tun: fix tun_chr_aio_read so that aio works
aio_read gets const struct iovec * but tun_chr_aio_read casts this to struct
iovec * and modifies the iovec. As a result, attempts to use io_submit
to get packets from a tun device fail with weird errors such as EINVAL.
Fix by using the new skb_copy_datagram_const_iovec.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 735bf41..3b513e2 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -683,7 +683,7 @@
/* Put packet to the user space buffer */
static __inline__ ssize_t tun_put_user(struct tun_struct *tun,
struct sk_buff *skb,
- struct iovec *iv, int len)
+ const struct iovec *iv, int len)
{
struct tun_pi pi = { 0, skb->protocol };
ssize_t total = 0;
@@ -697,7 +697,7 @@
pi.flags |= TUN_PKT_STRIP;
}
- if (memcpy_toiovec(iv, (void *) &pi, sizeof(pi)))
+ if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi)))
return -EFAULT;
total += sizeof(pi);
}
@@ -730,14 +730,15 @@
gso.csum_offset = skb->csum_offset;
} /* else everything is zero */
- if (unlikely(memcpy_toiovec(iv, (void *)&gso, sizeof(gso))))
+ if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
+ sizeof(gso))))
return -EFAULT;
total += sizeof(gso);
}
len = min_t(int, skb->len, len);
- skb_copy_datagram_iovec(skb, 0, iv, len);
+ skb_copy_datagram_const_iovec(skb, 0, iv, total, len);
total += len;
tun->dev->stats.tx_packets++;
@@ -792,7 +793,7 @@
}
netif_wake_queue(tun->dev);
- ret = tun_put_user(tun, skb, (struct iovec *) iv, len);
+ ret = tun_put_user(tun, skb, iv, len);
kfree_skb(skb);
break;
}