libceph: verify state after retaking con lock after dispatch
(cherry picked from commit 7b862e07b1a4d5c963d19027f10ea78085f27f9b)
We drop the con mutex when delivering a message. When we retake the
lock, we need to verify we are still in the OPEN state before
preparing to read the next tag, or else we risk stepping on a
connection that has been closed.
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 8edc0c1..bb21e5b 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -2003,7 +2003,6 @@
con->ops->dispatch(con, msg);
mutex_lock(&con->mutex);
- prepare_read_tag(con);
}
@@ -2213,6 +2212,8 @@
if (con->in_tag == CEPH_MSGR_TAG_READY)
goto more;
process_message(con);
+ if (con->state == CON_STATE_OPEN)
+ prepare_read_tag(con);
goto more;
}
if (con->in_tag == CEPH_MSGR_TAG_ACK) {