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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A1787C02185 for ; Sat, 18 Jan 2025 10:09:35 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tZ5la-0005LV-BT; Sat, 18 Jan 2025 05:09:22 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tZ5lY-0005LK-Ac for qemu-devel@nongnu.org; Sat, 18 Jan 2025 05:09:20 -0500 Received: from mail-pl1-x635.google.com ([2607:f8b0:4864:20::635]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1tZ5lW-0008J4-6r for qemu-devel@nongnu.org; Sat, 18 Jan 2025 05:09:19 -0500 Received: by mail-pl1-x635.google.com with SMTP id d9443c01a7336-2161eb94cceso36723835ad.2 for ; Sat, 18 Jan 2025 02:09:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1737194956; x=1737799756; darn=nongnu.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=2opQBsl7rqm5zIKEYdaNZzsCdm10KnWISlLhTd4FScw=; b=QDnBUQOG/0d3upD4xOD44wjpRHIuhd5Tct671Nx+VCTmw+M9CNIjnHkqLqHZf3QYTH T4RSFKaiopzLOvEkfa6oR8rrXs1Tyy/daMYmNkTItBFb3WhwraDmwe54LEODezSWd68r 3Tm2sDwyYXi6/0N0Krkpj+siX/xSqI8GhllKXB6EiC6pxgNGJZqVRiPkuhmlvEcy9sQ7 E/+yxAoJ//i88rt1cBZwjpTdHp6jp3cha0yLbc7BN/u+5GgdlAhfixPd7pT1SBhq+34C XpwhXw7H7ENgm5/IJT3LlrNUnEjYdHyLZVsKD7m/pjXqdY6gnI32dgp+Gf9aAOc2R9oA CKpw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737194956; x=1737799756; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=2opQBsl7rqm5zIKEYdaNZzsCdm10KnWISlLhTd4FScw=; b=NR2UPqy+ajW9nj0heGL4JCdcFn/ISOHk5SwvH7acZK7e+swRn95mAz2gfIQWuRqrbV Kdj1GKCrmLT2+WhifZpaHZ4Bg1Zk33HXg/8vwlQdxKufNlhEyE7fAFpMclv1QV2HnLqI NQ5ZPn18RWwGM66WeZZP6YHk4+NWak2dfCcv1lbJiWxJSxY3KpeoLhvnqXkCjIOJVS6Q ehe09HjN97KaFpFBmNn2YS+QbpwOURE935VF/CfY++ExdKUorfN5rdZ5yfLUEpyNJRkZ wLFTW9HvAquLNw/QI+2jtadLxLvw72+nTBiHx86yhbi0YNKjauRUcIPpoBE1/+5QNzvG dBDQ== X-Forwarded-Encrypted: i=1; AJvYcCUHmeYpFEijlwFcV3VG/GcIPhIkmgZXFiZHU1OinQFmA+Fe+jcrPlmq2l4DE6G3o4BODVzTziwOdeqO@nongnu.org X-Gm-Message-State: AOJu0Ywdh/pOkhWohr+81FR+SSBlKyK9Bss2JMA+ZvSJNNd+/gZMTU4e +J3KCp1N/85dTzd9kcB8rusBMYSFMyMGcRNn2qG9UiZt4tFknSrJHNxO4faQ X-Gm-Gg: ASbGncvcA8My1yfH19cfA1c0hm9gOVdzRYhaz0ixHnobqocymMCTRNFoQzybDUyg+bv NInR0W+uawuuG6lrrmQX59moCPZEESMj7Xqh11S4oKc0JPbvFpHZQLPtzq3n0J9i7FuGPFRK6rr lYosRgcqlGXMvq9+ApoGflMYhC8NSNWUMMW5fEAJM04hIFj8twJPUGhTmKULJGHc2D9RwXpIPta ZqHrOkXssNlpWYfafosNB8uL9uOyMaPefW0iauPM8jrOsT0j9yNwyEz+ZGWHq6yQNthG7bHQSa5 2w== X-Google-Smtp-Source: AGHT+IHe/YtWpwNDmPwJEDsxusye9QgmUSuolWE5/AuqR00N9cXJkgJq1XVYm7dadgHBrU8mK5dbGA== X-Received: by 2002:a17:902:ce01:b0:212:63c0:d9e7 with SMTP id d9443c01a7336-21c34cc00f8mr86131785ad.0.1737194956298; Sat, 18 Jan 2025 02:09:16 -0800 (PST) Received: from [10.4.77.176] ([118.103.63.141]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21c2d3a87e4sm29221515ad.111.2025.01.18.02.09.14 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 18 Jan 2025 02:09:16 -0800 (PST) Message-ID: <0e59f286-15d1-426a-8012-0370b07f149c@gmail.com> Date: Sat, 18 Jan 2025 19:09:13 +0900 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] net: Fix announce_self To: Laurent Vivier , qemu-devel@nongnu.org Cc: Jason Wang References: <20250117111709.970789-1-lvivier@redhat.com> <20250117111709.970789-2-lvivier@redhat.com> Content-Language: en-US From: Akihiko Odaki In-Reply-To: <20250117111709.970789-2-lvivier@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=2607:f8b0:4864:20::635; envelope-from=akihiko.odaki@gmail.com; helo=mail-pl1-x635.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 2025/01/17 20:17, Laurent Vivier wrote: > b9ad513e1876 ("net: Remove receive_raw()") adds an iovec entry > in qemu_deliver_packet_iov() to add the virtio-net header > in the data when QEMU_NET_PACKET_FLAG_RAW is set but forgets > to increase the number of iovec entries in the array, so > receive_iov() will only send the first entry (the virtio-net > entry, full of 0) and no data. The packet will be discarded. > > The only user of QEMU_NET_PACKET_FLAG_RAW is announce_self. > > We can see the problem with tcpdump: > > - QEMU parameters: > > .. -monitor stdio \ > -netdev bridge,id=netdev0,br=virbr0 \ > -device virtio-net,mac=9a:2b:2c:2d:2e:2f,netdev=netdev0 \ > > - HMP command: > > (qemu) announce_self > > - TCP dump: > > $ sudo tcpdump -nxi virbr0 > > without the fix: > > > > with the fix: > > ARP, Reverse Request who-is 9a:2b:2c:2d:2e:2f tell 9a:2b:2c:2d:2e:2f, length 46 > 0x0000: 0001 0800 0604 0003 9a2b 2c2d 2e2f 0000 > 0x0010: 0000 9a2b 2c2d 2e2f 0000 0000 0000 0000 > 0x0020: 0000 0000 0000 0000 0000 0000 0000 > > Reported-by: Xiaohui Li > Bug: https://issues.redhat.com/browse/RHEL-73891 > Fixes: b9ad513e1876 ("net: Remove receive_raw()") > Cc: akihiko.odaki@daynix.com > Signed-off-by: Laurent Vivier Thanks for finding out this bug: Reviewed-by: Akihiko Odaki I believe this should have: Cc: qemu-stable@nongnu.org > --- > net/net.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/net/net.c b/net/net.c > index c1bb19a52373..9cded70dde74 100644 > --- a/net/net.c > +++ b/net/net.c > @@ -822,6 +822,7 @@ static ssize_t qemu_deliver_packet_iov(NetClientState *sender, > iov_copy[0].iov_len = nc->vnet_hdr_len; > memcpy(&iov_copy[1], iov, iovcnt * sizeof(*iov)); > iov = iov_copy; > + iovcnt++; > } > > if (nc->info->receive_iov) {