Decouple the vnet handling code so that we can reuse it for tap.
Signed-off-by: Akihiko Odaki <akihiko.od...@daynix.com>
Reviewed-by: Willem de Bruijn <will...@google.com>
---
drivers/net/tun.c | 237 ++++++++++++++++++++++++++++++++----------------------
1 file changed, 139 insertions(+), 98 deletions(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index
8ddd4b352f0307e52cdff75254b5ac1d259d51f8..5bd1c21032ed673ba8e39dd5a488cce11599855b
100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -351,6 +351,127 @@ 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 *vnet_hdr_sz, unsigned int *flags,
+ unsigned int cmd, int __user *sp)
+{
+ int s;
+
+ switch (cmd) {
+ case TUNGETVNETHDRSZ:
+ s = *vnet_hdr_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;
+
+ *vnet_hdr_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)
+{
+ u16 hdr_len;
+
+ if (iov_iter_count(from) < sz)
+ return -EINVAL;
+
+ if (!copy_from_iter_full(hdr, sizeof(*hdr), from))
+ return -EFAULT;
+
+ hdr_len = tun16_to_cpu(flags, hdr->hdr_len);
+
+ if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
+ hdr_len = max(tun16_to_cpu(flags, hdr->csum_start) +
tun16_to_cpu(flags, hdr->csum_offset) + 2, hdr_len);
+ hdr->hdr_len = cpu_to_tun16(flags, hdr_len);
+ }
+
+ if (hdr_len > iov_iter_count(from))
+ return -EINVAL;
+
+ iov_iter_advance(from, sz - sizeof(*hdr));
+
+ return 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;
@@ -1764,25 +1885,12 @@ 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 (len < vnet_hdr_sz)
- return -EINVAL;
- len -= vnet_hdr_sz;
-
- if (!copy_from_iter_full(&gso, sizeof(gso), from))
- return -EFAULT;
-
- hdr_len = tun16_to_cpu(flags, gso.hdr_len);
- if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
- hdr_len = max(tun16_to_cpu(flags, gso.csum_start) +
tun16_to_cpu(flags, gso.csum_offset) + 2, hdr_len);
- gso.hdr_len = cpu_to_tun16(flags, hdr_len);
- }
+ hdr_len = tun_vnet_hdr_get(vnet_hdr_sz, tun->flags, from, &gso);
+ if (hdr_len < 0)
+ return hdr_len;
- if (hdr_len > len)
- return -EINVAL;
- iov_iter_advance(from, vnet_hdr_sz - sizeof(gso));
+ len -= vnet_hdr_sz;
}
if ((tun->flags & TUN_TYPE_MASK) == IFF_TAP) {
@@ -1856,7 +1964,7 @@ 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;
@@ -2051,18 +2159,15 @@ 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;
@@ -2085,6 +2190,7 @@ 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;
@@ -2110,33 +2216,14 @@ 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) {
@@ -2496,7 +2583,7 @@ 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;
@@ -3080,8 +3167,6 @@ 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;
@@ -3288,50 +3373,6 @@ 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;
@@ -3387,7 +3428,7 @@ 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;
}
--
2.48.1
