diff options
| author | Ka-Cheong Poon <ka-cheong.poon@oracle.com> | 2018-04-11 00:57:25 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-20 08:21:07 +0200 |
| commit | fc89a75c246bbf7fc26b25ae29ee488abb6400c4 (patch) | |
| tree | 8734333702391d7a7823cbc3cdedcdada2c44134 | |
| parent | 6b61154b0680ebd3d82fd9415e9cd2c977bebcf2 (diff) | |
rds: MP-RDS may use an invalid c_path
[ Upstream commit a43cced9a348901f9015f4730b70b69e7c41a9c9 ]
rds_sendmsg() calls rds_send_mprds_hash() to find a c_path to use to
send a message. Suppose the RDS connection is not yet up. In
rds_send_mprds_hash(), it does
if (conn->c_npaths == 0)
wait_event_interruptible(conn->c_hs_waitq,
(conn->c_npaths != 0));
If it is interrupted before the connection is set up,
rds_send_mprds_hash() will return a non-zero hash value. Hence
rds_sendmsg() will use a non-zero c_path to send the message. But if
the RDS connection ends up to be non-MP capable, the message will be
lost as only the zero c_path can be used.
Signed-off-by: Ka-Cheong Poon <ka-cheong.poon@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/rds/send.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/net/rds/send.c b/net/rds/send.c index ef53d164e146..50241d30e16d 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2006 Oracle. All rights reserved. + * Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU @@ -983,10 +983,15 @@ static int rds_send_mprds_hash(struct rds_sock *rs, struct rds_connection *conn) if (conn->c_npaths == 0 && hash != 0) { rds_send_ping(conn); - if (conn->c_npaths == 0) { - wait_event_interruptible(conn->c_hs_waitq, - (conn->c_npaths != 0)); - } + /* The underlying connection is not up yet. Need to wait + * until it is up to be sure that the non-zero c_path can be + * used. But if we are interrupted, we have to use the zero + * c_path in case the connection ends up being non-MP capable. + */ + if (conn->c_npaths == 0) + if (wait_event_interruptible(conn->c_hs_waitq, + conn->c_npaths != 0)) + hash = 0; if (conn->c_npaths == 1) hash = 0; } |