Commit 691412b4 authored Jan 04, 2016 by Kinglong Mee Committed by J. Bruce Fields Jan 07, 2016

nfsd: Fix nfsd leaks sunrpc module references



Stefan Hajnoczi reports,
nfsd leaks 3 references to the sunrpc module here:

  # echo -n "asdf 1234" >/proc/fs/nfsd/portlist
  bash: echo: write error: Protocol not supported

Now stop nfsd and try unloading the kernel modules:

  # systemctl stop nfs-server
  # systemctl stop nfs
  # systemctl stop proc-fs-nfsd.mount
  # systemctl stop var-lib-nfs-rpc_pipefs.mount
  # rmmod nfsd
  # rmmod nfs_acl
  # rmmod lockd
  # rmmod auth_rpcgss
  # rmmod sunrpc
  rmmod: ERROR: Module sunrpc is in use
  # lsmod | grep rpc
  sunrpc                315392  3

It is caused by nfsd don't cleanup rpcb program for nfsd
when destroying svc service after creating xprt fail.

Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

parent 2a297450

fs/nfsd/nfssvc.c

+3 −4

Original line number	Diff line number	Diff line
		@@ -378,14 +378,13 @@ static void nfsd_last_thread(struct svc_serv serv, struct net net)
		* write_ports can create the server without actually starting
		* any threads--if we get shut down before any threads are
		* started, then nfsd_last_thread will be run before any of this
		* other initialization has been done.
		* other initialization has been done except the rpcb information.
		*/
		svc_rpcb_cleanup(serv, net);
		if (!nn->nfsd_net_up)
		return;
		nfsd_shutdown_net(net);

		svc_rpcb_cleanup(serv, net);

		nfsd_shutdown_net(net);
		printk(KERN_WARNING "nfsd: last server has exited, flushing export "
		"cache\n");
		nfsd_export_flush(net);

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