From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ursula Braun Subject: [patch 11/13] [PATCH] af_iucv: cleanup and refactor recvmsg() EFAULT handling Date: Tue, 21 Apr 2009 12:35:08 +0200 Message-ID: <20090421103706.522654000@linux.vnet.ibm.com> References: <20090421103457.965299000@linux.vnet.ibm.com> Cc: schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, Hendrik Brueckner , Ursula Braun To: davem@davemloft.net, netdev@vger.kernel.org, linux-s390@vger.kernel.org Return-path: Received: from mtagate4.de.ibm.com ([195.212.29.153]:42851 "EHLO mtagate4.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754020AbZDUKhI (ORCPT ); Tue, 21 Apr 2009 06:37:08 -0400 Content-Disposition: inline; filename=611-af_iucv-recvmsg.diff Sender: netdev-owner@vger.kernel.org List-ID: From: Hendrik Brueckner If the skb cannot be copied to user iovec, always return -EFAULT. The skb is enqueued again, except MSG_PEEK flag is set, to allow user space applications to correct its iovec pointer. Signed-off-by: Hendrik Brueckner Signed-off-by: Ursula Braun --- net/iucv/af_iucv.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) Index: net-2.6-uschi/net/iucv/af_iucv.c =================================================================== --- net-2.6-uschi.orig/net/iucv/af_iucv.c +++ net-2.6-uschi/net/iucv/af_iucv.c @@ -968,7 +968,6 @@ static int iucv_sock_recvmsg(struct kioc int noblock = flags & MSG_DONTWAIT; struct sock *sk = sock->sk; struct iucv_sock *iucv = iucv_sk(sk); - int target; unsigned int copied, rlen; struct sk_buff *skb, *rskb, *cskb; int err = 0; @@ -982,8 +981,6 @@ static int iucv_sock_recvmsg(struct kioc if (flags & (MSG_OOB)) return -EOPNOTSUPP; - 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); @@ -998,10 +995,9 @@ static int iucv_sock_recvmsg(struct kioc cskb = skb; if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) { - skb_queue_head(&sk->sk_receive_queue, skb); - if (copied == 0) - return -EFAULT; - goto done; + if (!(flags & MSG_PEEK)) + skb_queue_head(&sk->sk_receive_queue, skb); + return -EFAULT; } /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */