diff options
| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2013-01-18 22:41:53 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-02-03 18:27:05 -0600 |
| commit | 607f8acb842d81ab83895d458dacbcbf62729d7d (patch) | |
| tree | 66f6b4eb1e0bf15b5c0ddba8c9a8c3cdd9082e5d /fs | |
| parent | 8900c903a85433be3b66fbbf0e15ff6bba0678b0 (diff) | |
NFSv4: Fix NFSv4 reference counting for trunked sessions
commit 4ae19c2dd713edb7b8ad3d4ab9d234ed5dcb6b98 upstream.
The reference counting in nfs4_init_client assumes wongly that it
is safe for nfs4_discover_server_trunking() to return a pointer to a
nfs_client prior to bumping the reference count.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Ben Greear <greearb@candelatech.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/nfs/nfs4client.c | 31 |
1 files changed, 15 insertions, 16 deletions
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index 6bacfde1319a..0cdabd6268be 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -235,11 +235,10 @@ struct nfs_client *nfs4_init_client(struct nfs_client *clp, error = nfs4_discover_server_trunking(clp, &old); if (error < 0) goto error; + nfs_put_client(clp); if (clp != old) { clp->cl_preserve_clid = true; - nfs_put_client(clp); clp = old; - atomic_inc(&clp->cl_count); } return clp; @@ -305,7 +304,7 @@ int nfs40_walk_client_list(struct nfs_client *new, .clientid = new->cl_clientid, .confirm = new->cl_confirm, }; - int status; + int status = -NFS4ERR_STALE_CLIENTID; spin_lock(&nn->nfs_client_lock); list_for_each_entry_safe(pos, n, &nn->nfs_client_list, cl_share_link) { @@ -331,28 +330,28 @@ int nfs40_walk_client_list(struct nfs_client *new, if (prev) nfs_put_client(prev); + prev = pos; status = nfs4_proc_setclientid_confirm(pos, &clid, cred); - if (status == 0) { + switch (status) { + case -NFS4ERR_STALE_CLIENTID: + break; + case 0: nfs4_swap_callback_idents(pos, new); - nfs_put_client(pos); + prev = NULL; *result = pos; dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n", __func__, pos, atomic_read(&pos->cl_count)); - return 0; - } - if (status != -NFS4ERR_STALE_CLIENTID) { - nfs_put_client(pos); - dprintk("NFS: <-- %s status = %d, no result\n", - __func__, status); - return status; + default: + goto out; } spin_lock(&nn->nfs_client_lock); - prev = pos; } + spin_unlock(&nn->nfs_client_lock); +out: /* * No matching nfs_client found. This should be impossible, * because the new nfs_client has already been added to @@ -362,9 +361,8 @@ int nfs40_walk_client_list(struct nfs_client *new, */ if (prev) nfs_put_client(prev); - spin_unlock(&nn->nfs_client_lock); - pr_err("NFS: %s Error: no matching nfs_client found\n", __func__); - return -NFS4ERR_STALE_CLIENTID; + dprintk("NFS: <-- %s status = %d\n", __func__, status); + return status; } #ifdef CONFIG_NFS_V4_1 @@ -472,6 +470,7 @@ int nfs41_walk_client_list(struct nfs_client *new, if (!nfs4_match_serverowners(pos, new)) continue; + atomic_inc(&pos->cl_count); spin_unlock(&nn->nfs_client_lock); dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n", __func__, pos, atomic_read(&pos->cl_count)); |