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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 AAEA0C47094 for ; Mon, 7 Jun 2021 16:24:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79D43613D2 for ; Mon, 7 Jun 2021 16:24:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233622AbhFGQYL (ORCPT ); Mon, 7 Jun 2021 12:24:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:33510 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233104AbhFGQVg (ORCPT ); Mon, 7 Jun 2021 12:21:36 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 540F661883; Mon, 7 Jun 2021 16:15:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623082510; bh=88pIXm3i093tIChz13k6XghCQ0SvYtyMLsDBBea0Woo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eT0xGn3LuJw7baoiJRGfHvxMVyefhNwp6+2jLbje5buShg8mk6TTS/sipzz2uT6f7 r5oP+eamCfKoL4pxy4EMpKEcTsSTqXOGU2Z067VL5+9jhpuKxY1k0Fc6/J2FTcvF2z vhBA8MDMvum3i5iWe3bhPKRM4LYHzCG5RnD6W+1Ga2og08dzihDVN3UVfyN5VL9Jz0 E9Ix3mCF2eyJH+9Is1F4HWlFSfPwUchis87cZgd9zG7sjHG8IIt4vokKxCxrOX6vAA 3HW3pvWHOtcOlDTKBY6Q/zoEP2Ff6+8NOOJnaxv30d40UBOKPG1vUkP1pJB0lg6FhB v1ASpo5/2Afcg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Josh Triplett , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 17/21] net: ipconfig: Don't override command-line hostnames or domains Date: Mon, 7 Jun 2021 12:14:44 -0400 Message-Id: <20210607161448.3584332-17-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210607161448.3584332-1-sashal@kernel.org> References: <20210607161448.3584332-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Josh Triplett [ Upstream commit b508d5fb69c2211a1b860fc058aafbefc3b3c3cd ] If the user specifies a hostname or domain name as part of the ip= command-line option, preserve it and don't overwrite it with one supplied by DHCP/BOOTP. For instance, ip=::::myhostname::dhcp will use "myhostname" rather than ignoring and overwriting it. Fix the comment on ic_bootp_string that suggests it only copies a string "if not already set"; it doesn't have any such logic. Signed-off-by: Josh Triplett Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv4/ipconfig.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c index 88212615bf4c..58719b9635d9 100644 --- a/net/ipv4/ipconfig.c +++ b/net/ipv4/ipconfig.c @@ -866,7 +866,7 @@ static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_d /* - * Copy BOOTP-supplied string if not already set. + * Copy BOOTP-supplied string */ static int __init ic_bootp_string(char *dest, char *src, int len, int max) { @@ -915,12 +915,15 @@ static void __init ic_do_bootp_ext(u8 *ext) } break; case 12: /* Host name */ - ic_bootp_string(utsname()->nodename, ext+1, *ext, - __NEW_UTS_LEN); - ic_host_name_set = 1; + if (!ic_host_name_set) { + ic_bootp_string(utsname()->nodename, ext+1, *ext, + __NEW_UTS_LEN); + ic_host_name_set = 1; + } break; case 15: /* Domain name (DNS) */ - ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain)); + if (!ic_domain[0]) + ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain)); break; case 17: /* Root path */ if (!root_server_path[0]) -- 2.30.2