Revert "udp: remove redundant variable"

This reverts commit 81d54ec847.

If we take the "try_again" goto, due to a checksum error,
the 'len' has already been truncated.  So we won't compute
the same values as the original code did.

Reported-by: paul bilke <fsmail@conspiracy.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2011-12-01 14:12:55 -05:00
parent b03b6dd58c
commit 59c2cdae27
2 changed files with 16 additions and 14 deletions

View File

@ -1164,7 +1164,7 @@ int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
struct inet_sock *inet = inet_sk(sk);
struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
struct sk_buff *skb;
unsigned int ulen;
unsigned int ulen, copied;
int peeked;
int err;
int is_udplite = IS_UDPLITE(sk);
@ -1186,9 +1186,10 @@ try_again:
goto out;
ulen = skb->len - sizeof(struct udphdr);
if (len > ulen)
len = ulen;
else if (len < ulen)
copied = len;
if (copied > ulen)
copied = ulen;
else if (copied < ulen)
msg->msg_flags |= MSG_TRUNC;
/*
@ -1197,14 +1198,14 @@ try_again:
* coverage checksum (UDP-Lite), do it before the copy.
*/
if (len < ulen || UDP_SKB_CB(skb)->partial_cov) {
if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
if (udp_lib_checksum_complete(skb))
goto csum_copy_err;
}
if (skb_csum_unnecessary(skb))
err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
msg->msg_iov, len);
msg->msg_iov, copied);
else {
err = skb_copy_and_csum_datagram_iovec(skb,
sizeof(struct udphdr),
@ -1233,7 +1234,7 @@ try_again:
if (inet->cmsg_flags)
ip_cmsg_recv(msg, skb);
err = len;
err = copied;
if (flags & MSG_TRUNC)
err = ulen;

View File

@ -340,7 +340,7 @@ int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
struct ipv6_pinfo *np = inet6_sk(sk);
struct inet_sock *inet = inet_sk(sk);
struct sk_buff *skb;
unsigned int ulen;
unsigned int ulen, copied;
int peeked;
int err;
int is_udplite = IS_UDPLITE(sk);
@ -363,9 +363,10 @@ try_again:
goto out;
ulen = skb->len - sizeof(struct udphdr);
if (len > ulen)
len = ulen;
else if (len < ulen)
copied = len;
if (copied > ulen)
copied = ulen;
else if (copied < ulen)
msg->msg_flags |= MSG_TRUNC;
is_udp4 = (skb->protocol == htons(ETH_P_IP));
@ -376,14 +377,14 @@ try_again:
* coverage checksum (UDP-Lite), do it before the copy.
*/
if (len < ulen || UDP_SKB_CB(skb)->partial_cov) {
if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
if (udp_lib_checksum_complete(skb))
goto csum_copy_err;
}
if (skb_csum_unnecessary(skb))
err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
msg->msg_iov,len);
msg->msg_iov, copied );
else {
err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
if (err == -EINVAL)
@ -432,7 +433,7 @@ try_again:
datagram_recv_ctl(sk, msg, skb);
}
err = len;
err = copied;
if (flags & MSG_TRUNC)
err = ulen;