From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
commit f00432063db1a0db484e85193eccc6845435b80e upstream.
We must ensure that all sockets are closed before we call xprt_free()
and release the reference to the net namespace. The problem is that
calling fput() will defer closing the socket until delayed_fput() gets
called.
Let's fix the situation by allowing rpciod and the transport teardown
code (which runs on the system wq) to call __fput_sync(), and directly
close the socket.
Reported-by: Felix Fu <foyjog@xxxxxxxxx>
Acked-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Fixes: a73881c96d73 ("SUNRPC: Fix an Oops in udp_poll()")
Cc: stable@xxxxxxxxxxxxxxx # 5.1.x: 3be232f11a3c: SUNRPC: Prevent immediate close+reconnect
Cc: stable@xxxxxxxxxxxxxxx # 5.1.x: 89f42494f92f: SUNRPC: Don't call connect() more than once on a TCP socket
Cc: stable@xxxxxxxxxxxxxxx # 5.1.x
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Meena Shanmugam <meenashanmugam@xxxxxxxxxx>
---
fs/file_table.c | 1 +
include/trace/events/sunrpc.h | 1 -
net/sunrpc/xprt.c | 7 +------
net/sunrpc/xprtsock.c | 16 +++++++++++++---
4 files changed, 15 insertions(+), 10 deletions(-)
diff --git a/fs/file_table.c b/fs/file_table.c
index fbd45a1a0e7e..12aaa04ac5b7 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -377,6 +377,7 @@ void __fput_sync(struct file *file)
}
EXPORT_SYMBOL(fput);
+EXPORT_SYMBOL(__fput_sync);
void __init files_init(void)
{
diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h
index ed1bbac004d5..8220369ee610 100644
--- a/include/trace/events/sunrpc.h
+++ b/include/trace/events/sunrpc.h
@@ -1006,7 +1006,6 @@ DEFINE_RPC_XPRT_LIFETIME_EVENT(connect);
DEFINE_RPC_XPRT_LIFETIME_EVENT(disconnect_auto);
DEFINE_RPC_XPRT_LIFETIME_EVENT(disconnect_done);
DEFINE_RPC_XPRT_LIFETIME_EVENT(disconnect_force);
-DEFINE_RPC_XPRT_LIFETIME_EVENT(disconnect_cleanup);
DEFINE_RPC_XPRT_LIFETIME_EVENT(destroy);
DECLARE_EVENT_CLASS(rpc_xprt_event,
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index af0159459c75..13d5323f8098 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -886,12 +886,7 @@ void xprt_connect(struct rpc_task *task)
if (!xprt_lock_write(xprt, task))
return;
- if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) {
- trace_xprt_disconnect_cleanup(xprt);
- xprt->ops->close(xprt);
- }
-
- if (!xprt_connected(xprt)) {
+ if (!xprt_connected(xprt) && !test_bit(XPRT_CLOSE_WAIT, &xprt->state)) {
task->tk_rqstp->rq_connect_cookie = xprt->connect_cookie;
rpc_sleep_on_timeout(&xprt->pending, task, NULL,
xprt_request_timeout(task->tk_rqstp));
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 33a81f9703b1..71c0ec9eaf0b 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -871,7 +871,7 @@ static int xs_local_send_request(struct rpc_rqst *req)
/* Close the stream if the previous transmission was incomplete */
if (xs_send_request_was_aborted(transport, req)) {
- xs_close(xprt);
+ xprt_force_disconnect(xprt);
return -ENOTCONN;
}
@@ -909,7 +909,7 @@ static int xs_local_send_request(struct rpc_rqst *req)
-status);
fallthrough;
case -EPIPE:
- xs_close(xprt);
+ xprt_force_disconnect(xprt);
status = -ENOTCONN;
}
@@ -1191,6 +1191,16 @@ static void xs_reset_transport(struct sock_xprt *transport)
if (sk == NULL)
return;
+ /*
+ * Make sure we're calling this in a context from which it is safe
+ * to call __fput_sync(). In practice that means rpciod and the
+ * system workqueue.
+ */
+ if (!(current->flags & PF_WQ_WORKER)) {
+ WARN_ON_ONCE(1);
+ set_bit(XPRT_CLOSE_WAIT, &xprt->state);
+ return;
+ }
if (atomic_read(&transport->xprt.swapper))
sk_clear_memalloc(sk);
@@ -1214,7 +1224,7 @@ static void xs_reset_transport(struct sock_xprt *transport)
mutex_unlock(&transport->recv_mutex);
trace_rpc_socket_close(xprt, sock);
- fput(filp);
+ __fput_sync(filp);
xprt_disconnect_done(xprt);
}
--
2.36.0.550.gb090851708-goog
