv1xg26uJ/Yi/UPCdi3/mFbr4xvyFchPUMrg5Keo1zthcYHRj10xT4e0AFieLldre1ciPH8zCy0U2i/qdgKiQX+YxFHHQMq0ZsYCCWxI2Pwx9MtJjqLOc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791464610; c=relaxed/simple; bh=VpV0KaD44FbDOc/jXrwmrc0sWLFS4pT8PRkJ2EdDDpA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=VQreyBCCS5m78kTNMndoqGbCdPyeQ4Re/Ieg4Ar7zl4+xAxFUn+2tgRZHpkabXQdGFevVcrayjfheSbgqPamzfiypweziiNB65ju/+VzeBxknLOWmqCvaH70WqYA61Kg7ntNG09JI4HMokcdwKOXKlaqyzMdsnr5kqCtIS11H5w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=p0HfSe4b; arc=none smtp.client-ip=209.85.208.52 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="p0HfSe4b" Received: by mail-ed1-f52.google.com with SMTP id 4fb4d7f45d1cf-6afafc89b48so4689711a12.2 for ; Thu, 08 Oct 2026 06:03:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1791464608; x=1792069408; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to :content-type; bh=+kGI3k/44UlMEz8kQ2oCVgsiUMpT90qi7dL2PUgRNcs=; b=p0HfSe4bmTWV0pcHjzxWrpNbk1Nwcmc9quyoV+qtgcv/R2DoN+8LY5QN3h0CkzMlgY Qze+cK5h6nuI2jo9Lcm48MalOBAupjLg8IxcM/F+l6yxsYBsKmAaI8KXOvse4gUNF3PA NAj7FMX8DRO/Y1xVzhWtIZup3K0XVMyUog/ed+3VC6RO8BaDrJjY3aioYmOEZ7Yx8RYL pzC1N1ogqdB4m6Gd9h7TOC+RpN8uJXS5P7E1Kbw/7pBY+UPIwxeP/yTvyuIcocQ59v7j NsguLluwOg2zy5BiWq+briuHW2zMP2c3JXM0/VD7VRQeprmmnW5eJbNhd4HpMvJt3Ees Iy3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1791464608; x=1792069408; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=+kGI3k/44UlMEz8kQ2oCVgsiUMpT90qi7dL2PUgRNcs=; b=BUiWOl2RZQljeVWOJcs0SXc+h6LOQkYRYha2O25+4F78zce2GMP79N6KLmMPvskzPZ PolN8zs/je1VlbW5fDCDJbz1DZ/imGP8B82FqEKaKrHzgDUxE7MwPq+4H+0XuMkUesc7 SB9HzC7Hy2x/nSTBLzWdo5u5h6mgyzO3PxDEM5F1w0ZxrQ8oDQHih+0wLZjcKbelReBM ntvU8fOvC19HYfWVHqYxUb3jgt+szoeGzv9LRvm/YFbUDqPkSX1+0tPwDK2T8/+R72cp JXJZ9QN4W0RML8MwIGV/fi/7W5xHC4/O2iWATV2rdmnbjn9DYrinKZQQI6TK/h0MskCT S7ag== X-Forwarded-Encrypted: i=1; AKwUvByGrxv3B1tx9E66iClw6vJuaBQM9Sh2/L5Bp5kAoYaXSiEfHUjXXgg+tfi03vwm5LFyI+UfQU0=@vger.kernel.org X-Gm-Message-State: AFq9FYJuGs3FE6zUlv2nGdy6kvKIBF87sfHpjl5PMtrwk6+5MpFZWfG5 pEUCzyYWfAvFJLFCmzx2GC4fRcflTM66IMLzZ8DvcaJ+BO3VXMOeHBtvLcVD7w== X-Gm-Gg: AYBFou0xV7Nm6N/rcC4uaekPg18u49qyDQHGJwkUK9eA72MeEPP7Hn6hYbZJK8EI1xa Kt9nMOEeHD7kZ7lAN66u3GT9bteDe5TpoCD25Id8Bm6MLnRCGmCOlRtQhB5uTzzkl4QRroMrT2h 5wqYntLhpeRBVxEJ5uO6J/sRo1mkGansZum4u7HOfu2kSDzy+rHZhuHQHRcZ6Th9KiXYjoGC3Ji 2zRTt0t1aeHLnUWP/BIGm6kc1YdVEWzs4DrPi0Frzy2NIdlAAemyNhuvomlRYdWQ2MtzxL6aoav Mk7zgYkhYdewGRw0hEa+nhy0TU0Vx9CGK0Hx7jp+UIpZveH7H/5EbZY9wcf9QerjSkv1JE42nqR va9HmDhZlaE1+NYqbaupwE15w17WafrpcwWOy5lc8QmqLzP7YSkksoQnWm22oeMuvedq6SkpvPu 1PeLaTOaykp3ehJWBMLqwf9AZqSvgrHqUDK07SrZ0pAXLuPkdpr/EAwKHVDdXeESJTv7CIDiT2R hIca6/BBEVj107RnXAjJBZMVL49lCxVkiZ7MOP6lEWCu8ZduXk3vXL/wG1xqySNnsTeumbkvd3P bqbZ1rUTW2D5nsiRhhW5NL5iygNbXA1Eb8w7+EIWKdyb3UoCqeeGl3A6xKQ= X-Received: by 2002:a05:6402:278d:b0:6af:5b14:78e7 with SMTP id 4fb4d7f45d1cf-6aff454b592mr5115802a12.34.1791464607322; Thu, 08 Oct 2026 06:03:27 -0700 (PDT) Received: from ?IPV6:2a01:4b00:bd21:4f00:7cc6:d3ca:494:116c? ([2a01:4b00:bd21:4f00:7cc6:d3ca:494:116c]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-6b00aa4c9b8sm1413473a12.37.2026.10.08.06.03.26 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 08 Oct 2026 06:03:26 -0700 (PDT) Message-ID: <36d9e570-15d8-4a2d-aafb-3ee6e5681205@gmail.com> Date: Thu, 8 Oct 2026 14:03:17 +0100 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net v1] net: devmem: prevent mixing fragments from different bindings To: Mina Almasry , Stanislav Fomichev , Paolo Abeni , Kaiyuan Zhang , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Simon Horman , Bobby Eshleman , Ralf Lici References: <20261008033952.1399670-1-almasrymina@google.com> Content-Language: en-US From: Pavel Begunkov In-Reply-To: <20261008033952.1399670-1-almasrymina@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/8/26 04:39, Mina Almasry wrote: > validate_xmit_unreadable_skb() only inspects shinfo->frags[0] and > assumes all fragments in an unreadable skb belong to that same devmem > binding. However, tcp_sendmsg_locked() only checks that readability > matches the presence of a binding (skb_frags_readable(skb) != !binding), > allowing consecutive sendmsg() calls with different dmabuf bindings to > collapse into the same skb and bypass per-device and unbind checks in > validate_xmit_unreadable_skb(). > > Add net_devmem_skb_binding() to query the binding associated with an > skb, reuse it in validate_xmit_unreadable_skb(), and check in > zerocopy_fill_skb_from_devmem() that existing fragments match the target > binding. Looks good Pavel Begunkov -- Pavel Begunkov