From c21acd6731680a9af0bddd78f0920bda3af616bb Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Fri, 15 Dec 2023 11:56:31 +1100 Subject: [PATCH] nfsd: call nfsd_last_thread() before final nfsd_put() commit 2a501f55cd641eb4d3c16a2eab0d678693fac663 upstream. 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: ec52361df99b ("SUNRPC: stop using ->sv_nrthreads as a refcount") Signed-off-by: NeilBrown Reviewed-by: Jeff Layton Cc: Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfsctl.c | 9 +++++++-- fs/nfsd/nfsd.h | 1 + fs/nfsd/nfssvc.c | 2 +- 3 files changed, 9 insertions(+), 3 deletions(-) diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index 7ed02fb..98854dd 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -704,8 +704,10 @@ 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 && - !nn->nfsd_serv->sv_nrthreads && !xchg(&nn->keep_active, 1)) + 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); nfsd_put(net); @@ -756,6 +758,9 @@ out_close: svc_xprt_put(xprt); } out_err: + if (!nn->nfsd_serv->sv_nrthreads && !nn->keep_active) + nfsd_last_thread(net); + nfsd_put(net); return err; } diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index 11c14fa..63deed2 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -138,6 +138,7 @@ 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; diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 2114582..7ef6af9 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -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; -- 2.7.4