diff options
Diffstat (limited to 'drivers/net/macvtap.c')
-rw-r--r-- | drivers/net/macvtap.c | 100 |
1 files changed, 78 insertions, 22 deletions
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 0427c6561c8..2ee56de7b0c 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -1,5 +1,6 @@ #include <linux/etherdevice.h> #include <linux/if_macvlan.h> +#include <linux/if_vlan.h> #include <linux/interrupt.h> #include <linux/nsproxy.h> #include <linux/compat.h> @@ -505,10 +506,11 @@ static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, if (copy > size) { ++from; --count; - } + offset = 0; + } else + offset += size; copy -= size; offset1 += size; - offset = 0; } if (len == offset1) @@ -518,24 +520,29 @@ static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, struct page *page[MAX_SKB_FRAGS]; int num_pages; unsigned long base; + unsigned long truesize; - len = from->iov_len - offset1; + len = from->iov_len - offset; if (!len) { - offset1 = 0; + offset = 0; ++from; continue; } - base = (unsigned long)from->iov_base + offset1; + base = (unsigned long)from->iov_base + offset; size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT; + if (i + size > MAX_SKB_FRAGS) + return -EMSGSIZE; num_pages = get_user_pages_fast(base, size, 0, &page[i]); - if ((num_pages != size) || - (num_pages > MAX_SKB_FRAGS - skb_shinfo(skb)->nr_frags)) - /* put_page is in skb free */ + if (num_pages != size) { + for (i = 0; i < num_pages; i++) + put_page(page[i]); return -EFAULT; + } + truesize = size * PAGE_SIZE; skb->data_len += len; skb->len += len; - skb->truesize += len; - atomic_add(len, &skb->sk->sk_wmem_alloc); + skb->truesize += truesize; + atomic_add(truesize, &skb->sk->sk_wmem_alloc); while (len) { int off = base & ~PAGE_MASK; int size = min_t(int, len, PAGE_SIZE - off); @@ -546,7 +553,7 @@ static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, len -= size; i++; } - offset1 = 0; + offset = 0; ++from; } return 0; @@ -646,7 +653,7 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, int err; struct virtio_net_hdr vnet_hdr = { 0 }; int vnet_hdr_len = 0; - int copylen; + int copylen = 0; bool zerocopy = false; if (q->flags & IFF_VNET_HDR) { @@ -675,15 +682,31 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, if (unlikely(len < ETH_HLEN)) goto err; + err = -EMSGSIZE; + if (unlikely(count > UIO_MAXIOV)) + goto err; + if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) zerocopy = true; if (zerocopy) { + /* Userspace may produce vectors with count greater than + * MAX_SKB_FRAGS, so we need to linearize parts of the skb + * to let the rest of data to be fit in the frags. + */ + if (count > MAX_SKB_FRAGS) { + copylen = iov_length(iv, count - MAX_SKB_FRAGS); + if (copylen < vnet_hdr_len) + copylen = 0; + else + copylen -= vnet_hdr_len; + } /* There are 256 bytes to be copied in skb, so there is enough * room for skb expand head in case it is used. * The rest buffer is mapped from userspace. */ - copylen = vnet_hdr.hdr_len; + if (copylen < vnet_hdr.hdr_len) + copylen = vnet_hdr.hdr_len; if (!copylen) copylen = GOODCOPY_LEN; } else @@ -694,10 +717,9 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, if (!skb) goto err; - if (zerocopy) { + if (zerocopy) err = zerocopy_sg_from_iovec(skb, iv, vnet_hdr_len, count); - skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; - } else + else err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len, len); if (err) @@ -716,8 +738,10 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, rcu_read_lock_bh(); vlan = rcu_dereference_bh(q->vlan); /* copy skb_ubuf_info for callback when skb has no error */ - if (zerocopy) + if (zerocopy) { skb_shinfo(skb)->destructor_arg = m->msg_control; + skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; + } if (vlan) macvlan_start_xmit(skb, vlan->dev); else @@ -759,6 +783,8 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q, struct macvlan_dev *vlan; int ret; int vnet_hdr_len = 0; + int vlan_offset = 0; + int copied; if (q->flags & IFF_VNET_HDR) { struct virtio_net_hdr vnet_hdr; @@ -773,18 +799,48 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q, if (memcpy_toiovecend(iv, (void *)&vnet_hdr, 0, sizeof(vnet_hdr))) return -EFAULT; } + copied = vnet_hdr_len; + + if (!vlan_tx_tag_present(skb)) + len = min_t(int, skb->len, len); + else { + int copy; + struct { + __be16 h_vlan_proto; + __be16 h_vlan_TCI; + } veth; + veth.h_vlan_proto = htons(ETH_P_8021Q); + veth.h_vlan_TCI = htons(vlan_tx_tag_get(skb)); + + vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); + len = min_t(int, skb->len + VLAN_HLEN, len); + + copy = min_t(int, vlan_offset, len); + ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy); + len -= copy; + copied += copy; + if (ret || !len) + goto done; + + copy = min_t(int, sizeof(veth), len); + ret = memcpy_toiovecend(iv, (void *)&veth, copied, copy); + len -= copy; + copied += copy; + if (ret || !len) + goto done; + } - len = min_t(int, skb->len, len); - - ret = skb_copy_datagram_const_iovec(skb, 0, iv, vnet_hdr_len, len); + ret = skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len); + copied += len; +done: rcu_read_lock_bh(); vlan = rcu_dereference_bh(q->vlan); if (vlan) - macvlan_count_rx(vlan, len, ret == 0, 0); + macvlan_count_rx(vlan, copied - vnet_hdr_len, ret == 0, 0); rcu_read_unlock_bh(); - return ret ? ret : (len + vnet_hdr_len); + return ret ? ret : copied; } static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb, |