Commit 2a501f55 authored by NeilBrown's avatar NeilBrown Committed by Chuck Lever
Browse files

nfsd: call nfsd_last_thread() before final nfsd_put() 



If write_ports_addfd or write_ports_addxprt fail, they call nfsd_put()
without calling nfsd_last_thread().  This leaves nn->nfsd_serv pointing
to a structure that has been freed.

So remove 'static' from nfsd_last_thread() and call it when the
nfsd_serv is about to be destroyed.

Fixes: ec52361d ("SUNRPC: stop using ->sv_nrthreads as a refcount")
Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent bf51c52a

fs/nfsd/nfsctl.c

+7 −2
Original line number Diff line number Diff line
@@ -705,7 +705,9 @@ static ssize_t __write_ports_addfd(char *buf, struct net *net, const struct cred 


	err = svc_addsock(nn->nfsd_serv, net, fd, buf, SIMPLE_TRANSACTION_LIMIT, cred);



	if (err >= 0 &&

	if (err < 0 && !nn->nfsd_serv->sv_nrthreads && !nn->keep_active)

		nfsd_last_thread(net);

	else if (err >= 0 &&

		 !nn->nfsd_serv->sv_nrthreads && !xchg(&nn->keep_active, 1))

		svc_get(nn->nfsd_serv);
@@ -757,6 +759,9 @@ static ssize_t __write_ports_addxprt(char *buf, struct net *net, const struct cr 
		svc_xprt_put(xprt);

	}

out_err:

	if (!nn->nfsd_serv->sv_nrthreads && !nn->keep_active)

		nfsd_last_thread(net);



	nfsd_put(net);

	return err;

}

fs/nfsd/nfsd.h

+1 −0
Original line number Diff line number Diff line
@@ -155,6 +155,7 @@ int nfsd_vers(struct nfsd_net *nn, int vers, enum vers_op change); 
int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change);

void nfsd_reset_versions(struct nfsd_net *nn);

int nfsd_create_serv(struct net *net);

void nfsd_last_thread(struct net *net);



extern int nfsd_max_blksize;

fs/nfsd/nfssvc.c

+1 −1
Original line number Diff line number Diff line
@@ -542,7 +542,7 @@ static struct notifier_block nfsd_inet6addr_notifier = { 
/* Only used under nfsd_mutex, so this atomic may be overkill: */

static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);



static void nfsd_last_thread(struct net *net)

void nfsd_last_thread(struct net *net)

{

	struct nfsd_net *nn = net_generic(net, nfsd_net_id);

	struct svc_serv *serv = nn->nfsd_serv;