From patchwork Tue Sep 15 14:12:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 309681 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=-15.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 3B662C43461 for ; Tue, 15 Sep 2020 23:22:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC578208E4 for ; Tue, 15 Sep 2020 23:22:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600212174; bh=TTWkATQ6EXKEp+vAuj7niHV5cTlbg6tkuzwmJGjMVgg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=f1SOZq/pVeJEXzNzVaGxlrYrBgE7JA4MXATLob/8qul2wD1orHEV3o4zbXN3Y/WfW h6uR0CSPXl9p3Pbzq80SPMG1ZcAuWlkA8AeqlSm6WlM0ULlYjY5EGim3kjq6it8Fk5 TcAwo4MHv/jwsSEZePnQT4fBSBgV/jzpskFZah/4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727005AbgIOXWU (ORCPT ); Tue, 15 Sep 2020 19:22:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:48014 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727203AbgIOOiG (ORCPT ); Tue, 15 Sep 2020 10:38:06 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F31F922475; Tue, 15 Sep 2020 14:28:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600180086; bh=TTWkATQ6EXKEp+vAuj7niHV5cTlbg6tkuzwmJGjMVgg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zKbH1z7GGnYZNqUb8r7HEGSyGgwQktPp8K/+pPaq39RFlpGE7als0rgMVG1ve5Moc Qv/pghhfnSjYeU8gne729EAf3YtbbnfUanYp82EZZhhrORMTboBjUU9LzkjNvwiJwy Z//GdRSWL6kC4LFDQu+8pldhKoGi6pHUNqimRJ5A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Krzysztof Halasa , Martin Schiller , Xie He , "David S. Miller" , Sasha Levin Subject: [PATCH 5.8 104/177] drivers/net/wan/hdlc: Change the default of hard_header_len to 0 Date: Tue, 15 Sep 2020 16:12:55 +0200 Message-Id: <20200915140658.634720606@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200915140653.610388773@linuxfoundation.org> References: <20200915140653.610388773@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Xie He [ Upstream commit 2b7bcd967a0f5b7ac9bb0c37b92de36e073dd119 ] Change the default value of hard_header_len in hdlc.c from 16 to 0. Currently there are 6 HDLC protocol drivers, among them: hdlc_raw_eth, hdlc_cisco, hdlc_ppp, hdlc_x25 set hard_header_len when attaching the protocol, overriding the default. So this patch does not affect them. hdlc_raw and hdlc_fr don't set hard_header_len when attaching the protocol. So this patch will change the hard_header_len of the HDLC device for them from 16 to 0. This is the correct change because both hdlc_raw and hdlc_fr don't have header_ops, and the code in net/packet/af_packet.c expects the value of hard_header_len to be consistent with header_ops. In net/packet/af_packet.c, in the packet_snd function, for AF_PACKET/DGRAM sockets it would reserve a headroom of hard_header_len and call dev_hard_header to fill in that headroom, and for AF_PACKET/RAW sockets, it does not reserve the headroom and does not call dev_hard_header, but checks if the user has provided a header of length hard_header_len (in function dev_validate_header). Cc: Krzysztof Halasa Cc: Martin Schiller Signed-off-by: Xie He Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/wan/hdlc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wan/hdlc.c b/drivers/net/wan/hdlc.c index 386ed2aa31fd9..9b00708676cf7 100644 --- a/drivers/net/wan/hdlc.c +++ b/drivers/net/wan/hdlc.c @@ -229,7 +229,7 @@ static void hdlc_setup_dev(struct net_device *dev) dev->min_mtu = 68; dev->max_mtu = HDLC_MAX_MTU; dev->type = ARPHRD_RAWHDLC; - dev->hard_header_len = 16; + dev->hard_header_len = 0; dev->needed_headroom = 0; dev->addr_len = 0; dev->header_ops = &hdlc_null_ops;