From mboxrd@z Thu Jan 1 00:00:00 1970 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=-13.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 8CE7BC43461 for ; Mon, 7 Sep 2020 16:36:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 40D6F21D1A for ; Mon, 7 Sep 2020 16:36:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599496581; bh=TTWkATQ6EXKEp+vAuj7niHV5cTlbg6tkuzwmJGjMVgg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DYQBsrBlPn4FVDHy+erIOremYCDikR68VeVMA4SFNGYDiy4eJEtDcYCTtk0c/JGta zkg4YZS+0UkAbSatdg6N7Va2QzZqqWC+F+dGZwYSlTeL4bmSuICR068IWgV8uMT6RZ SPr+CVUtEfH4B8VXwREepnWPYpTXeKkg3Rzm7VQc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730728AbgIGQgR (ORCPT ); Mon, 7 Sep 2020 12:36:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:46758 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730601AbgIGQdX (ORCPT ); Mon, 7 Sep 2020 12:33:23 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 85C9D21927; Mon, 7 Sep 2020 16:33:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599496403; bh=TTWkATQ6EXKEp+vAuj7niHV5cTlbg6tkuzwmJGjMVgg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HLuisueBvb9gJP9sLQ3kzxDje5f2dxk4nzz82OTbgD16VLnMxgclF6rsIpvQnURZP 9/Jr1v3RAcHBabJDHrTA7lN86Hu3qcoBOtnvsBvIOxpIZozRMLQpWUje8E0JY1kqUC 1KMrc8iRvc1WvSSZM1u1mnTF6mKASAN8mF7tSXX4= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Xie He , Krzysztof Halasa , Martin Schiller , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.8 49/53] drivers/net/wan/hdlc: Change the default of hard_header_len to 0 Date: Mon, 7 Sep 2020 12:32:15 -0400 Message-Id: <20200907163220.1280412-49-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200907163220.1280412-1-sashal@kernel.org> References: <20200907163220.1280412-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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; -- 2.25.1