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| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-04-21 12:31:05 -0400 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-04-21 12:31:05 -0400 |
| commit | c77365c963cf8703ecf1004cd3b298068a3e1b76 (patch) | |
| tree | 449a02a25c425148a52c5bec073787902ad86fed /fs | |
| parent | 95b72eb0bdef6476b7e73061f0382adf46c5495a (diff) | |
| download | linux-c77365c963cf8703ecf1004cd3b298068a3e1b76.tar.gz linux-c77365c963cf8703ecf1004cd3b298068a3e1b76.tar.bz2 linux-c77365c963cf8703ecf1004cd3b298068a3e1b76.zip | |
NFSv4: Ensure that we don't drop a state owner more than once
Retest the RB_EMPTY_NODE() condition under the spin lock
to ensure that we don't call rb_erase() more than once on the
same state owner.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/nfs/nfs4state.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 3b07f094f3a9..b300fb840b21 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -435,13 +435,17 @@ nfs4_alloc_state_owner(struct nfs_server *server, static void nfs4_drop_state_owner(struct nfs4_state_owner *sp) { - if (!RB_EMPTY_NODE(&sp->so_server_node)) { + struct rb_node *rb_node = &sp->so_server_node; + + if (!RB_EMPTY_NODE(rb_node)) { struct nfs_server *server = sp->so_server; struct nfs_client *clp = server->nfs_client; spin_lock(&clp->cl_lock); - rb_erase(&sp->so_server_node, &server->state_owners); - RB_CLEAR_NODE(&sp->so_server_node); + if (!RB_EMPTY_NODE(rb_node)) { + rb_erase(rb_node, &server->state_owners); + RB_CLEAR_NODE(rb_node); + } spin_unlock(&clp->cl_lock); } } |