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=-19.0 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 BC0E8C433B4 for ; Mon, 12 Apr 2021 16:26:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99B54613AF for ; Mon, 12 Apr 2021 16:26:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244530AbhDLQ0T (ORCPT ); Mon, 12 Apr 2021 12:26:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:56430 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243653AbhDLQYJ (ORCPT ); Mon, 12 Apr 2021 12:24:09 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5095261357; Mon, 12 Apr 2021 16:23:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1618244631; bh=urUcjILkYHjEd6w7EKb//ZTXipxCqZDV1mRx4Z2JcoE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qKkUtrd8OZ4xGwiG21qBYwEscQwmJ2f5BeXCVH5PUujWFXgVB7RzxtB/au9CmA24a /oaZVwi62gL5Kq7aZAhz9xwmEQQ26WHPeFzMfutChR8OxdilHTAZzeIE8GPSEeMaIv Y1gdY19Fpu6tA500uxePHVTrUvOkhLZb8v3DB1M2DbOgAFKFThIGrwyibBJvepQkRU a5xWMzfcro+3YoYuTaTch0uP1QM4OZz1ct3g+rR5il5KvpGytFO4ap2MEhu8XzCsnU K2Z2bJviGZrQKWOBXzokJlOC26IyzyZR+W+p8JnD8pVUtlk3aKtoNLHiVN0qY1+R0w M/q2nksG406tQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Phillip Potter , syzbot+001516d86dbe88862cec@syzkaller.appspotmail.com, Eric Dumazet , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.11 44/51] net: tun: set tun->dev->addr_len during TUNSETLINK processing Date: Mon, 12 Apr 2021 12:22:49 -0400 Message-Id: <20210412162256.313524-44-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210412162256.313524-1-sashal@kernel.org> References: <20210412162256.313524-1-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: Phillip Potter [ Upstream commit cca8ea3b05c972ffb5295367e6c544369b45fbdd ] When changing type with TUNSETLINK ioctl command, set tun->dev->addr_len to match the appropriate type, using new tun_get_addr_len utility function which returns appropriate address length for given type. Fixes a KMSAN-found uninit-value bug reported by syzbot at: https://syzkaller.appspot.com/bug?id=0766d38c656abeace60621896d705743aeefed51 Reported-by: syzbot+001516d86dbe88862cec@syzkaller.appspotmail.com Diagnosed-by: Eric Dumazet Signed-off-by: Phillip Potter Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/tun.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 5512418b7be0..2ed54818dcbc 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -69,6 +69,14 @@ #include #include #include +#include +#include +#include +#include +#include +#include +#include +#include #include #include @@ -2925,6 +2933,45 @@ static int tun_set_ebpf(struct tun_struct *tun, struct tun_prog __rcu **prog_p, return __tun_set_ebpf(tun, prog_p, prog); } +/* Return correct value for tun->dev->addr_len based on tun->dev->type. */ +static unsigned char tun_get_addr_len(unsigned short type) +{ + switch (type) { + case ARPHRD_IP6GRE: + case ARPHRD_TUNNEL6: + return sizeof(struct in6_addr); + case ARPHRD_IPGRE: + case ARPHRD_TUNNEL: + case ARPHRD_SIT: + return 4; + case ARPHRD_ETHER: + return ETH_ALEN; + case ARPHRD_IEEE802154: + case ARPHRD_IEEE802154_MONITOR: + return IEEE802154_EXTENDED_ADDR_LEN; + case ARPHRD_PHONET_PIPE: + case ARPHRD_PPP: + case ARPHRD_NONE: + return 0; + case ARPHRD_6LOWPAN: + return EUI64_ADDR_LEN; + case ARPHRD_FDDI: + return FDDI_K_ALEN; + case ARPHRD_HIPPI: + return HIPPI_ALEN; + case ARPHRD_IEEE802: + return FC_ALEN; + case ARPHRD_ROSE: + return ROSE_ADDR_LEN; + case ARPHRD_NETROM: + return AX25_ADDR_LEN; + case ARPHRD_LOCALTLK: + return LTALK_ALEN; + default: + return 0; + } +} + static long __tun_chr_ioctl(struct file *file, unsigned int cmd, unsigned long arg, int ifreq_len) { @@ -3088,6 +3135,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; } tun->dev->type = (int) arg; + tun->dev->addr_len = tun_get_addr_len(tun->dev->type); netif_info(tun, drv, tun->dev, "linktype set to %d\n", tun->dev->type); call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, -- 2.30.2