From ee7f8e405342722e42c15fe8e841a679f8951eea Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Wed, 1 Feb 2006 21:07:01 -0600 Subject: [PATCH] [SCSI] iscsi update: set deamon pid earlier >From michaelc@cs.wisc.edu: If the transport lookup fails we set the daemon pid too late. This can cause us deadlock since the netlink code will think we meant to call back into our iscsi_if_rx function. Signed-off-by: Mike Christie Signed-off-by: Alex Aizman Signed-off-by: Dmitry Yusupov Signed-off-by: James Bottomley --- drivers/scsi/scsi_transport_iscsi.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index 448fd78777f9..7fb69183c72d 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -846,9 +846,6 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) struct iscsi_cls_session *session; struct iscsi_cls_conn *conn; - if (NETLINK_CREDS(skb)->uid) - return -EPERM; - priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle)); if (!priv) return -EINVAL; @@ -857,8 +854,6 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) if (!try_module_get(transport->owner)) return -EINVAL; - daemon_pid = NETLINK_CREDS(skb)->pid; - switch (nlh->nlmsg_type) { case ISCSI_UEVENT_CREATE_SESSION: err = iscsi_if_create_session(priv, ev); @@ -934,7 +929,7 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) /* Get message from skb (based on rtnetlink_rcv_skb). Each message is * processed by iscsi_if_recv_msg. Malformed skbs with wrong length are - * discarded silently. */ + * or invalid creds discarded silently. */ static void iscsi_if_rx(struct sock *sk, int len) { @@ -942,6 +937,12 @@ iscsi_if_rx(struct sock *sk, int len) mutex_lock(&rx_queue_mutex); while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) { + if (NETLINK_CREDS(skb)->uid) { + skb_pull(skb, skb->len); + goto free_skb; + } + daemon_pid = NETLINK_CREDS(skb)->pid; + while (skb->len >= NLMSG_SPACE(0)) { int err; uint32_t rlen; @@ -953,10 +954,12 @@ iscsi_if_rx(struct sock *sk, int len) skb->len < nlh->nlmsg_len) { break; } + ev = NLMSG_DATA(nlh); rlen = NLMSG_ALIGN(nlh->nlmsg_len); if (rlen > skb->len) rlen = skb->len; + err = iscsi_if_recv_msg(skb, nlh); if (err) { ev->type = ISCSI_KEVENT_IF_ERROR; @@ -980,6 +983,7 @@ iscsi_if_rx(struct sock *sk, int len) } while (err < 0 && err != -ECONNREFUSED); skb_pull(skb, rlen); } +free_skb: kfree_skb(skb); } mutex_unlock(&rx_queue_mutex); -- 2.30.2