| From | Luis Henriques <> | Subject | [PATCH 3.5 79/96] macvtap: signal truncated packets | Date | Mon, 13 Jan 2014 14:24:42 +0000 |
| |
3.5.7.29 -stable review patch. If anyone has any objections, please let me know.
------------------
From: Jason Wang <jasowang@redhat.com>
commit ce232ce01d61b184202bb185103d119820e1260c upstream.
macvtap_put_user() never return a value grater than iov length, this in fact bypasses the truncated checking in macvtap_recvmsg(). Fix this by always returning the size of packet plus the possible vlan header to let the trunca checking work.
Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/net/macvtap.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index b614ab4..eec890e 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -801,7 +801,7 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q, int ret; int vnet_hdr_len = 0; int vlan_offset = 0; - int copied; + int copied, total; if (q->flags & IFF_VNET_HDR) { struct virtio_net_hdr vnet_hdr; @@ -816,7 +816,8 @@ 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; + total = copied = vnet_hdr_len; + total += skb->len; if (!vlan_tx_tag_present(skb)) len = min_t(int, skb->len, len); @@ -831,6 +832,7 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q, vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); len = min_t(int, skb->len + VLAN_HLEN, len); + total += VLAN_HLEN; copy = min_t(int, vlan_offset, len); ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy); @@ -848,10 +850,9 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q, } ret = skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len); - copied += len; done: - return ret ? ret : copied; + return ret ? ret : total; } static ssize_t macvtap_do_read(struct macvtap_queue *q, struct kiocb *iocb, @@ -905,7 +906,7 @@ static ssize_t macvtap_aio_read(struct kiocb *iocb, const struct iovec *iv, } ret = macvtap_do_read(q, iocb, iv, len, file->f_flags & O_NONBLOCK); - ret = min_t(ssize_t, ret, len); /* XXX copied from tun.c. Why? */ + ret = min_t(ssize_t, ret, len); if (ret > 0) iocb->ki_pos = ret; out: -- 1.8.3.2
|