From patchwork Thu Jan 16 08:08:08 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Akihiko Odaki X-Patchwork-Id: 13941425 Received: from mail-pl1-f178.google.com (mail-pl1-f178.google.com [209.85.214.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4119219CC39 for ; Thu, 16 Jan 2025 08:09:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.178 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737014955; cv=none; b=bhHLODg5WbUhyzvTazigwm70c0uVMmx40eEqZY3L5ld6YQKXiSNG6F1AEoR39BQfLtI5fntmyd0zbD/fDAXC8L2+5cYrmVbIkJfA/WtBwBWHo3cBD5ym1SF9+JU+jbgkeg0hMnqMUMpUaXmAjcWYaU7Qcdf1nO4SkZidKUkUsho= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737014955; c=relaxed/simple; bh=dlMaXnHmVF0I2Zg/+PIxqJ41UeI7IEme3DeBp0QrHII=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To; b=LT5Y/2N9+b8/I7UmyQHyHPCoXl4Fiax0PA2zB3TlJszU2KFPgdZiyxbvm4EmbtX9JPq7oU26++i2R5zCxZ9zk3o9+qM5SFYk9b7XRjO2wd7kRZ2turDKW1ZJX7tIImM43R+oeM6xRclPv3WaX+8a0gQvcpvsN90s0hrjAU2sVJw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=daynix.com; spf=pass smtp.mailfrom=daynix.com; dkim=pass (2048-bit key) header.d=daynix-com.20230601.gappssmtp.com header.i=@daynix-com.20230601.gappssmtp.com header.b=YswuUOdB; arc=none smtp.client-ip=209.85.214.178 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=daynix.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=daynix.com 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="YswuUOdB" Received: by mail-pl1-f178.google.com with SMTP id d9443c01a7336-21670dce0a7so13196025ad.1 for ; Thu, 16 Jan 2025 00:09:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=daynix-com.20230601.gappssmtp.com; s=20230601; t=1737014952; x=1737619752; darn=vger.kernel.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=NTB21hQ3QbIZ1GVa5XRt1Vyvjby7SpDJyzR3ERjrdhY=; b=YswuUOdBiA6KlOkE2kvdBZGT0+JRCmxcB5ZPtBn8DnfoNA3D0StIve12DlPHrdWqs1 bQXEwAAVyB1JFDX7clMvvb3CoSuIhQqifOH4xC6BP84SAXWjgpy2+doBEfycZQkgIArz WlVVhMNZxcfEzrkb20y3mULOx1td7CYd0d0eZjJx9s6oTf3WorlAgesfArUWCbwI9ey+ wuTTzbVwWs5dmwRVSPHEgV9Bxj+sUHZw8AOr6XMUlVHizi6NltGXDl2J/eCU4npEW1U6 YDtFrROmIEQd2Gu5ZgA0bCBWm/tmY7UgCq6ikBtMNi5mdKJP22oyhKqCfgyBItV+AbMH izSQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737014952; x=1737619752; 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=NTB21hQ3QbIZ1GVa5XRt1Vyvjby7SpDJyzR3ERjrdhY=; b=DsJj8Ca6JKtm40f9GDbz8sK711avwgT6oM1Ytfqtz+cT/ekNtUkIuSgIhAOp8vEFfp VY23pUwW8gC5pl8+Vd1dBU3vOCdhGYhZAx1eRMXkFH7BJ507JdfU3yZYbptMGDLtYv7I gGdzPY6Iq8W9xw03VzMzC1jpwBzMqdR29tlRtUGGbXNYlrOa0akh01ULxz4TgI1ncbl3 qGV6l1PdEP85vCUhfKvGZvs95GvqhjO8SCLC56xTsnW3Td0QWcZ+9xVdYQ3x+qvAvXYH O+21q8sJEFG5KGZ4dF0ycJSkf5/G4GV26TfIcUfRUhkxkLjuADU7WPx/es5regsY2POy g9UQ== X-Forwarded-Encrypted: i=1; AJvYcCWP6rOhuEMlKVyd6PVc8NhVnbEFCWcSjdKNlhh2hTcfdChuzmvcft+B7DuZGGL/WVBtgvg=@vger.kernel.org X-Gm-Message-State: AOJu0YzLy8NwMAyvA5R3360d7IsKQ3BKOG5pdoCbneeAZ9pslj+nPlHV tmq3Ip3OuDuCPRHtqrpMMfi6tOa7jo9kMkMH1p7PIqAihOiS+b9G3cbCXbXEazQ= X-Gm-Gg: ASbGncsM259uvAB+Bnm7LcmLGLUS/xPT3+k5rY7NsUICf/td7FXlo0WqKt8oKzv6mVB bC7o+bXN6BHIIgCZ3cHBrYVy4Zl25iEwJnqE5SG/EoSjTSIBVG10+0SCtoOISKceNK1ZW9d/Z+r ajfDSHcNpI3UTB4HDFHAFeImg9zrJ2cxUim65DkMopqG0jNq4h1idE4fA6AJzm1GLMOTWIbTGH+ ou+QgOb6YSVHx7pjiLjXEGOX7ucEE8mVw1WOGj2qZdx4+BD94Cv6MbfJ7I= X-Google-Smtp-Source: AGHT+IGyfHvFQkE+nB1o/CJ0GNwG1fqSgXmY086Vq0Qo1fUXVryET5W7oD5W9XOC903obMvquEVrHw== X-Received: by 2002:a05:6a00:418e:b0:727:3b77:4174 with SMTP id d2e1a72fcca58-72d22032685mr46595151b3a.23.1737014951264; Thu, 16 Jan 2025 00:09:11 -0800 (PST) Received: from localhost ([157.82.203.37]) by smtp.gmail.com with UTF8SMTPSA id 41be03b00d2f7-a31d5da4f97sm10774264a12.55.2025.01.16.00.09.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 16 Jan 2025 00:09:10 -0800 (PST) From: Akihiko Odaki Date: Thu, 16 Jan 2025 17:08:08 +0900 Subject: [PATCH net v3 5/9] tun: Decouple vnet handling Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250116-tun-v3-5-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 Decouple the vnet handling code so that we can reuse it for tap. Signed-off-by: Akihiko Odaki --- drivers/net/tun.c | 229 +++++++++++++++++++++++++++++++----------------------- 1 file changed, 133 insertions(+), 96 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index add09dfdada5..1f4a066ad2f0 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -351,6 +351,122 @@ static inline __virtio16 cpu_to_tun16(unsigned int flags, u16 val) return __cpu_to_virtio16(tun_is_little_endian(flags), val); } +static long tun_vnet_ioctl(int *sz, unsigned int *flags, + unsigned int cmd, int __user *sp) +{ + int s; + + switch (cmd) { + case TUNGETVNETHDRSZ: + s = *sz; + if (put_user(s, sp)) + return -EFAULT; + return 0; + + case TUNSETVNETHDRSZ: + if (get_user(s, sp)) + return -EFAULT; + if (s < (int)sizeof(struct virtio_net_hdr)) + return -EINVAL; + + *sz = s; + return 0; + + case TUNGETVNETLE: + s = !!(*flags & TUN_VNET_LE); + if (put_user(s, sp)) + return -EFAULT; + return 0; + + case TUNSETVNETLE: + if (get_user(s, sp)) + return -EFAULT; + if (s) + *flags |= TUN_VNET_LE; + else + *flags &= ~TUN_VNET_LE; + return 0; + + case TUNGETVNETBE: + return tun_get_vnet_be(*flags, sp); + + case TUNSETVNETBE: + return tun_set_vnet_be(flags, sp); + + default: + return -EINVAL; + } +} + +static int tun_vnet_hdr_get(int sz, unsigned int flags, struct iov_iter *from, + struct virtio_net_hdr *hdr) +{ + if (iov_iter_count(from) < sz) + return -EINVAL; + + if (!copy_from_iter_full(hdr, sizeof(*hdr), from)) + return -EFAULT; + + if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && + tun16_to_cpu(flags, hdr->csum_start) + tun16_to_cpu(flags, hdr->csum_offset) + 2 > tun16_to_cpu(flags, hdr->hdr_len)) + hdr->hdr_len = cpu_to_tun16(flags, tun16_to_cpu(flags, hdr->csum_start) + tun16_to_cpu(flags, hdr->csum_offset) + 2); + + if (tun16_to_cpu(flags, hdr->hdr_len) > iov_iter_count(from)) + return -EINVAL; + + iov_iter_advance(from, sz - sizeof(*hdr)); + + return tun16_to_cpu(flags, hdr->hdr_len); +} + +static int tun_vnet_hdr_put(int sz, struct iov_iter *iter, + const struct virtio_net_hdr *hdr) +{ + if (unlikely(iov_iter_count(iter) < sz)) + return -EINVAL; + + if (unlikely(copy_to_iter(hdr, sizeof(*hdr), iter) != sizeof(*hdr))) + return -EFAULT; + + iov_iter_advance(iter, sz - sizeof(*hdr)); + + return 0; +} + +static int tun_vnet_hdr_to_skb(unsigned int flags, struct sk_buff *skb, + const struct virtio_net_hdr *hdr) +{ + return virtio_net_hdr_to_skb(skb, hdr, tun_is_little_endian(flags)); +} + +static int tun_vnet_hdr_from_skb(unsigned int flags, + const struct net_device *dev, + const struct sk_buff *skb, + struct virtio_net_hdr *hdr) +{ + int vlan_hlen = skb_vlan_tag_present(skb) ? VLAN_HLEN : 0; + + if (virtio_net_hdr_from_skb(skb, hdr, + tun_is_little_endian(flags), true, + vlan_hlen)) { + struct skb_shared_info *sinfo = skb_shinfo(skb); + + if (net_ratelimit()) { + netdev_err(dev, "unexpected GSO type: 0x%x, gso_size %d, hdr_len %d\n", + sinfo->gso_type, tun16_to_cpu(flags, hdr->gso_size), + tun16_to_cpu(flags, hdr->hdr_len)); + print_hex_dump(KERN_ERR, "tun: ", + DUMP_PREFIX_NONE, + 16, 1, skb->head, + min(tun16_to_cpu(flags, hdr->hdr_len), 64), true); + } + WARN_ON_ONCE(1); + return -EINVAL; + } + + return 0; +} + static inline u32 tun_hashfn(u32 rxhash) { return rxhash & TUN_MASK_FLOW_ENTRIES; @@ -1763,22 +1879,10 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (tun->flags & IFF_VNET_HDR) { int vnet_hdr_sz = READ_ONCE(tun->vnet_hdr_sz); - int flags = tun->flags; - - if (iov_iter_count(from) < vnet_hdr_sz) - return -EINVAL; - - if (!copy_from_iter_full(&gso, sizeof(gso), from)) - return -EFAULT; - if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && - tun16_to_cpu(flags, gso.csum_start) + tun16_to_cpu(flags, gso.csum_offset) + 2 > tun16_to_cpu(flags, gso.hdr_len)) - gso.hdr_len = cpu_to_tun16(flags, tun16_to_cpu(flags, gso.csum_start) + tun16_to_cpu(flags, gso.csum_offset) + 2); - - if (tun16_to_cpu(flags, gso.hdr_len) > iov_iter_count(from)) - return -EINVAL; - hdr_len = tun16_to_cpu(flags, gso.hdr_len); - iov_iter_advance(from, vnet_hdr_sz - sizeof(gso)); + hdr_len = tun_vnet_hdr_get(vnet_hdr_sz, tun->flags, from, &gso); + if (hdr_len < 0) + return hdr_len; } len = iov_iter_count(from); @@ -1854,7 +1958,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, } } - if (virtio_net_hdr_to_skb(skb, &gso, tun_is_little_endian(tun->flags))) { + if (tun_vnet_hdr_to_skb(tun->flags, skb, &gso)) { atomic_long_inc(&tun->rx_frame_errors); err = -EINVAL; goto free_skb; @@ -2049,18 +2153,15 @@ static ssize_t tun_put_user_xdp(struct tun_struct *tun, { int vnet_hdr_sz = 0; size_t size = xdp_frame->len; - size_t ret; + ssize_t ret; if (tun->flags & IFF_VNET_HDR) { struct virtio_net_hdr gso = { 0 }; vnet_hdr_sz = READ_ONCE(tun->vnet_hdr_sz); - if (unlikely(iov_iter_count(iter) < vnet_hdr_sz)) - return -EINVAL; - if (unlikely(copy_to_iter(&gso, sizeof(gso), iter) != - sizeof(gso))) - return -EFAULT; - iov_iter_advance(iter, vnet_hdr_sz - sizeof(gso)); + ret = tun_vnet_hdr_put(vnet_hdr_sz, iter, &gso); + if (ret) + return ret; } ret = copy_to_iter(xdp_frame->data, size, iter) + vnet_hdr_sz; @@ -2083,6 +2184,7 @@ static ssize_t tun_put_user(struct tun_struct *tun, int vlan_offset = 0; int vlan_hlen = 0; int vnet_hdr_sz = 0; + int ret; if (skb_vlan_tag_present(skb)) vlan_hlen = VLAN_HLEN; @@ -2108,33 +2210,14 @@ static ssize_t tun_put_user(struct tun_struct *tun, if (vnet_hdr_sz) { struct virtio_net_hdr gso; - int flags = tun->flags; - - if (iov_iter_count(iter) < vnet_hdr_sz) - return -EINVAL; - - if (virtio_net_hdr_from_skb(skb, &gso, - tun_is_little_endian(flags), true, - vlan_hlen)) { - struct skb_shared_info *sinfo = skb_shinfo(skb); - - if (net_ratelimit()) { - netdev_err(tun->dev, "unexpected GSO type: 0x%x, gso_size %d, hdr_len %d\n", - sinfo->gso_type, tun16_to_cpu(flags, gso.gso_size), - tun16_to_cpu(flags, gso.hdr_len)); - print_hex_dump(KERN_ERR, "tun: ", - DUMP_PREFIX_NONE, - 16, 1, skb->head, - min((int)tun16_to_cpu(flags, gso.hdr_len), 64), true); - } - WARN_ON_ONCE(1); - return -EINVAL; - } - if (copy_to_iter(&gso, sizeof(gso), iter) != sizeof(gso)) - return -EFAULT; + ret = tun_vnet_hdr_from_skb(tun->flags, tun->dev, skb, &gso); + if (ret) + return ret; - iov_iter_advance(iter, vnet_hdr_sz - sizeof(gso)); + ret = tun_vnet_hdr_put(vnet_hdr_sz, iter, &gso); + if (ret) + return ret; } if (vlan_hlen) { @@ -2494,7 +2577,7 @@ static int tun_xdp_one(struct tun_struct *tun, skb_reserve(skb, xdp->data - xdp->data_hard_start); skb_put(skb, xdp->data_end - xdp->data); - if (virtio_net_hdr_to_skb(skb, gso, tun_is_little_endian(tun->flags))) { + if (tun_vnet_hdr_to_skb(tun->flags, skb, gso)) { atomic_long_inc(&tun->rx_frame_errors); kfree_skb(skb); ret = -EINVAL; @@ -3078,8 +3161,6 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, kgid_t group; int ifindex; int sndbuf; - int vnet_hdr_sz; - int le; int ret; bool do_notify = false; @@ -3286,50 +3367,6 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, tun_set_sndbuf(tun); break; - case TUNGETVNETHDRSZ: - vnet_hdr_sz = tun->vnet_hdr_sz; - if (copy_to_user(argp, &vnet_hdr_sz, sizeof(vnet_hdr_sz))) - ret = -EFAULT; - break; - - case TUNSETVNETHDRSZ: - if (copy_from_user(&vnet_hdr_sz, argp, sizeof(vnet_hdr_sz))) { - ret = -EFAULT; - break; - } - if (vnet_hdr_sz < (int)sizeof(struct virtio_net_hdr)) { - ret = -EINVAL; - break; - } - - tun->vnet_hdr_sz = vnet_hdr_sz; - break; - - case TUNGETVNETLE: - le = !!(tun->flags & TUN_VNET_LE); - if (put_user(le, (int __user *)argp)) - ret = -EFAULT; - break; - - case TUNSETVNETLE: - if (get_user(le, (int __user *)argp)) { - ret = -EFAULT; - break; - } - if (le) - tun->flags |= TUN_VNET_LE; - else - tun->flags &= ~TUN_VNET_LE; - break; - - case TUNGETVNETBE: - ret = tun_get_vnet_be(tun->flags, argp); - break; - - case TUNSETVNETBE: - ret = tun_set_vnet_be(&tun->flags, argp); - break; - case TUNATTACHFILTER: /* Can be set only for TAPs */ ret = -EINVAL; @@ -3385,7 +3422,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; default: - ret = -EINVAL; + ret = tun_vnet_ioctl(&tun->vnet_hdr_sz, &tun->flags, cmd, argp); break; }