From patchwork Wed Jan 8 21:16:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Fastabend X-Patchwork-Id: 1219979 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="QqoQBK2b"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 47tMVw3R9pz9sP6 for ; Thu, 9 Jan 2020 08:16:24 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727063AbgAHVQY (ORCPT ); Wed, 8 Jan 2020 16:16:24 -0500 Received: from mail-il1-f193.google.com ([209.85.166.193]:37214 "EHLO mail-il1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726836AbgAHVQY (ORCPT ); Wed, 8 Jan 2020 16:16:24 -0500 Received: by mail-il1-f193.google.com with SMTP id t8so3908506iln.4; Wed, 08 Jan 2020 13:16:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:from:to:cc:date:message-id:in-reply-to:references :user-agent:mime-version:content-transfer-encoding; bh=m8Rchxp7WynrVrNQW7gz1KcCJvgeZh/2BETow1fq1Bo=; b=QqoQBK2bwdHuoMAaimQOxerVbNsi3Px0z5fL7uQStVjOYFThjmYpGsflbYQ8WpzBA9 qlqk9seUe0pi1gaoOGZ921XYu6osXCCnFLeZIuEE3AeIhO+g0P7azgC67qcOsYAs4EbY uIshlgN+ptvIT1ZjyEreSn2LnBc0Dl1vF+kZ5NVcfhbcGx6NFN+/ECqVK/8gTOW3nmDa R2i56OKSSoySGNKLUK5CaByP8VRZ/akk1wmeyC7WL5GMawgew8dcIzId/A3CaOhLdUPo l+3nggYaJmX6zt3qaymCWhc32I/tZRnjXki49E5qwkcwsuoL8E5eX7RDNb/sAUGl3DBI WtYA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:date:message-id:in-reply-to :references:user-agent:mime-version:content-transfer-encoding; bh=m8Rchxp7WynrVrNQW7gz1KcCJvgeZh/2BETow1fq1Bo=; b=HBbtowahChIcy9DRF7g24lErfy0+QwB+iPEdr/rzIcBGd6gD7We1pqjjK4t8NqCpS8 SS8VozMSccZzZ7eYgj4zxdEk7eI+Y5fN/5COv9vrQEQIPF/1UqeACOW8AlaHnpf6Defi 5BQk0MsYpRKXMTt3S487hvbz0Kg2xTDa1tFqkSuBd9mLgZkl3/n8Hp2JWUMmGl+pAgy6 MB5JsFLjpDkrlmbk3oKWFxWaQKpvwjGmpUQ3R6c1tzGmVJuWLL3EJ9mvXmQX52nKqg2P kImxkxbsFhmR9kWrAYRQsRNU+5uxZV7zzeQ7KMZLHAqVs2yznjGZT5RG5vzpdvpry6aw ugVA== X-Gm-Message-State: APjAAAVSZEvDkV3QdLvquZFT+ouze3VY3moXUhWwDiUqNk2n1B0KPKvS pS94Yi4muSwuoD1JqU1eEvjDYEp5 X-Google-Smtp-Source: APXvYqzr/9d+tadjw2nMeNKOAHWft++tJnwtK6W4m0lHXF08zQkV8JkIWyv+pnuzwuKNBpbmcl/NpA== X-Received: by 2002:a92:d5cf:: with SMTP id d15mr5490293ilq.306.1578518183266; Wed, 08 Jan 2020 13:16:23 -0800 (PST) Received: from [127.0.1.1] ([184.63.162.180]) by smtp.gmail.com with ESMTPSA id i13sm903229ioi.67.2020.01.08.13.16.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 08 Jan 2020 13:16:22 -0800 (PST) Subject: [bpf PATCH 8/9] bpf: sockmap/tls, tls_push_record can not handle zero length skmsg From: John Fastabend To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, john.fastabend@gmail.com, ast@kernel.org, daniel@iogearbox.net Date: Wed, 08 Jan 2020 21:16:11 +0000 Message-ID: <157851817088.1732.14988301389495595092.stgit@ubuntu3-kvm2> In-Reply-To: <157851776348.1732.12600714815781177085.stgit@ubuntu3-kvm2> References: <157851776348.1732.12600714815781177085.stgit@ubuntu3-kvm2> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org When passed a zero length skmsg tls_push_record() causes a NULL ptr deref. To resolve for fixes do a simple length check at start of routine. To create this case a user can create a BPF program to pop all the data off the message then return SK_PASS. Its not a very practical or useful thing to do so we mark it unlikely. Fixes: d3b18ad31f93d ("tls: add bpf support to sk_msg handling") Signed-off-by: John Fastabend --- net/tls/tls_sw.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 21c7725d17ca..0326e916ab01 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -680,6 +680,9 @@ static int tls_push_record(struct sock *sk, int flags, msg_pl = &rec->msg_plaintext; msg_en = &rec->msg_encrypted; + if (unlikely(!msg_pl->sg.size)) + return 0; + split_point = msg_pl->apply_bytes; split = split_point && split_point < msg_pl->sg.size; if (unlikely((!split &&