diff options
| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-05-23 19:24:36 +0200 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-05-23 21:21:13 +0200 |
| commit | 4697bd5e9419348ef9fa9b55cefe4355ad9d3d01 (patch) | |
| tree | 20bf5da80d10ec4df42ae0c3067af39a36f11c28 /fs/nfs/idmap.c | |
| parent | NFSv4.1: Fix session initialisation races (diff) | |
| download | linux-4697bd5e9419348ef9fa9b55cefe4355ad9d3d01.tar.xz linux-4697bd5e9419348ef9fa9b55cefe4355ad9d3d01.zip | |
NFSv4: Fix a race in the net namespace mount notification
Since the struct nfs_client gets added to the global nfs_client_list
before it is initialised, it is possible that rpc_pipefs_event can
end up trying to create idmapper entries on such a thing.
The solution is to have the mount notification wait for the
initialisation of each nfs_client to complete, and then to
skip any entries for which the it failed.
Reported-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Diffstat (limited to 'fs/nfs/idmap.c')
| -rw-r--r-- | fs/nfs/idmap.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c index 2eaecf9d8db7..861be75eb165 100644 --- a/fs/nfs/idmap.c +++ b/fs/nfs/idmap.c @@ -530,9 +530,24 @@ static struct nfs_client *nfs_get_client_for_event(struct net *net, int event) struct nfs_net *nn = net_generic(net, nfs_net_id); struct dentry *cl_dentry; struct nfs_client *clp; + int err; +restart: spin_lock(&nn->nfs_client_lock); list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) { + /* Wait for initialisation to finish */ + if (clp->cl_cons_state == NFS_CS_INITING) { + atomic_inc(&clp->cl_count); + spin_unlock(&nn->nfs_client_lock); + err = nfs_wait_client_init_complete(clp); + nfs_put_client(clp); + if (err) + return NULL; + goto restart; + } + /* Skip nfs_clients that failed to initialise */ + if (clp->cl_cons_state < 0) + continue; if (clp->rpc_ops != &nfs_v4_clientops) continue; cl_dentry = clp->cl_idmap->idmap_pipe->dentry; |