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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 61ACBC35242 for ; Fri, 14 Feb 2020 06:40:59 +0000 (UTC) Received: from krantz.zx2c4.com (krantz.zx2c4.com [192.95.5.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BBC1E2187F for ; Fri, 14 Feb 2020 06:40:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=posteo.net header.i=@posteo.net 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t=1581662427; bh=BEfaLHXzeG+7LMZ+XpMjNgyvvej6wB0gVJsXgaoYeq4=; h=Subject:To:From:Date:Autocrypt:OpenPGP:From; b=hV/BiGru65+yUM1CEBC8CHa1rik4lrMPEJ51M4z7Z3HWTEuDxG5P1c2Y5XMuDNDNq SBgS++7s0d0Ih4+3+HwkJB+dksXmaizgfDtye557rMlYmkTyOkzip/PQtcUm6dG4hT lPY+692kXAUH7wfow8V4axh8cbeWvcvcp44P+IA3K4ki0eqHSYaFlXLm/I4Xa48UpD 83sFC7Tl9YXjKfd6+n//llQeTS6Z6jp5eElPDVuABF/vTXyP72xhOOCcAfyKD/KSaQ GCmvn+1LLR5I0nHljhgWoHqL4JfTMqsk3oo24+OsHI71fLFWuc4BDfn1soea6AgR7a RqQldPfHkJcaA== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 48JkK65RQ5z9rxG for ; Fri, 14 Feb 2020 07:40:26 +0100 (CET) Subject: Re: [PATCH net] wireguard: device: provide sane limits for mtu setting To: wireguard@lists.zx2c4.com References: <20200214063814.229451-1-edumazet@google.com> From: Quan Zhou Message-ID: Date: Fri, 14 Feb 2020 14:40:23 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:73.0) Gecko/20100101 Thunderbird/73.0 MIME-Version: 1.0 In-Reply-To: <20200214063814.229451-1-edumazet@google.com> Content-Language: en-US Autocrypt: addr=quan@posteo.net; 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to zero? On 2/14/20 14:38, Eric Dumazet wrote: > If wireguard device mtu is set to zero, a divide by zero > crash happens in calculate_skb_padding(). > > This patch provides dev->min_mtu and dev->max_mtu bounds. > > Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") > Signed-off-by: Eric Dumazet > Reported-by: syzbot > Cc: Jason A. Donenfeld > Cc: wireguard@lists.zx2c4.com > --- > drivers/net/wireguard/device.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/net/wireguard/device.c b/drivers/net/wireguard/device.c > index 43db442b1373073eaf5e805cfe6cfee15875437a..c02b84cca122d92ee8a81c5efdcf67aada2554d6 100644 > --- a/drivers/net/wireguard/device.c > +++ b/drivers/net/wireguard/device.c > @@ -271,9 +271,14 @@ static void wg_setup(struct net_device *dev) > dev->features |= WG_NETDEV_FEATURES; > dev->hw_features |= WG_NETDEV_FEATURES; > dev->hw_enc_features |= WG_NETDEV_FEATURES; > + > dev->mtu = ETH_DATA_LEN - MESSAGE_MINIMUM_LENGTH - > sizeof(struct udphdr) - > max(sizeof(struct ipv6hdr), sizeof(struct iphdr)); > + dev->min_mtu = MESSAGE_PADDING_MULTIPLE; > + dev->max_mtu = ETH_MAX_MTU - MESSAGE_MINIMUM_LENGTH - > + sizeof(struct udphdr) - > + max(sizeof(struct ipv6hdr), sizeof(struct iphdr)); > > SET_NETDEV_DEVTYPE(dev, &device_type); > _______________________________________________ WireGuard mailing list WireGuard@lists.zx2c4.com https://lists.zx2c4.com/mailman/listinfo/wireguard