From 102a0743326a03cd1a1202ceda21e175b7d3575c Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:20:52 +0000
Subject: [PATCH] add new system file
---
kernel/drivers/net/tap.c | 141 +++++++++++++++++++++++++++++++++-------------
1 files changed, 100 insertions(+), 41 deletions(-)
diff --git a/kernel/drivers/net/tap.c b/kernel/drivers/net/tap.c
index f0f7cd9..41ee560 100644
--- a/kernel/drivers/net/tap.c
+++ b/kernel/drivers/net/tap.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
#include <linux/etherdevice.h>
#include <linux/if_tap.h>
#include <linux/if_vlan.h>
@@ -340,6 +341,7 @@
features |= tap->tap_features;
if (netif_needs_gso(skb, features)) {
struct sk_buff *segs = __skb_gso_segment(skb, features, false);
+ struct sk_buff *next;
if (IS_ERR(segs))
goto drop;
@@ -351,16 +353,13 @@
}
consume_skb(skb);
- while (segs) {
- struct sk_buff *nskb = segs->next;
-
- segs->next = NULL;
- if (ptr_ring_produce(&q->ring, segs)) {
- kfree_skb(segs);
- kfree_skb_list(nskb);
+ skb_list_walk_safe(segs, skb, next) {
+ skb_mark_not_on_list(skb);
+ if (ptr_ring_produce(&q->ring, skb)) {
+ kfree_skb(skb);
+ kfree_skb_list(next);
break;
}
- segs = nskb;
}
} else {
/* If we receive a partial checksum and the tap side
@@ -519,13 +518,12 @@
goto err;
}
- RCU_INIT_POINTER(q->sock.wq, &q->wq);
- init_waitqueue_head(&q->wq.wait);
+ init_waitqueue_head(&q->sock.wq.wait);
q->sock.type = SOCK_RAW;
q->sock.state = SS_CONNECTED;
q->sock.file = file;
q->sock.ops = &tap_socket_ops;
- sock_init_data(&q->sock, &q->sk);
+ sock_init_data_uid(&q->sock, &q->sk, current_fsuid());
q->sk.sk_write_space = tap_sock_write_space;
q->sk.sk_destruct = tap_sock_destruct;
q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP;
@@ -578,7 +576,7 @@
goto out;
mask = 0;
- poll_wait(file, &q->wq.wait, wait);
+ poll_wait(file, &q->sock.wq.wait, wait);
if (!ptr_ring_empty(&q->ring))
mask |= EPOLLIN | EPOLLRDNORM;
@@ -619,7 +617,7 @@
#define TAP_RESERVE HH_DATA_OFF(ETH_HLEN)
/* Get packet from user space buffer */
-static ssize_t tap_get_user(struct tap_queue *q, struct msghdr *m,
+static ssize_t tap_get_user(struct tap_queue *q, void *msg_control,
struct iov_iter *from, int noblock)
{
int good_linear = SKB_MAX_HEAD(TAP_RESERVE);
@@ -663,7 +661,7 @@
if (unlikely(len < ETH_HLEN))
goto err;
- if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) {
+ if (msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) {
struct iov_iter i;
copylen = vnet_hdr.hdr_len ?
@@ -712,23 +710,22 @@
goto err_kfree;
}
- skb_probe_transport_header(skb, ETH_HLEN);
+ skb_probe_transport_header(skb);
/* Move network header to the right position for VLAN tagged packets */
- if ((skb->protocol == htons(ETH_P_8021Q) ||
- skb->protocol == htons(ETH_P_8021AD)) &&
- __vlan_get_protocol(skb, skb->protocol, &depth) != 0)
+ if (eth_type_vlan(skb->protocol) &&
+ vlan_get_protocol_and_depth(skb, skb->protocol, &depth) != 0)
skb_set_network_header(skb, depth);
rcu_read_lock();
tap = rcu_dereference(q->tap);
/* copy skb_ubuf_info for callback when skb has no error */
if (zerocopy) {
- skb_shinfo(skb)->destructor_arg = m->msg_control;
+ skb_shinfo(skb)->destructor_arg = msg_control;
skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
- } else if (m && m->msg_control) {
- struct ubuf_info *uarg = m->msg_control;
+ } else if (msg_control) {
+ struct ubuf_info *uarg = msg_control;
uarg->callback(uarg, false);
}
@@ -830,8 +827,7 @@
ssize_t ret = 0;
if (!iov_iter_count(to)) {
- if (skb)
- kfree_skb(skb);
+ kfree_skb(skb);
return 0;
}
@@ -1096,10 +1092,9 @@
return -ENOLINK;
}
ret = 0;
- u = tap->dev->type;
+ dev_get_mac_address(&sa, dev_net(tap->dev), tap->dev->name);
if (copy_to_user(&ifr->ifr_name, tap->dev->name, IFNAMSIZ) ||
- copy_to_user(&ifr->ifr_hwaddr.sa_data, tap->dev->dev_addr, ETH_ALEN) ||
- put_user(u, &ifr->ifr_hwaddr.sa_family))
+ copy_to_user(&ifr->ifr_hwaddr, &sa, sizeof(sa)))
ret = -EFAULT;
tap_put_tap_dev(tap);
rtnl_unlock();
@@ -1114,7 +1109,7 @@
rtnl_unlock();
return -ENOLINK;
}
- ret = dev_set_mac_address(tap->dev, &sa);
+ ret = dev_set_mac_address_user(tap->dev, &sa, NULL);
tap_put_tap_dev(tap);
rtnl_unlock();
return ret;
@@ -1123,14 +1118,6 @@
return -EINVAL;
}
}
-
-#ifdef CONFIG_COMPAT
-static long tap_compat_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- return tap_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
-}
-#endif
static const struct file_operations tap_fops = {
.owner = THIS_MODULE,
@@ -1141,16 +1128,89 @@
.poll = tap_poll,
.llseek = no_llseek,
.unlocked_ioctl = tap_ioctl,
-#ifdef CONFIG_COMPAT
- .compat_ioctl = tap_compat_ioctl,
-#endif
+ .compat_ioctl = compat_ptr_ioctl,
};
+
+static int tap_get_user_xdp(struct tap_queue *q, struct xdp_buff *xdp)
+{
+ struct tun_xdp_hdr *hdr = xdp->data_hard_start;
+ struct virtio_net_hdr *gso = &hdr->gso;
+ int buflen = hdr->buflen;
+ int vnet_hdr_len = 0;
+ struct tap_dev *tap;
+ struct sk_buff *skb;
+ int err, depth;
+
+ if (q->flags & IFF_VNET_HDR)
+ vnet_hdr_len = READ_ONCE(q->vnet_hdr_sz);
+
+ skb = build_skb(xdp->data_hard_start, buflen);
+ if (!skb) {
+ err = -ENOMEM;
+ goto err;
+ }
+
+ skb_reserve(skb, xdp->data - xdp->data_hard_start);
+ skb_put(skb, xdp->data_end - xdp->data);
+
+ skb_set_network_header(skb, ETH_HLEN);
+ skb_reset_mac_header(skb);
+ skb->protocol = eth_hdr(skb)->h_proto;
+
+ if (vnet_hdr_len) {
+ err = virtio_net_hdr_to_skb(skb, gso, tap_is_little_endian(q));
+ if (err)
+ goto err_kfree;
+ }
+
+ /* Move network header to the right position for VLAN tagged packets */
+ if (eth_type_vlan(skb->protocol) &&
+ vlan_get_protocol_and_depth(skb, skb->protocol, &depth) != 0)
+ skb_set_network_header(skb, depth);
+
+ rcu_read_lock();
+ tap = rcu_dereference(q->tap);
+ if (tap) {
+ skb->dev = tap->dev;
+ skb_probe_transport_header(skb);
+ dev_queue_xmit(skb);
+ } else {
+ kfree_skb(skb);
+ }
+ rcu_read_unlock();
+
+ return 0;
+
+err_kfree:
+ kfree_skb(skb);
+err:
+ rcu_read_lock();
+ tap = rcu_dereference(q->tap);
+ if (tap && tap->count_tx_dropped)
+ tap->count_tx_dropped(tap);
+ rcu_read_unlock();
+ return err;
+}
static int tap_sendmsg(struct socket *sock, struct msghdr *m,
size_t total_len)
{
struct tap_queue *q = container_of(sock, struct tap_queue, sock);
- return tap_get_user(q, m, &m->msg_iter, m->msg_flags & MSG_DONTWAIT);
+ struct tun_msg_ctl *ctl = m->msg_control;
+ struct xdp_buff *xdp;
+ int i;
+
+ if (m->msg_controllen == sizeof(struct tun_msg_ctl) &&
+ ctl && ctl->type == TUN_MSG_PTR) {
+ for (i = 0; i < ctl->num; i++) {
+ xdp = &((struct xdp_buff *)ctl->ptr)[i];
+ tap_get_user_xdp(q, xdp);
+ }
+ return 0;
+ }
+
+ return tap_get_user(q, ctl ? ctl->ptr : NULL, &m->msg_iter,
+ m->msg_flags & MSG_DONTWAIT);
}
static int tap_recvmsg(struct socket *sock, struct msghdr *m,
@@ -1160,8 +1220,7 @@
struct sk_buff *skb = m->msg_control;
int ret;
if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) {
- if (skb)
- kfree_skb(skb);
+ kfree_skb(skb);
return -EINVAL;
}
ret = tap_do_read(q, &m->msg_iter, flags & MSG_DONTWAIT, skb);
--
Gitblit v1.6.2