From 57c8b13e3cd0f94944c9691ce7f58e5fcef8a12d Mon Sep 17 00:00:00 2001 From: Stanislav Kinsbursky Date: Tue, 3 Jul 2012 16:46:41 +0400 Subject: [PATCH] NFSd: set nfsd_serv to NULL after service destruction In nfsd_destroy(): if (destroy) svc_shutdown_net(nfsd_serv, net); svc_destroy(nfsd_server); svc_shutdown_net(nfsd_serv, net) calls nfsd_last_thread(), which sets nfsd_serv to NULL, causing a NULL dereference on the following line. Signed-off-by: Stanislav Kinsbursky Signed-off-by: J. Bruce Fields --- fs/nfsd/nfsd.h | 2 ++ fs/nfsd/nfssvc.c | 10 +++++----- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index 7b248a24d5c5..2244222368ab 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -82,6 +82,8 @@ static inline void nfsd_destroy(struct net *net) if (destroy) svc_shutdown_net(nfsd_serv, net); svc_destroy(nfsd_serv); + if (destroy) + nfsd_serv = NULL; } #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 8621e36ce8dd..240473cb708f 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -254,8 +254,6 @@ static void nfsd_shutdown(void) static void nfsd_last_thread(struct svc_serv *serv, struct net *net) { - /* When last nfsd thread exits we need to do some clean-up */ - nfsd_serv = NULL; nfsd_shutdown(); svc_rpcb_cleanup(serv, net); @@ -332,6 +330,7 @@ static int nfsd_get_default_max_blksize(void) int nfsd_create_serv(void) { int error; + struct net *net = current->nsproxy->net_ns; WARN_ON(!mutex_is_locked(&nfsd_mutex)); if (nfsd_serv) { @@ -346,7 +345,7 @@ int nfsd_create_serv(void) if (nfsd_serv == NULL) return -ENOMEM; - error = svc_bind(nfsd_serv, current->nsproxy->net_ns); + error = svc_bind(nfsd_serv, net); if (error < 0) { svc_destroy(nfsd_serv); return error; @@ -557,12 +556,13 @@ nfsd(void *vrqstp) nfsdstats.th_cnt --; out: - if (rqstp->rq_server->sv_nrthreads == 1) - svc_shutdown_net(rqstp->rq_server, &init_net); + rqstp->rq_server = NULL; /* Release the thread */ svc_exit_thread(rqstp); + nfsd_destroy(&init_net); + /* Release module */ mutex_unlock(&nfsd_mutex); module_put_and_exit(0); -- 2.20.1