From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 138001DC9B8 for ; Thu, 16 Jan 2025 08:08:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=140.211.166.136 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737014940; cv=none; b=cKvm3yH5FAFpVyEH4qRxM+W9lzIEWJXgpRBzp8ybKppjY91ZSULVq6jdD9jn/fFhgwe0HYS0i+DWU5Odf1Ly9cE6PO19rAH8PmosjIGWgX7ZIrhLGgMWpd/+3G68BfpTxEpv/YA6yQrl+EeYPA+IkxMeWrDjncCbPER6E7CeoXk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737014940; c=relaxed/simple; bh=GaoqUecKAtyQ+qguYmr90B1yeZ/UsTWOKRqkOYcnF54=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To; b=kNV4pgdPZpumSWxQwy2cWs4JBRRmuwRhJeyObcVjEu33cwKOSF9aRVBb425X7I4inBfhaCyiSOleqsOxjoOA/0dMy2YFGyoJSmGxxVsCkCDeIdFC2QNfgPX5pYwA5EjJQ6tVHpuLVwdYXUYKK6ciy1IzU0nWvPq203U9XmqF8Aw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=daynix-com.20230601.gappssmtp.com header.i=@daynix-com.20230601.gappssmtp.com header.b=0duCGvrS; arc=none smtp.client-ip=140.211.166.136 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=daynix-com.20230601.gappssmtp.com header.i=@daynix-com.20230601.gappssmtp.com header.b="0duCGvrS" Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id C0BBF6FA49 for ; Thu, 16 Jan 2025 08:08:58 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org X-Spam-Flag: NO X-Spam-Score: -1.9 X-Spam-Level: Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id GrEu_zthFt54 for ; Thu, 16 Jan 2025 08:08:56 +0000 (UTC) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=2607:f8b0:4864:20::62a; helo=mail-pl1-x62a.google.com; envelope-from=akihiko.odaki@daynix.com; receiver= DMARC-Filter: OpenDMARC Filter v1.4.2 smtp3.osuosl.org EA6D76FA41 Authentication-Results: smtp3.osuosl.org; dmarc=none (p=none dis=none) header.from=daynix.com DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org EA6D76FA41 Authentication-Results: smtp3.osuosl.org; dkim=pass (2048-bit key) header.d=daynix-com.20230601.gappssmtp.com header.i=@daynix-com.20230601.gappssmtp.com header.a=rsa-sha256 header.s=20230601 header.b=0duCGvrS Received: from mail-pl1-x62a.google.com (mail-pl1-x62a.google.com [IPv6:2607:f8b0:4864:20::62a]) by smtp3.osuosl.org (Postfix) with ESMTPS id EA6D76FA41 for ; Thu, 16 Jan 2025 08:08:55 +0000 (UTC) Received: by mail-pl1-x62a.google.com with SMTP id d9443c01a7336-21644aca3a0so12958325ad.3 for ; Thu, 16 Jan 2025 00:08:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=daynix-com.20230601.gappssmtp.com; s=20230601; t=1737014935; x=1737619735; darn=lists.linux-foundation.org; h=to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=Sr3AZgpAWe/4VnOS/hnlHnXvPWA7Ea0pV5fu0VlMHbQ=; b=0duCGvrShRRpkKHX0iRep1DiYzzlKO1A+FQIIMIyLiFsM9JirXnBuH8EAMxGt7a5No 5MUKolTtVp6mqeLLBCq0OzuwFwuq5U5nMQ4E3Ew7gMH6HFb2/Hw/9KpOO/AS3denTybj 4T5oeNx03Yw5cY2MvAw2W/hSNbuizvJF0rSWsUL4+KchRZXt/fur2cyqAXnE3Tf3V1xR PNdQf/5td/jy3B12XSKdT6G8YbjVL6H1+XOFmxLcRJetm5m3MqKYCJl8zk0M+LJ+XrRh fZkieWOol8M5lzPhJLbH12fhc0+Rxb+0aqa/yFi7uvcfmmp84snyEdYkdZFhkhA8CMHp oDRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737014935; x=1737619735; h=to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Sr3AZgpAWe/4VnOS/hnlHnXvPWA7Ea0pV5fu0VlMHbQ=; b=MjoLvI8n+A4+iXpFclRr2puuUFP6+J9EmVjrmbD3RG3baMZo5SsVXe/tM7rmSWpJzr SNN7zcx9asXb7bnMffi8tX09DY/Pf68fEGvEFZzZfu/7D5lXFovQOtz/z/ZeHzaHzAwB OwgqDH1um6KRbpGllMnL9ZAIYt4SiaZinGYJoCStF0IDf5R4HJkXhyCwaFzTEO/d4kxG 1HgOQW89L0OpJhgKn5RS1g8T1t+OzWGuin6LnjInJttdCJLRspFDhsHHPnUb1cDDm27r yy2yv3LL1Xd9PzKzA9Sfp5WtWrgoa5aNzgjtfXj+RW38r7xZAdTX5rk7yyxOrGGmN925 l9Tw== X-Forwarded-Encrypted: i=1; AJvYcCXsObEKP3dOcAO/t5m6vKhNsd6Vc7YPt87A6IHsnqxT3cDFohtNyWCmaw3MApxSh0C0SUwmK1RL71/d0Ukakg==@lists.linux-foundation.org X-Gm-Message-State: AOJu0YyD6n6ojG8rPVvPSDRTS+ONmM8byPvhxrLs5Ct9XUYTrImFhfWL y1EwMsgchF1cR2gaNlAoL/gxl/r/l0w9SsNCjbyzYxbSLU4DBY3JgHQEr4CXQN8= X-Gm-Gg: ASbGncuYn2QHJq2niinJPsqpWSHEO64EmPy8/ub7DAoXjvEM6oW1/XwwxlUeFMgZB2B pA2ppGz2CpwZzxNmR94FSDjf6Eflp0Ctw7GQBCrBeRbAkg1kOuwQ+1wuCqd9EhX/431LmU+4BsR d21DWJuntISoM+nQl7j8PePkCWHjrl1OjyBcQncImvSHlcW9IeItatw2vymEbUy03Q1YYUz7Xi1 /HG1gDcgaYrc9ndGTqWsnaNzyoQR/MC4mPnhCn+zoxq4ojEd1uMLS71S/8= X-Google-Smtp-Source: AGHT+IHS/tQI+KZgiPpOBaU0C7Tuw2h4kHEXmyIHIVzfFUu8R974PCCRg9snVdH9CSEC/VT7pq33OQ== X-Received: by 2002:a17:903:1c8:b0:215:30d1:36fa with SMTP id d9443c01a7336-21a83ffbe2dmr449801035ad.39.1737014935205; Thu, 16 Jan 2025 00:08:55 -0800 (PST) Received: from localhost ([157.82.203.37]) by smtp.gmail.com with UTF8SMTPSA id d9443c01a7336-21a9f13e9e7sm92600955ad.101.2025.01.16.00.08.49 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 16 Jan 2025 00:08:54 -0800 (PST) From: Akihiko Odaki Date: Thu, 16 Jan 2025 17:08:06 +0900 Subject: [PATCH net v3 3/9] tun: Keep hdr_len in tun_get_user() Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20250116-tun-v3-3-c6b2871e97f7@daynix.com> References: <20250116-tun-v3-0-c6b2871e97f7@daynix.com> In-Reply-To: <20250116-tun-v3-0-c6b2871e97f7@daynix.com> To: Jonathan Corbet , Willem de Bruijn , Jason Wang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "Michael S. Tsirkin" , Xuan Zhuo , Shuah Khan , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-kselftest@vger.kernel.org, Yuri Benditovich , Andrew Melnychenko , Stephen Hemminger , gur.stavi@huawei.com, devel@daynix.com, Akihiko Odaki X-Mailer: b4 0.14-dev-fd6e3 hdr_len is repeatedly used so keep it in a local variable. Signed-off-by: Akihiko Odaki --- drivers/net/tun.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index bd272b4736fb..ec56ac865848 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1746,6 +1746,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, struct virtio_net_hdr gso = { 0 }; int good_linear; int copylen; + int hdr_len = 0; bool zerocopy = false; int err; u32 rxhash = 0; @@ -1776,6 +1777,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (tun16_to_cpu(tun, gso.hdr_len) > iov_iter_count(from)) return -EINVAL; + hdr_len = tun16_to_cpu(tun, gso.hdr_len); iov_iter_advance(from, vnet_hdr_sz - sizeof(gso)); } @@ -1783,8 +1785,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if ((tun->flags & TUN_TYPE_MASK) == IFF_TAP) { align += NET_IP_ALIGN; - if (unlikely(len < ETH_HLEN || - (gso.hdr_len && tun16_to_cpu(tun, gso.hdr_len) < ETH_HLEN))) + if (unlikely(len < ETH_HLEN || (hdr_len && hdr_len < ETH_HLEN))) return -EINVAL; } @@ -1797,9 +1798,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, * enough room for skb expand head in case it is used. * The rest of the buffer is mapped from userspace. */ - copylen = gso.hdr_len ? tun16_to_cpu(tun, gso.hdr_len) : GOODCOPY_LEN; - if (copylen > good_linear) - copylen = good_linear; + copylen = min(hdr_len ? hdr_len : GOODCOPY_LEN, good_linear); linear = copylen; iov_iter_advance(&i, copylen); if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS) @@ -1820,10 +1819,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, } else { if (!zerocopy) { copylen = len; - if (tun16_to_cpu(tun, gso.hdr_len) > good_linear) - linear = good_linear; - else - linear = tun16_to_cpu(tun, gso.hdr_len); + linear = min(hdr_len, good_linear); } if (frags) { -- 2.47.1