[ 157/187] Lockd: pass network namespace to creation and destruction routines

Greg Kroah-Hartman
2012-07-12T22:44:51Z

From: Stanislav Kinsbursky <skinsbursky@parallels.com>

upstream commit e3f70eadb7dddfb5a2bb9afff7abfc6ee17a29d0.

v2: dereference of most probably already released nlm_host removed in
nlmclnt_done() and reclaimer().

These routines are called from locks reclaimer() kernel thread. This thread
works in "init_net" network context and currently relays on persence on lockd
thread and it's per-net resources. Thus lockd_up() and lockd_down() can't relay
on current network context. So let's pass corrent one into them.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/lockd/clntlock.c | 13 ++++++++-----
fs/lockd/svc.c | 7 +++----
fs/nfsd/nfssvc.c | 6 +++---
include/linux/lockd/bind.h | 4 ++--
4 files changed, 16 insertions(+), 14 deletions(-)

--- a/fs/lockd/clntlock.c
+++ b/fs/lockd/clntlock.c
@@ -56,7 +56,7 @@ struct nlm_host *nlmclnt_init(const stru
u32 nlm_version = (nlm_init->nfs_version == 2) ? 1 : 4;
int status;

- status = lockd_up();
+ status = lockd_up(nlm_init->net);
if (status < 0)
return ERR_PTR(status);

@@ -65,7 +65,7 @@ struct nlm_host *nlmclnt_init(const stru
nlm_init->hostname, nlm_init->noresvport,
nlm_init->net);
if (host == NULL) {
- lockd_down();
+ lockd_down(nlm_init->net);
return ERR_PTR(-ENOLCK);
}

@@ -80,8 +80,10 @@ EXPORT_SYMBOL_GPL(nlmclnt_init);
*/
void nlmclnt_done(struct nlm_host *host)
{
+ struct net *net = host->net;
+
nlmclnt_release_host(host);
- lockd_down();
+ lockd_down(net);
}
EXPORT_SYMBOL_GPL(nlmclnt_done);

@@ -220,11 +222,12 @@ reclaimer(void *ptr)
struct nlm_wait *block;
struct file_lock *fl, *next;
u32 nsmstate;
+ struct net *net = host->net;

allow_signal(SIGKILL);

down_write(&host->h_rwsem);
- lockd_up(); /* note: this cannot fail as lockd is already running */
+ lockd_up(net); /* note: this cannot fail as lockd is already running */

dprintk("lockd: reclaiming locks for host %s\n", host->h_name);

@@ -275,6 +278,6 @@ restart:

/* Release host handle after use */
nlmclnt_release_host(host);
- lockd_down();
+ lockd_down(net);
return 0;
}
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -295,11 +295,10 @@ static void lockd_down_net(struct net *n
/*
* Bring up the lockd process if it's not already up.
*/
-int lockd_up(void)
+int lockd_up(struct net *net)
{
struct svc_serv *serv;
int error = 0;
- struct net *net = current->nsproxy->net_ns;

mutex_lock(&nlmsvc_mutex);
/*
@@ -378,12 +377,12 @@ EXPORT_SYMBOL_GPL(lockd_up);
* Decrement the user count and bring down lockd if we're the last.
*/
void
-lockd_down(void)
+lockd_down(struct net *net)
{
mutex_lock(&nlmsvc_mutex);
if (nlmsvc_users) {
if (--nlmsvc_users) {
- lockd_down_net(current->nsproxy->net_ns);
+ lockd_down_net(net);
goto out;
}
} else {
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -220,7 +220,7 @@ static int nfsd_startup(unsigned short p
ret = nfsd_init_socks(port);
if (ret)
goto out_racache;
- ret = lockd_up();
+ ret = lockd_up(&init_net);
if (ret)
goto out_racache;
ret = nfs4_state_start();
@@ -229,7 +229,7 @@ static int nfsd_startup(unsigned short p
nfsd_up = true;
return 0;
out_lockd:
- lockd_down();
+ lockd_down(&init_net);
out_racache:
nfsd_racache_shutdown();
return ret;
@@ -246,7 +246,7 @@ static void nfsd_shutdown(void)
if (!nfsd_up)
return;
nfs4_state_shutdown();
- lockd_down();
+ lockd_down(&init_net);
nfsd_racache_shutdown();
nfsd_up = false;
}
--- a/include/linux/lockd/bind.h
+++ b/include/linux/lockd/bind.h
@@ -54,7 +54,7 @@ extern void nlmclnt_done(struct nlm_host

extern int nlmclnt_proc(struct nlm_host *host, int cmd,
struct file_lock *fl);
-extern int lockd_up(void);
-extern void lockd_down(void);
+extern int lockd_up(struct net *net);
+extern void lockd_down(struct net *net);

#endif /* LINUX_LOCKD_BIND_H */