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 <vyasev...@gmail.com>
Cc: Zhi Yong Wu <wu...@linux.vnet.ibm.com>
Cc: Michael S. Tsirkin <m...@redhat.com>
Signed-off-by: Jason Wang <jasow...@redhat.com>
---
Changes from v1:
- increase total unconditionally
- do not move the structure veth out of the vlan handling block
---
drivers/net/macvtap.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index 957cc5c..ded4b2c 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -770,7 +770,7 @@ 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, offset;
if (q->flags & IFF_VNET_HDR) {
struct virtio_net_hdr vnet_hdr;
@@ -785,7 +785,8 @@ 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;
+ offset = copied = vnet_hdr_len;
+ copied += skb->len;
if (!vlan_tx_tag_present(skb))
len = min_t(int, skb->len, len);
@@ -800,24 +801,24 @@ 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);
+ copied += VLAN_HLEN;
copy = min_t(int, vlan_offset, len);
- ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy);
+ ret = skb_copy_datagram_const_iovec(skb, 0, iv, offset, copy);
len -= copy;
- copied += copy;
+ offset += copy;
if (ret || !len)
goto done;
copy = min_t(int, sizeof(veth), len);
- ret = memcpy_toiovecend(iv, (void *)&veth, copied, copy);
+ ret = memcpy_toiovecend(iv, (void *)&veth, offset, copy);
len -= copy;
- copied += copy;
+ offset += copy;
if (ret || !len)
goto done;
}
- ret = skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len);
- copied += len;
+ ret = skb_copy_datagram_const_iovec(skb, vlan_offset, iv, offset, len);
done:
return ret ? ret : copied;
@@ -875,7 +876,7 @@ 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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
