Commit 60d3705f authored Apr 21, 2009 by Hendrik Brueckner Committed by David S. Miller Apr 21, 2009

af_iucv: fix oops in iucv_sock_recvmsg() for MSG_PEEK flag

If iucv_sock_recvmsg() is called with MSG_PEEK flag set, the skb is enqueued
twice. If the socket is then closed, the pointer to the skb is freed twice.

Remove the skb_queue_head() call for MSG_PEEK, because the skb_recv_datagram()
function already handles MSG_PEEK (does not dequeue the skb).

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent bbe188c8

net/iucv/af_iucv.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -814,6 +814,8 @@ static int iucv_sock_recvmsg(struct kiocb iocb, struct socket sock,

		target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);

		/* receive/dequeue next skb:
		* the function understands MSG_PEEK and, thus, does not dequeue skb */
		skb = skb_recv_datagram(sk, flags, noblock, &err);
		if (!skb) {
		if (sk->sk_shutdown & RCV_SHUTDOWN)
		@@ -861,9 +863,7 @@ static int iucv_sock_recvmsg(struct kiocb iocb, struct socket sock,
		iucv_process_message_q(sk);
		spin_unlock_bh(&iucv->message_q.lock);
		}

		} else
		skb_queue_head(&sk->sk_receive_queue, skb);
		}

		done:
		return err ? : copied;

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